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

Journal Article · Tue Jun 01 00:00:00 EDT 1982 · Am. J. Cardiol.; (United States)

DOI:https://doi.org/10.1016/0002-9149(82)90203-X· OSTI ID:7055933

Firth, B G; Dehmer, G J; Nicod, P; Willerson, J T; Hillis, L D

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.

• Research Organization: Department of Internal Medicine (Cardiology), the University of Texas Health Science Center, Dallas
• OSTI ID: 7055933
• Journal Information: Am. J. Cardiol.; (United States), Journal Name: Am. J. Cardiol.; (United States) Vol. 49:8; ISSN AJCDA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
AORTA
ARTERIES
BLOOD CIRCULATION
BLOOD VESSELS
BODY
CARDIAC PACEMAKERS
CARDIOVASCULAR SYSTEM
COUNTING TECHNIQUES
DIAGNOSIS
DIAGNOSTIC TECHNIQUES
DRUGS
HEART
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
ORGANS
PATHOLOGY
PATIENTS
RADIOISOTOPE SCANNING
RADIOPHARMACEUTICALS
SCINTISCANNING