Search

Aims: Three distinct septal contraction patterns typical for left bundle branch block may be assessed using echocardiography in heart failure patients scheduled for cardiac resynchronization therapy (CRT). The aim of this study was to explore the association between these septal contraction patterns and the acute haemodynamic and electrical response to biventricular pacing (BIVP) in patients undergoing CRT implantation., Methods and Results: Thirty-eight CRT candidates underwent speckle tracking echocardiography prior to device implantation. The patients were divided into two groups based on whether their septal contraction pattern was indicative of dyssynchrony (premature septal contraction followed by various amount of stretch) or not (normally timed septal contraction with minimal stretch). CRT implantation was performed under invasive left ventricular (LV) pressure monitoring and we defined acute CRT response as ≥10% increase in LV dP/dtmax. End-diastolic pressure (EDP) and QRS width served as a diastolic and electrical parameter, respectively. LV dP/dtmax improved under BIVP (737 ± 177 mmHg/s vs. 838 ± 199 mmHg/s, P < 0.001) and 26 patients (68%) were defined as acute CRT responders. Patients with premature septal contraction (n = 27) experienced acute improvement in systolic (ΔdP/dtmax: 18.3 ± 8.9%, P < 0.001), diastolic (ΔEDP: -30.6 ± 29.9%, P < 0.001) and electrical (ΔQRS width: -23.3 ± 13.2%, P < 0.001) parameters. No improvement under BIVP was observed in patients (n = 11) with normally timed septal contraction (ΔdP/dtmax: 4.0 ± 7.8%, P = 0.12; ΔEDP: -8.8 ± 38.4%, P = 0.47 and ΔQRS width: -0.9 ± 11.4%, P = 0.79)., Conclusion: Septal contraction patterns are an excellent predictor of acute CRT response. Only patients with premature septal contraction experienced acute systolic, diastolic, and electrical improvement under BIVP., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author(s) 2020. For permissions, please email: journals.permissions@oup.com.)

Aims: A difficult cardiac resynchronization therapy (CRT) implantation scenario emerges when no lateral pacing option exists. The aim of this study was to explore the effect of biventricular pacing (BIVP) on vectorcardiographic parameters in patients with a non-lateral left ventricular (LV) lead position. We hypothesized that perimeter and area reduction for both the QRS complex and T-wave would predict acute CRT response., Methods and Results: Twenty-six patients (14 ischaemic) with a mean age of 63 ± 10 years and standard CRT indication underwent device implantation with continuous LV pressure registration. The LV lead was placed in either an anterior or apical position. Biventricular pacing was performed at a rate 10% above intrinsic rhythm with acute CRT response defined as LV ΔdP/dtmax >10%. Using this criterion 12 patients were identified as acute CRT responders (responders: 16.7 ± 4.8% vs. non-responders: 1.9 ± 5.3%, P < 0.001). Vectorcardiographic assessment of the QRS complex and T-wave were performed at baseline and under BIVP. Based on the observed changes in three-dimensional area and perimeter, ΔQRS-area (responders: -46.7 ± 39.6% vs. non-responders: 1.1 ± 50.9%, P = 0.006) was considered as the preferred parameter. Receiver operating characteristic curve analysis identified -40% as the optimal cut-off value (sensitivity 67% and specificity 93%) for prediction of acute CRT response (AUC = 0.81, P < 0.01). A significant correlation was observed between LV ΔdP/dtmax and ΔQRS-area (R2 = 0.37, P = 0.001)., Conclusion: ΔQRS-area is correlated to LV ΔdP/dtmax and predicts acute CRT response in patients with a non-lateral LV lead position. Assessment of ΔQRS-area might be a useful tool for patient specific LV lead placement when no lateral pacing option exists.