His Resynchronization Versus Biventricular Pacing in Patients With Heart Failure and Left Bundle Branch Block

Abstract

BackgroundHis bundle pacing is a new method for delivering cardiac resynchronization therapy (CRT).ObjectivesThe authors performed a head-to-head, high-precision, acute crossover comparison between His bundle pacing and conventional biventricular CRT, measuring effects on ventricular activation and acute hemodynamic function.MethodsPatients with heart failure and left bundle branch block referred for conventional biventricular CRT were recruited. Using noninvasive epicardial electrocardiographic imaging, the authors identified patients in whom His bundle pacing shortened left ventricular activation time. In these patients, the authors compared the hemodynamic effects of His bundle pacing against biventricular pacing using a high-multiple repeated alternation protocol to minimize the effect of noise, as well as comparing effects on ventricular activation.ResultsIn 18 of 23 patients, left ventricular activation time was significantly shortened by His bundle pacing. Seventeen patients had a complete electromechanical dataset. In them, His bundle pacing was more effective at delivering ventricular resynchronization than biventricular pacing: greater reduction in QRS duration (−18.6 ms; 95% confidence interval [CI]: −31.6 to −5.7 ms; p = 0.007), left ventricular activation time (−26 ms; 95% CI: −41 to −21 ms; p = 0.002), and left ventricular dyssynchrony index (−11.2 ms; 95% CI: −16.8 to −5.6 ms; p < 0.001). His bundle pacing also produced a greater acute hemodynamic response (4.6 mm Hg; 95% CI: 0.2 to 9.1 mm Hg; p = 0.04). The incremental activation time reduction with His bundle pacing over biventricular pacing correlated with the incremental hemodynamic improvement with His bundle pacing over biventricular pacing (R = 0.70; p = 0.04).ConclusionsHis resynchronization delivers better ventricular resynchronization, and greater improvement in hemodynamic parameters, than biventricular pacing.

His bundle pacing, learning curve, procedure characteristics, safety, and feasibility: Insights from a large international observational study

“…HBP produces a narrow QRS duration and, by preserving physiological ventricular activation, may prevent the development of right ventricular pacing‐induced cardiomyopathy in patients with a bradycardia indication for pacing . Furthermore, HBP can often correct bundle branch block, resulting in a reduction in QRS duration and improvement in ventricular activation time …”

“…2 Furthermore, HBP can often correct bundle branch block, resulting in a reduction in QRS duration and improvement in ventricular activation time. 3 The HBP pioneers encountered several challenges during the early years of HBP, such as low procedural success rates and high and rising thresholds. 1 However, with the arrival of specialized delivery equipment and a more suitable pacing lead, the published HBP success rates appear to have improved.…”

Feasibility of His‐bundle pacing in patients with conduction disorders following transcatheter aortic valve replacement

“…Moreover, as illustrated in Figure 5, biventricular pacing only fuses two abnormal wavefronts, whereas HBP restores the normal intrinsic activation leading to less dyssynchrony. Indeed in a recent study by Arnold et al, 23 using noninvasive epicardial electrocardiographic imaging, it was shown that HBP was more effective at delivering ventricular resynchronization and produced greater acute hemodynamic benefit as compared to biventricular pacing. In the recent context of the Partner III 5 and Evolut low risk trials, 4 which included patients with lower risk, the search for better pacing solutions in this population has therefore become crucial.…”

Additional benefits of nonconventional modalities of cardiac resynchronization therapy using His bundle pacing

“…HBP has been studied by some authors as an alternative to conventional CRT 30–34 and by others in conjunction with CS pacing 35,36 . In an acute hemodynamic study, His resynchronization delivered better ventricular resynchronization and greater improvement in hemodynamic parameters than biventricular pacing 31 . Two small randomized trials comparing HBP alone with conventional CRT did not show a significant clinical benefit of HBP alone vs conventional CRT 32,33 .…”