[Right ventricular dysfunction in demand-induced ischemia in patients with isolated right coronary artery disease: a...

In ischemic heart disease, the left ventricle has been considered the main target of an imbalance between myocardial oxygen supply and demand. Accordingly, the approach to ischemia has been directed at the evaluation of the left ventricle. The aim of this study was to assess the relative involvement of the left and right ventricle in patients with isolated right coronary artery stenosis. We studied 20 patients with a clinical history of effort angina (15 male, 5 female, mean age 54.1 +/- 6.2) using radionuclide angiography and atrial pacing. Findings were compared with those of 6 normal subjects that were paced at the maximal heart rate of 150 beats/min. Atrial pacing was interrupted because of diagnostic ST segment depression in 8 patients, Wenckebach type atrioventricular block in 1, chest pain without electrocardiographic changes in 4 and the achievement of the maximal prefixed heart rate of 150 beats/minute in 7. With respect to control conditions, during atrial pacing right ventricular ejection fraction declined from 46.8 +/- 6.8% to 37.4 +/- 8.1% (p less than 0.001), while no significant change was observed in left ventricular ejection fraction values (55.2 +/- 4.5% and 51.1 +/- 10.2% respectively). During atrial pacing, left ventricular peak filling rate increased from 1.77 +/- 0.53 to 4.71 +/- 1.8 end-diastolic volumes/second (p less than 0.0001). Qualitative analysis of regional wall motion showed a right ventricular dysfunction in 19/20 patients; this was prevalent in 9 and involving also the left ventricle in 10; an isolated impairment of the left ventricle was observed in 1 patient.(ABSTRACT TRUNCATED AT 250 WORDS)