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Relationship between the paced QRS duration and Q-endo delay in according to fluoroscopic segments (high, mid and low septal) and paced QRS characteristics (presence of notching in limb leads). A Q-endo delay < 50 ms, a mid fluoroscopic position and a QRS limb leads without notching (green outlined boxes) included almost the totally of QRS ≤ 160 measurements (54/61, 85.5%). F = fluoroscopic; Q-endo = delay between onset of QRS and the local bipolar activation; QRS notching = QRS notching in limb leads.
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A short paced (p) QRS duration (d) can be a marker for selecting the most appropriate RV pacing site. Although this could be achieved by continual 12-Lead ECG monitoring, such a technique is not applicable during pacemaker (PM) implantation. The purpose of this study was to validate a method for identifying the optimal site for RV septum pacing usi...
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Context 1
... the Q-endo is analyzed as a continous variable the corrected prediction of pQRSd increases up to 79.2%. In Figure 2 the correlation between Q-endo delay and pQRSd is categorized by the notching and fluoroscopic septal segment. A Q-endo delay < 50 ms, a mid fluoroscopic posi- tion and QRS limb leads without notching iden- tified the large majority of measurements (54/61, 85.5%) with QRS ≤ 160. ...
Similar publications
Introduction:
To study effects of various sites of right ventricular pacing lead implantation on left ventricular function by 2-dimensional (2D) speckle tracking for radial strain and LV dyssynchrony.
Methods:
This was retrospective prospective study. Fifteen patients each with right ventricular (RV) apical (RV apex and apical septum) and non-ap...
Citations
... To increase the likelihood of achieving a true septal position during implantation, the anatomical (fluoroscopy) criteria could be combined with ECG criteria, which have been previously suggested by others. Pastore et al. 20 showed that a delay from the QRS onset to the intracardiac signal on the RV electrode, and the absence of notching in limb leads on a paced QRS, are predictive of shorter QRS complex durations. The advantage of this technique is the use of limb leads only, however, whether the lead was in the septum or in the adjacent anterior wall (which has similar QRS durations) was not analysed. ...
The location of the pacemaker lead is based on the shape of the lead on fluoroscopy only, typically in the left and right anterior oblique positions. However, these fluoroscopy criteria are insufficient and many leads apparently considered to be in septum are in fact anchored in anterior wall. Periprocedural ECG could determine the correct lead location. The aim of the current analysis is to characterize ECG criteria associated with a correct position of the right ventricular (RV) lead in the mid-septum. Patients with indications for a pacemaker had the RV lead implanted in the apex (Group A) or mid-septum using the standard fluoroscopic criteria. The exact position of the RV lead was verified using computed tomography. Based on the findings, the mid-septal group was divided into two subgroups: (i) true septum, i.e. lead was found in the mid-septum, and (ii) false septum, i.e. lead was in the adjacent areas (anterior wall, anteroseptal groove). Paced ECGs were acquired from all patients and multiple criteria were analysed. Paced ECGs from 106 patients were analysed (27 in A, 36 in true septum, and 43 in false septum group). Group A had a significantly wider QRS, more left-deviated axis and later transition zone compared with the true septum and false septum groups. There were no differences in presence of q in lead I, or notching in inferior or lateral leads between the three groups. QRS patterns of true septum and false septum groups were similar with only one exception of the transition zone. In the multivariate model, the only ECG parameters associated with correct lead placement in the septum was an earlier transition zone (odds ratio (OR) 2.53, P = 0.001). ECGs can be easily used to differentiate apical pacing from septal or septum-close pacing. The only ECG characteristic that could help to identify true septum lead position was the transition zone in the precordial leads.
ClinicalTrials.gov identifier: NCT02412176.
... A prospective observational study studied the optimal pacing site in the right ventricular septum [10]. Overall, 304 measurements of paced QRS complex characteristics in different RVS sites were performed in (100/102 patients). ...
Background:
Right ventricular apical pacing with the resultant left ventricular dyssynchrony often leads to depressed systolic function and heart failure. This study aimed at investigating the relation between various septal locations guided by ECG and fluoroscopy and the intermediate term functional capacity of the patients.
Results:
Fifty patients who received a single lead pacemaker with assumed > 90% pacemaker dependency. Patients were randomized according to RV pacing site RV into group 1 "high septum" (n = 15), group 2 "mid septum" (n = 25), and group 3 "low septum" (n = 10) using QRS vector and duration as well as fluoroscopic parameters. Their clinical status was assessed 6 months after device implementation using 6-min walk test (6MWT). The study showed that paced QRS complex duration itself has no significant difference between the different septal pacing locations (P-value 0.675), although its combination with the paced QRS complex vector can signify the optimal pacing site and 6MWT showed a significant difference among the groups in favor of group 1; group 1 (413.3 ± 148.5), group 2 (359.8 ± 124.6), and group 3 (276.0 ± 98.5) P value 0.04.
Conclusion:
There was a significant difference found between the three septal pacing sites concerning the patient functional capacity with superiority of high septal location. By contrast, different septal sites showed no significant difference of the paced QRS complex duration. To optimize the pacing site in the septum, assessment of the paced QRS vector in leads I and III is of a great benefit especially when combined with paced QRS complex duration assessment.
... A prospective observational study studied the optimal pacing site in the right ventricular septum [10]. Overall, 304 measurements of paced QRS complex characteristics in different RVS sites were performed in (100/102 patients). ...
... Second, there is controversy about whether a higher degree of synchrony can be achieved by stimulating from points in the RV other than the apex (Da Costa et al., 2013;Pastore et al., 2013). Third, individualized programming of the atrioventricular delay (AVD) and interventricular delay (VVD) intervals is not typically performed in most patients in the normal clinical practice, and it has been primarily reserved for non CRT responders (Gras et al., 2009). ...
... The RV septal wall is an alternative location for the RV pacing lead in CRT. In this study, three different locations for the RV pacing lead were tested based on medical protocols and research works (Da Costa et al., 2013;Pastore et al., 2013). The RV septal electrode was placed in the apex (RVapex), middle septal region (RVmid) or upper region near the outflow tract (RVupper) (Figure 2A). ...
Patients suffering from heart failure and left bundle branch block show electrical ventricular dyssynchrony causing an abnormal blood pumping. Cardiac resynchronization therapy (CRT) is recommended for these patients. Patients with positive therapy response normally present QRS shortening and an increased left ventricle (LV) ejection fraction. However, around one third do not respond favorably. Therefore, optimal location of pacing leads, timing delays between leads and/or choosing related biomarkers is crucial to achieve the best possible degree of ventricular synchrony during CRT application. In this study, computational modeling is used to predict the optimal location and delay of pacing leads to improve CRT response. We use a 3D electrophysiological computational model of the heart and torso to get insight into the changes in the activation patterns obtained when the heart is paced from different regions and for different atrioventricular and interventricular delays. The model represents a heart with left bundle branch block and heart failure, and allows a detailed and accurate analysis of the electrical changes observed simultaneously in the myocardium and in the QRS complex computed in the precordial leads. Computational simulations were performed using a modified version of the O'Hara et al. action potential model, the most recent mathematical model developed for human ventricular electrophysiology. The optimal location for the pacing leads was determined by QRS maximal reduction. Additionally, the influence of Purkinje system on CRT response was assessed and correlation analysis between several parameters of the QRS was made. Simulation results showed that the right ventricle (RV) upper septum near the outflow tract is an alternative location to the RV apical lead. Furthermore, LV endocardial pacing provided better results as compared to epicardial stimulation. Finally, the time to reach the 90% of the QRS area was a good predictor of the instant at which 90% of the ventricular tissue was activated. Thus, the time to reach the 90% of the QRS area is suggested as an additional index to assess CRT effectiveness to improve biventricular synchrony.
... Using the Right Anterior Oblique fluoroscopic image can help confirm a septal and RVOT position as can a 12 lead ECG and a lateral chest radiograph. In relation to the 12 lead ECG studies have reviewed quick algorithms to help operators identify easily if the paced rhythm is suggestive of a septal origin and a negative deflection in lead one appears to be a strong predictor [12]. A lateral chest X-ray showing the RV lead with a posterior deflection again is predictive of a septal position [13]. ...
