Hemodynamic consequences of left atrial myxomas as assessed by Doppler ultrasound

Preoperative assessment of mitral valve abnormalities in left atrial myxoma patients using cardiac CT

Background

To retrospectively evaluate mitral valve abnormality in left atrial myxoma patients by using cardiac computed tomography (CT).

Material and methods

Cardiac CT was performed in 56 patients with left atrial myxoma and 50 controls. Tumor and mitral valve characteristics were analyzed. The mitral valve parameters differences were compared between patients with myxoma and controls, myxoma with or without mitral valve obstruction, different obstruction degrees, respectively. Receiver operating characteristic analysis was performed to determine the cut-off values of abnormal mitral valve parameters for myxoma patients. Multiple linear regression, logistic regression models and cox regression analysis were used to determine factors associated with mitral valve abnormalities, mitral obstruction, mitral regurgitation and postoperative recovery, respectively.

Results

Myxoma induced the dilation of mitral valve, with different results among different degrees of obstruction (p<0.001). Mitral valve parameters had relationship with myxoma parameters. The cut-off values for discriminating mitral valve abnormalities in myxoma patients were found. Some significant predictors for mitral obstruction were tumor pedicle-tumor volume and patient age (HR, 0.886-30.811; p = 0.011-0.043). Moreover, the predictor for mitral regurgitation was mitral annulus diameter in diastolic phase (HR, 20.862; 95%CI,1.331-327.100; p = 0.031). Some predictors associated with postoperative recovery of mitral regurgitation were age, mitral annulus area, mitral annulus diameter and mitral valve diameter cutoff value for diastolic phase (HR, 0.001-119.160; p = 0.012-0.028).

Conclusion

Cardiac CT is capable of quantitatively assessing myxoma characteristic and mitral valve abnormality induced by myxoma, thus providing guidance of operative management and postoperative evaluation.

Atrial Myxoma Mimicking Mitral Stenosis

Myxoma is the most common primary cardiac tumor and is usually located in the left atrium. Clinical manifestation relies in large part on the size, location, and architecture of the tumor. There are many reports in the literature of cardiac myxomas causing syncope, embolism, even myocardial infarction. We present a rare case of a patient who underwent urgent surgical resection of a large left atrial myxoma mimicking mitral stenosis. The postoperative course of the patient was uncomplicated. One year after surgery, the patient is asymptomatic and disease-free.

Giant left atrial myxoma mimicking severe mitral valve stenosis and severe pulmonary hypertension

Myxoma is the most common primary tumor of the heart and can arise in any of the cardiac chambers. This paper reports A 50 -year-old woman without medical history and any cardiovascular risk factors was hospitalized for exertional dyspnea and palpitations from three months and signifiant weight loss. Transthoracic echocardiogram showed a giant left atrial myxoma mobile confined to the left atrium in systole, in diastole the tumor was seen prolapsing across the mitral valve into the left ventricle and partially obstructing it and causing severe functional mitral stenosis with a mean gradient of 21,3 mmHg. Severe pulmonary hypertension was confirmed by Doppler PAPs =137 mmHg. The patient was scheduled for cardiac surgery with good outcome.

Left atrial myxoma mimicking mitral stenosis

Cardiac myxoma is a benign (non-malignant) neoplasm that represents the most common primary tumour of the heart. We present the case of a 36 year old woman with background hypertension who presented with features of left ventricular failure and seizures, and was found during transthoracic echocardiography to have left atrial myxoma protruding through the mitral valve orifice. She subsequently had excision of the atrial myxoma. The usefulness of early transthoracic echocardiography in any patient presenting with features of heart failure even when the aetiology seems obvious cannot be over-emphasised.

Giant left atrial myxoma mimicking severe mitral valve stenosis

We report a case of giant left atrial myxoma in a young patient with clinical manifestation as congestive heart failure attributable to severe mitral valve stenosis. An early clinical and echocardiographic diagnosis was performed and the patient had an optimal outcome with surgery treatment.

From the archives of the AFIP: pulmonary vasculature: hypertension and infarction

Pulmonary hypertension is the hemodynamic consequence of vascular changes within the precapillary (arterial) or postcapillary (venous) pulmonary circulation. These changes may be idiopathic, as in primary pulmonary hypertension or pulmonary veno-occlusive disease, but more commonly they represent a secondary response to alterations in pulmonary blood flow. The pulmonary and systemic bronchial circulations form broad anastomoses that largely prevent infarction except in settings of markedly elevated pulmonary venous pressure, underlying malignancy, or excessive embolic burden. Causes of precapillary pulmonary hypertension include long-standing cardiac left-to-right shunt, chronic thromboembolic disease, and widespread pulmonary embolism arising from intravascular malignant cells, parasites, or foreign materials. The classic radiologic features of precapillary pulmonary hypertension are central arterial enlargement, sharply pruned peripheral vascularity, and right-sided heart hypertrophy and chamber dilatation. Postcapillary pulmonary hypertension may develop secondary to focal venous constriction or to compromised pulmonary venous drainage due to left atrial neoplasia, mitral stenosis, or left ventricular failure. Radiologic manifestations of postcapillary pulmonary hypertension include prominent septal lines, small pleural effusions, and occasionally air-space opacities. In addition, radiologic evaluation of postcapillary pulmonary hypertension may demonstrate evidence of pulmonary arterial hypertension, secondary to the retrograde transmission of elevated pulmonary venous pressure across the capillary bed.

Left atrial myxoma presenting as acute respiratory failure

We report the unusual case of a young man with acute respiratory failure caused by a left atrial myxoma. The patient's rapid clinical deterioration and severe hypoxemia suggested the acute respiratory distress syndrome; however, unexpected physical examination findings and a markedly elevated pulmonary capillary wedge pressure implied cardiac abnormality. The use of echocardiography as a bedside tool allowed correct, rapid diagnosis.

Doppler analysis of pulmonary venous flow in left atrial myxoma

In a patient with obstructive left atrial myxoma, we analyzed by pulsed Doppler echocardiography the flow pattern through the mitral valve and in the pulmonary veins. Two mitral flow patterns were observed: the first was present near the medial commissure and along the anterior leaflet and was characterized by the absence of mid-to-late diastolic filling flow; the second was found near the lateral commissure and was characterized by the obstruction of mid-to-late diastolic filling flow, mimicking mitral stenosis. The pulmonary vein flow showed brief and rapidly decelerating anterograde diastolic flow wave and an early systolic retrograde flow wave. These waves were respectively related to the diastolic forward and the systolic backward movement of the tumor. This case report shows that pulmonary vein flow analysis may give new insights into left atrial filling and emptying dynamics in left atrial myxoma.

Detection of valvar obstruction by intracardiac masses using Doppler echocardiography

The purpose of this paper was to examine valvar involvement in patients with intracardiac masses. Seven patients with intracardiac masses were studied by cross-sectional and Doppler echocardiography. In one, a candida vegetation on a mitral Starr-Edwards prosthesis obstructed the aortic valve with a peak transvalvar velocity of 2 m/sec and aortic regurgitation. Another patient with endocarditis demonstrated mitral stenosis as did two patients with left atrial myxomata. Tricuspid stenosis was demonstrated in three patients with right ventricular intracardiac masses (primary and secondary tumour and thrombus). By Doppler, the mitral and tricuspid stenosis was similar to from that seen in rheumatic heart disease with increased peak transvalvar velocity and prolonged pressure half-time. Because of the hazards associated with cardiac catheterisation in intracardiac masses, we conclude that Doppler ultrasound allows for the adequate assessment of the haemodynamic alterations so as to complement the images obtained by cross-sectional echocardiography.