Atrial myxoma is the most common primary heart tumor.
It usually is nonmalignant and sporadic, but 10% are familial.
Atrial Myxoma; Intracardiac Myxoma.
Cardiac myxomas account for 40 to 50% of primary
cardiac tumors. They are solitary and pedunculated and usually involve only
the left atrium in the nonfamilial form (90% of cases) and both sides of
the heart in the familial form (10% of atrial myxomas). In the sporadic
cases, the female-to-male ratio is 3:1, whereas both sexes are equally
involved in the familial cases. The overall prevalence of primary cardiac
tumors is approximately 0.02% (200 tumors per one million autopsies);
approximately 37.5% of them are myxomas (75 cases of myxoma per one
In cases of familial occurrence (10% of
atrial myxomas), the transmission is autosomal dominant.
The tumor is benign but can be lethal if it
obstructs a valve or causes major embolic events. It arises from the
epithelium and acts as a space-occupying lesion. A left atrial lesion
behaves as a mitral valve stenosis and leads to pulmonary edema, whereas a right
atrial lesion acts as a tricuspid valve stenosis and manifests with dyspnea and
hypoxemia. These tumors are friable, resulting in tumor embolism that occurs
in approximately 30 to 40% of patients. Symptomatology depends on the
location of the tumor (left or right atrium) and the presence of an
Confirmed by an echocardiogram in suspected cases.
Symptoms are produced by mechanical interference
with cardiac function or embolization. It seems that familial disease
involves younger patients with more frequent lesions on the right side of
the heart and more recurrences over the years. Complications associated with
the disease, such as vascular aneurysms, are not more common in the familial
An echocardiogram and ECG are needed
preoperatively to document the extent and number of lesions and their effect
on the hemodynamics of the heart. An angiogram should be part of the workup
to rule out the presence of vascular aneurysms in the cerebral, coronary,
and pulmonary vasculature. If the syndrome form is suspected, rule out
involvement of the adrenals.
Affected patients present with lesions
that can obstruct cardiac valves and thus decrease cardiac output
considerably. Consider avoiding use of medication with the potential to
depress myocardial function (especially contractility), prevent tachycardia,
and maintain adequate preload. In the case of right-sided lesions, use of a
central line in the superior vena cava should be assessed carefully.
No specific implications reported for
In familial cases, atrial myxoma
can be isolated or occasionally is associated with other disorders,
constituting distinct entities.
Carney Complex Type I: Multiple neoplasia syndrome characterized
by spotty skin pigmentation, cardiac and other myxomas organs (e.g., breast,
skin, thyroid gland, neural tissue), endocrine tumors, and psammomatous
melanotic schwannomas. Clinical features include lentigines (brown
discoloration of ...