VAI TRÒ CỦA KHOẢNG AH KHI TẠO NHỊP NHĨ CÙNG TẦN SỐ VỚI CƠN TIM NHANH TRONG CHẨN ĐOÁN XÁC ĐỊNH CƠN TIM NHANH DO VÒNG VÀO LẠI NÚT NHĨ THẤT

Abstract

Objectives: To investigate the AH interval during supraventricular tachycardia and during atrial pacing at the tachycardia cycle length to understand the role of the differences in AH intervals in confirming the diagnosis of atrioventricular nodal reentry tachycardia. Methods: 41 patients diagnosed with supraventricular tachycardia who underwent electrophysiology studies to confirm the diagnosis followed by successful RF treatment at the Vietnam Heart Institute - Bach Mai Hospital from July 2022 to October 2023. All patients underwent electrophysiology studies and programmed heart stimulation to induce supraventricular tachycardia. After confirming the diagnosis of the tachycardia mechanism, atrial pacing maneuver were performed at the same cycle length as the tachycardia, measuring AH intervals during tachycardia and during atrial pacing. These intervals were recorded on the electrogram of the His bundle. Results: The ∆AH index is valuable in differentiating between AVNRT and the group of AT + AVRT, with an area under the curve of 1. The selected cutoff point is 44.5ms, with sensitivity and specificity both at 100%.