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Ann Thorac Surg 2005;80:1712-1718
© 2005 The Society of Thoracic Surgeons

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Original article: Cardiovascular

Surgical Treatment of Cardiac Papillary Fibroelastoma: A Single Center Experience With Eighty-Eight Patients

^a Division of Cardiovascular Surgery, Mayo Medical Center, Rochester, Minnesota
^b Division of Anatomic Pathology, Mayo Medical Center, Rochester, Minnesota

Accepted for publication April 22, 2005.

^_* Address correspondence to Dr Mullany, Division of Cardiovascular Surgery, St. Mary's Hospital, Rochester, MN 55902 (Email: cmullany{at}mayo.edu).

Presented at the Poster Session of the Forty-first Annual Meeting of The Society of Thoracic Surgeons, Tampa, FL, Jan 24–26, 2005.

	Abstract

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BACKGROUND: Cardiac papillary fibroelastoma is a rare benign tumor that can cause thromboembolism. We have found no large surgical series describing its treatment and outcome.

METHODS: A retrospective review of all patients treated surgically for this tumor from 1985 to 2002.

RESULTS: There were 88 patients with a mean age of 62 ± 16 years. Sixty-two (71%) were male. Cardiac papillary fibroelastoma was a primary indication for surgery in 47 (group 1, 53%) and an incidental finding in 41 (group 2, 47%). The common clinical symptoms were neurologic (group 1) and cardiac (group 2). Cardiac valves were predominantly involved (77%); the aortic valve was the most affected (52%). Other common sites were the left ventricular outflow tract (18%) and anterior mitral leaflet (11%). All heart valves were involved in one patient. Seventy-three patients (83%) had shave excision and 8 (9%) excision with valve repair. Of 5 (6%) valve replacements, 2 were for concurrent degenerative valve disease. Concomitant procedures included repair or replacement of another valve (32 %), CABG (28%), and septal myectomy (19%). Surgical mortality occurred in 1 patient (2.1%) in group 1 who had concomitant lung resection for bronchiolitis obliterans. There was no tumor recurrence, and no tumor-related late morbidity or mortality at a mean follow-up of 3 years.

CONCLUSIONS: Cardiac papillary fibroelastoma has a propensity to affect the anatomically contiguous structures of the aortic valve, left ventricular outflow tract, and anterior mitral leaflet. Surgical treatment by simple shave excision is low risk and can achieve good results.

	Introduction

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Cardiac papillary fibroelastoma is a rare benign tumor that most commonly involves heart valves and may cause thromboembolism or mechanical interference with valvular function. The incidence of cardiac tumors in autopsy series is estimated at 0.021%, and of these, cardiac papillary fibroelastoma constitutes 10% [1]. This may not represent the true prevalence of the tumor because, in the past, it was seldom clinically suspected as a cause of morbidity and mortality and was usually diagnosed incidentally at autopsy [2]. The increasing application of echocardiography and the recognition of its echocardiographic features [3, 4] have led to the more frequent clinical diagnosis of cardiac papillary fibroelastoma.

There are several case studies and pooled case reports describing the clinical, pathologic, and echocardiographic characteristics of the tumor [5–7], but we have found no large series describing its surgical treatment and clinical outcome. This retrospective cohort study examines the clinical presentation, surgical management, and clinical outcome of cardiac papillary fibroelastoma.

	Patients and Methods

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All patients who underwent surgical treatment for cardiac papillary fibroelastoma at our institution between 1985 and 2002 were identified from the cardiovascular surgery and pathology databases. Institutional Review Board approval was obtained for this study on August 31, 2004. Clinical histories, echocardiographic reports, operative notes, and histopathologic findings were reviewed. Demographic characteristics such as age and gender, and clinical data including presenting symptoms, concurrent cardiac disease, comorbidities, tumor location, left ventricular ejection fraction, operative procedures, and follow-up findings were collated. The clinical diagnosis of cardiac papillary fibroelastoma was made by echocardiography and confirmed by histopathologic examination in all patients. The echocardiographic and histopathologic appearances of this lesion are shown in Figures 1–7, and have been described previously from our institution [4].

View larger version (61K): [in this window] [in a new window]   Fig 1. Cardiac papillary fibroelastoma (arrow) on the aortic valve, in the long-axis view of a transthoracic echocardiogram (63-year-old male). (LA = left atrium; Ao = aortic root.)

View larger version (117K): [in this window] [in a new window]   Fig 2. Intraoperative transesophageal echocardiogram (short-axis view), demonstrating aortic valve papillary fibroelastomas (53-year-old male). (R = right aortic cusp; L = left aortic cusp; N = noncoronary [posterior] cusp.)

View larger version (47K): [in this window] [in a new window]   Fig 3. Papillary fibroelastoma (arrow) on the ventricular septum near the left ventricular outflow tract, in a long-axis view of a transthoracic echocardiogram. (LA = left atrium; LV = left ventricle.)

View larger version (115K): [in this window] [in a new window]   Fig 4. Cardiac papillary fibroelastoma (arrow) on the mitral valve, in a two-chamber view of a transthoracic echocardiogram. (LA = left atrium; LV = left ventricle.)

View larger version (64K): [in this window] [in a new window]   Fig 5. Papillary fibroelastoma of the pulmonary valve photographed under water, showing multiple slender fronds and giving the appearance of a sea anemone.

View larger version (67K): [in this window] [in a new window]   Fig 6. Multiple papillary fibroelastomas involving a rheumatic mitral valve.

View larger version (122K): [in this window] [in a new window]   Fig 7. Microscopic appearance of a cardiac fibroelastoma of the mitral valve, showing multiple fronds (hematoxylin and eosin, low power).

Surgical Techniques
Complete surgical excision was achieved in all patients using standard techniques of cardiopulmonary bypass and intraoperative transesophageal echocardiography. Valvular cardiac papillary fibroelastomas were approached by conventional routes for valvular surgery, and direct atriotomy for atrial tumors. Tumors were removed in the left ventricle by the transaortic route and in the right ventricle through the tricuspid valve. The method of resection was usually shave excision and this was valve-sparing in most cases. Defects resulting from extensive excision of valvular lesions or subvalvular apparatus were corrected by valve repair or replacement.

Statistical Analysis
Statistical analysis was performed using the JMP statistical discovery software (SAS Institute, Inc, Cary, NC; 1989–2004). Categorical data are expressed as percentages and continuous data as mean ± standard variation. Comparison between means was done with the Student t test, the Mann-Whitney test, and the analysis of variance test to determine significance. Statistical significance was defined as p less than 0.05 (two-tailed).

	Results

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Patient Characteristics
There were 88 patients with a mean age of 62 ± 16 (range, 23 to 86) years. Sixty-two (71%) were male. Cardiac papillary fibroelastoma was a primary indication for surgery in 47 patients (group 1, 53%) and was an incidental echocardiographic or surgical and/or histologic finding in 41 patients undergoing cardiac surgery primarily for other conditions (group 2, 47%). The most common clinical symptom in group 1 patients was neurologic (53%); cerebral embolism in 38%, retinal embolism in 9%, and transient ischemic attacks in 6%. Other presentations for this group were due mainly to concurrent cardiac disease and included dyspnea 25%, syncope 17%, and angina 13%.

Group 2 patients usually presented with cardiac symptoms: dyspnea (83%), angina (22%), and syncope (17%). Congestive heart failure was present in 39% and thromboembolism occurred in 15%. Table 1 shows the clinical profile of each study group. Among all 88 patients, 55 (63%) had coexistent cardiac disease and 13 (15%) had undergone previous cardiac surgery.

Cardiac papillary fibroelastoma grew on all valve surfaces. Of the 60 patients with left heart valvular tumors, data on the location of the tumor on the valves were documented in 41 patients (68%). The left ventricular-facing, coapting, and aortic-facing surfaces of the aortic valve were affected in 19, 6, and 7 patients, respectively; correspondingly, the atrial-facing, coapting, and ventricular-facing surfaces of the mitral valve were involved in 2, 1, and 6 patients. There was no correlation between the location of left heart tumors for the three common sites, tumor volumes, and the valvular surfaces affected with systemic thromboembolism. Twenty of 46 patients with aortic valve lesions (43%) and six out of 14 with mitral lesions (43%) had systemic thromboembolism. One patient with a tumor on the atrial-facing surface of the anterior leaflet of the tricuspid valve and a patent foramen ovale presented with cerebral embolism.

Surgical Resection
Complete tumor excision was accomplished by simple shave excision in most patients (83%) (Fig 8). This was always adequate for nonvalvular lesions and for most valvular lesions, in which case it was valve-sparing. Comparatively, more aortic than mitral valve tumors (89% vs 64%) were treated by simple shave incision. Valve repair of tumor site in 8 (9%), and valve replacement in 5 (6%) was necessary to correct valvular defects resulting from extensive excisions, sometimes involving the subvalvular apparatus. Of the five valve replacements, two were for involvement of the papillary muscles of the mitral valve, and one for tumor on the 3 cusps of a regurgitant pulmonary valve (see Fig 5) in a patient who previously had pulmonary valvotomy for congenital stenosis. The other 2 patients had concurrent degenerative valve aortic valve disease for which valve replacement was indicated. Concomitant procedures included coronary artery bypass grafting (CABG) in 25 (28%), repair or replacement of another valve in 28 (32 %), and septal myectomy in 17 patients (19%).

View larger version (28K): [in this window] [in a new window]   Fig 8. Pie chart displaying the distribution of operative procedures for the treatment of cardiac papillary fibroelastoma in all 88 patients.

The follow-up period ranged from 0 to 8.3 years during which time repeat echocardiography was performed in 54 patients. Late mortality occurred in 3 patients in group 1 from noncardiac causes and in 4 patients in group 2 from both cardiac and noncardiac causes. No patient had recurrent thromboembolism, and none in group 1 had recurrent symptoms. There was no echocardiographic evidence of lesion recurrence, and no tumor-related late mortality at a mean follow-up of 3 years.

	Comment

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This retrospective cohort study describes the surgical treatment of cardiac papillary fibroelastoma from a single cardiac surgical center. Even though improved clinical diagnosis has transformed cardiac papillary fibroelastoma from a postmortem to an antemortem diagnosis, there is still a significant incidence of underdiagnosis. In this study cardiac papillary fibroelastoma was discovered incidentally in 47% of patients. Edwards and colleagues [9] investigated primary cardiac tumors and reported that cardiac papillary fibroelastoma is the most common cardiac valve tumor, but because it is frequently asymptomatic the diagnosis can be missed.

Left heart cardiac papillary fibroelastoma frequently presents with embolic neurologic symptoms. In our study, this was the most common presentation in patients undergoing surgery primarily for this tumor, a finding that is consistent with other published reports [5, 6, 10]. Left heart tumors demonstrated a tendency for cerebral and retinal thromboembolism, and right heart tumors may pose this risk in the presence of a patent foramen ovale.

The tumor volume, the site of left heart tumors, and the valvular surface involved were not determinants of systemic thromboembolism. Gowda and colleagues [5] found an association between the size and mobility of cardiac papillary fibroelastoma and systemic thromboembolism, and suggested that tumors with a low risk of systemic thromboembolism could be managed conservatively with anticoagulation. However, there is evidence to suggest that the mechanism of thromboembolism is a combination of tumor embolization and thrombi formation on the tumor [6], so that a significant change in tumor size can occur over a short interval [11]. The tumor volume is a quantitative measure that correlates with the amount of tumor tissue (tumor burden) and a possible risk of thromboembolism better than the tumor size, which is a one-dimensional assessment of the tumor height [12]. The mean tumor volume in our patients who had thromboembolism was less than in those who did not, probably because patients lose tumor volume with episodes of embolism. Tumor size and/or tumor volume, therefore, would not necessarily be predictive of thromboembolism with cardiac papillary fibroelastoma.

Some studies have reported a higher incidence of systemic embolism for mitral valve than for aortic valve tumors [5], but this finding has not been corroborated by other series. We found no difference in the incidence of thromboembolism for both aortic and mitral cardiac papillary fibroelastoma, but rather an equivalent high risk of thromboembolism for left-sided valvular tumors (aortic, 43% and mitral, 43%) and a low risk for nonvalvular tumors (left ventricular outflow tract, 6% and all heart chambers, 0%). This finding of a high incidence of thromboembolism with valvular cardiac papillary fibroelastoma suggests that conservative management of left heart lesions may be associated with significant morbidity.

Right heart cardiac papillary fibroelastoma is rare and treatment is controversial [13]. Like left heart tumors, they have the potential for thromboembolism but without the risk of acute systemic embolism except in the presence of a patent foramen ovale. Right heart tumors should be excised in order to establish a definitive diagnosis and eliminate the risk of complications such as paradoxical embolism, which occurred in one of our patients and has been reported by others [14]. Pulmonary embolism and mechanical interference with valvular function have also been reported with right heart cardiac papillary fibroelastoma [13–15].

Cardiac papillary fibroelastoma demonstrates a high propensity to affect the anatomically contiguous structures of the aortic valve, the left ventricular outflow tract, and the anterior leaflet of the mitral valve. Cardiac papillary fibroelastoma has been reported in all the heart chambers and on all heart valves but the left heart is most often involved, with the aortic followed by the mitral valves [3, 5] being the most frequently affected. Since the common location of this tumor lies in the high flow and high pressure systemic outflow tract of the heart, the risk of thromboembolism is comparatively higher than that of the more common benign heart tumor, atrial myxoma. The surgical series of Tsukamoto and colleagues [16] and of Sugimoto and colleagues [17] reported incidences of 30% and 40%, respectively, for embolism with atrial myxoma; less than our finding (53%) for cardiac papillary fibroelastoma.

There are several hypotheses about the etiology of cardiac papillary fibroelastoma. Salyer and colleagues [18] suggested that fibroblasts infiltrate and proliferate within mural thrombi replacing them gradually with fibrous tissue. We previously reported the possible role of radiotherapy [19], and Grandmougin and colleagues [6] proposed that cytomegalovirus infection may underlie the development of cardiac papillary fibroelastoma. In our series, 19% of patients had concurrent hypertrophic obstructive cardiomyopathy, usually characterized by myocyte hypertrophy and disarray, and interstitial and endocardial fibrosis; histologic changes that may predispose to the development of cardiac papillary fibroelastoma. The possible pathogenetic relationship between both lesions needs to be further investigated.

We believe prompt surgical resection is warranted in all cases of cardiac papillary fibroelastoma because of potentially serious neurologic complications that may be associated with this cardiac tumor. However, comprehensive long-term studies of nonsurgical management of this tumor are not available. Klarich and colleagues [4] did report nine neurologic events in 37 patients followed for a mean of 31 months, and only one of these events was thought to be definitely related to cardiac papillary fibroelastoma. Surgical resection can be achieved by complete excision without an inclusive margin of normal tissue. A valve-sparing simple shave excision was adequate in almost all our patients, and valve replacement is only occasionally necessary for extensive tumors. Surgery is usually low risk and curative. No recurrence and late morbidity or mortality occurred in our patients during a follow-up period lasting up to 8.3 years.

As in all retrospective studies, our study has the inherent drawbacks of patient selection and recall biases, and incomplete data on some patients. Also, thromboembolism was diagnosed on the basis of symptoms so subclinical embolism such as minor pulmonary embolism and systemic embolism to other organs were not investigated. The incidence of thromboembolism associated with this tumor may, therefore, be underestimated. However, this study provides a large surgical experience with adequate data from which to draw conclusions on the clinical presentation, the surgical treatment, and outcome.

Cardiac papillary fibroelastoma demonstrates a high propensity to affect the anatomically contiguous structures of the aortic valve, the left ventricular outflow tract, and the anterior mitral leaflet. It is associated with a risk of systemic thromboembolism, particularly cerebral and retinal. As this lesion is not infrequently associated with other cardiac conditions, a careful echocardiographic examination is sometimes necessary for diagnosis. Cardiac fibroelastoma can be safely and effectively treated surgically, usually by simple shave excision, with good long-term results.

	Notice From the American Board of Thoracic Surgery Regarding Trainees and Candidates for Certification Who Are Called to Military Service Related to the War on Terrorism

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The Board appreciates the concern of those who have received emergency calls to military service. They may be assured that the Board will exercise the same sympathetic consideration as was given to candidates in recognition of their special contributions to their country during the Vietnam conflict and the Persian Gulf conflict with regard to applications, examinations, and interruption of training. If you have any questions about how this might affect you, please call the Board office at (312) 202-5900.

Timothy J. Gardner, MD

Chairman

The American Board of Thoracic Surgery

	References

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This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Personal Folders Download to citation manager Author home page(s): Dumbor L. Ngaage Charles J. Mullany Richard C. Daly Joseph A. Dearani William D. Edwards Christopher G.A. McGregor Thomas A. Orszulak Francisco J. Puga Hartzell V. Schaff Thoralf M. Sundt, III Kenton J. Zehr Permission Requests Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ngaage, D. L. Articles by Zehr, K. J. Search for Related Content PubMed PubMed Citation Articles by Ngaage, D. L. Articles by Zehr, K. J. Related Collections Cardiac - other