When Catastrophe Strikes — A Case of Atrial Myxoma with Distal Embolization

ABSTRACT: Primary tumors of the heart are rare, with an incidence between 0.0017 and 0.19 percent in unselected patients at autopsy.1 About three-quarters of these tumors are benign, and nearly half of these benign tumors are myxomas. First described in 1845, myxomas were diagnosed posthumously until the 1950s. The clinical features are determined by their size, locations and mobility. Embolism occurs in one-third of patients, but it is rare for patients to initially present with multiple, simultaneous widespread emboli.1–3 J INVASIVE CARDIOL 2008;20:E314–E315 Case Presentation. A 56-year-old male with a past medical history of diet-controlled hypertension presented to the emergency department via emergency medical services (EMS) after he collapsed at a local restaurant while playing pool. He had recently undergone a complete physical examination at his primary care physician’s office, which was unremarkable. He was not on any medications, and his surgical and family history was unremarkable. His social history was significant for 15 years of smoking a pack a day and social drinking, but he did not use any recreational drugs. At the restaurant, EMS personnel noted the patient to be conscious and diaphoretic, with incomprehensible speech. He was unable to move his right side and was intubated for airway protection. His left arm blood pressure was 176/88 mmHg, with a regular pulse rate of 92/minute, a respiratory rate of 24/minute and oxygen saturation of 99 percent on room air. A chest examination was unremarkable and cardiac auscultation revealed regular tachycardia. In the emergency room, he was noticed to have severe blanching of both his lower extremities as well as his right arm, with no palpable pulses. A head computed tomography (CT) (without contrast) scan was negative for any acute changes. Electrocardiography (ECG) revealed marked ST elevation in the inferior leads (Figure1), and a portable chest X-ray raised the concern of possible mediastinal widening. At this time, a differential diagnosis of acute aortic dissection was entertained and the patient underwent an emergent trans-esophageal echocardiogram (TEE). It revealed a 2.5 cm x 4.5 cm friable mass in the left atrium, with a broad base anchored on the intra-atrial septum “waving in the breeze”, suggestive of atrial myxoma (Figure 2). Coronary angiography showed no significant coronary occlusion. Aortogram done during cardiac catheterization showed a complete occlusion of distal aorta from thrombus embolization (Figures 3 and 4). The patient underwent emergent bilateral ileo-popliteal and femoral embolectomies as well as thrombolytic therapy for his right arm. Biopsy of the atrial mass showed spindle-shaped cells within a myxoid matrix, confirming its myxomatous origin. The patient’s condition stabilized and he subsequently underwent successful surgery for removal of the myxoma remnants. He had a prolonged course in the intensive care unit with postsurgical complications, but was eventually discharged to an inpatient rehabilitation facility. After 1 year, he continues to undergo physical therapy for his significant residual neurological weakness. Discussion. Myxomas are tumors of endocardial origin that usually project from the endocardium into the cardiac chambers. With an incidence of 75 per million autopsies, atrial myxomas present a diagnostic challenge for their varied and often silent presentation on physical examination. Relatively more common in women, the age of presentation varies from child-birth to nonagenarians, but is more common in the 30- to 60-year-old age group. Most patients present with one or more of the triad with embolism, intracardiac obstruction and constitutional symptoms caused by cytokine production. Embolism occurs in 30–40% cases and may result from the release of tumor fragments or thrombi on the tumor. Auscultatory findings are variable and can depend on body position in mobile tumors. The characteristic “tumor-plop”— a diastolic filling sound — is heard in less one-third of patients.1–4 ECG findings may represent the hemodynamic alterations resulting from the tumor. ST elevations are believed to be a result of tumor embolization. In our patient, the ST elevations resolved during coronary angiography, likely due to the embolus moving distally to a smaller branch vessel, thereby explaining the lack of obvious coronary occlusion. Noninvasive tests like two-dimensional surface echocardiography and CT/magnetic resonance imaging have high diagnostic superiority, especially with large tumor sizes. TEE is particularly helpful in small tumors and helps define the site of insertion, as well as the morphological features. The pathologic predictors of embolism are believed to be absence of calcium, absence of thrombus and polypoid shape.4,5 Surgical resection is the treatment of choice and is usually curative. Conclusion. Atrial myxomas are rare and benign cardiac tumors with potentially catastrophic consequences. A high index of suspicion is encouraged in patients presenting with a differential diagnosis of peripheral embolization. Any warning signs on a detailed history and physical examination should warrant timely diagnostic evaluation. Curative options are available and should not be delayed, as patients may develop potentially lethal complications.

1. Reynen K. Cardiac myxomas. N Eng J Med 1995;333:1610–1617.
2. Colucci WS, Schoen FJ, Braunwald E. Primary tumors of the heart. In: Heart Disease: A Textbook of Cardiovascular Medicine. 5th Ed. 1997, pp. 1464–1477.
3. Pinede L, Duhaut P, Loire R. Clinical presentation of left atrial cardiac myxoma. A series of 112 consecutive cases. Medicine 2001;80:159–172.
4. Scott N, Veinot JP, Chan KL. Symptoms in cardiac myxoma. Chest 2003;124:2408.
5. Grebenc ML, Rosado-de-Christenson ML, Green CE, et al. Cardiac myxoma: Imaging features in 83 patients. Radiographics 2002;22:673–689.