Heart Institute, Sheba Medical Center, Tel Hashomer, Israel; * Rambam Hospital, Haifa, Israel. Summary: In a patient with a left atrial myxoma, the tumor adhered ...
Clin. Cardiol. 5 , 136- 138 (1982) 0G. Witzstrock Publishing House, Inc.
Mitral Valve Echocardiographic Pattern Within the Left Atrium M. MOTRO, M . D . , A . S C H N E E W E I S S , M.D., E. GRENADIER,M.D..* H. N. NEUFELD, M.D.
Heart Institute, Sheba Medical Center, Tel Hashomer, Israel; * Rambam Hospital, Haifa, Israel
Summary: In a patient with a left atrial myxoma, the tumor adhered to the anterior leaflet of the mitral valve. This caused movement of the tumor’s stalk in the left atrium in a pattern similar to that of a mitral valve in M-mode echocardiography. An accurate diagnosis was made by cross-sectional echocardiography and confirmed at surgery. Key words: myxoma, echocardiography
Introduction The echocardiographic features of left atrial myxoma are well known (Nasser et al., 1972; Popp and Harrison, 1969; Shattenburg, 1968; Srivastave and Fletcher, 1973; Wolfe and Popp, 1969). A band of echos is present within the left atrium in systole and/or diastole. The movement pattern of the mitral valve is usually distorted with decreased diastolic ejection fraction slope, implying a “mitral stenosis-like” pattern. Mimicking the movement of the mitral valve, to which it was attached, the pedicle of a left atrial myxoma created the impression of a mitral valve in the left atrium.
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M. Motro, M.D. Heart institute Chaim Sheba Medical Center Tel Hashomer, Israel Received: January 23, 1981 Accepted with revision: September 30, 198 I
A 46-year-old female complained of fatigue associated with palpitations on marked exertion since the age of 30 years. Four years prior to her hospitalization, one episode of paroxysmal nocturnal dyspnea was recorded. At the age of 37 and again at 44 years, short transient episodes of confusion and loss of orientation were noted. At that time she was diagnosed as suffering from mitral stenosis. Upon admission the patient appeared to be a welldeveloped 46-year-old female; her pulse was 90/min and regular; blood pressure was 120/80 mmHg; the cardiac examination revealed a slight left parasternal lift; on auscultation an increased S I and Pz and an intermittent S3 were audible; a 2/6 systolic murmur radiating to the axilla was heard at the apex. The rest of the physical examination was within normal limits. The ECG revealed a regular sinus rhythm; P wave was biphasic in VI,with a negative deflection encompassing I mm, suggesting left atrial hypertrophy. The chest x-ray was within normal limits. The M-mode echocardiogram revealed a left ventricle and left atrium of normal size and contractility. There were dense echoes under the anterior leaflet of the mitral valve (Fig. I ) in diastole, and a normal opening of the aortic valve. Echos which seemed to be those of the mitral valve appeared in the center of the left atrium (Fig. 2). Cross-sectional echocardiography clarified that the mitral valve-like structure was in fact the pedicle of a left atrial tumor (Fig. 3). Since this tumor adhered to the anterior leaflet of the mitral valve it therefore imitated a mitral motion. Surgery revealed left atrial myxoma 6 X 3.5 cm in size attached to a stalk connecting to the left inter-atrial septum. Since this tumor adhered to the anterior leaflet of the mitral valve the motion of the valve simultaneouslygenerated a similar motion in the pedicle of the tumor. Histologic examination revealed this adherence to be due to an organizing thrombus with fibrosis.
M. Motro et al.: Echo in myxoma
FIG. I M-Mode echocardiography showing dense echos under the anterior leaflet of the mitral valve.
Discussion The usefulness of echocardiography in diagnosis of left atrial myxoma has been established by previous investigations (Nasser et al., 1972; Popp and Harrison, 1969; Shattenburg, 1968; Srivastave and Fletcher, 1973; Wolfe and Popp, 1969). The M-mode echocardiographic features described in cases of tumor are: ( I ) a mass of echos under the anterior mitral valve leaflet in diastole; (2) a mass of echos within the left atrium in systole and/or in diastole depending on the absence or presence of systolic
FIG. 2 M-Mode echocardiography showing echos resembling those of a mitral valve. in the center of the left atrium.
prolapse of the tumor into the left ventricle; and ( 3 ) decrease in the diastolic slope of the anterior mitral valve leaflet, creating a pattern similar to that seen in mitral stenosis. These features were present in our case. In addition, a band of echos with an M-shaped pattern during diastole was seen within the left atrium. This was similar to the normal mitral valve, which is usually recorded only in the left ventricle. Cross-sectional echocardiographic pattern succeeded in clarifying this unusual M-mode echocardiographic pattern by demonstrating a pedun-
FIG. 3 Cross-sectional echocardiography (and a drawing of i t ) demonstrating a left atrial tumor with a pedicle adherent to the anterior mitral leaflet.
Clin. Cardiol. Vol. 5, February 1982
culated left atrial tumor adherent to the anterior mitral valve leaflet. The movement of the mitral valve generated a similar motion in the pedicle of the tumor. We know of only one reported case with an M-shaped pattern of movement within the left atrium, involving a fibrolipoma of the posterior mitral valve leaflet in a child, and the tumor was recorded in the left atrium only during systole (Barberger et al., 1978). This case differs from the “usual” left atrial myxoma in the following respects: in that the ejection fraction slope of the anterior leaflet of the mitral valve is not decreased and the pedicle creates an unusual pattern. We propose that echocardiographic recording of a mass with mitral valve-like pattern of movement within the left atrium indicates a left atrial tumor adherent to the mitral valve.
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