Early experience with dobutamine stress testing and cardiac cine-tomographic imaging in the elderly: antianginal effects of nifedipine-GITS.
OBJECTIVE
To determine the effects of nifedipine-GITS (GITS = gastrointestinal transport system) on angina and cardiovascular responses to stress-dobutamine infusion, we used ultrafast cine-computed tomography (CT) to assess regional wall motion, myocardial perfusion, and indices of ventricular filling and emptying.


METHODS
Randomized, double-blind placebo-controlled efficacy study after an open-label dose titration phase.


METHODS
University of California, San Francisco.


METHODS
Elderly patients (> 60 years; n = 9:8 male, 1 female) with coronary artery disease by history and diagnostic treadmill or coronary angiography.


METHODS
After a 3-week open-label dose-titration phase, eight subjects were randomized to receive either placebo or nifedipine-GITS at the highest tolerated dose for 2 weeks, followed by a crossover to the alternate therapy for 2 weeks. One declined because of singulus in the open-label period.


METHODS
Symptomatic angina relief (frequency and nitroglycerin consumption), dobutamine stress responses (time to ischemia during dobutamine infusions, cardiac output, cardiac ejection fraction, ventricular segmental wall motion, and perfusion as measured by ultrafast cine-CT), and reported adverse effects.


RESULTS
When compared with placebo, nifedipine-GITS administration was associated with less frequent angina and nitroglycerin consumption (NS) and significantly decreased systolic blood pressure. Nifedipine-GITS administration also increased resting supine heart rates. Dobutamine infusions increased heart rate, cardiac output, cardiac ejection fraction, and stroke volume and induced angina symptoms. Neither double product at angina nor systolic indices of cardiac function in response to dobutamine differed between nifedipine-GITS and placebo, although heart rate responses were greater during nifedipine. A trend toward increased peak filling rates was seen during dobutamine stress in the nifedipine-administration period. In most subjects (6/8), perfusion and regional wall motion abnormalities were not visualized on regional wall motion abnormalities were not visualized on either rest or stress cine-CT studies. Edema without congestive heart failure occurred frequently during nifedipine-GITS administration.


CONCLUSIONS
These data suggest that (1) dobutamine stress can be used to induce cardiac ischemia in elderly patients with coronary artery disease, (2) nifedipine-GITS provides symptomatic angina relief in elderly patients, (3) peripheral edema is frequent in elderly patients on nifedipine-GITS, and (4) ultrafast computed cine-tomography testing can be used to assess ventricular performance, but current methodology may not detect perfusion or wall motion abnormalities during angina.
Schwartz
J B
JB
Department of Medicine, University of California, San Francisco.
Caputo
G
G
Abbott
J
J
D000367:Age Factors; D000787:Angina Pectoris / Q000097:blood / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000209:etiology; D002933:Cineradiography; D017023:Coronary Angiography; D003327:Coronary Disease / Q000150:complications* / Q000175:diagnosis; D004280:Dobutamine / Q000008:administration & dosage; D004311:Double-Blind Method; D016503:Drug Delivery Systems; D004487:Edema / Q000139:chemically induced; D005080:Exercise Test; D005260:Female; D005772:Gastrointestinal Transit; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D009543:Nifedipine / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology / Q000627:therapeutic use*; D016491:Peripheral Vascular Diseases / Q000139:chemically induced; D012146:Rest; D014057:Tomography, X-Ray Computed
D004280:Dobutamine; D009543:Nifedipine