RIGHT-VENTRICULAR ASYNERGY DURING DOBUTAMINE-ATROPINE ECHOCARDIOGRAPHY

Objectives. We sought to analyze right ventricular contractility durin g dobutamine infusion in patients with right coronary artery disease a nd to elucidate whether the development of right ventricular asynergy aids in characterizing a right coronary artery stenosis. Background. C linical investigations are emphasizing the importance of right ventric ular function in patients with coronary artery disease. Thus, prognosi s of patients with inferior myocardial infarction is influenced by rig ht ventricular function, This study describes the echocardiographic an d electrocardiographic findings during dobutamine-atropine echocardiog raphy in patients with right coronary artery disease. Methods. We stud ied 31 patients with isolated right coronary artery disease and no pre vious myocardial infarction. Six patients with poor acoustic window me re excluded (feasibility 80%). The remaining 25 patients underwent dob utamine-atropine echocardiography. A right coronary artery stenosis lo cated before the origin of the right ventricular branches was consider ed proximal; otherwise, it was considered distal, Results. Right ventr icular asynergy during dobutamine atropine testing developed in 17 pat ients (sensitivity 68%); 14 had proximal and 3 had distal right corona ry artery disease. The following segments were involved: inferior (n = 17), lateral (n = 5) and outflow tract (n = I), No patient showed ant erior asynergy. All 17 patients had left ventricular asynergy as well. Ischemia-free time was 10.7 +/- 6.2 (mean a SD) min for the right ven tricle and 8.9 +/- 5.2 min for the left ventricle (p < 0.05). Ischemic ST changes were recorded in 15 patients (in standard leads in 14 and in right precordial leads in 8). All patients with right precordial ch anges showed ST elevation and had right ventricular asynergy (sensitiv ity and specificity for right ventricular asynergy 47% and 100%, respe ctively). A control group of 25 patients,vith no right coronary artery disease (5 with no disease, 15 with left anterior descending and 5 wi th left circumflex coronary artery disease) underwent dobutamine echoc ardiography. Right ventricular asynergy developed in two patients with left anterior descending artery stenosis (specificity 92%); in both, the anterior wall was affected. Conclusions. Echocardiography during d obutamine infusion is a reliable technique for assessing right ventric ular dysfunction in patients,vith right coronary artery disease. Right ventricular contractility can be assessed during dobutamine echocardi ography in selected patients. (C) 1997 by the American College of Card iology.