Porcine heterograft valve replacement in carcinoid heart disease

Carcinoid Heart Disease: A Review

Carcinoid heart disease remains a major cause of morbidity and mortality among patients with carcinoid syndrome and metastatic neuroendocrine tumors. Screening of all patients with N-terminal pro-B-type natriuretic peptide and transthoracic echocardiography is critical for early detection, as early symptoms and signs have low sensitivity for the disease. Cardiac surgery, in appropriate cases, is the only definitive therapy for advanced carcinoid heart disease, and it improves patient symptoms and survival. Management of carcinoid heart disease is complex, and multidisciplinary assessment of cardiac status, hormonal syndrome, and tumor burden is critical in guiding optimal timing of surgery.

Early and Late Outcomes of Surgical Treatment in Carcinoid Heart Disease

BACKGROUND

Symptoms and survival of patients with carcinoid syndrome have improved, but development of carcinoid heart disease (CaHD) continues to decrease survival.

OBJECTIVES

This study aimed to analyze patient outcomes after valve surgery for CaHD during a 27-year period at 1 institution to determine early and late outcomes and opportunities for improved patient care.

METHODS

We retrospectively studied the short-term and long-term outcomes of all consecutive patients with CaHD who underwent valve replacement at our institution between 1985 and 2012.

RESULTS

The records of 195 patients with CaHD were analyzed. Pre-operative New York Heart Association class was III or IV in 125 of 178 patients (70%). All had tricuspid valve replacement (159 bioprostheses, 36 mechanical), and 157 underwent a pulmonary valve operation. Other concomitant operations included mitral valve procedure (11%), aortic valve procedure (9%), patent foramen ovale or atrial septal defect closure (23%), cardiac metastasectomies or biopsy (4%), and simultaneous coronary artery bypass (11%). There were 20 perioperative deaths (10%); after 2000, perioperative mortality was 6%. Survival rates (95% confidence intervals) at 1, 5, and 10 years were 69% (63% to 76%), 35% (28% to 43%), and 24% (18% to 32%), respectively. Overall mortality was associated with older age, cytotoxic chemotherapy, and tobacco use; 75% of survivors had symptomatic improvement at follow-up. Presymptomatic valve operation was not associated with late survival benefit.

CONCLUSIONS

Operative mortality associated with valve replacement surgery for CaHD has decreased. Symptomatic and survival benefit is noted in most patients when CaHD is managed by an experienced multidisciplinary team.

Carcinoid heart disease: current understanding and future directions

Carcinoid tumors are rare and aggressive malignancies. A multitude of vasoactive agents are central to the systemic effects of these tumors. The additional burden of cardiac dysfunction heralds a steep decline in quality of life and survival. Unfortunately, by the time carcinoid syndrome surfaces clinically, the likelihood of cardiac involvement is 50%. Although medical therapies such as somatostatin analogues may provide some symptom relief, they offer no mortality benefit. On the other hand, referral to surgery following early detection has shown increased survival. The prompt recognition of this disease is therefore of the utmost importance.

Carcinoid valve disease

OPINION STATEMENT

Carcinoid is a rare neuroendocrine tumor that typically originates in the gastrointestinal tract and can result in a constellation of symptoms, mediated by vasoactive substances, referred to as carcinoid syndrome. Carcinoid valve and heart disease is characterized by the plaque-like, endocardial fibrous tissue deposits, primarily affecting the right heart endocardium and valves, which result as a consequence of the disease process. Potential mechanisms for the carcinoid valve disease include the complex role of excess serotonin and its interaction with serotonin receptors and transporters. Carcinoid valve and heart disease is a frequent occurrence in patients with carcinoid syndrome and is accountable for substantial morbidity and mortality. Cardiac surgery remains the most effective treatment option for carcinoid valve disease and a multidisciplinary approach at an experienced center is recommended for patients with metastatic carcinoid and carcinoid heart disease.

Carcinoid heart disease

Carcinoid tumors are rare, indolent neuroendocrine tumors that are often associated with a syndrome characterized by episodic flushing, secretory diarrhea, bronchospasm, and hypotension-the carcinoid syndrome. Cardiac involvement occurs in one-half to two-thirds of patients with carcinoid syndrome and is associated with a worse clinical outcome. Carcinoid heart disease is characterized by endocardial plaque-like deposits found predominantly on right-sided heart valves, leading to the combination of valvular stenosis and regurgitation. Left-sided cardiac involvement can also occur in <10% of patients. Somatostatin analogs form the therapeutic cornerstone in the medical management of these patients. Cytotoxic chemotherapy has had only limited success in the treatment of metastatic carcinoid tumors. Hepatic resection or palliative cytoreduction may be of benefit in patients with limited hepatic disease. Hepatic artery embolization is usually applied if a patient is not eligible for surgical debulking. The development and progression of carcinoid heart disease are associated with an unfavorable outcome. In those patients having severe cardiac involvement and well-controlled systemic disease, valve replacement surgery has been found to be an effective treatment that can both relieve intractable symptoms and contribute to improved clinical outcomes.

In patients with carcinoid syndrome undergoing valve replacement: will a biological valve have acceptable durability?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'In patients with carcinoid syndrome undergoing valve replacement, will a biological valve have acceptable durability?' Altogether, more than 130 papers were found using the reported search, of which 17 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The pooled data from all papers represent 51 patients with carcinoid right heart disease who underwent tricuspid valve replacement. Two 'outcomes' studies reported a 30-day postoperative mortality of 16.7-18% and 2-year survival rates of 44 and 50%, respectively. Seventeen patients were detailed in case reports. Of these 17 patients, 7 died during the follow-up period. All but one of these patients had a normal bioprosthesis at echocardiography or at post-mortem. One patient with a plaque-covered valve had a functionally normal valve. We conclude that at present, the best available evidence suggests that although 30-day mortality approaches 20%, approximately half of patients with carcinoid syndrome undergoing tricuspid valve replacement can be expected to survive 2 years. Some patients survive considerably longer than this, beyond 10 years in some cases. Importantly, at autopsy, many replacement valves have been shown to be normal, with a few patients reported as having died of cardiac causes. This should be taken as cautious evidence that biological valves have an acceptable lifespan in patients with carcinoid syndrome and that the process of valve destruction seen in carcinoid patients does not continue to a significant level in the bioprosthesis. Caveats to this include the lack of any directly comparative trial and the predominance of case reports as opposed to higher-level evidence.

Carcinoid heart disease

Progress in the medical and surgical management of patients with carcinoid disease has resulted in improved symptoms and survival. Carcinoid heart disease remains a major cause of morbidity and mortality among patients with malignant carcinoid syndrome. Limited medical treatment options are available for patients with symptomatic carcinoid heart disease. At the Mayo Clinic (Rochester, MN), we have taken an aggressive approach to severe valvular dysfunction from carcinoid heart disease. Patients with severe carcinoid heart disease currently are referred for cardiac operation when they develop cardiac symptoms, ventricular dysfunction, or (rarely) in anticipation of hepatic surgery. Surgical outcome depends on patient age and functional class at the time of cardiac surgery. Despite metastatic disease that limits longevity, cardiac surgical survivors usually demonstrate dramatic improvement in functional capacity. Cardiac surgery should be considered early for patients with symptomatic carcinoid heart disease and controlled carcinoid symptoms. An experienced medical, surgical, and anesthetic team approach to the patient with carcinoid heart disease is critical in order to provide state of the art management.

Carcinoid heart disease

Carcinoid heart disease is a rare form of valvular heart disease. The management of these patients is complex, as the systemic malignant disease and the cardiac involvement have to be considered at the same time. Progress in the treatment of patients with carcinoid disease has resulted in improved symptom control and survival. Development and progression of carcinoid heart disease are associated with increased morbidity and mortality. In patients with severe cardiac involvement and well-controlled systemic disease, cardiac surgery has been recognized as the only effective treatment option. Valve replacement surgery may not only be beneficial in terms of symptom relief, but may also contribute to the improved survival observed over the past 2 decades in patients with carcinoid heart disease. Early diagnosis and early surgical treatment in appropriately selected patients may provide the best results. In this article, we review the current literature regarding the biology, diagnosis, treatment, and prognosis of carcinoid heart disease.

Prediction of prognosis by echocardiography in patients with midgut carcinoid syndrome

BACKGROUND

The association between malignant midgut carcinoid tumours and right-sided cardiac lesions is well known, but the pathogenetic link between tumour secretion and valvular disease is still obscure. The purpose of this investigation was to describe the morphological and functional changes of valvular heart disease in a large patient series and to correlate these findings with hormonal secretion and prognosis.

METHODS

Of 64 consecutive patients with the midgut carcinoid syndrome followed between 1985 and 1998, valvular heart disease was evaluated in 52 patients by two-dimensional echocardiography, Doppler estimation of valvular regurgitation and flow profiles. A majority was also evaluated with exercise electrocardiography and spirometry.

RESULTS

Structural and functional abnormalities of the tricuspid valve were found in 65 per cent of patients, while only 19 per cent had pulmonary valve regurgitation. Long-term survival was related to excessive urinary excretion of 5-hydroxyindole acetic acid of over 500 micromol in 24 h, but the main predictor of prognosis was the presence of severe structural and functional abnormalities of the tricuspid valve. Although advanced tricuspid abnormalities were prevalent in this series, only one patient died from right ventricular heart failure.

CONCLUSION

Tricuspid valvular disease is a common manifestation of the midgut carcinoid syndrome and advanced changes are associated with poor long-term survival. Active surgical and medical therapy of the tumour disease reduced the hormonal secretion and, combined with cardiological surveillance, made right ventricular heart failure a rare cause of death in these patients.

Predictors of outcome of tricuspid valve replacement in carcinoid heart disease

The cardiac valvular surgical experience of patients in the Duke Carcinoid Database was reviewed to assess operative outcome. Of the 604 patients in the database, 19 patients with carcinoid heart disease were identified by cardiac catheterization or echocardiography, or both. Eight of these underwent tricuspid valve replacement surgery with bioprostheses (2 also had open pulmonic valvuloplasty). Compared with patients medically managed, surgically treated patients were similar with the exception that they had higher right atrial mean (17 +/- 6 vs 9 +/- 4 mm Hg, p = 0.03) and v-wave (27 +/- 6 vs 17 +/- 7 mm Hg, p = 0.04) pressures. Of the 8 surgical patients, 5 (63%) died within 30 days. Causes of death included tricuspid valve thrombosis, cerebral vascular accident, coagulopathy, renal failure, and intractable right heart failure. High comorbidity was present in all 8 patients. There was a weak trend (p = 0.17) toward lower Charlson comorbidity indexes in survivors (6.7 +/- 0.6) compared with nonsurvivors (7.6 +/- 0.9). Age was significantly lower (p = 0.036) in survivors (46 +/- 13 years) compared with nonsurvivors (69 +/- 4 years). Extended follow-up revealed 2 patients who survived beyond a decade. Review of 47 carcinoid valve replacement cases (Duke Carcinoid Database and 39 published cases) revealed a 30-day mortality of 56% for patients > 60 years of age, and 0% for those < or = 60 years of age (p < 0.0001). Although valve replacement surgery can afford prolonged palliation from carcinoid heart disease, it is associated with a significant mortality risk. Careful preoperative risk stratification by age and comorbidity may provide a means for optimal selection of surgical candidates.

Pathology of tricuspid valve stenosis and pure tricuspid regurgitation--Part I

This three-part article examines the histologic and morphologic basis for stenotic and purely regurgitant tricuspid valves. In Part I, conditions producing tricuspid valve stenosis are reviewed. In over 90% of stenotic tricuspid valves, the etiology is rheumatic disease. In isolated tricuspid stenosis, the etiology is either carcinoid or congenital. Rare causes of tricuspid stenosis include active infective endocarditis, metabolic or enzymatic abnormalities (Fabry's, Whipple's disease), and giant blood cysts.

Carcinoid heart disease: early failure of an allograft valve replacement

A woman who had carcinoid syndrome and carcinoid heart disease underwent tricuspid and pulmonary valve replacements with a xenograft and a cryopreserved allograft, respectively. Within 3 months of the operation severe pulmonary regurgitation and pulmonary hypertension refractory to medical therapy developed. Autopsy found the biomechanical tricuspid valve to be free of disease but the allograft in the pulmonary position was involved by carcinoid heart disease in a fashion similar to the excised native pulmonary valve.

Hypotension following valve replacement surgery in carcinoid heart disease

We report the use of adrenaline in a 62-year-old woman with carcinoid heart disease who underwent double valve replacement. She was given an intravenous infusion of octreotide throughout the peri-operative period. Following the termination of cardiopulmonary bypass she developed profound hypotension which proved to be refractory to various therapies but responded to adrenaline. Adrenaline is said to be contraindicated in carcinoid syndrome, but we would suggest the consideration of its use in such cases where the hypotension may result from myocardial depression rather than from a carcinoid crisis.

Transoesophageal echocardiography improves the diagnostic value of cardiac ultrasound in patients with carcinoid heart disease

Transthoracic and transoesophageal cardiac echocardiography and Doppler investigations were performed in 31 consecutive patients with malignant midgut carcinoid tumours. The transoesophageal images allowed measurement of the thickness of the atrioventricular valve leaflets and the superficial wall layers on the cavity side of both atria. The mean thickness of the anterior tricuspid leaflet was significantly greater than that of the mitral valve--a difference not seen in a control group of age-matched patients without carcinoid tumours and with normal cardiac ultrasound findings. In addition, the edges of the tricuspid leaflets were thickened giving them a clubbed appearance. Tricuspid incompetence was detected transoesophageally in 71% of the patients with carcinoid compared with 57% by transthoracic investigation. The inner layer of the right atrial wall in the carcinoid patients was significantly thicker than that of the left atrium and that of both atria in the controls. Furthermore, patients with other signs of severe carcinoid heart disease had significantly thicker mean right atrial luminal wall layer than those with less or no signs of right heart disease. Transoesophageal cardiac ultrasound investigation improved the diagnostic accuracy and seemed to show the structural changes typical of carcinoid heart disease established by histopathological investigations.

Surgical pathology of the tricuspid valve: a study of 363 cases spanning 25 years

Surgical pathologic features of the tricuspid valve were reviewed in 363 patients who had undergone tricuspid valve replacement at our institution during the period 1963 through 1987. Valves were purely regurgitant in 74%, stenotic and regurgitant in 23%, and purely stenotic in 2%; two valves were neither stenotic nor regurgitant. Among 269 purely insufficient tricuspid valves, the four most common causes were postinflammatory disease (41%), congenital disorder (32%), pulmonary venous hypertension (21%), and infective endocarditis (4%). Of 92 cases of tricuspid stenosis, with or without regurgitation, postinflammatory disease was observed in 92%. Female patients accounted for 66% of the 363 cases, including 84% of those with postinflammatory disease and 64% of those with pulmonary venous hypertension. In contrast, male patients accounted for 73% of cases with endocarditis and 61% with congenital heart disease. Although postinflammatory disease accounted for 53% of the 363 cases, its relative frequency diminished from 79% during 1963 through 1967 to only 24% during 1983 through 1987. This trend may reflect the decreasing incidence of acute rheumatic fever reported in Western countries. During the same time interval, the relative frequency of congenital heart disease as a cause of tricuspid dysfunction increased from 7% to 53%, and it is currently the most common cause in our surgical population. This finding apparently reflects changes in patient referral practices and the development of new operative procedures.

Cardiac valve prostheses: pathological and bioengineering considerations

Cardiac valve replacement with mechanical prosthetic or bioprosthetic devices enhances patient survival and quality of life. Nevertheless, prosthesis-associated complications are frequent and contribute significantly to outcome. Thromboembolic complications are the most important problems in patients with mechanical valves, necessitating chronic anticoagulation in all patients receiving them. In contrast, patients with bioprosthetic valves, composed of chemically treated animal tissues, generally do not require anticoagulants. However, bioprostheses fail frequently by degeneration, especially that involving cuspal calcification. This paper reviews the pathological and bioengineering considerations in the selection of cardiac prosthetic valves and the management of patients who have received these devices. The significance, morphology, and pathogenesis of the observed major complications and other alterations during function are described in detail. Contemporary investigative trends are summarized, including studies of inhibition of mineralization and other degenerative changes in bioprostheses, improved design rigid mechanical valves with pyrolytic carbon occluders and the development of central-flow, flexible polymeric leaflet valves.

Surgical management of carcinoid heart disease

Two female patients with carcinoid heart disease, ages 56 and 32 years, underwent pulmonic valve resection surgery and tricuspid valve replacement with a porcine bioprosthesis. Preoperatively, both patients were in function class 4 with severe right-side congestive failure and signs of tricuspid regurgitation and pulmonic stenosis. Both underwent surgery for porcine tricuspid valve replacement (33 and 31 mm valves) and pulmonic valve resection. Postoperatively, both patients had only minimal symptoms, including trace ankle edema and soft pulmonic murmurs, despite persistence of the systemic symptoms of carcinoid syndrome. Pre- and postoperative catheterization data documented hemodynamic improvements. One patient eventually died of hepatic failure due to metastatic disease. At autopsy, her bioprosthesis was free of carcinoid valvular changes.

The carcinoid syndrome: comparison of 21 necropsy subjects with carcinoid heart disease to 15 necropsy subjects without carcinoid heart disease

Carcinoid heart disease is a morphologically specific type of cardiac disorder that involves the mural and valvular endocardium on the right side of the heart. Twenty-one subjects (57 percent) (Group I) with carcinoid heart disease and 15 subjects (43 percent) (Group II) without carcinoid heart disease were studied at necropsy. The two groups were similar in mean age (54 years versus 55 years), duration of clinical illness (4.7 years versus 6.3 years), body weight (50 kg versus 52 kg), systemic blood pressure (117/77 mm Hg versus 128/77 mm Hg), blood hematocrit levels (37 percent versus 36 percent), total serum protein levels (6.0 g/dl), and serum albumin levels (2.2 g/dl versus 2.6 g/dl). The two groups were different in the frequency of the presence of precordial murmurs consistent with tricuspid regurgitation and/or pulmonic stenosis (95 percent versus 13 percent), cardiomegaly by chest radiography (38 percent versus 0), low voltage on electrocardiography (47 percent versus 0), and location of the primary site of the carcinoid tumor. Total electrocardiographic 12-lead QRS voltage was similar in each group (105 mm versus 132 mm) (10 mm = 1 mV). Of Group I subjects, 43 percent died of cardiac causes; none of the Group II subjects died of cardiac causes. Of the 21 subjects with carcinoid heart disease, seven had left-sided cardiac involvement, but in none was it of functional significance. Thus, although carcinoid heart disease frequently is the cause of death in patients with the carcinoid syndrome, the development of carcinoid heart disease is not related to the duration of symptoms of the carcinoid syndrome.

Surgical implications in malignant cardiac disease

Despite the rarity of primary malignant tumors of the heart (0.0017 to 0.03% of large postmortem series) and the infrequency of clinical signs and symptoms (0 to 50%) of the more common metastatic cardiac tumors, many cardiothoracic surgeons at some time will encounter a patient with one of these two conditions. A review of the medical literature yielded 28 cases of primary cardiac tumors, 10 of secondary tumors, and 12 of carcinoid heart disease treated surgically and followed sufficiently for retrospective evaluation. We summarized those cases and made the following conclusions. Primary malignant tumors of the heart are occasionally resectable, although cure is unlikely; survival may be enhanced by postoperative irradiation but probably not by postoperative chemotherapy. For patients with secondary malignant tumors of the heart, surgical intervention is rarely of benefit except for establishing a tissue diagnosis, effecting artificial cardiac pacing, decompressing symptomatic pericardial effusions, or reducing an obstructive tumor mass. Patients with carcinoid heart disease affecting the valves may derive benefit from valve replacement or repair. Thus, in selected patients with malignant cardiac disease, surgical intervention may be feasible and should always be among the therapeutic options considered.

Echocardiographic features of carcinoid heart disease

We reviewed the records of the Mayo Clinic patients with known carcinoid syndrome in whom echocardiographic studies had been done. Nineteen patients had M-mode and 2-dimensional echocardiographic examinations, and 1 patient had an M-mode examination only. Of the 20 patients, 8 had no evidence by echocardiogram of carcinoid heart disease; 2 had changes in the tricuspid valve echogram suggestive of early carcinoid heart disease, and the other 10 patients had the following distinctive echocardiographic findings: (1) the pattern of right ventricular volume overload (enlarged right ventricle with abnormal septal motion); (2) abnormal right-sided valves, including (a) a striking appearance of the tricuspid valve, the leaflets appearing thickened, retracted, and fixed in a semiopen position throughout the cardiac cycle, and (b) thickened, retracted pulmonic valve cusps, when visualized; and (3) the left-sided valves and chambers rarely involved. These echocardiographic features are distinctive of advanced carcinoid heart disease and correlate closely with pathologic findings.