Gallik D M, Guidry G W, Mahmarian J J, Verani M S, Spencer W H
Department of Medicine, Baylor College of Medicine, Houston, Texas.
Pacing Clin Electrophysiol. 1994 Feb;17(2):179-85. doi: 10.1111/j.1540-8159.1994.tb01370.x.
The hemodynamic effects of two different pacing modes--rate adaptive atrial (AAIR) versus dual chamber (DDDR) pacing--were assessed in 12 patients with DDDR pacemakers during upright bicycle exercise first-pass radionuclide angiography using a multiwire gamma camera with tantalum-178 as a tracer. All patients had sinus node disease with intact AV conduction. Patients exercised to the same heart rate in random order in these two different pacing modes, AAIR and DDDR with AV delay (of 100 msec) selected to maintain 100% ventricular capture. Cardiac output increased significantly above baseline values during exercise in both pacing modes: 154 +/- 41% (mean +/- SEM, P = 0.002) with AAIR, versus 95 +/- 24% (P = 0.004) with DDDR (P = NS between the two modes). The peak filling rate, likewise, increased in both pacing modes (2.3 +/- 0.21 end-diastolic volumes/sec to 3.8 +/- 0.31 end-diastolic volumes/sec in AAIR [P = 0.0004] and 2.2 +/- 0.18 end-diastolic volumes/sec to 3.4 +/- 0.27 end-diastolic volumes/sec in DDDR [P = 0.0008]). LV ejection fraction was normal at rest (60 +/- 4%, SEM) and did not significantly change with submaximal exercise in either pacing mode (both 56%, P = NS). No significant changes in end-diastolic volume or stroke volume indexes occurred with exercise in either pacing mode. Our study demonstrates that in patients with normal resting LV function, AAIR and DDDR pacing are equally effective in attaining appropriate increases in cardiac output and LV filling during exercise.
采用多丝γ相机，以钽 - 178作为示踪剂，在12例植入DDDR起搏器的患者进行直立自行车运动首次通过放射性核素血管造影时，评估了两种不同起搏模式——频率适应性心房起搏（AAIR）与双腔起搏（DDDR）——的血流动力学效应。所有患者均患有窦房结疾病，但房室传导功能完好。患者在这两种不同的起搏模式下以随机顺序运动至相同心率，AAIR和DDDR的房室延迟（100毫秒）选择为维持100%心室夺获。在两种起搏模式下运动期间，心输出量均显著高于基线值：AAIR模式下为154±41%（平均值±标准误，P = 0.002），DDDR模式下为95±24%（P = 0.004）（两种模式之间P值无显著性差异）。同样，两种起搏模式下的峰值充盈率均增加（AAIR模式下从2.3±0.21个舒张末期容积/秒增至3.8±0.31个舒张末期容积/秒[P = 0.0004]，DDDR模式下从2.2±0.18个舒张末期容积/秒增至3.4±0.27个舒张末期容积/秒[P = 0.0008]）。静息时左室射血分数正常（60±4%，标准误），在两种起搏模式下进行次最大运动时均无显著变化（均为56%，P值无显著性差异）。在两种起搏模式下运动时，舒张末期容积或每搏量指数均无显著变化。我们的研究表明，对于静息左室功能正常的患者，AAIR和DDDR起搏在运动期间使心输出量和左室充盈量适当增加方面同样有效。
