Figure 1 - uploaded by Andreas Kjaer
Content may be subject to copyright.
Left ventriculogram. A Diastole; B systole. Images demonstrated systolic dysfunction (ejection fraction = 30%) with akinesis of the apical and midventricular segments in the acute phase of takotsubo cardiomyopathy.
Source publication
. She wastreated acutely with furosemide and nitrates because ofpulmonary oedema and transferred to a tertiary hospitalfor acute coronary angiography (CAG). Owing to mildanemia of unknown origin no anti-thrombotic treatmentwas given before transportation. Acute CAG performed4 hours after chest pain onset revealed coronary arterieswithout relevant s...
Citations
... These changes completely disappeared after 3 months. However, in a study done by Hasbak et al. using PET [173], a decrease in myocardial blood flow in the apical region of the heart could not be detected. Perfusion in the apex region of the heart remained within the normal range, and increased in the basal regions [173]. ...
... However, in a study done by Hasbak et al. using PET [173], a decrease in myocardial blood flow in the apical region of the heart could not be detected. Perfusion in the apex region of the heart remained within the normal range, and increased in the basal regions [173]. Later on, the same group demonstrated in 25 patients that myocardial beds according to PET data with 13 N-ammonium or 82 Rb were unchanged in the apical and midventricular regions and increased in basal regions [174]. ...
The purpose of the review is the analysis of clinical and experimental data on the etiology and pathogenesis of takotsubo syndrome (TS). TS is characterized by contractile dysfunction, which usually affects the apical region of the heart, lack of coronary artery obstruction, moderate increase in myocardial necrosis markers, prolonged QTc interval (in 50% of patients), sometimes elevation of ST segment (in 19% of patients), increase N-Terminal Pro-B-Type Natriuretic Peptide level, microvascular dysfunction, sometimes spasm of the epicardial coronary arteries (in 10% of patients), myocardial edema, and life-threatening ventricular arrhythmias (in 11% of patients). Stress cardiomyopathy is a rare disease, it is observed in 0.6 - 2.5% of patients with acute coronary syndrome. The occurrence of takotsubo syndrome is 9 times higher in women, who are aged 60-70 years old , than in men. The hospital mortality among patients with TS corresponds to 3.5% - 12%. In many patients with TS, but not in all, physical or emotional stress precedes the disease. Many patients with TS, but not all, have neurological or mental illnesses. The level of catecholamines is increased in patients with TS, therefore, the occurrence of TS is associated with the excessive activation of the adrenergic system. The negative inotropic effect of catecholamines is associated with the activation of β2 adrenergic receptors. An important role of the adrenergic system in the pathogenesis of TS is confirmed by studies which were performed using 125I-metaiodobenzylguanidine (125I –MIBG). TS causes edema and inflammation of the myocardium. The inflammatory response in TS is systemic. TS causes impaired coronary microcirculation and reduces coronary reserve. There is reason to believe that an increase in blood viscosity may play an important role in the pathogenesis of microcirculatory dysfunction in patients with TS. Epicardial coronary artery spasm is not obligatory for the occurrence of TS. Cortisol, endothelin-1 and microRNAs are challengers for the role of TS triggers. A decrease in estrogen levels is a factor contributing to the onset of TS. The central nervous system appears to play an important role in the pathogenesis of TS.
... Subsequent myocardial perfusion and metabolic imaging studies provided additional support to the concept of myocardial stunning in Takotsubo cardiomyopathy. Given the transient nature of myocardial ischemia as a consequence of coronary artery occlusion and reperfusion, such as coronary vasospasm, myocardial perfusion tends to be normal or only minimally decreased (likely representing partial volume effect from regional dysfunction) in Takotsubo cardiomyopathy patients studied both with single-photon [7] and positron emission tomography [8]. Regarding regional metabolic alterations, it has been well established in both experimental models and in human subjects that regional myocardial metabolism (fatty acid or glucose) is transiently decreased in the acute phase of myocardial ischemia. ...
Purpose of review:
The purpose of this review is to explore the pathophysiology of Takotsubo cardiomyopathy by appraising the interplay between myocardial perfusion, function, metabolism, and, particularly, sympathetic innervation.
Recent findings:
A number of hypotheses have been proposed to explain the pathogenesis of Takotsubo cardiomyopathy, which include (1) catecholamine cardiac toxicity, (2) myocardial sympathetic innervation disruption, (3) coronary vasospasm, (4) myocardial microvascular dysfunction, and (5) aborted myocardial infarction. These proposals are primarily derived from findings of nuclear myocardial perfusion, metabolism, and cardiac sympathetic innervation imaging. Although data in the literature are not necessarily uniform, the two most plausible working postulates for explaining the phenomenon are (1) regional myocardial stunning (due to coronary vasospasm, microvascular dysfunction, or aborted myocardial infarction) and (2) cardiac sympathetic innervation disruption or toxicity. Current data suggest that disturbances of both coronary circulation and neural innervation are associated with the Takotsubo cardiomyopathy: myocardial stunning from transient ischemic attack and sympathetic innervation disruption. It remains to be determined, however, whether the observed leading mechanistic explanations that have gained momentum are merely the sequelae of the disease rather than its primary etiology.
... Quantitative evaluation without normalization to maximum tracer uptake is desirable, as it may help to recognize patients with widespread flow reduction from a normal variance of tracer uptake [11,31]. In diseases such as Takotsubo cardiomyopathy, we recently demonstrated that what was initially interpreted, using semiquantitative MPI, as hypoperfusion of the apical region with normal basal perfusion, turned out to be normal apical perfusion with hyperperfusion of the basal part when using quantitative 82 Rb PET [36][37][38]. This also underscores how quantitative MPI can lead to new insight into pathophysiology mechanisms in cardiovascular disease. ...
Positron emission tomography (PET) allows assessment of myocardial blood flow in absolute terms (ml/min/g). Quantification of myocardial blood flow (MBF) and myocardial flow reserve (MFR) extend the scope of conventional semi-quantitative myocardial perfusion imaging (MPI): e.g. in 1) identification of the extent of a multivessel coronary artery disease (CAD) burden, 2) patients with balanced 3-vessel CAD, 3) patients with subclinical CAD, and 4) patients with regional flow variance, despite of a high global MFR. A more accurate assessment of the ischemic burden in patients with intermediate pretest probability of CAD can support the clinical decision-making in treatment of CAD patients as a complementary tool to the invasive coronary angiography (CAG). Recently, several studies have proven Rubidium-82 ((82)Rb) PET's long-term prognostic value by a significant association between compromised global MFR and major adverse cardiovascular events (MACE), and together with new diagnostic possibilities from measuring the longitudinal myocardial perfusion gradient, cardiac (82)Rb PET faces a promising clinical future. This article reviews current evidence on quantitative (82)Rb PET's ability to diagnose and risk stratify CAD patients, while assessing the potential of the modality in clinical practice.
... We have previously shown in case reports that abnormal LV flow distribution represents basal region/nTA hyperperfusion, whereas the TA/apical/midventricular region appears normoperfused. 38,39 The present study investigates and confirms these findings in a larger number of patients. Basal hyperperfusion could be explained as physiological hyperaemia to meet regionally increased metabolic requirements as basal contractility increases to compensate the failing heart. ...
Aims Takotsubo cardiomyopathy (TTC) is characterized by acute completely reversible regional left ventricle (LV) akinesia and decreased tracer uptake in the akinetic region on semi-quantitative perfusion imaging. The latter may be due to normoperfusion of the akinetic mid/apical area and basal hyperperfusion. Our aim was to examine abnormalities of perfusion in TTC, and we hypothesized that basal hyperperfusion is the primary perfusion abnormality in the acute state.
Method and results Twenty-five patients were diagnosed with TTC due to (i) acute onset of symptoms, (ii) typical apical ballooning, (iii) absence of significant coronary disease, and (iv) complete remission on 4-month follow-up. The patients underwent coronary angiography (CAG), echocardiography, cardiac magnetic resonance imaging (CMR), and 13NH3/82Rb positron emission tomography (PET) in the acute state and—except CAG—on follow-up. Patients initially had severe heart failure, mid/apical oedema but no infarction, and a rise in cardiac biomarkers. On initial perfusion PET imaging, eight patients appeared to have normal, whereas 17 patients had impaired LV perfusion. In the latter, flow in the basal region was increased in the acute state (1.5 ± 0.1 vs. 1.2 ± 0.1 mL/g/minRPP−corrected, P < 0.01), whereas midventricular (1.7 ± 0.1 vs. 1.6 ± 0.1 mL/g/minRPP−corrected, P = 0.21) and apical (1.4 ± 0.1 vs. 1.5 ± 0.1 mL/g/minRPP−corrected, P = 0.36) flow was unchanged between acute and follow-up, and within normal range.
Conclusion Our results suggest an abnormal LV perfusion distribution in the acute state of TTC with basal hyperperfusion and a normoperfused akinetic region. The proportion of patients without visualized perfusion abnormalities in the acute state may represent a subgroup with fast remission.
... Serial cardiac 82 rubidium PET and 201 Thallium PET [82] as well as quantification of microcirculatory disturbance with rest & hyperaemic myocardial blood flow (MBF) using 82rubidium PET [104] and CFR using 13 nitrogen PET [105] demonstrate a reversible apical and mid plane dysfunction with a transient fixed metabolic-perfusion mismatch during acute phase of TC. These abnormalities do not correspond to the territory of a single coronary artery distribution. ...
... The apparent perfusion defect can also be explained by hyperperfusion of the basilar, contracting myocardium, and normoperfusion of the akinetic area; a phenomenon that we have previously described casuistically [31,32]. However, this needs to be characterized further in a larger study. ...
In patients with heart failure (HF) due to coronary disease, a combined evaluation of perfusion and glucose metabolism by cardiac single photon emission computed tomography (SPECT)/positron emission tomography (PET) can be used to distinguish viable from non-viable myocardium, and current guidelines recommend cardiac SPECT and fluorodeoxyglucose (FDG) PET for viability assessment. Takotsubo cardiomyopathy (TTC) is a disease characterized by acute but reversible HF leaving no scarring. To explore how robust the semi-quantitative viability criteria used in cardiac SPECT and FDG PET stands their ground in a population with TTC. From 1 September 2009 to 1 October 2012, 24 patients suspected of TTC were enrolled in a multimodality cardiac imaging research project. Echocardiography, (99m)Tc SPECT, and (18)F FDG PET were performed during the acute admission and at follow-up 4 months later. Nineteen patients had a final diagnosis of TTC consistent with Mayo Clinic Diagnostic Criteria. Three of these patients were excluded from further analysis, since wall motion abnormalities were not persistent at the time of nuclear imaging. The remaining sixteen patients exhibited a distinct pattern with HF, "apical ballooning" and a perfusion-metabolism defect in the midventricular/apical region. When viability criteria were applied, they identified significant scarring/limited hibernation in the akinetic part of the left ventricle. However, full recovery was found in all TTC patients on follow-up. Using the current guideline-endorsed viability criteria for semiquantitative cardiac SPECT and FDG PET, these modalities failed to demonstrate the presence of viability in the acute state of TTC.
... 2 In this case, contractility and flow is also closely related: The hypocontractility, in the apical and slightly increased contractility in the basal region (as seen on the second MRI), is apparently enough to generate a perfusion pattern as we have previously described in a takotsubo patient in the presence of apical ballooning: Preserved flow in the apical and hyperaemia in the basal, hypercontractile region of the ventricle. 3 However, the observed apical perfusion defect may also partly be due to the partial volume effect, where lack of apical systolic thickening produces an apparent perfusion defect compared to basal regions that demonstrate systolic thickening. Figure 1. ...
Since the turn of the millennium, PET/CT devices evolved as the first generation of hybrid imaging systems integrating nuclear and radiological imaging from a valuable research tool into a clinically useful and accepted technique. These innovative devices combined morphological and metabolic-functional information in an elegant way and reached widespread distribution. Therefore, it seemed quite obvious to develop a PET/MR system. However, the technical hurdles for this kind of integration were for physic’s reasons much higher – but were finally solved: for more than 2 years, integrated whole-body systems are now available and, in view of the success of PET/CT, the expectations are high that PET/MR provides an actual clinical benefit. MRI’s advantage of an excellent soft tissue contrast and the capability of functional imaging at the molecular level by PET should have the potential to create a unique multimodality imaging. However, PET/MR in general and in cardiac imaging in particular needs to demonstrate its suitability in everyday clinical practice. In this review we give an overview of the requirements and features of this new hybrid imaging system and provide an outlook based on clinical examples, in which areas PET/MR could potentially find a place in the armamentarium of cardiac imaging.
