Hemodynamic Effects of Different Temporary Pacing Modes for the Management of Bradycardias Complicating Acute Myocardial Infarction

Twelve patients requiring temporary pacing following acute myocardial infarction (AMI) (10 heart block, 2 functional bradycardia) had hemodynamic measurements taken with ventricular demand pacing at 80 ppm (VVI80), ventricular demand pacing at the atrial rate (VVIa), physiological pacing (DDD), and spontaneous (intrinsic) rhythm. VVI80 mode did not improve any hemodynamic parameter compared with spontaneous rhythm. VVIa mode improved diasfolic and mean arterial pressures only. DDD mode improved most hemodynamic parameters compared with spontaneous rhythm (cardiac output by 29% [P < 0.0001]; blood pressure: diastolic by 24% [P < 0.01], systolic by 19% [P < 0.01], mean by 21% (P < 0.005]; pulmonary wedge pressure by 10% [P = 0.057] and right atrial pressure by 24% [P < 0.005]) and also significantly improved some parameters compared with VVIa (cardiac output by 20% [P < 0.001], systolic blood pressure by 11% [P < 0.01] and right atrial pressure by 15% [P < 0.01]). Physiological pacing is hemodynamicaily superior both to ventricular pacing and spontaneous rhythm for patients requiring temporary pacing following AMI. Ventricular pacing at 80 ppm has little hemodynamic advantage over spontaneous rhythm.