Non-invasive hemodynamic determination of patient-specific optimal pacing mode in cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) devices have multiple programmable pacing parameters. The purpose of this study was to determine the best pacing mode, i.e., associated with the greatest acute hemodynamic response, in each patient.

Patients in sinus rhythm and intact atrioventricular conduction were included within 3 months of implantation of devices featuring SyncAV and multipoint pacing (MPP) algorithms. The effect of nominal biventricular pacing using the latest activated electrode (BiV-Late), optimized atrioventricular delay (AVD), nominal and optimized SyncAV, and anatomical MPP was determined by non-invasive measurement of systolic blood pressure (SBP). CRT response was defined as SBP increase > 10% relative to baseline.

Thirty patients with left bundle branch block (LBBB) were included. BiV-Late increased SBP compared to intrinsic rhythm (128 ± 21 mmHg vs. 121 ± 22 mmHg, p = 0.0002). The best pacing mode further increased SBP to 140 ± 19 mmHg (p < 0.0001 vs. BiV-Late). The proportion of CRT responders increased from 40% with BiV-Late to 80% with the best pacing mode (p = 0.0005). Compared to BiV-Late, optimized AVD and optimized SyncAV increased SBP (to 134 ± 21 mmHg, p = 0.004, and 133 ± 20 mmHg, p = 0.0003, respectively), but nominal SyncAV and MPP did not. The best pacing mode was variable between patients and was different from nominal BiV-Late in 28 (93%) patients. Optimized AVD was the most frequent best mode, in 14 (47%) patients.

In patients with LBBB, the best pacing mode was patient-specific and doubled the magnitude of acute hemodynamic response and the proportion of acute CRT responders compared to nominal BiV-Late pacing.

ClinicalTrials.gov : NCT03779802.