The sentinel rash and neurocutaneous presentation of atrial myxoma: Case report and literature review.

INTRODUCTION: Presenting symptoms of atrial myxoma are classically viewed as a triad of cardiac, embolic, and constitutional symptoms. Dermatologic manifestations are viewed as constitutional symptoms and have not received much attention.

METHODS: Illustrative case presentation and literature review.

RESULTS: I admitted a 28 y woman transferred to the comprehensive stroke center with an ischemic stroke treated with intravenous thrombolysis. She had a two year history of skin lesions in the hands/fingers and feet/toes/sole. Skin biopsies showed perivascular neutrophilic inflammatory dermatitis without skin vasculitis. Admission physical exam was notable for chronic skin changes on her hand and foot and an acute erythematous petechial rash over the right side of her face in the distribution of the right external carotid artery. MRI brain showed ischemia involving the right internal carotid artery territory. Transthoracic echocardiogram identified a 2.4 cm atrial myxoma with normal mitral valve function. She underwent uncomplicated cardiac surgery with confirmation of a villous myxoma. At her 8 week follow up visit, she had resolution of her neurologic deficits, and her skin rashes had cleared.Literature review identified 17 additional published cases of sentinel rashes preceding diagnosis of atrial myxoma. Skin changes were often reported in the hand and feet and may involve the digits, palm, and sole. In 8 cases, skin biopsy identified myxomatous emboli in dermal vessels. These cutaneous manifestations share similarities with Osler nodes and Janeway lesions first described in the 1890's, now understood to represent microemboli to the dermis. Seven of these 17 cases (41 %) developed strokes after the initial presentation of cutaneous changes. Our patient had an embolic event primarily affecting the right common carotid artery territory with facial cutaneous changes due to emboli to the external carotid artery territory and cerebral ischemia in the right internal carotid artery territory.

CONCLUSION: I recommend reclassification of the cutaneous signs of atrial myxoma as embolic (to the dermis microvasculature) rather than a constitutional symptom. As the skin biopsy often fails to show myxomatous emboli, physicians should have a high suspicion for a proximal embolic source for patients with a migratory rash preferentially affecting distal extremities. Earlier diagnosis of atrial myxoma when the sentinel rash first appears provides a valuable window of opportunity for cardiac surgery before the patient experiences stroke or peripheral emboli.