ALTERATIONS IN LEFT-VENTRICULAR SHAPE IN PATIENTS WITH ANGINA AND SINGLE-VESSEL CORONARY-DISEASE

Background: Left ventricular shape alterations, apparently independent of acute ischaemia or previous myocardial infarction, have been descr ibed in patients with stable angina. Our previous observations had bee n made in a group of patients with multivessel coronary disease; it wa s therefore not possible to establish a clear-cut anatomical relations hip between the location of ischaemia and the changes in left ventricu lar contour. The aim of this work was to extend the previous observati ons by analysing left ventricular shape in patients with angina and si ngle-vessel coronary disease, in whom the potentially ischaemic region can be easily localized. Methods: Fifty-eight patients with stable or unstable angina were retrospectively selected if they had single-vess el disease, normal regional and global function and no previous myocar dial infarction: 37 had a critical stenosis (more than 75% diameter re duction) of the left anterior descending artery and 21 had a critical stenosis of the right coronary artery. Patients with left ventricular hypertrophy or any other obvious cause of myocardial dysfunction were excluded. All patients underwent haemodynamic study. Left ventricular global shape was evaluated by calculating eccentricity and circular in dices; regional curvature was measured at 90 points along the angiogra phic contours (right anterior oblique projection) by applying a window ed Fourier analysis. Results were compared with those obtained in 16 n ormal subjects. Results: Patients had significant diastolic alteration s in left Ventricular shape, which assumed a more rounded aspect than normal. Regional curvature was significantly altered at several points pertaining to the anterior, apical and inferior segments. The pattern of changes in regional curvature was about the same in the left anter ior descending and right coronary artery groups, with the involvement of regions supplied by angiographically normal arteries, although the extent of alteration was greater in patients with stable, chronic angi na (more than 6 months) and in patients with stenosis of the left ante rior descending artery. Conclusions: Patients with angina, no previous myocardial infarction and normal systolic function had left ventricul ar shape abnormalities either in the potentially ischaemic or in the r emote zones. The mechanism leading to these changes is still speculati ve.