Radial left ventricular dyssynchrony by speckle tracking in apical versus non apical right ventricular pacing- evidence of dyssynchrony on medium term follow up

Abstract

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-apical (mid septal and low right ventricular outflow tract [RVOT]) were programmed to obtain 100% ventricular pacing for evaluation by echo. Location and orientation of lead tip was noted and archived by fluoroscopy. Electrocardiography (ECG) was archived and 2D echo radial dyssynchrony was calculated. Results: The baseline data was similar between two groups. Intraventricular dyssynchrony was significantly more in apical location as compared to non-apical location (radial dyssynchrony: 108.2 ± 50.2 vs. 50.5 ± 24, P < 0.001; septal to posterior wall delay [SLWD] 63.5 ± 27.5 vs. 34 ± 10.7, P < 0.001, SPWD 112.5 ± 58.1 vs. 62.7 ± 12.1, P = 0.003). The left ventricular ejection fraction was decreased more in apical location than non apical location. Interventricular dyssynchrony was more in apical group but was not statistically significant. The QRS duration, QTc and lead thresholds were higher in apical group but not statistically significant. Conclusion: Pacing in non apical location (RV mid septum or low RVOT) is associated with less dyssynchrony by specific measures like 2D radial strain and correlates with better ventricular function in long term.

Comparison of ventricular synchrony in children with left bundle branch area pacing and right ventricular septal pacing

“…The effects of right ventricular septal pacing in terms of maintaining ventricular synchrony and cardiac function are still controversial. [13][14][15][16][17][18] With the rapid development of technology, many studies have confirmed the advantage of left bundle branch area pacing. Studies proved that left bundle branch area pacing produces narrower-paced QRS duration and better echocardiographic cardiac function than does right ventricular septal pacing.…”

Anatomical context of left anterior descending artery and right ventricular lead implanted apparently in the midseptal position - Case report

“…Již po mnoho let je známo, že apikální pravokomorová stimulace může vést k indukci systolické dysfunkce levé komory (LK) a k rozvoji manifestního srdečního selhání. Patofyziologickým podkladem je nefyziologická aktivace kontrakce z hrotové oblasti vedoucí k inter-a intraventrikulární dyssynchronii, remodelaci LK a levé síně (LS) a možnému vzniku fi brilace síní [1][2][3][4]. Stimulací indukova-ná dysfunkce LK se může vyskytnout až u 50 % pacientů plně nebo částečně závislých na pacingu.…”

“…Provedené vyšetření prokázalo, že elektroda není ve skutečnosti zavedena do midsepta, ale do přední stěny PK (v anteroseptálním žlábku) a že hrot elektrody je v těsné vzdálenosti, tedy méně než 5 mm, od RIA. Následná kontrola rametry inter-a intraventrikulární dyssynchronie) během septální stimulace ve srovnání s apikální stimulací [3,8,10].…”

Can QRS morphology be used to differentiate between true septal vs. apparently septal lead placement? An analysis of ECG of real mid-septal, apparent mid-septal, and apical pacing

“… 5–9 However, short term, echocardiographic parameters of synchronization and related QRS duration were significantly better during septal stimulation compared to apical stimulation. 3 , 8 , 10 In one randomized study of patients with reduced ejection fraction (<45%), septal pacing was associated with better preservation of systolic function compared to apical pacing. 10 …”