Effects of Atrial Pacing on Left Ventricular Performance in Patients with Heart Disease

10 patients with heart disease (8 with left ventricular dysfunction, 2 with mitral stenosis)

Atrial pacing (mean increase in heart rate 44 beats/min)

Resting heart rate (baseline)

Hemodynamic data and systolic time intervals (including cardiac output, minute work, left atrial or pulmonary wedge mean pressure, duration of left ventricular pre-ejection period, aortic diastolic pressure, left ventricular end-diastolic pressure, and dp/dt)surrogate