Effect of coronary artery bypass grafting on left ventricular systolic function at rest: evidence for preoperative subclinical myocardial ischemia

Journal Article · Wed Jun 01 04:00:00 EDT 1988 · Am. J. Cardiol.; (United States)

DOI:https://doi.org/10.1016/0002-9149(88)91164-2· OSTI ID:6908645

Dilsizian, V; Bonow, R O; Cannon, R.O. 3d.; Tracy, C M; Vitale, D F; McIntosh, C L; Clark, R E; Bacharach, S L; Green, M V

Successful coronary artery bypass grafting (CABG) improves exercise-induced left ventricular (LV) dysfunction in patients with coronary artery disease (CAD), but its potential for improving resting LV function remains controversial. To assess the influence of CABG on LV function at rest, 31 CAD patients without previous myocardial infarction were studied before and 6 months after CABG by radionuclide angiography after all cardiac medicines were withdrawn. No patient had angina or ischemic electrocardiographic changes at rest. In 27 patients with patent bypass grafts, CABG significantly increased LV ejection fraction during exercise (47 +/- 11% before to 63 +/- 9% after operation, p less than 0.001), indicating reduction in exercise-induced LV ischemia. Moreover, LV ejection fraction at rest also increased (55 +/- 9 to 60 +/- 8%, p less than 0.001), with 20 of 27 patients manifesting an increase compared with preoperative values. Eleven of these 20 patients had apparently normal LV function at rest (ejection fraction and regional wall motion) before CABG. LV regional ejection fraction was computed by dividing the LV region of interest into 20 sectors. Regional analysis indicated that improved ejection fraction at rest after CABG occurred in regions developing ischemia during exercise before CABG. In 4 patients with occluded grafts, the ejection fraction at rest was unchanged by CABG globally (59 +/- 8 to 58 +/- 9%, difference not significant) and regionally. Thus, LV global and regional function at rest improved after successful CABG, even in patients with normal global LV ejection fraction and no visually detectable wall motion abnormality before surgery.

• Research Organization: Cardiology Branch, National Heart, Lung, and Blood Institute, Bethesda, MD (USA)
• OSTI ID: 6908645
• Journal Information: Am. J. Cardiol.; (United States), Journal Name: Am. J. Cardiol.; (United States) Vol. 61:15; ISSN AJCDA
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ARTERIES
BLOOD VESSELS
BODY
CARDIOVASCULAR DISEASES
CARDIOVASCULAR SYSTEM
CORONARIES
COUNTING TECHNIQUES
DIAGNOSIS
DISEASES
EXERCISE
GRAFTS
HEART
ISCHEMIA
ISOTOPES
MUSCLES
MYOCARDIUM
ORGANS
PATIENTS
RADIOISOTOPE SCANNING
TECHNETIUM ISOTOPES
TRANSPLANTS
VASCULAR DISEASES