Relationship between function and perfusion early after acute myocardial infarction.

To assess the relationship between baseline left ventricle function, functional reserve and resting myocardial perfusion in patients with acute myocardial infarction (AMI). After AMI the presence of dysfunctioning but viable myocardium plays a determinant role in clinical outcome. Regional ventricular function was evaluated by echocardiography both in resting conditions and during dobutamine infusion (10 microg/kg/min). Perfusion was assessed by magnetic resonance imaging in a single slice approach where the first pass of an intravenously injected bolus of gadolinium-based contrast agent was followed through six regions of interest within the myocardium. In each patient a region with normal function was used as reference and the cross-correlation coefficient (CCC), which described the myocardial perfusion relatively to the reference region (CCC = 1 means equivalent perfusion), was obtained for the other five myocardial regions. Twenty-two patients were enrolled into the study. Sixty-one segments had normal function and normal perfusion (CCC = 0.92+/-0.23). The perfusion deficit was more marked in the 29 regions with resting akinesia-dyskinesia than in the 20 hypokinetic regions (CCC = 0.71+/-0.45 vs. 0.84+/-0.23; p < 0.05). Out of the 29 regions with resting akinesia-dyskinesia the 13 segments which showed functional improvement following dobutamine had a higher resting perfusion than the 16 segments which were unresponsive to dobutamine (CCC = 0.83+/-0.32 vs. 0.61+/-0.52, p < 0.05). Similarly, out of the 20 regions with resting hypokinesia the 11 segments having functional reserve showed an higher resting perfusion than the segments which did not (0.96+/-0.21 vs. 0.69+/-0.19; p < 0.05). Early after AMI, the perfusion deficit reflects the severity of the mechanical dysfunction. In regions with baseline dyssynergy resting perfusion is, in general, higher when contractile reserve can be elicited by stress-echo.

[Mitral valve prolapse: the clinical and echocardiographic characteristics in a hospital outpatient population]. / Il prolasso della valvola mitrale: caratteristiche cliniche ed ecocardiografiche in una popolazione ambulatoriale ospedaliera.

BACKGROUND: Mitral valve prolapse (MVP) is generally regarded as a benign condition, but serious complications (including severe mitral insufficiency, cerebral ischemia, infective endocarditis, complex arrhythmias and sudden death) have been described in a minority of patients and have been correlated to demographic, clinical and echocardiographic characteristics. Both a lack of standardized definition of MVP in earlier studies and the different ways of recruitment of MVP patients may explain the variability in reported complication rates. METHODS: As an offspring of a larger prospective study this paper focuses on the profile of patients who were found to have MVP by M-Mode and two-dimensional echocardiography in several outpatient hospital departments. A total of 8252 consecutive subjects, examined since March 1990 to February 1991 in the Echo laboratories of the Florence area are considered; according to the presence or absence of structural changes (anterior mitral leaflet thickness > 5 mm, leaflet redundancy and/or anulus dilatation) two groups of patients with MVP (A and B) were identified. RESULTS: A MVP was diagnosed in 288 subjects (3.5%), 170 females (59%) and 118 males (41%), mean age 41 +/- 18 years (range 7-84). 110 (38%) were in Group A, 178 (62%) in Group B. The following parameters differed significantly in the two groups: age (45 +/- 17 vs 39 +/- 17 years; p < 0.003); male gender (50% vs 35%; p < 0.01); auscultatory findings (midsystolic click: 31% vs 68%; p < 0.00001; holosystolic murmur: 22% vs 3%; p < 0.00001); left ventricular diameter (53 +/- 7 vs 48 +/- 5 mm; p < 0.00001) and left atrial diameter (38 +/- 8 vs 33 +/- 5 mm; p < 0.00001). Among patients with mitral regurgitation detected by Color Doppler Echocardiography 65% were in Group A (p < 0.00001). CONCLUSIONS: These patients with MVP are obviously selected by the modality of recruitment; hence there is a higher prevalence of subjects with morphologic abnormalities and mitral regurgitation who are older and more likely to be male if compared to individuals with MVP who are found in the general population. A long-term follow-up of these patients is ongoing: owing to the data of the literature about prognostic predictors, a higher incidence of complications with a different prognosis between the two groups (with or without structural changes of the mitral valve) is expected.

[The evaluation of pulmonary artery pressure by suprasternal notch M-mode echocardiography]. / Valutazione della pressione polmonare mediante ecocardiografia M-Mode per via soprasternale.

Four hundred subjects without any sign of cardiac disease were studied by M-Mode echocardiography both by the parasternal approach, in order to record the pulmonary valve and by the suprasternal approach, in order to visualize the aortic arch and right pulmonary artery. Successful recordings were obtained respectively in 70.2% and 92.7% of the attempts. Furthermore we examined with both approaches, 20 patients (pts) with rheumatic mitral valve disease and mean pulmonary artery pressure (mPAP) greater than 20 mmHg (group A), 20 pts with rheumatic mitral valve disease and mPAP less than or equal to 20 mmHg (group (B) and 20 healthy subjects, homogeneous for age and sex (group C). In group A, the pulmonary valve was well recorded by the parasternal approach in 14 pts (70%). Only 9 (45%) showed a diagnostic pattern of pulmonary hypertension. By suprasternal echocardiography we measured the aortic arch/right pulmonary artery end-diastolic ratio: this index, successfully obtained in all pts of group A, B and C, was significantly (p less than 0.001) lower in group A versus group B and C and was significantly correlated (r = 0.84) with mPAP. We, therefore, conclude that the suprasternal M-Mode echocardiographic evaluation of the pulmonary artery is technically easier than the parasternal visualization of the pulmonary valve. Furthermore, it seems to be able to detect more accurately, at least in a selected population, pts with pulmonary hypertension.