[Mitral valve prolapse and cusp elasticity].

Purpose: To verify if systolic bulging of floppy mitral cusps can to elastic behavior of their myxomatous collagen tissue.

Methods: Five hearts with floppy mitral valves obtained from autopsies were distended with air (20 to 250 mmHg) through a catheter connected to the left ventricle. It was observed if some area of the atrial surface of the coapted cusps showed variable bulging according to the variation of air injection pressures.

[Relationship between volume reduction of the left ventricle and the increase of mitral valve prolapse. An experimental study in dogs].

Purpose: To verify whether accentuated reductions of left ventricular volume lead to mitral valve prolapse.

Methods: Seven mongrel dogs were bled through the internal jugular vein, the systolic systemic pressure being kept between 100 and 140 mmHg by means of continuous infusion of dopamine; the inferior vena cava vein, in tree other dogs, was partially obstructed for 4 to 6 seconds; epicardial echocardiography was carried out in all cases.

Results: Reductions of volemia were about 50% of the estimated total blood volume.

[Necropsy study of the mitral valve according to 5 different echocardiographic planes].

Purpose: To study, in anatomic specimens, the regions of the mitral valve transected by the parasternal long axis, the apical five chamber, the apical four chamber, the apical two chamber and the left ventricle apical long axis echocardiographic views.

Methods: 15 patients' hearts, after fixation through intra-ventricular injection of formalin, were cut according to the five above referred echocardiographic views.

Results: Only the apical five chamber view studied adequately the most anterior regions of both mitral cusps.

[Necropsy study of the mitral valve transected according to five echocardiographic planes].

Purpose: To study, in anatomic specimens, the regions of the mitral valve transected by the parasternal long axis, the apical 5 chamber, the apical 4 chamber, the apical 2 chamber and the left ventricle apical long axis echocardiographic views.

Methods: 15 patients' hearts, after fixation through intra-ventricular injection of formalin, were cut according to the five above referred echocardiographic views.

Results: Only the apical 5 chamber view studied adequately the most anterior regions of both mitral cusps.

[Coronary microcirculation in myocardial reperfusion. The phenomenon of no-reperfusion].

Purpose: The study of the ultrastructural features of the coronary microvessels in postischemic reperfusion.

Material And Methods: Five mongrel dogs of either sex, weighing 2 to 17 kg were studied Each dog was anesthetized with 30 mg. of pentobarbital and ventilated with room air.

A histopathologic study of the mechanism of Evans blue staining of myocardial infarcts in rats.

In a study of the mechanism of Evans blue (EB) staining of experimental infarcts in rats, it has been reported that when the dye was injected iv before left coronary occlusion (LCO) it diffused centripetally from the periphery of the excluded vascular bed region (ExVB), i.e., the myocardial area with circulation interrupted by LCO, to its center.

[The coronary flow reserve during reperfusion in myocardial infarction].

Purpose: The study of coronary flow reserve on the reperfused myocardium damaged by 90 minutes of severe ischemia.

Material And Methods: Nine mongrel dogs of either sex, weighing 12 to 17 kg were studied. Each dog was anesthesiated with 30 mg of pentobarbital and ventilated with room air.

[Communication between left atrium and venous coronary sinus associated with stenosis of the venous ostium and with stenosis the mitral valve. A case report].

Woman, 76 years old with mitral stenosis died due to peripheral arterial embolism. The necropsy identified left atrial to coronary sinus fenestration associated with stenosis of the coronary sinus ostium and rheumatic mitral stenosis.

[Coronary flow reserve during myocardial reperfusion, after 15 minutes of ischemia].

Purpose: To study the coronary resistance reserve on the reperfused myocardium, damaged by 15 minutes of severe ischemia.

Material And Methods: Eight mongrel dogs, of either sex, weighing 14.4 to 21 kg were used.

[Mitral valve prolapse in the 8th and 9th decades of life. Anatomo-pathologic study of 3 cases].

Different anatomo-clinic aspects from three mitral valve prolapse cases are compared to those commonly presented in the literature and are also utilized as a basis for a new classification of this disease. The patients are more than 77 years old, what is in contrast with the current concept of MVP as a disease of young-middle aged women. The first case shows marked ostial dilation and many ruptured chordae: as a consequence, this patient showed severe cardiac dysfunction.

[The mitral valve apparatus: an anatomo-echocardiographic approach].

The shape of the mitral valve ring, the position of its chordae and of its leaflets were studied in 34 normal hearts fixed through intra-ventricular injection of tamponate formalin. As the authors have assumed that the post-rigor left ventricle has an architecture very similar to that seen at to the end of ventricular systole, comparisons were made between the anatomical and the echocardiographic features usually seen at the end of the phase of the cardiac cycle. The mitral ring has the shape of a hyperbolic paraboloid, and this peculiar geometry explains why the "apical-four chambers" view, which explores the most superficial ring segments, is the more appropriate view for detecting mitral valve prolapses.