66例三尖瓣置换术近、中期临床效果分析

目的：分析三尖瓣置换术的近、中期临床疗效,总结三尖瓣置换的临床经验。方法：回顾分析2010年1月—2015年12月我院66例三尖瓣置换的临床资料。根据病因分类,风湿性心脏病35例（其中因风湿性心脏病术后再次行三尖瓣置换12例）,先天性心脏病8例,感染性心内膜炎5例,瓣膜退行性病变4例,胸部外伤1例,起搏器安置术后1例。术前心功能分级（NYHA)II级者12例,III级者37例,心功能IV级者17例,56例患者行生物瓣置换,10例行机械瓣置换。结果：66例患者中,住院期间死亡4例,其中2例死于严重心力衰竭,1例死于心律失常,1例死于多脏器功能衰竭,2例出现III度房室传导阻滞,予置入永久起搏器。术后随访3~60月,随访期间死亡1例,全组总死亡率：7.5%。术后心功能恢复至I级26例,II级35例,III级5例。结论：三尖瓣置换术早期死亡率较高,所以只有病变严重者才考虑行置换手术且须严格掌握三尖瓣置换指征。我院三尖瓣置换患者,近、中期效果是满意的,远期效果尚待观察。     

Triple valve replacement with bileaflet mechanical valves: is the mechanical valve the proper choice for the tricuspid position?

A more durable mechanical valve may be a better choice for the tricuspid position than a bioprosthesis when the patient already has mechanical prosthesis in the left side of the heart. Eleven cases of triple valve replacement (total follow-up period, 49.5 patient years), all with mechanical valves, are reviewed to assess optimal valve selection. Nine patients had undergone a total of 12 previous cardiac surgeries. Three patients died in hospital (27.3%), but there were no late deaths among the survivors. Two cases of valve thrombosis in the tricuspid position occurred (linearized incidence: 4.04%/patient years) and 1 of these required reoperation. Because of this high incidence of valve thrombosis, the bileaflet mechanical valve is not considered to be the best choice. Even if mechanical valves are implanted in the left side of the heart, a bioprosthesis may be a better choice at the tricuspid position.     

三尖瓣置换术连续11例手术治疗成功

安贞医院自１９９０年２月至１９９３年６月共实施各种三尖瓣手术２２９例。其中三尖瓣成形２１８例，三尖瓣置换１１例、占４％；其中男性３例、女性８例、平均年龄３２．６岁，心功能均在Ⅲ级以上，先天性心脏病Ｅｂｓｔｅｉｎ１例，三尖瓣发育不全２例，后天性心脏病中风心病６例、心内膜炎２例、均做了三尖瓣置换术，原位置换８例、房位置换３例、全部保留瓣膜６例，保留隔瓣４例，仅１例切除瓣膜，共用ＳｔＪｕｄｅ机械瓣９枚，牛心包瓣２枚。本文就三尖瓣置换术的适应征进行了探讨，认为在三尖瓣瓣叶尤其是前叶病理改变严重，或三尖瓣成形术后仍有关闭不全者应行换瓣手术。并就手术具体方法进行了改进：（１）风心病进行ＴＶＲ手术时应行原位瓣膜替换，自隔瓣根部稍上方进针，褥式带垫片缝合避免损伤传导束对前后瓣则行连续缝合；（２）对三尖瓣隔瓣发育不全者则行房位置换；（３）术中尽量多的保留三尖瓣及其附属装置；（４）本组选用中心血流，并且抗血栓性较好的生物瓣或双叶机械瓣。本组１１例术后无死亡，无并发症，随诊无心律失常。     

Failure of balloon dilatation of the pulmonary valve in carcinoid pulmonary stenosis.

BACKGROUND--Carcinoid heart disease typically results in pulmonary stenosis and tricuspid incompetence. Percutaneous balloon dilatation is an effective treatment for congenital pulmonary stenosis and has been applied successfully to tricuspid stenosis caused by carcinoid heart disease. The value of balloon dilatation of the pulmonary valve in carcinoid pulmonary stenosis was assessed. METHODS--Two patients with severe congestive heart failure secondary to carcinoid heart disease and with documented pulmonary stenosis had balloon dilatation of the pulmonary valve. In both cases tricuspid regurgitation was also present together with reduced cardiac output. RESULTS--The procedure was technically successful in both patients. One patient experienced symptomatic benefit for two months and the other experienced no improvement. Both patients subsequently required combined tricuspid and pulmonary valve replacement from which good results and symptomatic improvement were obtained. CONCLUSION--Though balloon dilatation of the pulmonary valve is technically feasible it is unlikely to provide useful palliation in carcinoid heart disease. Valve surgery should be considered in patients in whom the malignancy is controlled but carcinoid heart disease is producing drug resistant congestive heart failure.     

Carcinoid heart disease Report of a case treated by open heart surgery

Carcinoid heart disease may develop in patients with long-standing carcinoid syndrome. The cardiac lesions often are multiple, and with rare exceptions only the right side of the heart is involved. The patient with carcinoid tumor may do well for many years but deteriorate rapidly because of acquired valvular heart disease. A patient is presented with known carcinoid syndrome for 19 years and rapidly progressive right failure of five months' duration. Cardiac catheterization studies revealed the presence of pulmonary valvular stenosis and tricuspid insufficiency. Valvulotomy was performed on the fibrocartilagenous pulmonary valve under extracorporeal circulation, and the tricuspid insufficiency was treated by annuloplasty. Because of the gross deformity and deficiency of tricuspid valve tissue, it was impossible adequately to correct the insufficiency, and the patient died in the early postoperative period.     

Clinical, echocardiographic and evolutive aspects of right atrial thrombosis

The clinical and echocardiographic features of right atrial thrombi were examined in 9 patients, 5 men and 4 women aged 16 to 86 years. The 2D echocardiographic diagnosis was confirmed at autopsy (4 cases) or by the association of severe recurrent pulmonary embolism (5 cases). Three patients had associated ischaemic heart disease and on patient had dilated cardiomyopathy. The clinical presentation was: acute cor pulmonale (5 cases including 2 patients which biventricular myocardial infarction), chronic post-embolic cor pulmonale (1 case), tricuspid valve obstruction (1 case), general ill health with pyrexia (1 case) and heparin-induced thrombocytopenia (1 case). Predisposing factors included: absence of anticoagulent therapy (7 cases), previous supraventricular arrhythmias (2 cases) and right ventricular failure (6 cases, including 2 of right ventricular infarction). In 2 patients the thrombi were relatively immobile and had a wide base of implantation on the interatrial septum; in 1 patient, multiple thrombi were observed lining the right heart cavities from the inferior vena cava to the pulmonary infundibulum. In the other 6 patients, the thrombi were very mobile with a visible pedicule of implantation (2 cases) or totally free (4 cases). The variable polylobulated appearances, completely irregular whirling motion and intermittent prolapse into the tricuspid valve were characteristic features of the latter 4 cases. They disappeared spontaneously (2 cases) or after fibrinolytic therapy (2 cases) in under 36 hours. Three patients were operated with one postoperative death. The global hospital mortality was 22%. The present occasional detection of right atrial thrombosis will certainly become more common if patients with pulmonary embolism, right ventricular infarction or deep venous thrombosis are systematically examined by 2D echocardiography in the acute phase of their illness.     

The clinical spectrum of tricuspid regurgitation detected by pulsed Doppler echocardiography

The clinical diagnosis of tricuspid regurgitation (TR) is often difficult. Two-dimensional pulsed Doppler echocardiography offers a sensitive and specific method for detecting and semi-quantitating tricuspid regurgitation. The clinical, radiographic, radionuclide, echocardiographic, and when available, the right cardiac catheterization findings were evaluated in 36 patients with a diagnosis of tricuspid regurgitation by pulsed Doppler. Ten healthy subjects served as controls. The underlying cardiac cause was rheumatic heart disease in 7 (20%), ischemic heart disease in 12 (33%), dilated cardiomyopathy in 5 (14%), hypertensive heart disease in 2 (5%), aortic valve stenosis and/or regurgitation in 3 (8%), mitral valve prolapse with mitral regurgitation in 1 (3%), and congenital heart disease in 6 (17%). Seven patients (19%) had a temporary or permanent transvenous right ventricular pacing wire. A systolic murmur was heard in 29 patients (81%) with 16 (46%) having an elevated jugular venous pressure. Tricuspid regurgitation was clinically suspected in only 2 patients (6%). Isolated tricuspid regurgitation was uncommon, seen in 6 patients (17%), and usually secondary to congenital heart disease, ischemic heart disease, with the use of a transvenous pacing wire and following mitral valve replacement. Right cardiac catheterization was performed in 10 patients, of which 7 demonstrated elevated right atrial and pulmonary artery pressure. Pulsed Doppler echocardiography offers a practical and accurate method of detecting and evaluating the severity of tricuspid regurgitation. Tricuspid regurgitation is generally a functional disorder, and frequently occurs in association with left sided valvular heart disease, cardiomyopathy or congenital heart disease.     

Failure of balloon dilatation of the pulmonary valve in carcinoid pulmonary stenosis.

BACKGROUND--Carcinoid heart disease typically results in pulmonary stenosis and tricuspid incompetence. Percutaneous balloon dilatation is an effective treatment for congenital pulmonary stenosis and has been applied successfully to tricuspid stenosis caused by carcinoid heart disease. The value of balloon dilatation of the pulmonary valve in carcinoid pulmonary stenosis was assessed. METHODS--Two patients with severe congestive heart failure secondary to carcinoid heart disease and with documented pulmonary stenosis had balloon dilatation of the pulmonary valve. In both cases tricuspid regurgitation was also present together with reduced cardiac output. RESULTS--The procedure was technically successful in both patients. One patient experienced symptomatic benefit for two months and the other experienced no improvement. Both patients subsequently required combined tricuspid and pulmonary valve replacement from which good results and symptomatic improvement were obtained. CONCLUSION--Though balloon dilatation of the pulmonary valve is technically feasible it is unlikely to provide useful palliation in carcinoid heart disease. Valve surgery should be considered in patients in whom the malignancy is controlled but carcinoid heart disease is producing drug resistant congestive heart failure.     

Echocardiographic spectrum of Ebstein's anomaly of the tricuspid valve.

Sixteen patients aged between one day to 18 years with Ebstein's malformation of the tricuspid valve were studied with ultrasound. The findings were compared with a group of 74 patients without Ebstein's malformation. Two features were considered specific for Ebstein's malformation: 1) ability to record the anterior tricuspid leaflet (ATL) farther to the left of the left sternal border than in the control group; and 2) abnormally prolonged interval between the "C" points of the tricuspid and the mitral valve echoes (McTcI). All other parameters measured were nonspecific for Ebstein's anomaly of the tricuspid valve. The sail sound was recorded in ten patients with Ebstein's malformation and occurred at the time when the anterior tricuspid leaflet was in the most posterior position. In a patient with congenital heart disease, an McTc interval greater than 0.03 sec and recording of an anterior tricuspid leaflet near the apex of the heart strongly suggest the diagnosis of Ebstein's malformation. These two criteria were not fulfilled in any patient who did not have Ebstein's malformation. Conversely, however, absence of these two features does not rule out Ebstein's anomaly of the tricuspid valve.     

Two dimensional echocardiography and the tricuspid valve. Leaflet definition and prolapse.

The tricuspid valve was studied in 143 subjects using two dimensional echocardiography. The groups studied were 40 normal subjects, 31 patients with mitral valve prolapse, 22 with clinically probable tricuspid valve prolapse, 20 with congestive cardiac failure, and 30 with miscellaneous cardiac conditions but no features of right heart disease. Using multiple views it was possible to record all three leaflets in 74.8% of cases and anterior and septal leaflets in 95%. Prolapse of the tricuspid valve was recognised in 13 patients: six (19.5%) of the group with mitral valve prolapse and seven (6%) of the remaining patients. Prolapse of all three leaflets was shown in one patient, anterior and septal prolapse in six patients, anterior and posterior in three patients, septal leaflet prolapse alone in two patients, and anterior alone in one patient. Two dimensional echocardiography allows definition of individual tricuspid leaflets and prolapse of any or all leaflets can be diagnosed. Tricuspid valve prolapse is commonly associated with prolapse of mitral valve leaflets but isolated cases are recognised.     

三尖瓣替换术及其早期死亡原因探讨

三尖瓣替换术，由于其手术死亡率高，一般只有在三尖瓣成形术无法成功的情况下才予施行。我院自１９８６年１月至１９９４年１０月，连续进行了７００例心脏瓣膜替换术，其中１７例（２．４３％）患者接受了三尖瓣替换术。１７例中１２例为风湿性心脏病患者，４例为Ｅｂｓｔｅｉｎ畸形，余１例为右房恶性间皮瘤。本组术后早期死亡５例（２９．４％），死亡原因主要是术后广泛渗血、严重低心输出量综合征、急性肾功能衰竭和恶性心律失常。     

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.     

Echocardiographic Assessment of Juxtaposition of the Right Atrial Appendage in Children with Congenital Heart Disease

The objective of this study was to analyze the echocardiographic characteristics of juxtaposition of the atrial appendages and to determine its prevalence in children with congenital heart disease. From June 1998 to December 2008, 10,880 children underwent selective angiocardiography, magnetic resonance imaging (MRI), and echocardiography for evaluation of congenital heart disease. Juxtaposition of the atrial appendages was diagnosed based on the results of angiocardiography and MRI; the echocardiographic characteristics of this anomaly were analyzed retrospectively. There were 33 patients diagnosed with juxtaposition of the right atrial appendage (JRAA); no patient was diagnosed with juxtaposition of the left atrial appendage. The prevalence of JRAA in children with congenital heart disease was 0.30%. JRAA and abnormal spatial orientation of the atrial septum were visualized by Doppler echocardiography in 28 cases. In the remaining five cases, three cases with suspected JRAA could not be determined by echocardiography and the diagnosis was missed in two cases. The most common associated anomalies were conotruncal malformations (16 cases with double outlet of the right ventricle, 9 cases with pulmonary atresia, 6 cases with transposition of the great arteries, 1 case with tetralogy of Fallot) and tricuspid malformations (6 cases with tricuspid straddling, 3 cases with tricuspid atresia, 2 cases with tricuspid valve stenosis). Based on the characteristic alteration of the plane of the atrial septum and visualization of the malpositioned right atrial appendage, JRAA can be accurately diagnosed by Doppler echocardiography. (Echocardiography 2010;27:878‐884)     

Severe symptomatic tricuspid valve regurgitation due to permanent pacemaker or implantable cardioverter-defibrillator leads

OBJECTIVES: We report a series of patients with severe tricuspid valve regurgitation due to a permanent pacemaker (PPM) or implantable cardioverter-defibrillator (ICD) lead. BACKGROUND: Severe tricuspid regurgitation caused by a PPM or ICD lead is an under-recognized but treatable etiology of severe right heart failure. METHODS: We reviewed the records of 41 patients who underwent tricuspid valve operation for severe tricuspid regurgitation caused by previously placed PPM or ICD leads. RESULTS: During surgery, severe tricuspid regurgitation was found to be caused by the PPM or ICD leads in all 41 patients. There was a perforation of the tricuspid valve leaflet by the PPM or ICD lead in 7 patients, lead entanglement in the tricuspid valve occurred in 4 patients, lead impingement of the tricuspid valve leaflets occurred in 16 patients, and lead adherence to the tricuspid valve occurred in 14 patients. The septal leaflet was most often perforated (6 of 7). In the preoperative evaluation, valve malfunction due to the PPM or ICD lead was diagnosed preoperatively in only 5 of 41 (12%) patients by transthoracic echocardiography. All patients underwent successful tricuspid valve operation (22 tricuspid valve replacement), with one perioperative death occurring. During follow-up (range, 1 to 99 months), there was one patient who died from left-sided heart failure and three patients died of other causes. The remaining patients showed improvement in signs and symptoms of heart failure. CONCLUSIONS: Damage to the tricuspid valve by PPM or ICD leads may result in severe symptomatic tricuspid regurgitation and may not be overtly visualized by echocardiography. This etiology should be considered when evaluating patients with severe right heart failure after PPM or ICD implantation.     

Cardiac pacemakers in children. 15 years' experience

Between 1971 and 1986, 85 pacemakers were implanted at the St Justine Hospital, Montreal, in 57 young patients (25 girls, 32 boys) then aged from one day to 23 years (mean 10.3 years). The patients were followed up for periods ranging from 15 days to 13.5 years (mean 4.5 years); 119 epicardial electrodes were positioned by thoracotomy in 52 patients and by sternotomy in 5 patients; the 85 pacemaker cases were placed in the left retroperitoneal cavity. The pacemakers were programmed in modes VVI (28), AAI (1) and DDD (28). The indications for pacemaker implantation were: complete atrioventricular block in 39 cases (postoperative 16, congenital 22, acquired 1), sinus node disease in 17 cases (postoperative 13, cardiomyopathy 3, normal heart 1) and Romano-Ward syndrome in 1 case. Operated heart diseases which required pacemaker implantation were: D-transposition of the great arteries in 17 cases (complete atrioventricular block 7, sinus node disease 10), tricuspid valve atresia in 3 cases (sinus node disease 3) and tetralogy of Fallot in 3 cases (complete atrioventricular block 3). Twenty-four patients underwent a total of 33 reoperations: 21 changes of battery, 12 changes of electrodes (6 for fibrosis, 6 for breakage). Only one patient developed infection of the pacemaker case. Altogether, the incidence of complications (infection and/or breakage) was low in this series, regardless of the pacing mode. Pacing in children is now an acceptable treatment with low risk provided the indications are well selected.     

复发性心脏瓣膜病再次外科治疗效果及其相关因素

目的:回顾性分析对二尖瓣闭式扩张术、瓣膜成形术、瓣周漏、人工机械瓣功能障碍、生物瓣衰坏等原因引起的复发性瓣膜病变进行再次手术的效果和相关因素。方法: 复发性瓣膜病患者331（男143,女188）例,年龄12～73(46±12)岁,两次手术间隔时间2月～25(17±8)年。其中二尖瓣闭式扩张术后再狭窄143例,二尖瓣或主动脉瓣成形术后瓣膜病变复发53例,生物瓣衰坏32例,瓣周漏26例,换瓣术后其它瓣膜病21例,人工瓣膜替换或瓣膜成形术后心内膜炎17例, Ebstein畸形矫治术后三尖瓣关闭不全15例,人工瓣膜机械功能故障9例,室间隔缺损修补术并行瓣膜成形术后心内膜炎7例,完全或部分性心内膜垫缺损和矫正性大动脉转位术后二尖瓣或三尖瓣关闭不全6 例,二尖瓣球囊扩张术2例。再次手术方式为二尖瓣替换术,主动脉瓣替换术,二尖瓣和主动脉瓣替换术,三尖瓣替换术,瓣周漏修补术及三尖瓣成形术等。结果: 全组共死亡27例,占8.2％,早期主要死亡原因为低心排出量综合征、室性心律失常、多脏器功能衰竭、左心室破裂、感染性心内膜炎、肾功能衰竭。随访259例,随访期6月～21（10±7）年,心功能恢复至Ⅰ～Ⅱ级189例。复发性心脏瓣膜病再次手术的危险因素包括术前心功能差、重要脏器功能不全、急诊手术、主动脉阻断时间和体外循环时间长等。结论: 针对再手术相关的危险因素进行积极防治,适时而妥善的外科手术和围手术期处理仍可获良好效果。     

An optimized contrast echocardiographic method for the detection and quantification of tricuspid valve insufficiency

In 47 patients the incidence and extent of tricuspid insufficiency (TI) was determined by two different contrast echocardiographic methods. In 18 patients severe mitral stenosis, in 7 patients combined mitral valve disease and in 6 patients severe mitral insufficiency were diagnosed by cardiac catheterisation. 3 patients had mitral and aortic insufficiency, one patient severe aortic stenosis and 2 patients aortic insufficiency. In 9 patients the study was performed after mitral valve replacement, in 1 patient after aortic valve replacement. 1 patient had no valvular heart disease. All patients underwent right heart catheterisation and biplane cineventriculography of the right ventricle within two days of echocardiography. Method A: Echocardiography of the inferior vena cava. Method B: Direct contrast echocardiography of the tricuspid valve in the short parasternal plane. Compared with the hemodynamic study, sensitivity of method A was 62% and specificity 89% in detection of TI. Both the sensitivity and specificity of method B were 100%. A TI grade I was diagnosed in 6 of 10 patients with method A and in 9 of 10 patients with method B, a TI grade II in 8 of 9 patients with method A and in 10 with method B. A severe TI (III) was diagnosed in only 4 of 7 patients with method A and in all 7 patients with method B. The results suggest that direct contrast echocardiography of the tricuspid valve in patients with rheumatic valve disease is a highly sensitive and specific method in detection and quantification of TI in comparison to the vena cava method.     

Idiopathic annular dilation: a rare cause of isolated severe tricuspid regurgitation

The management of patients with severe tricuspid regurgitation (TR) requires the clinician to clarify the mechanism of regurgitation. Primary disorders of the tricuspid valve, either congenital or acquired, may be readily identified by echocardiography. Severe TR most often results from left-sided heart disease and secondary pulmonary hypertension. Cardiomyopathic processes may also cause right ventricular failure and functional TR. We report three patients with severe TR due to idiopathic annular dilation. The tricuspid valves were otherwise normal on surgical inspection, and the pulmonary pressures were not significantly elevated. Each patient was aged over 65 years and had chronic atrial fibrillation with preserved left ventricular systolic function. Surgical treatment was associated with marked clinical improvement. Clinicians should recognize this unusual but treatable cause of right-sided congestive heart failure.     

儿童机械瓣膜置换术121例的疗效

目的探讨儿童机械瓣膜置换术的疗效。方法14岁以下病童施行心脏机械瓣膜置换术121例,先天性心瓣膜病89例,风湿性心瓣膜病29例,心内膜炎24例(其中21例为先天性或风湿性心脏病患儿)。行二尖瓣置换62例,主动脉瓣置换49例,三尖瓣置换6例,双瓣置换4例。共置换机械瓣膜125枚。术后患儿均接受华法林抗凝。术后随访通过问卷或门诊检查完成。结果住院死亡15例,病死率12．4％(15／121);失随访32例。74例平均随访时间10．5年,晚期死亡1例,再手术2例。大部分存活病人心功能(纽约心脏协会分级)Ⅰ级-Ⅱ级。结论大多数儿童可以植入较大规格的机械瓣膜,保证远期生长发育需要。儿童机械瓣膜置换住院病死率高,合理的抗凝治疗可能提高远期疗效。     

Two-dimensional echocardiography in the diagnosis of carcinoid heart disease

Tricuspid valve disease accounts for significant morbidity and mortality in the carcinoid syndrome, but M-mode echocardiography is often insensitive in completely defining the tricuspid valve. We performed two-dimensional echocardiography (2DE) in seven patients with proven carcinoid syndrome. There were five males and two females whose ages ranged from 53 to 79 years. The carcinoid syndrome had been present by symptoms for 12 to 84 months and by 5-HIAA levels for 6 to 84 months prior to 2DE. Short, thickened, immobile tricuspid valve leaflets, fixed in a partially open position, were visualized in two patients and confirmed in one patient at surgery. Tricuspid regurgitation was demonstrated angiographically in one and by contrast 2DE in the other. A third patient had clinical evidence of tricuspid stenosis with a doming tricuspid valve on 2DE. The motion of the tricuspid value viewed in real time was clearly distinct in these two situations. Four patients had both normal M-mode and 2DE studies despite the fact that clinical and biochemical evidence of carcinoid disease had been present for equally long periods of time. The tricuspid valve was best visualized in the parasternal right ventricular long-axis and short-axis views. The apical four-chamber view was less helpful. Thus, 2DE demonstrated specific tricuspid valve abnormalities in the carcinoid syndrome with thickening, shortening, and immobility of the leaflets when valvular regurgitation was present and thickening and doming when the valve was stenotic. 2DE should be a useful method in the diagnosis and sequential evaluation of patients with carcinoid heart disease.