Left ventricular wall motion abnormality and myocardial dysfunction in stress cardiomyopathy: new pathophysiological aspects suggested by echocardiography.

We present our observations on 2 cases of stress cardiomyopathy in which, for the first time, wall motion and myocardial deformation analysis were performed by 2D-strain imaging. Strikingly, in both patients, serial 2D-strain wall motion analysis revealed always synergic and synchronic longitudinal strain and strain-rate patterns, even during the acute stress-induced episodes of left ventricular (LV) dysfunction, indicating uniform myocardial shortening, despite akinetic appearance of the LV apex in both conventional echocardiography and ventriculography. Another important observation was that during the acute stress-induced episodes of severe LV dysfunction the end-systolic LV circumferential wall stress became in both patients several times higher in apical regions than at the LV base. These data suggest that the akinetic appearance of the apex can be related to the high systolic circumferential wall stress in this region, which opposes circumferential fiber shortening and thus apical akinesia and ballooning could be mainly the consequences of LV geometry-induced regional differences in wall stress, rather than a result of severely impaired myocardial contractility in apical regions.