title: Left ventricular function during asynchronous ventricular pacing: a radionuclide study.
abstract: This study was undertaken to assess ventricular volumes and function by radionuclide angiography during asynchronous ventricular pacing in a group of 22 patients who needed an artificial pacemaker. 14 had ischaemic heart disease and 8 had primary disturbances of conduction of the impulse-forming system. The transition from sinus to a paced rhythm or increasing the pacing rate had little effect on patients with primary conduction disturbances. In contrast, in patients with ischaemic heart disease, the transition to a paced rhythm decreased significantly left ventricular end-diastolic (15.3 +/- 4.7%) and stroke (26.3 +/- 4%) volumes, ejection fraction (9.0 +/- 4.4%), and cardiac output (21.0 +/- 3.9%). Pacing at a progressively increasing heart rate showed that each patient had an optimal rate of pacing.
mesh_terms: D000368:Aged; D001794:Blood Pressure; D002302:Cardiac Output; D002304:Cardiac Pacing, Artificial; D003327:Coronary Disease / Q000503:physiopathology*; D005260:Female; D006321:Heart / Q000503:physiopathology*; D006327:Heart Block / Q000503:physiopathology*; D006339:Heart Rate; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D013318:Stroke Volume