단일유도 VDD 심박동조율기 환자에서 방실 동시화에 대한 고찰

Abstract

For the past 10 years, VDD pacemakers have been substituted for DDD pacemakers, due to their ease of implantation and follow up. The degree of AV synchrony and associated factors were evaluated in the patients with VDDR pacemakers. Subjects and Methods：Twenty one patients, 10 males and 11 females, were enrolled. The mean age of the patient was 56 years. In the supine position, the atrial sensing threshold and cardiac cycle data were checked to evaluate the AV synchrony with a programmer. If the AV synchrony was less than 90%, it was considered improper synchronization. Results：The measured P wave amplitudes were 2.33 and 1.22mV at implant and follow up, respectively. From the follow up cardiac cycle data, the percentage of ventricular pacing only (Vp), atrial sensing and ventricular pacing (AsVp) and the total percentage of AV synchronization (PAS) were 21.38, 76.33 and 77.77%, respectively. Inadequate AV synchrony was observed in 11 patients. The causes were the absence of a minimal tracking limit, a faster pacing rate than the patient’s resting rate, atrial fibrillation, sinus node dysfunction, atrial under sensing and functioning of the rate adaptive function in 4, 3 and 1 each, respectively. After rectifying the causes, the cardiac cycle data improved from 32.83 to 5.17% for the Vp, from 62.67 to 91.5% for the AsVp and from 65.52 to 94.38% in the PAS, all with statistical significance. Conclusion：For proper AV synchrony, it is necessary to carefully manipulate, not only the P wave sensitivity, but also several other of the pacemaker parameters. (Korean Circulation J 2003;33 (8):709-714) KEY WORDS：Pacemaker, artificial；Atrioventricular block；Synchronization.

방실 동시성(atrioventricular synchrony)을 유지하 는 조율은 심실 박동 조율(ventricular pacing)보다 혈 역학적 이득, 심방 세동 발생의 감소, 삶의 질 향상등 다 양한 면에서 우위를 차지하고 있다.1-4) 동결절(sinus node) 기능이 정상이고 완전 방실 차단을 갖는 환자에 서의 이상적인 심박동조율은 심방의 신호를 감지하고 심실에서의 조율이라 할 수 있다. 고식적인 DDD 심박동 조율기보다 VDD 심박동조율기가 싸고 시술이 간편한 이점이 있고5)6) 또 VDD 심박동조율기의 신빙성이 입 증되면서7)8) 지난 10년간 DDD 심박동조율기가 VDD 심박동조율기로 많이 대체되고 있다. 본 연구는 VDD(R) 심박동조율기를 삽입한 환자에서 방실 동시성 유지의 정도와 이에 관여하는 인자들을 알아 보고자 하였다