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Durable circulatory support with a paracorporeal device
as an option for pediatric and adult heart failure patients
Sven-Erik Bartfay, MD,
a,b
G€
oran Dellgren, MD, PhD,
b,c,d
Stefan Hallhagen, MD,
e,f
H
akan W
ahlander, MD, PhD,
e,f
Pia Dahlberg, MD,
a,b
Bengt Redfors, MD, PhD,
f,g
Jan Ekelund, MSc,
h
and
Kristjan Karason, MD, PhD
a,b,d
ABSTRACT
Objectives: Not all patients in need of durable mechanical circulatory support are
suitable for a continuous-flow left ventricular assist device. We describe patient
populations who were treated with the paracorporeal EXCOR, including children
with small body sizes, adolescents with complex congenital heart diseases, and
adults with biventricular failure.
Methods: Information on clinical data, echocardiography, invasive hemodynamic
measurements, and surgical procedures were collected retrospectively. Differences
between various groups were compared.
Results: Between 2008 and 2018, a total of 50 patients (21 children and 29 adults)
received an EXCOR as bridge to heart transplantation or myocardial recovery. The
majority of patients had heart failure compatible with Interagency Registry for
Mechanically Assisted Circulatory Support profile 1. At year 5, the overall survival
probability for children was 90%, and for adults 75%(P¼.3). After we pooled
data from children and adults, the survival probability between patients supported
by a biventricular assist device was similar to those treated with a left ventricular
assist device/ right ventricular assist device (94%vs 75%, respectively, P¼.2).
Patients with dilated cardiomyopathy had a trend toward better survival than those
with other heart failure etiologies (92%vs 70%,P¼.05) and a greater survival free
from stroke (92%vs 64%,P¼.01). Pump house exchange was performed in nine
patients due to chamber thrombosis (n ¼7) and partial membrane rupture (n ¼2).
There were 14 cases of stroke in eleven patients.
Conclusions: Despite severe illness, patient survival on EXCOR was high, and the
long-term overall survival probability following heart transplantation and recovery
was advantageous. Treatment safety was satisfactory, although still hampered by
thromboembolism, mechanical problems, and infections. (J Thorac Cardiovasc
Surg 2021;161:1453-64)
0
0
21
29
16
22
14
20
13
19
11
18
10
17
8
15
7
12
6
6
No. at risk
Children
Adults
1234
Time (years)
5678
20 P = .3
40
60
Survival probability (%)
80
100
Overall survival probability in children and adults.
CENTRAL MESSAGE
Use of the paracorporeal EXCOR
device as bridge to transplanta-
tion or recovery in children and
adults less suitable for a CF-LVAD
may offer good long-time out-
comes with satisfactory safety.
PERSPECTIVE
Not all patients in need for a long-term MCS are
suitable for a CF-LVAD, including children with
small body sizes, patients with complex congenital
heart diseases, and those with biventricular heart
failure requiring right-sided support. In such cases
treatment with the EXCOR system appears to be a
viable strategy offering good results, although still
hampered with a certain risk for complications.
See Commentaries on pages 1465, 1466, and
1467.
Today, the continuous-flow (CF) left ventricular assist
device (LVAD) is the primary durable mechanical
circulatory support (MCS) system applied for patients
with left ventricular (LV) heart failure (HF) awaiting
transplantation or recovery.
1
Still, not all patients in need
of a long-term MCS are suitable for a CF-LVAD.
2-4
Such
patients may include infants and children with small body
sizes, adolescents and adults with complex congenital
heart diseases, and patients with biventricular failure
requiring additional right-sided support. Although,
From the
a
Department of Cardiology,
c
Department of Cardiothoracic Surgery,
d
Transplant Institute,
e
Department of Pediatric Cardiology, Queen Silvia
Children’s Hospital,
g
Department of Cardiothoracic Anesthesia and Intensive
Care, and
h
Centre of Registers V€
astra G€
otaland, Sahlgrenska University Hospital,
Gothenburg; and Institutes of
b
Medicine and
f
Clinical Sciences, Sahlgrenska
Academy, University of Gothenburg, Sweden.
Grants-in-aid have been received from the Swedish federal government under the
ALF agreement (ALFGBG-775351 and 725971) and from the Swedish
Heart-Lung Foundation (project number 20160671).
Received for publication Nov 13, 2019; revisions received April 9, 2020; accepted for
publication April 13, 2020; available ahead of print May 15, 2020.
Address for reprints: Sven-Erik Bartfay, MD, Department of Cardiology, Sahlgrenska
University Hospital, University of Gothenburg, SE- 413 45, G€
oteborg, Sweden
(E-mail: sven-erik.bartfay@vgregion.se).
0022-5223/$36.00
Copyright Ó2020 by The American Association for Thoracic Surgery
https://doi.org/10.1016/j.jtcvs.2020.04.163
The Journal of Thoracic and Cardiovascular Surgery cVolume 161, Number 4 1453
Bartfay et al Congenital: Mechanical Circulatory Support
CONG
short-term extracorporeal life support can be life-saving in
these situations, the prolonged use of such systems is
associated with significant morbidity and mortality
5,6
and
has a negative effect on posttransplant outcomes.
7-10
The Berlin Heart EXCOR system (Berlin Heart, GmbH,
Berlin Germany) is a paracorporeal, pneumatically driven
blood pump that delivers a pulsatile flow and can provide
durable support of the LV, the RV, or both ventricles.
11
The device is available in a wide range of sizes that are
developed to support both children and adults and is
applicable for patient populations who are not suitable for
CF-LVADs.
6,12
In Europe, the system is approved for both
children and adults, but in the United States, its use is
only granted for children.
13
As compared with CF-LVAD,
the extracorporeal EXCOR device inflicts a greater
intrusion on quality of life and results in greater complica-
tion rates. This influences its application as a bridge to
transplantation and precludes its use as destination therapy.
At our institution, the EXCOR system has been used in
children as a bridge to transplant (BTT) or recovery since
2008 and in adults as a BTT since 2010. The aim of this
study was to describe patients receiving EXCOR pumps,
their preimplantation profiles, outcomes, and pump-
related complications. Apart from comparing the outcomes
of children versus adults, we also studied the results for
various subgroups to explore the effect of EXCOR
treatment in different patient populations.
PATIENTS AND METHODS
Patient Demographics
Between April 2008 and December 2018, a total of 50 patients (21 chil-
dren and 29 adults) received an EXCOR device (Berlin Heart GmbH) at
Sahlgrenska University Hospital. All patients were included in the present
analysis. In children, the strategy with long-term MCS could be either BTT
or myocardial recovery, whereas all adults received the device as BTT.
At our pediatric department, the EXCOR device has been used as the
primary system for long-term MCS in infants and children, mainly due
to the scarcity of other durable alternatives. Thus, for children with small
body sizes, the EXCOR was considered the only option for bridge to heart
transplantation (HTx) or recovery. Notably, 3 older children with larger
body sizes received an HVAD, but they are not included in the present
analysis.
In adolescents and adults, we have used the system in selected patients
considered ineligible for CF-LVAD, including those with complex
congenital heart disease in whom intracorporeal device placement can be
challenging and in patients in need for biventricular support.
After experiencing inferior results following LVAD implantation in
critically ill adults with poor RV function, we adapted a more liberal use
of planned in advance biventricular assist device (BiVAD). The decision
to apply a BiVAD as treatment strategy was based on the estimated risk
for postimplant RV failure after a multidisciplinary evaluation of clinical,
echocardiographic, and hemodynamic status.
Blood samples were analyzed at the Central Laboratory of Sahlgrenska
University Hospital (accredited according to European norm 45001). The
study protocol was approved by the central ethical review board at the
University of Gothenburg (Registration number 728-12).
Echocardiography
All patients were examined preoperatively according to standard trans-
thoracic echocardiography protocols for children and adults, respectively.
RV dysfunction and tricuspid valve regurgitation were graded as none
(0), mild (1), moderate (2), or severe (3). Tricuspid annular plane systolic
excursion and tissue Doppler velocity imaging of the RV free wall were
measured in adults only due to differences in the examination protocols.
Invasive Hemodynamic Measurements
Invasive hemodynamic data from right heart catheterizations were ob-
tained in all adults and in the majority of children. These measurements
were performed as part of heart failure workup before decision-making
on EXCOR treatment. In patients compatible with Interagency Registry
for Mechanically Assisted Circulatory Support (INTERMACS) profile 1,
who were admitted acutely and required extracorporeal membrane
oxygenation (ECMO) support, the hemodynamic profile was acquired in
the intensive care unit. Central venous pressure, right atrial pressure,
mean pulmonary artery pressure, and pulmonary capillary wedge pressure
were measured with a Swan–Ganz catheter, and cardiac output was
determined by the Fick method in children and the thermodilution
technique in adults. Pulmonary vascular resistance was calculated as the
pressure difference between mean pulmonary artery pressure and
pulmonary capillary wedge pressure divided by cardiac output and ex-
pressed as Wood units.
Surgical Procedure
The surgical introduction of the EXCOR pump was performed in a stan-
dard fashion using sternotomy and extracorporeal circulation in both chil-
dren and adults. In most of the children, cannulas were implanted after
induction of ventricular fibrillation. This was found to be practical by the
pediatric surgeons, who have gained significant experience performing
short procedures during ventricular fibrillation. This method facilitated
emptying air from the ventricle and did not in any way affect RV function.
Cardioplegia was used in 4 children and in 1 child the cannula was inserted
Abbreviations and Acronyms
BiVAD ¼biventricular assist device
BTT ¼bridge to transplantation
CF ¼continuous flow
DCM ¼dilated cardiomyopathy
ECMO ¼extracorporeal membrane
oxygenation
HF ¼heart failure
HTx ¼heart transplantation
INTERMACS ¼Interagency Registry for
Mechanically Assisted Circulatory
Support
LV ¼left ventricular
LVAD ¼left ventricular assist device
MCS ¼mechanical circulatory support
RV ¼right ventricular/ventricle
RVAD ¼right ventricular assist device
Scanning this QR code will
take you to the table of con-
tents to access supplementary
information.
1454 The Journal of Thoracic and Cardiovascular Surgery cApril 2021
Congenital: Mechanical Circulatory Support Bartfay et al
CONG
on a beating heart. For systemic ventricle support, the LV apex was cannu-
lated in 15 patients, the RVin one, and both ventricles were supported in 5.
In 4 children the left atrium was cannulated due to restrictive LV
physiology, in 2 for anatomical considerations (1 child with congenitally
corrected transposition of the great arteries and 1 child with myocarditis
to facilitate device explantation). Seven of the children were supported
with ECMO before durable EXCOR therapy was applied, and 2 had
received cardiopulmonary resuscitation before implantation of the
short-term MCS.
In adults receiving EXCOR as a BiVAD, implantation of cannulas was
performed on a beating heart. Cannulas according to size of patients were
inserted in the following sequence of order: left ventricular apex; right
atrium; pulmonary artery; and aorta. Each cannula was carried through
the skin in a similar fashion, ensuring appropriate distance between exit
sites.
Both children and adults were weaned from extracorporeal circulation
without inotropic support by connecting the EXCOR cannulas to short-
term MCS devices (CentriMag [Abbott, Pleasanton, Calif] for children
and Rotaflow PLS system [Maquet, Rastatt, Germany] for adults). After
initial recovery, when patients were extubated and found to be neurologi-
cally intact, an exchange from the short-term MCS devices to the EXCOR
pump houses was performed in a separate short procedure before leaving
the intensive care unit.
Postoperative Management and Follow-up
Heparin infusion was initiated when bleeding had ceased postopera-
tively (24-48 hours) and activated partial thromboplastin time was targeted
at 40 to 50 seconds. Warfarin treatment was started after the removal of
chest tubes with international normalized ratio (INR) targeted at 2.5 to
3.5. Patients also received aspirin at a dose of 75 mg daily. In a few cases,
where frequent thrombus formation in the pump houses had occurred, clo-
pidogrel 75 mg was added after consulting a coagulation specialist. With
respect to blood pressure control we aimed at levels 130/80 mm Hg. After
stabilization, the patients were transferred to the cardiology ward, where
they received physiotherapy and self-care training. Patients who remained
clinically stable and had adequate social support were discharged to home
with the “Excor mobile driving unit.”
After HTx or weaning involving explantation of the EXCOR device, all
patients were followed up at an outpatient clinic dedicated for HTx or HF,
respectively. Within the frame of the study, we registered the occurrence of
death and stroke (major and minor) during a maximum period of 8 years
following EXCOR treatment.
Statistics
Statistical analyses were performed with JMP 10 and SAS 9.4 statistical
software (SAS Institute, Cary, NC). Data are presented as means and
standard deviations, medians and interquartile ranges, or numbers and
percentages. Comparisons between children and adults were performed
for all variables, despite self-evident disparities, to underline the
differences between these 2 groups. Still, since many variables were similar
between children and adults, we allowed us to pool data from the 2 groups
to increase the power for other statistical analyses. Statistical comparisons
between children and adults both at baseline and during follow-up were
performed with an unpaired ttest for normally distributed data,
Mann–Whitney Utest for nonparametric data and Fisher exact test for
categorical data.
Cumulative incidence of HTx or weaning during the first year was
estimated with competing risks regression models according to the model
by Fine–Gray.
14
In these analyses, deaths were treated as competing events.
Comparison of the following subgroups were performed: children versus
adults; male versus female; LVAD/right ventricular assist device (RVAD)
treatment versus BiVAD treatment; dilated cardiomyopathy (DCM) HF
etiology versus other HF etiologies; and INTERMACS ¼1 versus
INTERMACS>1.
Curves for overall survival and for survival free from major stroke were
completed. In the latter analysis, we comprised a combined end point,
including time to stroke or time to death, whichever came first, and
censored alive patients without stroke with a cut off after a maximum of
8 years. Kaplan–Meier curves were generated for children versus adults;
male versus female; LVAD/RVAD treatment versus BiVAD treatment;
DCM HF etiology versus other HF etiologies; and INTERMACS ¼1
versus INTERMACS>1. Since time to death was applied as an end point
and not as a competing event, the use of the competing risk in these ana-
lyses is inadequate and comparison between the groups was achieved
with the Wilcoxon test.
RESULTS
Patient Characteristics
During the study period, participants were treated with
the EXCOR system for a total of 5990 days. Among
children for 2062 days and among adults for 3928 days. De-
mographics, medical history, and preoperative laboratory
values are shown in Table 1. The distribution of sex was
similar for both pediatric and adult study groups. More chil-
dren had undergone previous cardiac surgery as compared
with adults, but heart failure duration was shorter for chil-
dren than for adults. In all of the children and in 97%of
the adults the heart failure etiology was nonischemic.
Table 2 displays preoperative echocardiography data; he-
modynamic status; need for circulatory, ventilatory or renal
support; and clinical heart failure severity (INTERMACS
profiles). Echocardiography showed similar LV ejection
fraction in both children and adults. Severe impairment of
RV function was more common in adults, reflecting the se-
lection of the EXCOR system as a BiVAD treatment. The
presence of 2 or more of the risk factors for postoperative
RV failure listed in Table E1 favored BiVAD implantation.
Invasive hemodynamic measurements displayed high
filling pressures and low flow with severely reduced mixed
venous saturation in both groups. The use of intravenous
inotropic support was high in both children and adults.
Treatment with various types of short-term MCS devices
was common in both study groups, and ECMO was used
in 7 children (47%) and in 9 adults (34%). The majority
of patients were compatible with INTERMACS profile 1,
with no differences between children and adults. The
different types of congenital heart disease in patients treated
with EXCOR are displayed in Table E2. Separate consort
diagrams for children and adults showing the use of all
types of long-term MCS support at our center during the
study period are provided in Figures E1 and E2.
Treatment Strategy, Hospital Stay, and Time on
Assist
Table 3 presents treatment strategy, hospital stay, and
time on assist in children and adults, respectively. The de-
vice was used as an LVAD in 15 children, as an RVAD in
one child, and as a BiVAD in 5 children. The child, who
received the device as an RVAD, had a univentricular heart
The Journal of Thoracic and Cardiovascular Surgery cVolume 161, Number 4 1455
Bartfay et al Congenital: Mechanical Circulatory Support
CONG
defect consisting of hypoplastic left heart syndrome and had
undergone Norwood and a subsequent bidirectional Glenn
procedure. The child had the device implanted in the
morphological RV, which supported the systemic
circulation.
One child with congenitally corrected transposition had
the morphologic RV as the systemic ventricle and had the
device for support of the systemic circulation with cannulas
implanted in the left atrium and aorta. In the adult
population, the system was used as an LVAD in 1 patient,
and as a BiVAD in 25 subjects. The adult patient, who
received the device as an LVAD had a history of
transposition of the great arteries, Senning correction,
Rashkind septostomy, and recent ICD-lead endocarditis.
The patient was converted from ECMO to short-term
LVAD connected through the Excor cannulas, and later on
equipped with an EXCOR pump house.
At the beginning of our program, we had a restrictive
attitude toward discharging patients with paracorporeal
devices. After our experience with the system increased,
we became aware that it was feasible to discharge patients
to their home. One child aged 10 years of age and 13 adults
were discharged to home on device during the wait time
(P¼.002). These patients were followed closely at a
cardiac daycare facility with trained staff. Family members
and home nurses were also trained to perform daily inspec-
tions of the pump houses and regular check-up of the sys-
tem. In cases where the patients lived in another region of
the country, members of our team trained the staff at the
local hospital. The longest treatment on pump was
344 days, of which the patient spent 30 days at home.
The patient with the longest time of home support had a to-
tal time on device of 327 days, of which he spent 255 days at
home. The most common out of hospital complication
included wound infections around the cannulas, which in
some cases required hospitalization and treatment with
intravenous antibiotics. In general, patients discharged to
home tended to do better than those who remained
hospitalized (data not shown).
HTx and Weaning
HTx was performed in 12 children (57%) and 24 adults
(83%)(P¼.05). Myocardial recovery allowing for
explantation occurred in 8 children (38%) and 1 adult
(3%)(P<.001). The heart failure etiologies associated
with myocardial recovery in children included
tachycardia-induced cardiomyopathy (n ¼2), DCM
(n ¼1), myocarditis (n ¼2), congenital aortic stenosis
TABLE 1. Demographics, medical history, and preoperative laboratory values in pediatric and adult patients
Pediatric patients (n ¼21) Adult patients (n ¼29) Pvalue
Demographics
Age, y 5 (1-11) 35 (23-48) <.001
Female sex 10 (48) 12 (41) .7
Body mass index, kg/m
2
16 2254<.001
Body surface area, m
2
0.79 0.48 1.96 0.27 <.001
Medical history
Hypertension 1 (5) 0 (0) .2
Diabetes 0 (0) 1 (3) .4
Atrial fibrillation/flutter 2 (10) 6 (21) .3
Myocardial infarction 0 (0) 2 (7) .2
Previous cardiac surgery 14 (67) 7 (24) .003
Duration of heart failure, mo 0.5 (0.1-1) 6 (1-66) .006
Etiology of heart failure
Dilated cardiomyopathy 9 (43) 17 (59) .3
Congenital heart disease 6 (29) 2 (7) .04
Myocarditis/inflammatory heart disease 2 (10) 4 (14) .6
Postoperative/procedural complications 0 (0) 3 (10) .1
Ischemic heart disease 0 (0) 1 (3) .4
Graft failure post–heart transplantation 1 (5) 0 (0) .2
Other 3 (14) 2 (7) .4
Laboratory values
Hemoglobin, g/L 112 25 120 19 .2
Creatinine, mmol/L 43 28 120 50 <.001
Aspartate aminotransferase, mkat/L 1.3 (0.9-2.7) 0.7 (0.5-3.4) .08
Alanine aminotransferase, mkat/L 1.3 (0.4-1.7) 0.8 (0.4-1.7) .6
Bilirubin, mmol/L 12 (6-15) 20 (14-33) <.001
Values are presented as means standard deviation, numbers (%), or medians (interquartile range).
1456 The Journal of Thoracic and Cardiovascular Surgery cApril 2021
Congenital: Mechanical Circulatory Support Bartfay et al
CONG
(n ¼1), and anomalous left coronary artery from the
pulmonary artery (n ¼2). The adult patient that was weaned
from the EXCOR system had suffered from a perioperative
myocardial infarction. Seven children who underwent
explantation after 31, 46, 73, 77, 79, 84, and 110 days
(6 LVADs and 1 BiVAD) survived without recurrent heart
failure or need for heart transplantation. However, one
child, who underwent LVAD explantation after 59 days,
developed restrictive myocardial physiology and died of
cardiogenic shock three months later. The adult
patient, who underwent BiVAD explantation after
79 days, had developed a stroke and was not any longer
considered a transplant candidate despite compromised
cardiac function, and died of neurologic sequalae 5 months
later.
One child (5%) died on pump due to severe
gastrointestinal bleedings and multiple organ failure at
day 180. In the adult group, 4 patients died on pump
(14%): 1 of multiple organ failure at day 17, 1 due to a
stroke at day 32, 1 due to stroke at day 97 (following
multiple infectious complications), and 1 following a major
cerebral bleed at day 245.
TABLE 2. Preoperative clinical heart failure severity and hemodynamic status and circulatory, ventilatory, and renal support
Children (n ¼21) Adults (n ¼29) Pvalue
Echocardiographic measurements
Left ventricular ejection fraction, %23 8198.2
Severe RV failure 3 (15) 24 (83) <.001
TVR grade, 0-3 1.7 1.0 1.9 0.8 .6
TAPSE, cm ND 1.3 0.3 ND
RV free wall peak tissue velocity, cm/s ND 7.0 2.1 ND
Invasive hemodynamic measurements
Heart rate, beats/min 129 18 104 27 .06
Right atrial pressure, mm Hg 12 4145.4
Mean pulmonary artery pressure, mm Hg 37 14 31 15 .4
Pulmonary capillary wedge pressure, mm Hg 23 8205.3
Systolic blood pressure, mm Hg 83 15 92 10 .03
Cardiac index, L/min/m
2
2.7 0.5 1.5 0.5 .001
SvO
2
,%56 55211 .5
Circulatory, ventilatory and renal support
Intravenous inotropic therapy 18 (86) 25 (86) .9
Short-term mechanical circulatory support*11 (73) 19 (73) .9
Mechanical ventilation 13 (62) 13 (45) .2
Continuous renal-replacement therapy 2 (10) 7 (26) .2
Clinical heart failure severity
INTERMACS profile 1 (vs 2-5) 9 (60) 16 (62) .9
Valuesare presented as means standard deviation or n (%). RV, Right ventricular; TVR, tricuspid valve regurgitation; TAPSE,tricusp id annular plane systolic excursion; ND, not
done; SvO
2
, mixed venous saturation; INTERMACS, Interagency Registry for Mechanically Assisted Circulatory Support. *Short-term (ST) mechanical circulatory support
involved different combinations of intra-aortic balloon pump, extracorporeal membrane oxygenation; ST-left ventricular assist device, or ST-biventricular assist device
TABLE 3. Treatment strategy, hospital stay, time on assist, and outcome
Children (n ¼21) Adults (n ¼29) Pvalue
Type of assist
LVAD 15 (71) 1 (3) <.001
RVAD (supporting the systemic circulation) 1 (5) 0 (0) .4
BiVAD 5 (24) 28 (97) <.001
Hospital stay, time on assist, discharge
Length of stay in ICU, d 15 (11-29) 18 (7-30) .9
Length of stay in hospital, d 79 (39-111) 66 (43-100) .6
Time on assist, d 79 (39-239) 136 (81-185) .08
Discharge to home on device 1 (5) 13 (45) .002
HTx and recovery
Heart transplantation 12 (57) 24 (83) .05
Recovery 8 (38) 1 (3) .002
Death on device 1 (5) 4 (14) .3
Values are presented as numbers (%) or median (interquartile range). LVAD, Left ventricular assist device; RVAD, right ventricular assist device; BiVAD, biventricular assist
device; ICU, intensive care unit; HTX, heart transplantation.
The Journal of Thoracic and Cardiovascular Surgery cVolume 161, Number 4 1457
Bartfay et al Congenital: Mechanical Circulatory Support
CONG
Short-Term Survival and Wait Times on Device
The proportion of the total study population surviving on
device until heart transplantation or weaning was 90%. All
survivors were transplanted or weaned from the pump
within 1 year of follow-up (Figure 1). No patient was
considered for destination therapy. Children were listed
for HTx directly after pump-implantation. Time to
transplantation or weaning was shorter for children
(85 days; interquartile range 46-165 days), than for adults
(125 days; interquartile range 76-186 days) (P¼.03),
who were listed first after a 3-month rehabilitation period
(Figure 1,A). When data from children and adults were
pooled, there was no significant difference between females
and males with respect to time to HTx/weaning
(Figure 1,B). The patients who received an LVAD or
RVAD, were mainly children and had a shorter wait time
to HTx/weaning than those who were treated with a BiVAD,
largely adults (P¼.007) (Figure 1,C). There was no
difference in wait time between those who had DCM
compared with those that with other HF etiologies
0
20
40
60
80
Probability for HTx/weaning (%)
100
0
A
100
Adults Children Males Females
BiVAD LVAD/RVAD Dilated cardiomyopathy Other HF etiolog
y
200
P = .03
Time (days)
300
0
20
40
60
80
Probability for HTx/weaning (%)
100
0
B
100 200
P = .8
Time (days)
300
0
20
40
60
80
Probability for HTx/weaning (%)
100
0
C
100 200
P = .007
Time (days)
300
0
20
40
60
80
Probability for HTx/weaning (%)
100
0
D
100 200
P = .8
Time (days)
300
FIGURE 1. Time on EXCOR device to HTx (n ¼36) or weaning (n ¼9) during the first year of follow-up in different subgroups. A, Children versus adults;
B, males versus females; C, treatment with BiVAD versus LVAD/RVAD; and D, DCM versus other heart failure etiology. Cumulative incidence of HTx or
weaning during the first year was estimated with competing risks regression models, in which deaths were treated as competing events. HTx, Heart trans-
plantation; BiVAD, biventricular assist device; LVAD, left ventricular assist device; RVAD, right ventricular assist device; HF, heart failure.
1458 The Journal of Thoracic and Cardiovascular Surgery cApril 2021
Congenital: Mechanical Circulatory Support Bartfay et al
CONG
(Figure 1,D). Patients compatible with INTERMACS
profile 1 had similar wait times to HTx and recovery
as those with INTERMACS levels 2 or greater
(Figure E3,A). Figure 2 depicts competing outcomes with
respect to survival, cumulative HTx, recovery, and mortality
in children (Figure 2,A) and in adults (Figure 2,B),
respectively.
Adverse Events Related to EXCOR Treatment
Thirty-day postoperative complications and pump-related
complications are shown in Table 4. Complications within
1 month after device introduction included reoperations
due to bleeding, need for continuous renal-replacement
therapy, mediastinitis, pneumonia, and different types of
hospital-acquired bacteremia. These complications did not
differ between children and adults. Among pump-related
complications, during the entire time of support, there were
14 cases of stroke in 11 patients. In 6 patients (5 adults and
1 child) the strokes were major (defined as considerable re-
sidual neurologic symptoms). Five of six major strokes
were primarily ischemic and one was hemorrhagic. In 3 of
these cases, the strokes were directly linked to the patients’
death. The 6 patients with minor strokes had no or very
discrete residual neurologic symptoms. One child had a sub-
arachnoid hemorrhage but showed no residual symptoms at
the time of discharge.
The potential development of fibrin depositions, red
clots, or white thrombus on the inflow or outflow valves
was followed with close surveillance. If this occurred, our
first response was to optimize the anticoagulation. If inter-
national normalized ratio was below 2.5 we added low mo-
lecular heparin subcutaneously and adjusted the warfarin
dose. If antithrombin III was low (<0.8 KIE/L) this was
given intravenously in an adequate dose. In some cases,
we added clopidogrel 75 mg after consulting a coagulation
specialist. Pump chamber thrombosis requiring intervention
occurred in 5 children and four adults, and in most cases
pump chamber exchange was performed in the operation
theater. In selected cases, the pediatric thoracic surgeons
dismantled the pump house and if easily accessible
removed red clots and thrombi after which they rinsed the
pump house with saline. Subsequently, the pump house
was reattached to the cannulas. In adults we attempted to
optimize the anticoagulation regime for a longer period of
time before performing any interventions.
Two cases of membrane rupture among adults were
solved by urgent pump chamber exchange. Cannula infec-
tion requiring antibiotics occurred in 5 children and 7
adults. Bleeding complications were uncommon. One child
suffered from a major gastrointestinal bleeding that was
eventually fatal. After HTx or weaning, we only registered
death and stroke as adverse events.
Long-Term Survival During and After EXCOR
Treatment
Overall survival probability and survival free from major
stroke through a maximal follow-up of 8 years during and
after EXCOR treatment is depicted in Figure 3,
Figure E3,Band C, and Figure E4. Note that “survival
free from major stroke”is a combined end point, including
time to stroke or time to death, whichever came first. During
a median follow-up of 5.4 years (interquartile range
2.6-7.7 years) the survival probability for children at 1
and 5 years was 90%and 90%, respectively. The
corresponding survival probability for adults was 82%
and 75%, respectively (Figure 3,A). When data from
A
0
0 50 100 150 200
Time (Days)
250 300 350
20
40
Percent of patients
80
60
100
Children
Heart transplantation
Recovery
Overall survival
Death
B
0
050
Adults
100 150 200
Time (Days)
250 300 350
20
40
Percent of patients
80
60
100
Heart transplantation
Recovery
Overall survival
Death
FIGURE 2. Outcomes for children and adults after implantation of the
EXCOR device. A, All outcomes over time for children during 12 months
of follow-up after EXCOR implantation. B, All outcomes over time for
adults during 12 months of follow-up after EXCOR implantation.
The Journal of Thoracic and Cardiovascular Surgery cVolume 161, Number 4 1459
Bartfay et al Congenital: Mechanical Circulatory Support
CONG
children and adults were pooled, there was no difference
in survival probability between those treated with a
BiVAD and those in whom one ventricle was supported
(LVAD/RVAD) (Figure 3,C). With respect to survival
free from stroke the time to event appeared earlier, but since
cerebral strokes were the main cause of death in children vs
adults, and in those with BiVAD vs LVAD/RVAD, long-
term survival was largely unchanged (Figure 3,Band D).
In a similar manner, there were no differences between fe-
male and male patients (Figure E4,Aand B). Patients
who had DCM as heart failure etiology had a strong trend
toward better overall survival (96%at year 1 and 92%at
year 5) compared with those with other HF etiologies
(75%at year 1 and 70%at year 5) (P¼.05). Survival
free from major stroke was significantly greater in patients
with DCM compared with those with other HF etiologies
(92%vs 64%after 5 years, P¼.01) (Figure E4,Cand
D). Patients compatible with INTERMACS profile 1 had
a similar long-term outcome as those with INTERMACS
levels 2 or higher (Figure E3,Band C).
DISCUSSION
The present study supports the usefulness of the
paracorporeal EXCOR-system as BTT or recovery in both
children and adults with advanced heart failure who are
less suitable for CF-LVADs. Considering the severity of
their illness, survival on device and long-term survival
probability following HTx or recovery was high and better
than previously reported.
6,15-18
The safety of the system was
acceptable, although the treatment is still hampered by
complications including thromboembolism, mechanical
problems, and infections.
Most implantable MCS are developed to support a failing
LV causing inadequate circulation in adult patients.
Although there has occurred a certain miniaturization along
with the transition from pulsatory to continuous flow
techniques, there is still the issue of a device–body size
mismatch in children. The remaining alternatives for these
patients have been nonpulsatile ECMO and centrifugal
pumps, which demand continuous care in the intensive
care unit, resulting in immobilization, increased risk for in-
fections, thromboembolic events, and poor outcome.
6,8-10
For longer-term support, the only realistic option for infants
and small children has been the paracorporeal EXCOR
pump.
6,15
The 21 children treated with the EXCOR system
in our study could be transferred to the general ward and one
child was discharged to home during the wait time for HTx.
The children displayed an excellent survival on the EXCOR
pump to HTx or recovery, followed by a high long-term
survival probability.
Advances in neonatal care consisting of improved
detection and repair of complex cardiac lesions has led to
a growing population of adolescents and adults with
complex congenital heart disease. These patients have an
increased risk for heart failure and have a high mortality
risk.
19
Therefore, this patient population constitutes an
increasing need for a durable MCS as bridge to heart
transplantation. However, the implantation of a CF-LVAD
in these cases can be problematic due to anatomic variations
that may render device placement difficult. Further, data on
the treatment of patients suffering from congenital heart
disease with durable MCS are scarce. In the present study
a total of 6 patients (4 children and 2 adults) with complex
congenital heart disease received an EXCOR system as
bridge to HTx or recovery. Four patients (3 children and 1
adult) underwent HTx; in 1 child myocardial function
recovered permitting explantation of the device; and 1 adult
died on device. The 1- and 5-year survival probability for
TABLE 4. Summary of adverse events: postoperative complications up to 30 days after pump implantation and all pump-related complications
during EXCOR treatment
Children (n ¼21) Adults (n ¼29) Pvalue
Postoperative complications
Reoperation due to bleeding 7 (33) 10 (34) .9
Continuous renal-replacement therapy 2 (10) 3 (10) .8
Mediastinitis (ABX-treated) 0 (0) 3 (10) .1
Pneumonia (ABX-treated) 1 (5) 5 (17) .2
Hospital-acquired bacteremia (ABX-treated) 2 (10) 6 (21) .3
n(%) Events/pat yr. n (%) Events/pat yr.
Pump-related complications
Major stroke 1 (5) 0.18 5 (17) 0.46 .2
Minor stroke 4 (19) 0.71 5 (17) 0.46 .9
Pump thrombosis requiring intervention 5 (24) 0.88 4 (14) 0.37 .4
Mechanical pump failure 0 (0) 0.00 2 (7) 0.19 .2
Cannula infection treated with ABX 5 (24) 0.88 7 (27) 0.65 .9
Values are presented as numbers (%) and events per patient years. ABX, Antibiotics.
1460 The Journal of Thoracic and Cardiovascular Surgery cApril 2021
Congenital: Mechanical Circulatory Support Bartfay et al
CONG
these patients were 83%at both time points, which is high,
considering the anatomical complexity of their cardiac mal-
formations and the severity of their illness.
The treatment of severe biventricular HF with MCS is
controversial. Early right HF develops in approximately
20%to 30%of all LVAD recipients and is
associated with a substantial increase in mortality.
20-22
The management of this problem with a subsequent
short-term right-sided assist or durable CF-RVAD during
the wait for HTx or recovery is associated with a
less-favorable outcome, often with 1-year survival in the
range of 50%to 70%or less.
23,24
In previous systematic
evaluations using older paracorporeal systems, treatment
has also consistently shown worse outcomes.
25-27
In
contrast, there are data suggesting that preplanned BiVAD
implantation in patients with a high risk of RV failure is
better than subsequent conversion from LVAD to
BiVAD.
28
In a previous study, we observed that patients
with high risk of postimplant RV failure experienced
excellent survival rates when subjected to a planned in
advance BiVAD strategy using the paracorporeal EXCOR
system.
29
The outcomes for these patients were similar to
that observed for contemporary LVAD recipients. These
findings are confirmed in the present study in which patients
with biventricular failure displayed a high survival on
device to HTx and a good long-term survival probability.
During the recent years, we have observed that patients
are referred for HTx workup earlier in their disease course,
and prior to the development of severe right ventricular
failure. This, along with the development of miniature,
but powerful intracorporal CF LVADs, may diminish the
need for BiVAD implantation in the future.
Due to its versatility as a circulatory support system, our
findings suggest that the EXCOR pump is a valuable option
0
0
A
21
29
16
22
14
20
13
19
11
18
10
17
8
15
7
12
6
6
No. at risk
Children
Adults
1234
Time (years)
5678
20
P = .3
40
60
Survival probability (%)
80
100
0
0
B
21
29
16
22
14
20
13
19
11
18
10
17
8
15
7
12
6
6
No. at risk
Children
Adults
1234
Time (years)
5678
20
P = .2
40
60
Survival probability
free from major stroke (%)
80
100
0
0
C
17
33
16
27
15
23
12
20
10
19
10
17
8
15
7
12
5
7
No. at risk
LVAD/RVAD
BiVAD
1234
Time (years)
5678
20
P = .2
40
60
Survival probability (%)
80
100
0
0
D
17
33
13
25
13
21
12
20
10
19
10
17
8
15
7
12
5
7
No. at risk
LVAD/RVAD
BiVAD
1234
Time (years)
5678
20
P = .2
40
60
Survival probability
free from major stroke (%)
80
100
FIGURE 3. Overall survival probability and survival free from stroke for patients throughout and after EXCOR treatment during 8 years of follow-up.
Overall survival in: A, children versus adults; B, survival free from disabling stroke in children versus adults; C, overall survival in patients receiving
BiVAD versus LVAD/RVAD; and D, overall survival in patients with DCM vs other heart failure etiology. LVAD, Left ventricular assist device;
RVAD, right ventricular assist device; BiVAD, biventricular assist device.
The Journal of Thoracic and Cardiovascular Surgery cVolume 161, Number 4 1461
Bartfay et al Congenital: Mechanical Circulatory Support
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in patients ineligible for CF-LVAD.
30
The EXCOR device
offers a longer circulatory support, allowing for improved
nutrition status, mobilization with optimization of fitness,
and recovery of organ dysfunction and a better outcome
than bridging with short-term MCS. Children were listed
for HTx directly after EXCOR implantation, whereas adults
were admitted to a 3-month rehabilitation program before
HTx listing for optimization in order to minimize operative
risks. This approach may result in loss of adult patients on
pump, but outweighs, in our opinion, the risk of organ
waste associated with death following a high-risk
transplantation. Thus, we believe that the strategy of
optimizing adults for three months before HTx listing is
adequate and can improve long-term survival in this
severely ill population.
In the present study, a total of 42%of patients were
discharged to home during wait time for HTx, which is
likely to reduce operative risks. At our center, average
wait times are short, which probably, in part, limits the
risk for development of long-term complications and
contributes to a good long-term outcome. The longest
time on pump was 344 days and the longest time on
pump at home was 255 days. Due to patient discomfort
and an increased risk for complications, a pulsatile BiVAD
is not suitable for an extended period of treatment.
Therefore, if EXCOR became available for adults in the
United States, we would propose that patients on this device
should receive a higher priority than those treated with a
CF-LVAD.
As expected, there were several differences between
children and adults with respect to EXCOR treatment.
More children had congenital heart disease, and they had
lower creatinine due to lower muscle mass. Cardiac index
was greater in children, which is a known phenomenon.
31
A majority of children received the EXCOR as an LVAD,
whereas in adults the pump-system was almost exclusively
implanted as a BiVAD, which illustrates the versatility of
the device. A significantly greater proportion of adults
were discharged with the device. Further, the rate of
myocardial recovery was much higher in children. Our
findings suggest that the likelihood of myocardial recovery
is related to age, disease duration and heart failure etiology.
Patients of younger age with short disease duration and
reversible causes of heart failure, such as myocardial
inflammation or tachyarrhythmia, are more likely to
embrace a potential for reverse remodeling. Among the
eight children who experienced recovery of myocardial
function allowing for pump explantation, 7 had either
tachycardia-induced-cardiomyopathy, myocarditis or
persistent severe heart failure after a surgical procedure.
These diagnoses were less common among children who
did not recover, although no statistical differences between
groups could be shown due to small numbers. The 2
children with myocarditis were first treated with
short-term MCS, but did not recover within a reasonable
time period. Therefore, the treatment was converted to
EXCOR-LVAD, which could be successfully explanted
later on. In contrast, adults with long-term disease duration
who do not respond to conventional pharmaceutical or
resynchronization therapy are unlikely to show myocardial
recovery allowing for explantation. Long-term survival was
slightly greater in children than in adults, but this was not
statistically significant. The wait time for HTx was
significantly shorter for children, which can be explained
by the practice to accept children for the wait list directly
after pump-implantation, where adults are normally not
admitted to the waitlist until they have performed our
3-month rehabilitation program.
In line with previous reports,
6,32
a significant number of
patients were affected by procedure or device related
adverse events during the present study. Early
complications included bleeding, need for continuous
renal-replacement therapy, mediastinitis and pneumonia,
with similar frequencies in children and adults.
Pump-thrombosis requiring intervention occurred in 24%
of children and 14%of adults. This was managed mostly
with pump change, but in some children the thrombus
was removed following dismantling of the pump, which
after rinsing was re-attached again. Although the relatively
high frequency of stroke is a clear drawback related to
EXCOR treatment, only a small proportion of this adverse
event led to permanent sequelae (1 child and 5 adults). In
contrast, a major stroke frequently led to death later on. In
the present study patients with DCM had a significantly
greater survival free from major stroke compared with those
with other heart failure diagnoses. This probably reflects a
more complicated course in those with congenital heart dis-
ease or other more complex cardiac disorders. Although the
occurrence of cannula infection was significant, this prob-
lem could be solved with oral or intravenous antibiotics.
Limitations
The observational, retrospective nature of the study is an
important limitation with respect to the type of evidence we
can provide. Also, the moderate sample size and differences
between adults and children constrain our conclusions.
Patients with more complex congenital heart disease
(n ¼6) were too few to able us to draw strong conclusions
about this group. We did not use uniform criteria to select
the treatment strategy of LVAD or BIVAD; instead the
decision was made on a multidisciplinary conference based
on the estimated risk for postimplant RV failure. Although
there were evident differences between children and adults,
there were also several similarities, which allowed us to
pool the 2 groups for certain statistical analyses. We
acknowledge that EXCOR use has been previously
described in pediatric populations. However, much less
information about the use of the system in adults is available
1462 The Journal of Thoracic and Cardiovascular Surgery cApril 2021
Congenital: Mechanical Circulatory Support Bartfay et al
CONG
and the novelty of our study lies mainly in the application of
the system in adults.
CONCLUSIONS
Not all patients in need for a long-term MCS are suitable
for a CF-LVAD, including infants and children with small
body sizes, adolescents and adults with complex congenital
heart diseases, and patients with biventricular failure
requiring additional right-sided support. Considering the
severity of patient illness and disease complexity in many
of our cases, the use of the paracorporal EXCOR as a bridge
to transplantation or recovery resulted in a high survival. In
addition, the overall long-term survival after HTx or recov-
ery was remarkably good. Still, EXCOR treatment is
hampered by complications including thrombo-embolism,
mechanical problems and infections, requiring high surveil-
lance and intensive clinical monitoring (Figure 4,Video 1).
Conflict of Interest Statement
Dr Dellgren: Astellas Pharma Europe for an investigator-
initiated study in immunosuppression after lung transplan-
tation (the ScanCLAD study, ClinicalTrials.gov Identifier:
NCT02936505); and Abbott regarding a destination therapy
study on LVAD (the SweVAD study, Investigator initiated,
ClinicalTrials.gov Identifier: NCT02592499). All other
authors reported no conflicts of interest.
The Journal policy requires editors and reviewers to
disclose conflicts of interest and to decline handling or
reviewing manuscripts for which they may have a conflict
of interest. The editors and reviewers of this article have
no conflicts of interest.
We thank the patients who participated in the study and express
gratitude to Maria Tellin and Ewa Isaksson for their help with data
collection.
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Key Words: mechanical circulatory support, left ventricu-
lar assist device (LVAD), biventricular assist device (Bi-
VAD), Berlin Heart EXCOR system, continuous flow,
pulsatile flow
1464 The Journal of Thoracic and Cardiovascular Surgery cApril 2021
Congenital: Mechanical Circulatory Support Bartfay et al
CONG
Long term MCS
(n = 24)
Berlin Excor (n = 21)
CF-LVAD (n = 3)
- Heartware (HVAD) (n = 3)
BiVAD (n = 5)
Received intervention (n = 5)
LVAD (n = 15)
RVAD (n = 1)
Received intervention (n = 16)
Survived to transplantation (n = 3)
Explantation (n = 1)
Death on device (n = 1)
Survived to transplantation (n = 9)
Explantation (n = 7)
Death on device (n = 0)
FIGURE E1. Flow diagram of children who received long-term MCS at Sahlgrenska University Hospital during the study period. MCS, Mechanical cir-
culatory support; CF, continuous flow; LVAD, left ventricular assist device; HVAD, Heartware ventricular assist device; BiVAD, biventricular assist device;
RVAD, right ventricular assist device.
Long term MCS
(n = 96)
Berlin Excor (n = 29)
TAH (Syncardia)
(n = 2)
BiVAD (n = 28)
Received intervention (n = 28)
LVAD (n = 1)
Received intervention (n = 1)
Survived to transplantation (n = 23)
Explantation (n = 1)
Death on device (n = 4)
Survived to transplantation (n = 1)
CF-LVAD (n = 65)
- Ventrassist (n = 2)
- Heart mate II (n = 40)
- Heart mate III (n = 23)
FIGURE E2. Flow diagram of adults who received long-term MCS at Sahlgrenska University Hospital during the study period. MCS, Mechanical circu-
latory support; TAH, total artificial heart; CF, continuous flow; LVAD, left ventricular assist device; BiVAD, biventricular assist device.
The Journal of Thoracic and Cardiovascular Surgery cVolume 161, Number 4 1464.e1
Bartfay et al Congenital: Mechanical Circulatory Support
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0
20
40
60
80
100
Survival probability (%)
0
B
21
29
20
23
16
22
14
18
13
16
13
14
12
11
10
9
8
4
INTERMACS > 1
INTERMACS = 1
No. at risk
123
P = .2
4
Time (years)
5678
0
20
40
60
80
100
Survival probability
free from major stroke (%)
0
C
21
29
19
19
15
19
14
18
13
16
13
14
12
11
10
9
8
4
INTERMACS > 1
INTERMACS = 1
No. at risk
123
P = .2
4
Time (years)
5678
0
A
20
40
60
Probability for HTx/weaning (%)
80
100
0 100 200
P = .5
Time (days)
300
INTERMACS = 1 INTERMACS > 1
FIGURE E3. Time on EXCOR device and survival for patient with different INTERMACS profiles. A, Time on EXCOR to HTx or weaning for patients in
INTERMACS ¼1 versus those in INTERMACS>1. B, Overall survival in patients in INTERMACS ¼1 versus those in INTERMACS>1. C, Survival free
from disabling stroke in patients in INTERMACS ¼1 versus those in INTERMACS>1. HTx, Heart transplantation; INTERMACS, Interagency Registry for
Mechanically Assisted Circulatory Support.
1464.e2 The Journal of Thoracic and Cardiovascular Surgery cApril 2021
Congenital: Mechanical Circulatory Support Bartfay et al
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0
20
40
P = .05
60
Survival probability (%)
80
100
0
26
24
25
18
21
17
19
13
18
11
17
10
16
7
13
6
9
3
1234
Time (years)
5
Other HF ethiology
DCM
678
Males
No. at risk
Females
C
0
20
40
P = .01
60
Survival probability
free from major stroke (%)
80
100
0
26
24
22
18
13
14
13
13
18
11
17
10
16
7
13
6
9
3
1234
Time (years)
5
Other HF ethiology
DCM
678
Males
No. at risk
Females
D
0
20
40
P = .5
60
Survival probability (%)
80
100
0
28
22
25
17
21
14
19
13
18
11
17
10
15
7
8
4
7
8
1234
Time (years)
5678
Males
No. at risk
Females
A
0
20
40
P = .2
60
Survival probability
free from major stroke (%)
80
100
0
28
22
25
17
21
14
19
13
18
11
17
10
15
7
8
4
7
8
1234
Time (years)
5678
Males
No. at risk
Females
B
Females
Males
Females
Males
FIGURE E4. Overall survival probability and survival free from stroke for patients throughout and after EXCOR treatment during 8 years of follow-up. A,
Overall survival in male versus female patients; B, survival free from disabling stroke in male versus female patients; C, overall survival in patients with
DCM versus other HF etiology; and D, overall survival in patients with DCM versus other heart failure etiology. DCM, Dilated cardiomyopathy; HF, heart
failure.
The Journal of Thoracic and Cardiovascular Surgery cVolume 161, Number 4 1464.e3
Bartfay et al Congenital: Mechanical Circulatory Support
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TABLE E1. Risk factors for postoperative right ventricular failure (the presence of 2 or more risk factors favored BiVAD implantation)
1 TAPSE<0.72 cm
2 RVEDD/LVEDD >0.72
3 CVP>16 mm Hg
4 MPAP–RAP<10 mm Hg (or SPAP-DPAP/CVP<0.5)
5 CVP/PCWP>0.63
6 RVSWI<300 mm Hg 3mL/m
2
7 Bilirubin>34 mmol/L
TAPSE, tricuspid annular plane systolic excursion; RVEDD, right ventricular end-diastolic diameter; LVEDD, left ventricular end-diastolic diameter; CVP, central venous pres-
sure; MPAP, mean pulmonary arterial pressure; RPAP, right pulmonary artery pressure; SPAP, systolic pulmonary artery pressure; DPAP, diastolic pulmonary artery pressure;
PCWP, pulmonary capillary wedge pressure; RVSWI, right ventricular stroke work index.
TABLE E2. Patients with congenital heart diseases who received an EXCOR device in the present study
Patient Age Diagnosis Type of VAD
1 Adult Senning op (transposition) Univentricular
2 Adult Congenital aortic stenosis, LV elastosis, severe PH Biventricular
3 Pediatric HLHS, Norwood surgery þGlenn VAD to morphologic RV Univentricular
4 Pediatric Congenital aortic stenosis, LV elastosis Univentricular
5 Pediatric Congenital aortic vitium. Several surgical procedures, severe LV failure Univentricular
6 Pediatric cc-TGA, VAD to morphologic RV Univentricular
7 Pediatric ALCAPA. Severe LV failure postoperatively Univentricular
8 Pediatric ALCAPA. Severe LV failure postoperatively Univentricular
VAD, Ventricular assist device; LV, left ventricular; PH, pulmonary hypertension; HLHS, hypoplastic left heart syndrome; RV, right ventricular; cc-TGA, congenitally corrected
transposition of the great arteries; ALCAPA, anomalous left coronary artery from the pulmonary artery.
1464.e4 The Journal of Thoracic and Cardiovascular Surgery cApril 2021
Congenital: Mechanical Circulatory Support Bartfay et al
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