Ishikawa T, Kimura K, Miyazaki N, Tochikubo O, Usui T, Kashiwagi M, Ishii M
Second Department of Internal Medicine, Yokohama City University Urafune Hospital, Japan.
Pacing Clin Electrophysiol. 1992 Nov;15(11 Pt 2):1927-31. doi: 10.1111/j.1540-8159.1992.tb02996.x.
Diastolic mitral regurgitation has been observed in patients with DDD pacemakers when the atrioventricular (AV) delay was prolonged. However, diastolic mitral regurgitation associated with first-degree AV block has not been fully studied. We examined transmitral blood flow in 24 patients with first-degree AV block and normal cardiac function (ages 35.3 +/- 17.4 years), and in nine patients with DDD pacemakers and normal cardiac function (ages 73.1 +/- 8.1 years), using pulsed Doppler echocardiography. Diastolic mitral regurgitation was observed in 19 of 24 patients with first-degree AV block. Although PQ interval was shortened from 0.32 +/- 0.06 to 0.20 +/- 0.05 seconds (P < 0.01) after 1 mg atropine sulfate IV, the interval between P wave (ECG) and the beginning of diastolic mitral regurgitation did not change, while the duration of diastolic mitral regurgitation was shortened from 0.15 +/- 0.03 to 0.05 +/- 0.03 seconds (P < 0.01). There was a significant correlation between changes in PQ interval and changes in the duration of diastolic mitral regurgitation (r = 0.92, P < 0.001). Although cardiac output (3.9 +/- 0.05 L/min) and pulmonary capillary wedge pressure (5.1 +/- 1.5 mmHg) were normal in all patients with pacemakers, diastolic mitral regurgitation was observed when the AV delay was prolonged. The critical PQ interval for the appearance of diastolic mitral regurgitation was 0.23 +/- 0.01 seconds. In patients with prolonged PQ intervals, delayed ventricular contraction following atrial contraction may be associated with mitral regurgitation in the presence of a reversed AV pressure gradient.(ABSTRACT TRUNCATED AT 250 WORDS)
在DDD起搏器患者中，当房室（AV）延迟延长时可观察到舒张期二尖瓣反流。然而，与一度房室传导阻滞相关的舒张期二尖瓣反流尚未得到充分研究。我们使用脉冲多普勒超声心动图检查了24例一度房室传导阻滞且心功能正常的患者（年龄35.3±17.4岁）以及9例DDD起搏器且心功能正常的患者（年龄73.1±8.1岁）的二尖瓣血流情况。在24例一度房室传导阻滞患者中，有19例观察到舒张期二尖瓣反流。静脉注射1毫克硫酸阿托品后，PQ间期从0.32±0.06秒缩短至0.20±0.05秒（P<0.01），但P波（心电图）与舒张期二尖瓣反流开始之间的间期未改变，而舒张期二尖瓣反流的持续时间从0.15±0.03秒缩短至0.05±0.03秒（P<0.01）。PQ间期的变化与舒张期二尖瓣反流持续时间的变化之间存在显著相关性（r = 0.92，P<0.001）。尽管所有起搏器患者的心输出量（3.9±0.05升/分钟）和肺毛细血管楔压（5.1±1.5毫米汞柱）均正常，但当AV延迟延长时仍观察到舒张期二尖瓣反流。舒张期二尖瓣反流出现的临界PQ间期为0.23±0.01秒。在PQ间期延长的患者中，心房收缩后心室收缩延迟可能在存在反向AV压力梯度的情况下与二尖瓣反流有关。（摘要截断于250字）
