Diagnosis of Coronary Stenosis by Two-Dimensional Echographic Study of Dysfunction of Ventricular Segments During and Immediately After Pacing

The adequacy of two-dimensional echocardiography during right atrial pacing for the detection and char acterization of coronary artery stenosis was examined in 10 closed chest dogs. Pacing at successively higher rates up to 210 beats/min was carried out in the control state and again during a 70 % left anterior descending coronary artery stenosisinduced with intracoronary plugs. Left ventricular short-axis echographic cross sections were obtained at several levelsof the left ventricle. After computer-aided standardized subdivision, contractile function of the global section and its subsegments was characterized by computed systolicfractional area change percent and wall thickening percent. Ventricular segments supplied from the site of the 70 % coronary stenosis were delineated in a low papillar