Early systolic closure of the aortic valve

Cardiac amyloidosis mimicking the echocardiographic appearance of obstructive hypertrophic myopathy

A patient with rapidly progressing amyloidosis had cardiac involvement including the unusual echocardiographic appearance of both right and left ventricular outflow tract obstruction, previously unreported in this disease process. Echocardiographic findings were substantiated by autopsy findings of massive biventricular hypertrophy and amyloid deposition in the myocardium.

Temporal relationship between early systolic closure of the aortic valve and aortic flow: experimental study with and without systolic anterior motion of the mitral valve

To investigate the causative factors of typical early systolic closure (ESC) of the aortic valve (AoV), the temporal relationships of ESC with changes in blood pressures and aortic flow (AoF) were examined in dogs with experimentally induced ESC with and without systolic anterior motion (SAM) of the mitral valve. SAM was induced by dobutamine administration. Typical ESC was observed, but no SAM or left ventricular outflow obstruction, in five of the eight dogs treated with isoproterenol. Regardless of the presence or absence of SAM, the onset of ESC occurred before and the end of ESC immediately after the peak of AoF. A similar time relationship was noted between partial closure of the AoV, and pressure and flow changes before administration of isoproterenol, as well as after its termination. These results exclude a rapid decrease in flow velocity as the cause of ESC in our experimental preparation. The nearly uniform temporal relationship between ESC and changes in AoF observed under various conditions is considered to have important implications in the cause of ESC.

Cardiac amyloidosis: combined use of two-dimensional echocardiography and electrocardiography in noninvasive screening before biopsy

Cardiac amyloidosis (CA) presenting with intractable congestive heart failure, electrocardiographic (ECG) normal or low voltage, and conduction or rhythm disturbances, is rapidly fatal. During life, CA often mimics other cardiomyopathies so that definitive diagnosis depends on demonstration of amyloid on myocardial biopsy. On two-dimensional echocardiography (2-D echo), nonspecific features, such as increased ventricular wall thicknesses, predominant diastolic dysfunction, and diffuse myocardial "sparkling," are consistently found in CA. The combined presence of these 2-D echo features and normal or low voltage on ECG is highly suggestive of CA, allows differentiation from other cardiomyopathies, and might be useful in noninvasive screening before myocardial biopsy.

Echographic early systolic partial closure (notching) of the aortic valve in congestive cardiomyopathy

We investigated the prevalence and significance of aortic valve early systolic partial closure (notching) in congestive cardiomyopathy by reviewing clinical and M-mode echocardiographic findings in 33 patients. We also compared their echocardiographic aortic root and valve findings to those in 17 aortic regurgitation patients and 24 normal subjects. Thirteen cardiomyopathy patients (39%) exhibited aortic valve partial closure--similar to the prevalence in the aortic regurgitation (41%) and normal (33%) groups. However, patients with dilated cardiomyopathy and aortic valve notching exhibited a higher mean percentage of partial closure (18% +/- 10) than those with notching in either the aortic regurgitation (8% +/- 9) or normal (5% +/- 2) group. There was no significant difference in age, body surface area, left ventricular dimension, systolic function, or presence of mitral regurgitation between cardiomyopathy patients with and without aortic valve notching, but the former had slightly greater aortic root dimensions and maximal aortic leaflet separation. Although the reason for this difference is unknown, a wider aortic root may result in low-pressure areas bordering the aortic flow stream during early systole, which may favor partial aortic valve closure.

Systolic closure of aortic valve in patients with prosthetic mitral valves

Systolic closure of the aortic valve was found in 10 of 36 patients who underwent mitral valve replacement. Eight patients had early systolic closure, and two had mid-systolic closure. The left ventricular outflow tract dimension on M-mode and two dimensional echocardiograms, left ventricular posterior wall and septal thickness, left ventricular dimensions in systole and diastole, aortic valve opening, and mitral to aortic valve distance were not significantly different between patients with and without systolic closure of the aortic valve. Two of the 10 patients with systolic aortic valve closure were catheterised and in neither was there a gradient between the left ventricle and the aorta. The two patients with mid-systolic closure, however, were the patients who had the narrowest left ventricular outflow tract which could cause significant distortion of blood flow. Systolic closure of the aortic valve in patients with mitral valve replacement is probably not caused by left ventricular outflow tract obstruction, though abnormalities in laminar flow from the left ventricular outflow tract may be involved.