scholarly journals Left Ventricular Myocardial Septal Pacing in Close Proximity to LBB Does Not Prolong the Duration of the Left Ventricular Lateral Wall Depolarization Compared to LBB Pacing

2021 ◽  
Vol 8 ◽  
Author(s):  
Karol Curila ◽  
Pavel Jurak ◽  
Kevin Vernooy ◽  
Marek Jastrzebski ◽  
Petr Waldauf ◽  
...  

Background: Three different ventricular capture types are observed during left bundle branch pacing (LBBp). They are selective LBB pacing (sLBBp), non-selective LBB pacing (nsLBBp), and myocardial left septal pacing transiting from nsLBBp while decreasing the pacing output (LVSP). Study aimed to compare differences in ventricular depolarization between these captures using ultra-high-frequency electrocardiography (UHF-ECG).Methods: Using decremental pacing voltage output, we identified and studied nsLBBp, sLBBp, and LVSP in patients with bradycardia. Timing of ventricular activations in precordial leads was displayed using UHF-ECGs, and electrical dyssynchrony (e-DYS) was calculated as the difference between the first and last activation. The durations of local depolarizations (Vd) were determined as the width of the UHF-QRS complex at 50% of its amplitude.Results: In 57 consecutive patients, data were collected during nsLBBp (n = 57), LVSP (n = 34), and sLBBp (n = 23). Interventricular dyssynchrony (e-DYS) was significantly lower during LVSP −16 ms (−21; −11), than nsLBBp −24 ms (−28; −20) and sLBBp −31 ms (−36; −25). LVSP had the same V1d-V8d as nsLBBp and sLBBp except for V3d, which during LVSP was shorter than sLBBp; the mean difference −9 ms (−16; −1), p = 0.01. LVSP caused less interventricular dyssynchrony and the same or better local depolarization durations than nsLBBp and sLBBp irrespective of QRS morphology during spontaneous rhythm or paced QRS axis.Conclusions: In patients with bradycardia, LVSP in close proximity to LBB resulted in better interventricular synchrony than nsLBBp and sLBBp and did not significantly prolong depolarization of the left ventricular lateral wall.

EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
K Curila ◽  
P Jurak ◽  
P Waldauf ◽  
J Halamek ◽  
J Karch ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): This paper was supported by the Charles University Research Centre program No. UNCE/MED/002 and 260530/SVV/2020 Background Direct and indirect pacing of the left bundle branch are novel pacing techniques preserving LV synchrony. Aim of the study was to compare differences in ventricular activation between them using an UHF-ECG. Methods The left septal lead placement was done in 68 patients with bradycardia. Four distinct ventricular captures were described; nonselective LBBp (nsLBBp), selective LBBp (sLBBp), paraLBBp and left bundle branch area capture (LBBap). The timings of local ventricular activations and local depolarization durations were displayed by the UHF-ECG. e-DYS was calculated as a difference between the first and last activation. Results There were 35 nsLBBp, 21 paraLBBp, 12 sLBBp and 96 LBBap obtained in 68 patients.  The nsLBBp compared to LBBap caused worse interventricular synchrony (e-DYS -23 ms (-28;-18) vs -12 ms (-17;-8), p < 0.001), but improved LV lateral wall depolarization duration. The sLBBp, nsLBBp and paraLBBp differed in e-DYS; -31 ms (-38;-24) vs -23 ms (-28;-17) vs -13 ms (-20;-7), p < 0.01 between each of them. Their left ventricular depolarization durations were the same, but they were longer when pacing resulted in the left axis deviation. If the direct capture of the LBB was not confirmed (LBBap), LV depolarization duration was deteriorated irrespective of the QSR morphology in the V1 or RWPT in the V5. Examples of UHF-ECG maps during LBBap, paraLBBp and nsLBBp are shown in Figure 1. Conclusions The direct capture of the left bundle branch deteriorates interventriclar synchrony but improves the depolarization duration of the left ventricular lateral wall compared to left ventricular myocardial septal pacing. Abstract Figure 1


2021 ◽  
Vol 10 (4) ◽  
pp. 822
Author(s):  
Luuk I.B. Heckman ◽  
Justin G.L.M. Luermans ◽  
Karol Curila ◽  
Antonius M.W. Van Stipdonk ◽  
Sjoerd Westra ◽  
...  

Background: Left bundle branch area pacing (LBBAP) has recently been introduced as a novel physiological pacing strategy. Within LBBAP, distinction is made between left bundle branch pacing (LBBP) and left ventricular septal pacing (LVSP, no left bundle capture). Objective: To investigate acute electrophysiological effects of LBBP and LVSP as compared to intrinsic ventricular conduction. Methods: Fifty patients with normal cardiac function and pacemaker indication for bradycardia underwent LBBAP. Electrocardiography (ECG) characteristics were evaluated during pacing at various depths within the septum: starting at the right ventricular (RV) side of the septum: the last position with QS morphology, the first position with r’ morphology, LVSP and—in patients where left bundle branch (LBB) capture was achieved—LBBP. From the ECG’s QRS duration and QRS morphology in lead V1, the stimulus- left ventricular activation time left ventricular activation time (LVAT) interval were measured. After conversion of the ECG into vectorcardiogram (VCG) (Kors conversion matrix), QRS area and QRS vector in transverse plane (Azimuth) were determined. Results: QRS area significantly decreased from 82 ± 29 µVs during RV septal pacing (RVSP) to 46 ± 12 µVs during LVSP. In the subgroup where LBB capture was achieved (n = 31), QRS area significantly decreased from 46 ± 17 µVs during LVSP to 38 ± 15 µVs during LBBP, while LVAT was not significantly different between LVSP and LBBP. In patients with normal ventricular activation and narrow QRS, QRS area during LBBP was not significantly different from that during intrinsic activation (37 ± 16 vs. 35 ± 19 µVs, respectively). The Azimuth significantly changed from RVSP (−46 ± 33°) to LVSP (19 ± 16°) and LBBP (−22 ± 14°). The Azimuth during both LVSP and LBBP were not significantly different from normal ventricular activation. QRS area and LVAT correlated moderately (Spearman’s R = 0.58). Conclusions: ECG and VCG indices demonstrate that both LVSP and LBBP improve ventricular dyssynchrony considerably as compared to RVSP, to values close to normal ventricular activation. LBBP seems to result in a small, but significant, improvement in ventricular synchrony as compared to LVSP.


1962 ◽  
Vol 203 (6) ◽  
pp. 1141-1144 ◽  
Author(s):  
Jay M. Levy ◽  
Emmanuel Mesel ◽  
Abraham M. Rudolph

Simultaneous right and left ventricular stroke volumes were measured with electromagnetic flow probes in open-chest, anesthetized dogs. Atrial ectopic beats with normal ventricular depolarization produced differences between right and left ventricular stroke output, although the right and left ventricular pressures were proportionately reduced to an equal extent. This imbalance in volume ejected was a result of the differences in diastolic level, related to peak systolic pressure, in the aorta compared with pulmonary artery. With ventricular ectopic beats, the stimulated ventricle failed to develop the same percentage of control pressure as did the contralateral ventricle. The difference between aortic and pulmonary flow was thus less marked with right ventricular ectopic beats, and exaggerated with left ventricular ectopic beats.


Heart Rhythm ◽  
2021 ◽  
Vol 18 (8) ◽  
pp. S15-S16
Author(s):  
Karol Curila ◽  
Pavel Jurak ◽  
Marek Jastrzebski ◽  
Frits W. Prinzen ◽  
Petr Waldauf ◽  
...  

2019 ◽  
Vol 21 (2) ◽  
pp. 77-80
Author(s):  
Rezoana Ahmed ◽  
Sharmin Rahman ◽  
Shamim Momtaz Ferdousi Begum ◽  
Raihan Hussain

Objectives: Transient ischemic dilation (TID) refers to an apparent increase in the size of the left ventricular cavity on stress myocardial perfusion imaging compared to rest imaging. This study was performed to correlate the value of TID ratio in gated SPECT MPI in Coronary Artery Disease (CAD). Patients & Methods: Seventy-four suspected or known CAD patients underwent MPI performed with Tc-99m sestamibi. Single day stress - rest protocol with pharmacological stress was followed, according to established practicing protocol of NINMAS. A statistical analysis was carried out by using the Statistical Package for Social Sciences version 20.0 for Windows (SPSS Inc., Chicago, Illinois, USA). Student t-test was used for continuous variables. Chi-square test used to compare categorical data. P values <0.05 was considered as statistically significant. Results: Among 74 patients, 63(85.1%) were male and 11(14.9%) were female. The mean age found to be 53.8±10.5 years. Majority (90.5%) patients had hypertension, 45(60.8%) had diabetic mellitus and 39(52.7%) had dyslipidemia in blood lipid profile, 44(59.5%) were past smoker. The mean ejection fraction was 44.6±14.6 percent. The mean abnormal TID ratio was 1.25 ± 0.35 in patients having abnormal MPI findings and 1.03±0.21 in having normal MPI findings. The difference was statistically significant (p<0.05) between two groups. It was also observed that in three cases having normal MPI had high TID ratio.Among the patients with TID ratio >1.19, 24(64.9%) patients were in MVD group and 13(92.9%) were in SVD group. Whereas among the patients with TID ratio<1.19, 13(35.1%) were in MVD group and 1(7.1%) were in SVD group. The difference was statistically significant (P<0.05) between two groups. The mean TID ratio was 1.08±0.21 in single vessel disease and 1.24±0.26 in multiple vessel disease. The difference was also statistically significant (p<0.05) between two groups. Conclusion: This study suggests that the TID ratios could provide incremental diagnostic information to standard myocardial perfusion analysis for the identification of severe and extensive disease in patients with suspected or known CAD. Bangladesh J. Nuclear Med. 21(2): 77-80, July 2018


2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
A P Pilalidou ◽  
V K Kantartzi ◽  
C A Adamopoulos ◽  
L Z Zitiridou ◽  
M D Dimtsa ◽  
...  

Abstract Funding Acknowledgements None Background/Introduction: Calculation of the LV and RV stroke volumes (SV) with the volumetric method can be useful for assessment of valvular regurgitant volumes and intracardiac shunt ratios. However, this method often yields significant differences between the estimated LV and RV SV even in healthy subjects. We hypothesized that this discrepancy can be largely due to the assumption of LV and RV outflow tract circularity which forms the basis of 2D derived areas. Purpose To assess if the use of 3D transoesophageal (TOE) derived LVOT and RVOT areas can improve the agreement between LV and RV stroke volumes using the volumetric approach in healthy subjects with no valvular abnormality or intracardiac shunt. Methods We studied 20 patients (9 Males, age: 51 ± 19 y) submitted to TOE for various reasons, who had normal cardiac anatomy and function and good quality 3D TOE LVOT and RVOT data. Two dimensional TOE measurements of the LVOT and RVOT diameters were made in a zoomed mid oesophageal long axis and short axis view respectively; using these measurements 2D TOE LVOT and RVOT derived areas were calculated assuming circularity. In a similar way, we calculated the 2D LVOT and RVOT areas using data from transthoracic echo (TTE) for each patient. Offline analysis of the 3D TOE data allowed direct planimetry of the LVOT and RVOT areas devoid of any geometric assumptions. Finally, calculation of the 2D TTE, 2D TOE and 3D TOE LV and RV stroke volumes were performed for each patient based on the acquired data. The difference between LV and RV stroke volume (which theoretically should be around zero) for each technique and for each patient was also calculated. Results The mean LV and RV SV for the whole cohort, did not differ significantly within each method: 2D-TTE. However, the mean absolute difference between LV and RV stoke volumes for each technique was significantly lower with the use of 3D TOE compared to both 2D TTE and 2D TOE. Mean values and dispersion of absolute differences for each method are shown in Figure 1. Conclusions Compared to 2D, use of direct 3D TOE RVOT and LVOT planimetry yielded significantly less difference between RV and LV stroke volumes in healthy individuals. This finding can have potential clinical implications for more accurate assessment of valvular regurgitant volumes or intracardiac shunts. The mean absolute difference LV-RV Absolute mean defference between LV and RV 95%ΔΕ F(2.38) p-value TTE 2D 18,65 ± 11,72 (13,2-24,1) 8.63 0.001 TOE 2D 13,45 ± 12,44 (7,6-19.3) 8.63 0.001 TOE 3D 6,45 ± 3,62 (4,8-8,1) 8.63 0.001 Abstract P1559 Figure. Bland Altaman Analysis


EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
LIB Heckman ◽  
JGK Luermans ◽  
K Curila ◽  
AMW Van Stipdonk ◽  
S Westra ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: None. Background Left bundle branch area pacing (LBBAP) has recently been introduced as a novel physiological pacing strategy. Within LBBAP, distinction is made between left bundle branch pacing (LBBP) and left ventricular septal pacing (LVSP, no left bundle capture). Objective To compare acute electrocardiographic (ECG) and vectorcardiographic (VCG) effects of LBBP and LVSP as compared to intrinsic conduction. Methods In 50 patients with normal cardiac function and pacemaker indication for bradycardia, ECG characteristics of LBBP and LVSP were evaluated during RVSP and pacing at various depths in the septum: starting at the RV side of the septum: the last position with QS morphology, the first position with r’ morphology, LVSP and – in patients where LBB capture was achieved – LBBP. From the ECG’s QRS duration and QRS morphology in V1, and the stimulus-LVAT interval were measured. After conversion of the ECG into VCG (Kors conversion matrix), QRS area was calculated. Results In LVSP, QRS area significantly decreased from 82 ± 29 µVs during RVSP to 46 ± 12 µVs during LVSP. In patients where LBB capture was achieved QRS area significantly decreased from 78 ± 23 µVs to 38 ± 15 µVs in LBBP. In patients with LBB capture, QRS area was significantly smaller during LBBP compared to LVSP (figure A), but LVAT was not significantly different (figure B, p = 0.138). In patients with normal ventricular activation where LBBP was achieved (n = 20), QRS area was significantly larger during LVSP (48 ± 17) compared to LBBP (37 ± 16), the latter being not significantly different from normal intrinsic ventricular activation (35 ± 19 µVs). Conclusions ECG and VCG indices demonstrate that ventricular dyssynchrony is comparable but slightly more synchronous during LBBP compared to LVSP. Abstract Figure. QRS area and S-LVAT in LVSP and LBBP


2019 ◽  
Vol 50 (4) ◽  
pp. 562-578 ◽  
Author(s):  
Dawna Duff

Purpose Vocabulary intervention can improve comprehension of texts containing taught words, but it is unclear if all middle school readers get this benefit. This study tests 2 hypotheses about variables that predict response to vocabulary treatment on text comprehension: gains in vocabulary knowledge due to treatment and pretreatment reading comprehension scores. Method Students in Grade 6 ( N = 23) completed a 5-session intervention based on robust vocabulary instruction (RVI). Knowledge of the semantics of taught words was measured pre- and posttreatment. Participants then read 2 matched texts, 1 containing taught words (treated) and 1 not (untreated). Treated texts and taught word lists were counterbalanced across participants. The difference between text comprehension scores in treated and untreated conditions was taken as a measure of the effect of RVI on text comprehension. Results RVI resulted in significant gains in knowledge of taught words ( d RM = 2.26) and text comprehension ( d RM = 0.31). The extent of gains in vocabulary knowledge after vocabulary treatment did not predict the effect of RVI on comprehension of texts. However, untreated reading comprehension scores moderated the effect of the vocabulary treatment on text comprehension: Lower reading comprehension was associated with greater gains in text comprehension. Readers with comprehension scores below the mean experienced large gains in comprehension, but those with average/above average reading comprehension scores did not. Conclusion Vocabulary instruction had a larger effect on text comprehension for readers in Grade 6 who had lower untreated reading comprehension scores. In contrast, the amount that children learned about taught vocabulary did not predict the effect of vocabulary instruction on text comprehension. This has implications for the identification of 6th-grade students who would benefit from classroom instruction or clinical intervention targeting vocabulary knowledge.


1991 ◽  
Vol 30 (05) ◽  
pp. 183-188
Author(s):  
A. Aydrner ◽  
A. Oto ◽  
E. Oram ◽  
O. Gedik ◽  
C. F. Bekdik ◽  
...  

Left ventricular function including regional wall motion (RWM) was evaluated by 99mTc first-pass and equilibrium gated blood pool ventriculography and glycohemoglobin (HbA1c) blood levels determined by a quantitative column technique in 25 young patients with insulin-dependent diabetes mellitus without clinical evidence of heart disease, and in healthy controls matched for age and sex. Phase analysis revealed abnormal RWM in 19 of 21 diabetic patients. The mean left ventricular global ejection fraction, the mean regional ejection fraction and the mean 1/3 filling fraction were lower and the time to peak ejection, the time to peak filling and the time to peak ejection /cardiac cycle were longer in diabetics than in controls. We found high HbA1c levels in all diabetics. There was no significant difference between patients with and without retinopathy and with and without peripheral neuropathy in terms of left ventricular function and HbA1c levels.


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