Characteristics of patients with atrial flutter and spontaneous 1:1 atrioventricular conduction with and without anti-arrhythmic drug treatment

AbstractAtrial flutter (AFL) is a large reentrant circuit located in the right atrium. Anti-arrhythmic drugs (AADs) can provoke AFL with 1:1 atrioventricular conduction (AVC) to cause hemodynamic collapse. We elucidated the characteristics of patients with AFL exhibiting spontaneous 1:1 AVC. Fifteen patients (1:1 AFL group; 11 males, 52.4  ± 13.7 years old) who documented AFL with 1:1 AVC were enrolled and compared to 153 patients without 1:1 AVC (Control group; 137 males, 68.9 ± 11.2 years old). AFL cycle length during maximum AVC was significantly longer in the 1:1 AFL group than in the control group (274.7 ± 37.0 vs. 216.2 ± 25.6 ms,p <  0.001). Among 1:1 AVC group, 9 patients had AADs, and AFL cycle length was significantly longer during 1:1 AVC as compared with 2:1 AVC documented the other day (284.4 ± 41.3 vs. 233.3 ± 26.0 ms,p <  0.001), suggesting enhancement effect of the AADs during 1:1 AVC. Remaining 6 patients who did not take AADs, 2 patients showed enlargement of the tricuspid annulus and 3 patients developed 1:1 AVC during exercise. Multivariate analysis revealed that younger age and the use of AADs was independen t risk factors for the development of 1:1 AFL group. Prolonged AFL cycle length associated with the class Ia/Ic AAD use, slower heart rate during sinus rhythm and younger age were important risk factors for the development of 1:1 AVC during AFL.
Source: Heart and Vessels - Category: Cardiology Source Type: research