Characteristic of R-wave peak time and its value in differential diagnosis of wide QRS complex tachycardias

Objective This study was to clarify the characteristic of R-wave peak time(RWPT) in multi-chamber ventricular pacing model, to verify its value in differential diagnosis of wide QRS complex tachycardias. Methods Thirty-two patients with tachycardias underwent multi-chamber ventricular pacing after radiofrequency catheter ablation (RFCA) procedure, and 164 pacing electrocardiogram(ECG) were recorded.The RWPT (D Ⅱ) were measured by two experienced electrophysiologist with double-blind method. Results The RWPT were≥50 ms in 152 ECG (92.7%), the RWPT were <50 ms in 12 ECG.The RWPT were(91.4±13.6)ms when paced at high right ventricular septum, the RWPT were (80.2±12.8)ms when paced at middle right ventricular septum, the RWPT were (54.6±15.5)ms when paced at left ventricular freewall group (51.3±9.5)ms and (54.6±15.5)ms at left ventricular base part. Conclusion RWPT≥50 ms is a simple, fast, effective criterion in distinguishing ventricular tachycardias from supraventricular tachycardia in patients with wide QRS complex tachycardia, especially origin from right ventricular septum, right ventricular inflow tract areas. Key words: Tachycardia; R-wave peak time; Ventricular arrhythmia; Differential diagnosis