Beneficial Effects of Biatrial Pacing on Cardiac Function in Patients With Bradycardia - Tachycardia Syndrome

• Published in: Circulation Journal Vol. 69; no. 7; pp. 831 - 836
• Main Authors: Matsumoto, Katsumi, Ishikawa, Toshiyuki, Sumita, Shinichi, Matsushita, Kohei, Kawasaki, Noriko, Kobayashi, Tsukasa, Uchino, Kazuaki, Kimura, Kazuo, Umemura, Satoshi
• Format: Journal Article
• Language: English
• Published: Japan The Japanese Circulation Society 01-07-2005
• Subjects: Aged; Atrial Appendage - diagnostic imaging; Atrial fibrillation; Atrial Function; Biatrial pacing; Blood Flow Velocity; Bradycardia - diagnostic imaging; Bradycardia - therapy; Cardiac function; Cardiac Pacing, Artificial - methods; Female; Humans; Intra-atrial conduction delay; Male; Middle Aged; Myocardial Contraction; Pacemaker, Artificial; Radiography; Sick sinus syndrome; Syndrome; Tachycardia - diagnostic imaging; Tachycardia - therapy; Ultrasonography
• ISSN: 1346-9843; 1347-4820
• DOI: 10.1253/circj.69.831

Background Biatrial (BiA) pacing prevents atrial fibrillation. By an unknown mechanism. The purpose of this study was to use Doppler echocardiography to evaluate the hemodynamic effects during BiA pacing. Methods and Results The subjects were 7 patients with bradycardia - tachycardia syndrome with an implanted pacemaker. Atrial pacing sites were the right atrial appendage (RAA) and coronary sinus. P wave duration during BiA pacing (123 ±16 ms) was significantly shorter than during either RAA pacing (167±19 ms, p<0.05) or sinus rhythm (148±12 ms, p<0.05). Doppler echocardiography revealed a greater cardiac output during BiA pacing than during RAA pacing (4.1±1.1 vs 3.5±0.7 L/min, p=0.042). The Doppler waveform of transmitral flow indicated that the left ventricular contraction interrupted the atrial filling wave during RAA pacing. The interval between the end of the atrial filling wave of transmitral flow and the mitral valvular closing sound was significantly increased by BiA pacing compared with RAA pacing (56±65 vs 40±57 ms, p=0.047). Conclusion Cardiac hemodynamics were improved by BiA pacing and reduction of left atrial load may be one of the mechanisms. (Circ J 2005; 69: 831 - 836)