Effect of increasing heart rate in patients with aortic regurgitation. Effect of incremental atrial pacing on scintigraphic, hemodynamic and thermodilution measurements

Am J Cardiol. 1982 Jun;49(8):1860-7. doi: 10.1016/0002-9149(82)90203-x.


This study was performed to assess the effect of pacing-induced tachycardia in patients with aortic regurgitation. In 12 patients (5 men and 7 women with a mean age of 53 years) with aortic regurgitation, left ventricular end-diastolic and end-systolic volume indexes were measured with multigated equilibrium blood pool imaging, and forward cardiac index was determined with thermodilution, both at rest (mean heart rate +/- standard deviation 72 +/- 8 beats/min) and during atrial pacing at 100 and 120 beats/min. Pacing caused a decremental reduction in left ventricular end-diastolic and end-systolic volume indexes and radionuclide-determined stroke volume index but no change in radionuclide-determined cardiac index or left ventricular ejection fraction. Forward cardiac index increased incrementally from the baseline value at rest to that at 120 beats/min despite a decremental reduction in stroke volume index. There was a stepwise decrease in regurgitant volume/stroke (46 +/- 20 ml/m2 at baseline, 27 +/- 15 at 120 beats/min; p less than 0.05) but no change in regurgitant volume/min (3.38 +/- 1.80 liters/min per m2 at baseline, 3.22 +/- 1.78 at 120 beats/min; difference not significant [NS]) or regurgitant fraction (0.54 +/- 0.13 at baseline, 0.49 +/- 0.13 at 120 beats/min; NS). Mean femoral arterial, pulmonary arterial and pulmonary capillary wedge pressures did not change with pacing.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aortic Valve Insufficiency / diagnosis
  • Aortic Valve Insufficiency / physiopathology*
  • Blood Pressure
  • Cardiac Catheterization
  • Cardiac Output
  • Cardiac Pacing, Artificial*
  • Erythrocytes
  • Female
  • Heart / diagnostic imaging
  • Heart Rate
  • Humans
  • Male
  • Middle Aged
  • Radionuclide Imaging
  • Sodium Pertechnetate Tc 99m
  • Stroke Volume
  • Technetium
  • Thermodilution


  • Technetium
  • Sodium Pertechnetate Tc 99m