Pseudomitral Intraventricular Valve
A 54-year-old female patient with a brain ischemic attack was admitted to our institution in 2000. A mild systolic murmur was present at the cardiac apex. ECG, chest x-ray, and blood sample analysis (which included calcium levels) were normal. An echocardiogram revealed an echo-dense calcified endocardial ring at the mid-level of the left ventricle with 2 small pseudovalves that conducted the flow to the apex during diastole and to the basal portion of the left ventricle during systole (Figure 1). Pulsed Doppler sampling over the pseudomitral valve showed a pattern that mimicked the mitral valve pattern in diastole and the left ventricular outflow tract pattern in systole (Figure 2). All basal and apical myocardial segments contracted normally, and the left ventricular ejection fraction was 62%. Mild mitral and tricuspid regurgitation were observed. Cardiovascular magnetic resonance images showed the same findings (Figure 3A and 3B). The pseudomitral valve measured 2.3 cm2 by cardiovascular magnetic resonance and 2.4 cm2 by the Doppler half-pressure method. A computed axial tomography confirmed the calcified nature of the midventricular structure (Figure 3C). There was no evidence by any method for intracavitary thrombus formation. However, we presumed that the anfractuous aspect of the mid-ventricular structure and pseudomitral valve may constitute a site for settlement of thrombus. For this reason the patient started anticoagulant therapy in 2000 and suffered no ischemic episodes during a 7-year follow-up period. We believe that this case constitutes a new morphological disorder, likely of congenital origin.
The online-only Data Supplement, consisting of figures and movies, can be found at http://circ.ahajournals.org/cgi/content/full/116/8/e306/DC1.