To the Editor:
Conte and Katz1 recently provided images of a mitral valve papillary fibroelastoma detected by transesophageal echocardiogram. The patient presented with an embolic stroke, and the tumor was removed surgically. The authors postulated that a tumor fragment was responsible for the embolic event. This deserves comment because there is another possibility, potentially important for patient management.
Papillary fibroelastomas are benign cardiac tumors, usually located on valves, thought to be related to Lambl’s excrescences. They may be incidental findings at surgery or autopsy, or clinically they have been associated with neurological events, stroke, angina, myocardial infarction, or sudden death.2 3 These events are thought to be related to emboli or to tumor obstruction of a coronary artery ostium.
Unlike myxoma, another common benign cardiac tumor that may be valvular and associated with similar clinical events, fragments of the tumor have only rarely been found in the arteries involved.2 3 4 It is more likely that the embolic material is fibrin or thrombus originating from the tumor surface. This probably relates to local trauma and endothelial damage at the tumor surface.3 4 5
These tumors are composed of papillary fronds of collagen and elastin covered by endothelial cells. They are firmly attached to the valve. By pathological examination, it may be necessary to examine multiple slides of the tumor, but not uncommonly, small fragments of adherent fibrin and thrombus are found.
This is of clinical importance because some authors have proposed that as an alternative to surgical excision with valve repair or replacement, the tumors should be treated by anticoagulation.3 4 5 This may be a viable treatment option while the patient is on the waiting list awaiting surgery or in patients in whom surgery is contraindicated.
- Copyright © 1999 by American Heart Association
We thank Dr Veinot for his excellent comments concerning embolization and fibroelastomas. The association between fibroelastomas and embolic stroke is indeed controversial. The diagnosis of ischemic stroke from left-sided papillary fibroelastomas is usually made by exclusion. In a recent study, Yee and colleaguesR1 reported on 15 patients with papillary fibroelastomas and found 5 patients (33%) who had ischemic strokes with no other etiologic explanation. Furthermore, thrombus is occasionally superimposed on papillary fibroelastomas.R2 It may have been responsible for the stroke in the patient whom we reported, although no fibrin or thrombus was observed on pathology. Anticoagulation is a viable alternative to surgical excision of the tumor, particularly when there are contraindications to surgery. In 1 case report, no recurrence of transient ischemic attack occurred in 3 years after excision of a left-sided papillary fibroelastoma. Follow-up data on patients who underwent surgical excision are rare, and we are unaware of any follow-up studies on patients treated with anticoagulation alone. The best method of management of papillary fibroelastomas, the second-most-common cardiac tumor,R3 awaits further observations and clinical trials.