Structural abnormalities of great arterial walls in congenital heart disease: light and electron microscopic analyses.

BACKGROUND: Great arteries in congenital heart disease (CHD) may dilate, become aneurysmal, or rupture. Little is known about medial abnormalities in these arterial walls. Accordingly, we studied 18 types of CHD in patients from neonates to older adults. METHODS AND RESULTS: Intraoperative biopsies from ascending aorta, paracoarctation aorta, truncus arteriosus, and pulmonary trunk in 86 patients were supplemented by 16 necropsy specimens. The 102 patients were 3 weeks to 81 years old (average, 32+/-6 years). Biopsies were examined by light (LM) and electron (EM) microscopy; necropsy specimens by LM. Positive aortic controls were from 15 Marfan patients. Negative aortic controls were from 11 coronary artery disease patients and 1 transplant donor. Nine biopsies from acquired trileaflet aortic stenosis were compared with biopsies from bicuspid aortic stenosis. Negative pulmonary trunk controls were from 7 coronary artery disease patients. A grading system consisted of negative controls and grades 1, 2, and 3 (positive controls) based on LM and EM examination of medial constituents. CONCLUSIONS: Medial abnormalities in ascending aorta, paracoarctation aorta, truncus arteriosus, and pulmonary trunk were prevalent in patients with a variety of forms of CHD encompassing a wide age range. Aortic abnormalities may predispose to dilatation, aneurysm, and rupture. Pulmonary trunk abnormalities may predispose to dilatation and aneurysm; hypertensive aneurysms may rupture. Pivotal questions are whether these abnormalities are inherent or acquired, whether CHD plays a causal or facilitating role, and whether genetic determinants are operative.

Diastolic dysfunction in patients with congenital heart disease.

As noted in the introduction of this article, a comprehensive evaluation of diastolic function in all known congenital heart defects is not feasible; however, by demonstrating several representative anatomic and genetic abnormalities where diastolic dysfunction may have clinical significance, it is hoped that scaffolding has been established which will provide structure for further study on this intriguing and influential component of function in patients with CHD. Understanding the contribution of diastole to overall ventricular function may be shown to have important implications in the recommendations for timing or potential benefit of surgical intervention. Or, to state differently, if diastolic dysfunction precedes that of systolic, would a rigorous analysis of diastole in the presurgical patient provide a more sensitive algorithm for intervention? The means for noninvasive assessment of diastolic function, primarily by spectral Doppler echocardiography, or using echocardiography in conjunction with other modalities, should allow for a comprehensive accrual of data in this patient population.

Chronic right-sided myocarditis mimicking arrhythmogenic right ventricular dysplasia.

Arrhythmogenic right ventricular dysplasia (ARVD) is a cause of right ventricular heart failure and has been implicated in some cases of sudden death in young adults. It is well known that a large majority of patients with ARVD have histological evidence suggestive of inflammation. Here we report a unique case of chronic myocarditis limited to the right ventricle and right side of the interventricular septum which presented clinically as ARVD. The fact that right sided myocarditis can clinically mimic the genetic disease of classic arrhythmogenic right ventricular dysplasia has therapeutic implications for the patient and relatives.

Batista procedure: elliptical modeling against spherical distention.

OBJECTIVE: Batista's cardio-reduction of mass and diameter changes the geometry of the left ventricle (LV). This in vivo study explores the LV changing from spherical distention to elliptic modeling. METHODS: Nineteen pigs were connected to cardio-pulmonary bypass (CPB), five of them without cardiac alteration (controls). The LV of the other fourteen pigs was incised between the left anterior descending and the circumflex arteries. Myocardial protection with the beating open method was used. In seven pigs, the LV incision was closed by direct suture to assess the surgical trauma of the Batista procedure (incision). In the other seven pigs a pericardial patch was placed for spherical distention of the LV as a model of heart failure (sphericalization). Patch removal and LV closure restored the normal cardiac geometry (elliptical modeling). Ventricular function was evaluated with Frank-Starling curves (stroke work index, SWI), with endsystolic elastance (EES) and diastolic compliance (beta(-1)) by impedance catheter, and with ejection fraction (EF) by transesophageal echocardiogram. Data were recorded after ventriculotomy, after sphericalization and after elliptical modeling (before and 30 min after discontinuation of CPB). RESULTS: CPB did not significantly alter controls' hemodynamic. Ventriculotomy decreased cardiac function (as % vs. post CPB-controls: SWI* 63 +/- 4; EES 93 +/- 2; beta(-1)* 86 +/- 5). Sphericalization additionally impaired the function (as % vs. ventriculotomy: SWI* 57 +/- 4; EES* 60 +/- 7; beta(-1)* 45 +/- 8). The elliptical modeling greatly improved ventricular performance (as % vs. sphericalization: SWI** 156 +/- 5; EES** 162 +/- 8; beta(-1)** 177 +/- 7; EF** 216 +/- 5) (P < 0.05 for Student's unpaired* and paired** t-test). CONCLUSIONS: Spherical distention of the left ventricular dimensions causes cardiac decompensation. The surgical trauma of the Batista procedure impairs the LV performance. However, the spherically distended LV benefits from Batista's cardio-reduction by elliptical modeling.

Microbubbles and mitral valve prostheses - transesophageal echocardiographic evaluation.

OBJECTIVE: To assess whether microbubbles are associated with a specific type of mitral valve prosthesis and to investigate the relationship of microbubbles to ventricular function and mitral regurgitation. One of the types of spontaneous echocardiographic contrast observed in patients with prosthetic heart valves has been described as microbubbles. METHODS: Clinical data and videotapes of patients with a prosthetic mitral valve who had undergone transesophageal echocardiography at the UCLA Medical Center between May 1989 and February 1995 were retrospectively reviewed. There were 109 studies (74 patients) available for review by two independent observers. RESULTS: Microbubbles occurred in 49 of the 66 studies of St. Jude valves ( 74%), eight of the 12 studies of Bjork Shiley valves (67%), four of four studies of Medtronic valves (100%) and zero of 23 studies of tissue valves (0%). Patients with an estimated ejection fraction greater than 45% were found to have a much higher likelihood of having microbubbles observed. There was no statistically significant association between the degree of mitral regurgitation and the observation of microbubbles. CONCLUSIONS: Microbubbles are a common phenomenon occurring in patients with mechanical mitral prostheses compared with tissue mitral valve prostheses. Their formation depends on the systolic ventricular function, suggesting a cavitation-like phenomenon participating in their formation perhaps due to the rate or velocity of the valve closure.

Eisenmenger syndrome in adults: ventricular septal defect, truncus arteriosus, univentricular heart.

OBJECTIVES: Morbidity and mortality patterns were characterized in adults with the Eisenmenger syndrome when two ventricles with a ventricular septal defect (VSD) joined two great arteries or one great artery, or when one ventricle joined two great arteries. BACKGROUND: Although afterload in these disorders differs, clinical differences have not been defined. METHODS: Seventy-seven patients were studied. Group A comprised 47 patients with VSD, aged 23 to 69 years (mean 39.5+/-10.2), follow-up 5 to 18 years (mean 7.2+/-4.9); group B, 14 patients with truncus arteriosus, aged 27 to 50 years (mean 33.7+/-7.3), follow-up 6 to 18 years (mean 7.7+/-5.1), and group C, 16 patients with univentricular heart, aged 18 to 44 years (mean 30.6+/-8.4), follow-up 5 to 15 years (mean 4.4+/-4.2). Echocardiography established the diagnoses and anatomic and hemodynamic features. Data were compiled on tachyarrhythmias, pregnancy, infective endocarditis, noncardiac surgery and the multisystem disorders of cyanotic adults. RESULTS: Thirty-five percent of the patients died. Sixty-three percent of deaths were sudden, and resulted from intrapulmonary hemorrhage, rupture of either the pulmonary trunk, ascending aorta or a bronchial artery, or vasospastic cerebral infarction, or the cause was unestablished. There were no documented tachyarrhythmic sudden deaths. CONCLUSIONS: Medical management of coexisting cardiac disease, multisystem systemic disorders, noncardiac surgery and pregnancy has reduced morbidity. Increased longevity exposed patients to proximal pulmonary arterial aneurysms, thromboses and calcification; to truncal valve stenosis and regurgitation; to semilunar and atrioventricular valve regurgitation, and to major risks of nontachyarrhythmic sudden death.

Prognostic value of dobutamine stress echocardiography in predicting cardiac events in patients with known or suspected coronary artery disease.

OBJECTIVES: The study sought to determine the utility of dobutamine stress echocardiography (DSE) in predicting cardiac events in the year after testing. BACKGROUND: Increasingly, DSE has been applied to risk stratification of patients. METHODS: Medical records of 1,183 consecutive patients who underwent DSE were reviewed. The cardiac events that occurred during the 12 months after DSE were tabulated: myocardial infarction (MI), cardiac death, percutaneous transluminal coronary angioplasty (PTCA), and coronary artery bypass surgery (CABG). Patient exclusions included organ transplant receipt or evaluation, recent PTCA, noncardiac death, and lack of follow-up. A positive stress echocardiogram (SE) was defined as new or worsened wall-motion abnormalities (WMAs) consistent with ischemia during DSE. Classification and regression tree (CART) analysis identified variables that best predicted future cardiac events. RESULTS: The average age was 68+/-12 years, with 338 women and 220 men. The overall cardiac event rate was 34% if SE was positive, and 10% if it was negative. The event rates for MI and death were 10% and 8%, respectively, if SE was positive, and 3% and 3%, respectively, if SE was negative. If an ischemic electrocardiogram (ECG) and a positive SE were present, the overall event rate was 42%, versus a 7% rate when ECG and SE were negative for ischemia. Rest WMA was the most useful variable in predicting future cardiac events using CART: 25% of patients with and 6% without a rest WMA had an event. Other important variables were a dobutamine EF <52.5%, a positive SE, an ischemic ECG response, history of hypertension and age. CONCLUSIONS: A positive SE provides useful prognostic information that is enhanced by also considering rest-wall motion, stress ECG response, and dobutamine EF.

Are high-velocity tricuspid and pulmonary regurgitation endocarditis risk substrates?

BACKGROUND: A major predisposing cause of infective endocarditis is a susceptible cardiac substrate characterized by high-velocity turbulent flow. However, the risk incurred by high-pressure, high-velocity regurgitation across inherently normal pulmonary and tricuspid valves has not hitherto been examined. METHODS AND RESULTS: This study focused on 186 adult patients with congenital heart disease who had pulmonary vascular disease and inherently normal right-sided pulmonary and tricuspid valves. The observation period was approximately 1646 patient-years. Exclusion criteria were coexisting lesions that might have served as independent risk substrates for infective endocarditis. High-velocity turbulent pulmonary and tricuspid regurgitation were identified and quantified by color flow imaging and continuous wave Doppler echocardiography. Diagnoses of infective endocarditis were based on established clinical and laboratory criteria. Tricuspid regurgitation was moderate to severe in 80 patients and mild or absent in 106 patients. Pulmonary regurgitation was moderate to severe in 84 patients and mild or absent in 102 patients. With the exception of a single habitual intravenous drug abuser, no patient, irrespective of the degree of high-velocity turbulent pulmonary or tricuspid regurgitation, had infective endocarditis. CONCLUSIONS: High-velocity turbulent flow across inherently normal pulmonary and tricuspid valves rendered incompetent by pulmonary hypertension may represent a relatively low-risk or no-risk substrate for infective endocarditis.

Safety and hemodynamic effects of intravenous triiodothyronine in advanced congestive heart failure.

Most patients with advanced congestive heart failure have altered thyroid hormone metabolism. A low triiodothyronine level is associated with impaired hemodynamics and is an independent predictor of poor survival. This study sought to evaluate safety and hemodynamic effects of short-term intravenous administration of triiodothyronine in patients with advanced heart failure. An intravenous bolus dose of triiodothyronine, with or without a 6- to 12-hour infusion (cumulative dose 0. 1 5 to 2.7 microg/kg), was administered to 23 patients with advanced heart failure (mean left ventricular ejection fraction 0.22 +/- 0.01). Cardiac rhythm and hemodynamic status were monitored for 12 hours, and basal metabolic rate by indirect calorimetry, echocardiographic parameters of systolic function and valvular regurgitation, thyroid hormone, and catecholamine levels were measured at baseline and at 4 to 6 hours. Triiodothyronine was well tolerated without episodes of ischemia or clinical arrhythmia. There was no significant change in heart rate or metabolic rate and there was minimal increase in core temperature. Cardiac output increased with a reduction in systemic vascular resistance in patients receiving the largest dose, consistent with a peripheral vasodilatory effect. Acute intravenous administration of triiodothyronine is well tolerated in patients with advanced heart failure, establishing the basis for further investigation into the safety and potential hemodynamic benefits of longer infusions, combined infusion with inotropic agents, oral triiodothyronine replacement therapy, and new triiodothyronine analogs.

Restoring the remodeled enlarged left ventricle: experimental benefits of in vivo porcine cardioreduction in the beating open heart.

Conceptual models have been used to assess the efficacy of cardioreduction (i.e., Batista procedure) because in vivo models were not available. This study reproduces an experimental angiographic model of heart failure by placing a large pericardial patch to sphericalize the left ventricle. Patch removal restored an elliptical normal cardiac shape. Cardioreduction was evaluated in 20 mini-pigs on cardiopulmonary bypass. Myocardial protection with a beating open method was used and cardioplegia was not used. Studies were made after an LV incision (i.e., circumflex marginal artery occlusion with the Batista incision). A large pericardial patch sphericalized the left ventricle, and LV closure by patch removal restored normal cardiac shape (ellipse). Ventricular function was evaluated by inscribing Starling curves to fill the heart systolic elastance (Ees, conductance catheter), and surface echocardiogram for fiber shortening. After defining LV function in normal hearts on bypass only, an LV incision to divide the median ramus circumflex artery was made. This ventriculotomy reduced stoke work (SW) 37% +/- 4%, but did not change elastance (Ees) or SW/end-diastolic volume (EDV) significantly. Using the LV incision function as control, patch placement reduced SW 33% +/- 4%, Ees 40% +/- 3%, and SW/EDV 44% +/- 7% and decreased fiber shortening 43% +/- 5% by echocardiogram. Patch removal restored stroke work, SW/EDV, and Ees, and echocardiograms returned to normal values after LV incision. Ventricular function after patch removal was unchanged when the beating open cardioprotective technique was used. We conclude that sphericalization of left ventricular dimensions by pericardial patch placement causes cardiac failure that is relieved by restoring the ellipsoid shape by patch removal. These findings support the value of restoration of an elliptical shape by surgical cardioreduction, when the beating open ventricle is used for myocardial protection.

The Fontan procedure in adults.

BACKGROUND: A retrospective clinical study was performed to document the course of adult patients undergoing the Fontan procedure. METHODS: Between 1982 and 1994, 21 adults aged 18 to 40 years (mean age, 27 +/- 7 years) underwent a Fontan procedure. Anatomic diagnosis was tricuspid atresia in 9, double-inlet left ventricle in 4, and various single ventricles in 8. Four underwent a right atria-right ventricle connection, 13 had a right atria-pulmonary artery connection, and 4 had a lateral-tunnel Fontan. Three of these 4 had a snare-adjustable atrial septal defect. Preoperative risk factors assessed were left ventricular end-diastolic pressure greater than 10 mm Hg, ejection fraction lower than 0.45, mean pulmonary artery pressure higher than 15 mm Hg, transpulmonary gradient greater than 10 mm Hg, pulmonary artery abnormalities, and atrioventricular valve regurgitation. Mean preoperative risk score was 1.6 /-1.1. Mean New York Heart Association class was 2.6 +/- 0.5. RESULTS: The operative mortality rate was 5% (1/21). Six patients (30%) had a major complication, four being prolonged effusions. One patient was lost to follow-up; the remaining 20 have been followed for a mean of 7.4 +/- 3.8 years. At follow-up, mean New York Heart Association class was 1.7 +/- 0.5. There has been one late death (5%) at 9 2/3 years, which was probably due to ventricular arrhythmia. Three patients (16%) have required and survived reoperation. During follow-up, 7 patients (37%) have had development of atrial arrhythmias requiring medication, and 2 have been treated for ventricular arrhythmias. CONCLUSIONS: These results indicate that properly selected adults can undergo the Fontan procedure with low morbidity and mortality. However, late-developing arrhythmias, need for reoperation, and decreasing ventricular function are serious problems that mandate careful follow-up.

Risks for and prevention of infective endocarditis.

It is accepted medical practice to prevent bacterial endocarditis in patients with susceptible congenital or acquired cardiac malformations who are likely to experience predictable procedure-related bacteremia. Patients in general, those with congenital heart disease specifically, are insufficiently aware of the need for such prophylaxis. It is responsibility of the physician to determine which patients are susceptible to endocarditis and the need for endocarditis prophylaxis for each patient for any given instance and to educate the patient as to this need. The American Heart Association provides wallet-sized cards that may be given to each patient. Those patients not previously known to have heart disease are, of course, not eligible for chemoprophylaxis. Because these represent many of the patients with endocarditis each year, it can be argued that only a minority of patients have preventable cases. Regarding the clinical application of anti-infective endocarditis prophylaxis, the American Heart Association gives this perspective: This statement represents recommended guidelines to supplement practitioners in the exercise of their clinical judgement and is not intended as a standard of care for all cases.... Because no adequate, controlled clinical trials of antibiotic regimens for the prevention of bacteria endocarditis in humans have been done, recommendations are based on vitro studies, clinical experience, data from experimental animal models, and assessment of both the bacteria most likely to produce bacteremia from a given site and those most likely to result in endocarditis. Bacterial endocarditis is one of the few infectious disease that almost always result in death unless treated. The dramatic nature of the morbidity and mortality of infective endocarditis in those so afflicted makes the prevention of even a few cases worth the effort.

Role of transthoracic and transesophageal echocardiography in diagnosis and management of infective endocarditis.

Echocardiography has become a mainstay in the diagnosis of endocarditis. Vegetations were first visualized noninvasively beginning with M-mode echocardiography in the mid-1970s. The evolution of echocardiography, to include first two-dimensional imaging and then Doppler imaging in the 1980s, established echocardiography as the noninvasive test of choice to evaluate for the presence of vegetations as well as for their sequelae. Most recently, the addition of transesophageal echocardiography has expanded the role and yield of echocardiography in diagnosing endocarditis as well as in guiding management.

Infective endocarditis in congenital heart disease.

The average life expectancy of patients with congenital heart disease has dramatically improved over the past four decades because of advances in medical and surgical therapy, with patients with complex lesions surviving to adolescence and adulthood. Tetralogy of Fallot, transposition of the great arteries, ventricular septal defects, patent ductus, and bicuspid aortic valves in particular are susceptible to infective endocarditis. Most operated patients are left with some form of residua or sequelae, many of which predispose to infective endocarditis. Surgical palliation, such as systemic-to-pulmonary shunts, and reparative surgery, often requiring prosthetic valve or conduit replacement, are major predisposing conditions. Accordingly, recognition, prevention, and treatment strategies for infective endocarditis assume increasing importance in adolescents and adults with congenital heart disease, operated or not.

Issues in surgical treatment of endocarditis including intraoperative and postoperative management.

Patients with infective endocarditis who require surgical intervention can be divided into four separate groups, in order of incidence: (1) patients with underlying acquired or congenital cardiac lesions or valvar abnormalities, (2) patients with preexisting prosthetic valves, (3) patients with nosocomial infections who are immunosuppressed, and (4) older patients with infection risk or patients with indwelling deep venous catheters. The surgical management for these individual groups and for specific valve lesions is discussed, along with illustrative case studies.

Myocardial myotonia in myotonic muscular dystrophy.

We sought to determine whether and to what degree myocardial myotonia might occur in myotonic muscular dystrophy. Cardiac involvement manifests itself chiefly as abnormalities of specialized tissues. Current echocardiographic techniques permit assessment of left ventricular diastolic filling properties and might detect subtle myocardial myotonia. Twenty patients (mean age 37 +/- 13 years) with myotonic muscular dystrophy were studied. Twenty normal subjects (mean age 34 +/- 12 years), served as controls. Each subject had two-dimensional targeted M-mode echocardiograms of the posterior left ventricular wall to measure the rate of early diastolic relaxation, which was defined as diastolic endocardial velocity maximum (DEVM). Global left ventricular function was quantified. Doppler recordings of mitral inflow measured peak E and A velocities, ratio of E to A (E/A), mitral deceleration time (DT) and isovolumic relaxation (IVR) time. Normal controls had DEVM = 19 +/- 3 cm/sec, IVR = 72 +/- 7 msec, E/A = 1.6 +/- 0.5, and DT = 193 +/- 18 msec. Two SDs below the mean normal DEVM was 13.3 cm/sec. Two patient groups emerged: group A (10 patients) had abnormally slow DEVM (< or = 13.2 cm/sec) and group B (10 patients) had normal DEVM (> 13.2 cm/sec) with DEVM = 11 +/- 2 cm/sec and 20 +/- 4 cm/sec, respectively. Mitral inflow parameters showed a longer DT and IVR, with lower E/A ratios for group A versus group B, with DT = 203 +/- 48 msec and 175 +/- 21 msec, IVR = 87 +/- 15 msec and 74 +/- 7 msec, E/A = 1.7 +/- 0.7 and 2.3 +/- 0.9, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Menstrual patterns in women with congenital heart disease.

To examine the extent to which congenital heart disease (CHD) influences ovarian function, 98 women (mean age 32.7 years) were asked to complete a mailed questionnaire regarding their menstrual patterns. Patients were divided into acyanotic (60%) and cyanotic (38.8%) groups. Cycle lengths, duration of menstrual cycle, regularity of menses, amount of flow, and breakthrough bleeding were compared in these two groups and against age-matched controls. The mean age of menarche for the sample (13.4 years) was significantly different (p < 0.004) when compared to their controls (12.5 years). With the exception of breakthrough bleeding, statistical differences were not found between the study population and the controls. When the menstrual histories of cyanotic women were compared with those of acyanotic women, differences were found for all categories of menstrual patterns with the exception of the amount of menstrual flow. Menstrual patterns of cyanotic women compared to controls were found to be significantly different for all categories with the exception of amount of flow. In general, women with CHD have menstrual patterns similar to those in the general population.

Pulmonary atresia with ventricular septal defect in adults.

BACKGROUND: Multistage surgery culminating in completed hemodynamic repair is now performed for pulmonary atresia with ventricular septal defect (PA-VSD). Justification for operation in patients with an adequate collateral pulmonary circulation is controversial. Data on natural adult survival are scant but are necessary to provide the rationale for multistage reconstructive procedures. METHODS AND RESULTS: All cyanotic adults with PA-VSD in the UCLA Adult Congenital Heart Disease Center Registry from 1978 through 1992 formed the basis for this study. Registry data and echocardiographic, hemodynamic, and angiographic information were used to determine longevity, clinical course, and operative feasibility. Of 26 patients, 16 were unoperated when referred (group A), and 10 had been palliated before age 18 years (group B). Two thirds were 18 to 29 years old. Only 2 patients survived beyond age 40 years. Six died during follow-up at a mean age of 31 years (+/- 12.1 SD). Eight group A patients were in New York Heart Association class II, and 8 were in class III. Of the 26 group A and B patients, 20 had aortic regurgitation, which was moderate or severe in 10. Eight had cardiac failure. Of 11 group A patients who remained unoperated, 5 died. Twelve patients were considered eligible for surgery at > or = 18 years of age. Ten underwent completed hemodynamic repair with a mean post-operative right ventricular-to-left ventricular systolic pressure ratio of 0.45 (+/- 0.16 SD), and there were no early or late deaths. CONCLUSIONS: Even when collateral blood flow permits adult survival, all such patients are symptomatic. Mean life expectancy without operation did not exceed three decades. Aortic regurgitation and cardiac failure are significant negative variables. Nearly half of unoperated adults died during follow-up. Staged hemodynamic repair can be performed with a low surgical risk in properly selected adults with PA/VSD.

Echocardiographic assessment of adults with tetralogy of Fallot.

Advances in medical and surgical management of congenital heart disease in the last three decades have resulted in a great many survivors to adulthood. Proper care requires intimate knowledge of the basic malformations and their surgical anatomy and results. Tetralogy of Fallot, the most common cyanotic malformation in adults, represents a spectrum from mild right ventricular outflow tract obstruction to complete pulmonary atresia. Evaluation of surgical residua and sequelae includes imaging of aortic-to-pulmonary arterial palliative shunts, detection of residual ventricular septal defect patch leaks or right ventricular outflow tract obstruction, definition of extracardiac conduit patency, and quantitation of ventricular function and valvular regurgitation. Refined echocardiographic imaging and hemodynamic definition is a mainstay in precise segmental anatomical and hemodynamic assessment. Transesophageal echocardiography is particularly important for intraoperative evaluation of surgical results.