The relationship between coronary perfusion pressure and regional myocardial performance of the right ventricular free wall was studied, in the presence or absence of right ventricular hypertension in 13 open-chest dogs. The right coronary artery was perfused through a shunt from a carotid artery. Regional systolic shortening of the right ventricular free wall was measured by means of a sonomic...

OBJECTIVE To determine if left ventricular torsion, as measured by magnetic resonance tissue tagging, is afterload dependent in a canine isolated heart model in which neurohumoral responses are absent, and preload is constant. METHODS In ten isolated, blood perfused, ejecting, canine hearts, three afterloads were studied, while keeping preload constant: low afterload, high afterload (stroke v...

Background Banding of the pulmonary artery to induce left ventricular (LV) hypertrophy followed by arterial switch operation (ASO) within 2 weeks has been performed when a primary ASO was considered high risk because of inadequate LV hypertrophy. Methods and Results Potential adverse myocardial effects of the two-stage procedure were examined by comparing outcome in 18 patients after a rapid tw...

STUDY OBJECTIVE To examine the relation between left atrial (LA) function and exercise performance. DESIGN AND SETTING Retrospective study at a referral cardiopulmonary exercise laboratory in a university hospital. PATIENTS Forty-one patients with recent myocardial infarction. INTERVENTIONS M-mode echocardiography and cardiopulmonary exercise testing combined with radionuclide ventriculog...

An echocardiographic study helps in the assessment of systolic and diastolic left ventricular function due to potential clinical implications over the treatment and the prognosis of different heart diseases. Systolic function depends on three factors: the left ventricular (LV) function, arterial coupling (ventriculoarterial coupling) and blood volume. In the particular case of the left ventricu...

BACKGROUND Conventional cardiac imaging methods do not depict true segmental myocardial shortening, since they cannot determine segment length between fixed points in the myocardium. METHODS AND RESULTS We used electrocardiographically gated magnetic resonance imaging with spatial modulation of magnetization to noninvasively "tag" the myocardium with dark stripes at uniform 7-mm intervals cen...

The role of longitudinally and circumferentially oriented fibres in left ventricular wall motion was examined by digitising echocardiograms of the mitral ring (whose motion reflects long axis change) and of the standard minor axis in 36 healthy individuals, 36 patients with coronary artery disease, 16 with left ventricular hypertrophy, 44 with mitral valve disease (24 of whom had undergone mitr...

Postsystolic shortening and thickening of ischemic and postischemic myocardium are wellrecognized phenomena, but their significance is controversial. To discover whether postsystolic shortening and thickening might represent an active process and to establish their place as possible predictors of functional recovery during and after recovery from ischemia, we examined correlations in severely i...

To evaluate the prognostic significance of clinicopathological measurement in the diagnosis of acute myocardial infarction (MI) in sheep, acute MI was induced by ligation of left anterior descending coronary artery (LAD). For this purpose, twenty four healthy sheep were divided into the sham-operated or control group (group I, thoracotomy without MI) and the experimental group (group II, with M...

Specific information regarding the relation between infarct thickness and regional systolic function is important to the overall understanding of both the pathophysiology of acute and subacute myocardial infarction and the functional benefits of myocardial salvage interventions designed to limit the transmural extent of infarction and thereby preserve left ventricular function. In the present s...