Prediction of Interatrial and Interventricular Electromechanical Delays from P/QRS Measurements: Value for Pacemaker Timing Optimization

• Published in: Pacing and clinical electrophysiology 2008-02, Vol.31 (2), p.177-183
• Main Authors: CHIRIFE, RAUL, PASTORI, JULIO, MOSTO, HUGO, ARRASCAITE, MÓNICA, SAMBELASHVILI, ALEKSANDRE
• Format: Article
• Language: English
• Subjects: Aged; AV optimization; Cardiac Pacing, Artificial - standards; Echocardiography, Doppler; Electrocardiography; Female; Heart Conduction System - physiopathology; Humans; interatrial delay; interventricular delay; Male; Middle Aged; Predictive Value of Tests; Prospective Studies; Regression Analysis
• ISSN: 0147-8389; 1540-8159
• DOI: 10.1111/j.1540-8159.2007.00966.x

Cardiac pacing creates spurious delays between and within the cardiac chambers. These are: 1. Left atrial (LA) transport delay (ATD) either sensed (s) or paced (p), (time from right atrial P‐wave to the end of LA transport (mitral Doppler A‐wave)). 2. Interventricular delay (IVD), (time from onsets of right (RV) to left ventricular (LV) contractions). 3. P‐sense offset (PSO), (time from P‐onset to P‐detection). Thus, restoration of left heart atrioventricular (AV) synchrony can be accomplished by compensating above delays, according to a previously published equation: RAV = ATD‐IVD‐PSO, where RAV = right heart AV. Objective: To test the hypothesis that ATD could be predicted from Ps and Pp, and that interventricular delay (IVD) could be predicted from QRSp, using three‐lead surface electrocardiograms (ECGs). Methods: Thirty‐six patients aged 63.5 ± 15.5 years, 64% males, all with previously implanted DDD pacemakers, were studied by echo‐Doppler and surface ECG obtained with a pacemaker programmer. Measurements included Ps; Pp; intrinsic QRSs; and paced QRSp, ATDs, ATDp, and IVD (difference between RVp and RVs left preejection intervals, PEI). Regressions between ECG and echo‐Doppler intervals were calculated. Results: Regressions and correlation coefficients: ATD (s+p) = 0.96*P + 55 (R = 0.94, P < 0.0001); PEIp = 0.75 * QRSp + 34.8 (R = 0.89, P< 0.0001); IVD = 0.39 *QRSp – 7.9 ms (R = 0.87, P = 0.002). Conclusions: Inter‐atrial and inter‐ventricular electromechanical delays can be predicted from P‐wave and QRS durations. These measurements allow AV delay optimization in DDD and cardiac resynchronization therapy devices with no need of Doppler echocardiography.