title: Scintigraphic evaluation of myocardial and cerebral blood flow in patients with a history of coronary artery bypass grafting.
abstract: This paper deals with a comparative scintigraphic evaluation of the changes that occur in coronary and cerebral circulation in patients with coronary artery disease (CAD) after coronary artery bypass grafting (CABG) under conditions of cardiopulmonary bypass (CPB) or beating heart. Twenty-nine CAD patients who underwent CPB were examined. Of these, 14 patients were operated on using CPB (the first group) and 15 patients on the beating heart using the myocardial "stabilizer" Octopus (the 2nd group). The patient groups matched in terms of the age, sex, the clinical and angiographic factors. Perfusion scintigraphy of the heart and brain by means of single-photon emission computed tomography (SPECT) and the neurologic evaluation were performed twice in all the patients: before and 2-4 weeks after CABG. The second group patients demonstrated a significant lowering of the mean magnitude of stable defects (SD) of myocardial perfusion. The lowering or disappearance of SD was observed in a greater percentage of cases versus the first group. All the patients were found to have areas of hypokinesis in the SD projection. Also, the second group showed a significant rise of the mean magnitude of left ventricle ejection fraction. Operations with CPB were associated with a 5% decrease of cerebral blood flow in the frontal and temporal lobes of the right hemisphere. No significant deterioration of brain perfusion was observed in patients (on the whole in the group) operated on without heart arrest. It is noteworthy that there was a significant improvement of the average group indicators of cerebral perfusion in the right occipital and posterior segments of the temporal lobes. The changes in cerebral perfusion were in agreement with the course of changes in the cognitive status. Thus, CABG on the resting heart in CAD patients favours a more remarkable restoration of perfusion and contractility of the hibernated myocardium versus revascularization performed under CPB and exerts, as a result, a beneficial effect on cerebral circulation and the neuropsychological status of the patients.
authors.affiliation: Laboratory for Radionuclide Research Methods, Research Institute of Cardiology, Tomsk Scientific Center, Siberian Branch, Russian Academy of Medical Sciences, Tomsk, Russia. nuclear@cardio.tsu.ru
authors.forename: Zh V
authors.initials: ZhV
authors.lastname: Vesnina
authors.forename: I Iu
authors.initials: IIu
authors.lastname: Efimova
authors.forename: B N
authors.initials: BN
authors.lastname: Kozlov
authors.forename: N Iu
authors.initials: NIu
authors.lastname: Efimova
authors.forename: Iu B
authors.initials: IuB
authors.lastname: Lishmanov
mesh_terms: D000328:Adult; D001921:Brain / Q000098:blood supply / Q000378:metabolism / Q000503:physiopathology; D002545:Brain Ischemia / Q000150:complications / Q000175:diagnosis* / Q000601:surgery*; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology; D001026:Coronary Artery Bypass / Q000379:methods*; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis* / Q000601:surgery*; D009206:Myocardium / Q000378:metabolism; D009483:Neuropsychological Tests; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed / Q000295:instrumentation*