Intracardiac pheochromocytoma with dual coronary blood supply: case report and literature review.

An intracardiac pheochromocytoma is extremely rare. This patient first presented postpartum at age 28 with clinical signs, symptoms and biochemical evidence suspicious for the diagnosis of pheochromocytoma. Multiple radiologic studies and laparotomy failed to confirm the diagnosis. Some 20 years later the patient presented with complaints of chest pain, palpitations, and flushing. Cardiac catheterization demonstrated a 'tumor blush' superior to the left atrium with a blood supply derived from the coronary arteries. Open-heart surgery was performed and the tumor successfully removed.

Spectroscopy of the isolated rabbit heart: effects of perfusion with oxygenated crystalloid cardioplegia at 4 degrees C and 20 degrees C.

Factors that limit survival of explanted cardiac allografts include intracellular acidosis and loss of high energy phosphates. This study was undertaken to determine if these processes could be retarded by specific interventions during organ storage and to determine the capabilities of phosphorus-31 (31P) nuclear magnetic resonance spectroscopy to monitor these intracellular changes noninvasively. Thirty-six excised rabbit hearts were studied in six groups according to the storage temperature and conditions of their perfusion: nonperfused, aerated perfusate or oxygenated perfusate, each at 4 degrees C and 20 degrees C. 31P spectra were continuously obtained starting 20 mins post explanation and continuing for at least 5 h. The resulting data were analyzed to determine metabolite concentration and intracellular pH. The phosphodiesters, inorganic phosphates and phosphomonoesters, as well as the phosphocreatine and adenosine triphosphate peaks, could be reproducibly resolved. Comparisons at 0.5, 1, 2, 3, 4, and 5 h indicated that high energy phosphates were the most quickly degraded, and intracellular acidosis progressed most rapidly in nonperfused hearts at 20 degrees C. Hearts perfused with oxygenated cardioplegic solution at 4 degrees C showed significantly prolonged preservation of high energy phosphates and delayed development of intracellular acidosis. It was concluded that continuous infusion of oxygenated cardioplegic solution improves preservation of high energy phosphates at low temperatures, and that 31P magnetic resonance spectroscopy can be used to monitor these important intracellular changes rapidly and nonivasively, permitting serial studies on the same heart. This technique substantially reduced the number of animals needed for the study (36 were used in this study rather than the 216 required by traditional techniques).

Deposits of crystalline material containing silicon in surgically excised human valves.

Ninety-seven surgically excised natural cardiac valves were examined by scanning electron microscopy and x-ray energy spectroscopy to assess the occurrence of crystalline deposits that contain the element silicon. Valves examined included 33 mitral valves, 63 aortic valves, and 1 tricuspid valve. To reduce the possibility of surface contamination, the deep layers of some valves were examined after exposure by fracture of the valve. Crystalline material containing silicon was observed in the deep tissue. Such crystalline material was sometimes entwined within subendothelial fibers. Crystalline deposits that contained silicon were associated with 34 of 97 of these valves (35%). Among the 34 valves that showed silicon, 24 (71%) also showed microdeposits of calcific material. In view of evidence that silicon may participate in the calcification of bone, and is found in the intima of arteries, a role for this element in ectopic calcification of valves may exist.

Role of brachytherapy in the management of pulmonary and mediastinal malignancies.

Brachytherapy, the permanent or temporary implantation of radioactive sources, has been performed in limited numbers of patients with lung cancer over the last 50 years. Because of renewed interest in this modality, we reviewed our experience with 103 patients treated over a 7-year period. The mean age of this group was 55.5 years (range, 1 to 84 years). Primary lung cancer accounted for 82 patients (79.6%); metastatic lesions to the lung, 13 (12.6%); and mediastinal malignancies, 8 (7.8%). Indications for brachytherapy included mediastinal and chest wall invasion in 42 patients (40.8%), unresectable tumors and mediastinal adenopathy in 30 (29.1%), medical contraindications to extensive pulmonary resection in 20 (19.4%), and irradiation of excised lymph node beds in 11 (10.7%). Seeds labeled with radioactive iodine 125 alone were used in 65 patients (63.1%), afterloading catheters containing iridium 192 sources in 25 (24.3%), and both in 13 (12.6%). There were no operative deaths. With a mean follow-up of 18.6 months, the mean and median survivals for the entire group were 17.3 and 14.0 months, respectively. The 1-year, 2-year, and 3-year survivals for the entire group were 67.9%, 38.7%, and 27.8%, respectively. In summary, brachytherapy offers a useful surgical approach in patients in whom unresectable pulmonary or mediastinal malignancies are found at the time of thoracotomy or in patients previously treated with other modalities for whom limited therapeutic alternatives exist.

Can computed tomography of the chest stage lung cancer? Yes and no.

To determine the accuracy of computed tomography (CT) of the chest in the staging of lung cancer, we studied 418 patients with primary pulmonary carcinoma between 1979 and 1986. Each had a preoperative scan performed before detailed operative staging. Each CT scan was analyzed for components of the current TNM staging system. Computed tomography sensitivity and specificity for mediastinal lymph node metastasis were 84.4% and 84.1%, with corresponding positive and negative predictive accuracies of 68.7% and 92.9%, respectively. When TNM stages were derived from CT scans, only 190 of 418 (45.4%) completely agreed with operative staging. An additional 53 of 418 (12.7%) predicted the correct stage, although components of the TNM system were incorrect. In 94 of 418 scans (22.5%) CT overestimated the stage, whereas in 81 (19.4%) CT downgraded the stage. Computed tomography suggested metastatic lesions in liver, lung, adrenal gland, bone, or abdominal lymph nodes in 40 of 373 scans (10.7%); only five of 40 (12.5%) had documented metastasis. In summary, CT of the chest cannot accurately stage primary lung carcinoma according to the TNM classification. Because the negative predictive accuracy for mediastinal lymph node metastasis remains high (92.9%), invasive staging can be deferred for definitive thoracotomy when no lymphadenopathy is evident on CT. The high negative predictive accuracy for scans of the chest and upper abdomen makes CT a useful tool for exclusion of metastatic disease.

Bioprosthetic valve replacement of aortic valve endocarditis: Detroit experience.

Bioprosthetic valve replacement for aortic valve endocarditis was reviewed in 98 patients, 39 nonaddicts and 59 addicts, from the Henry Ford Hospital in Detroit. Multivariate analysis was carried out, and the bioprosthetic valve is a reasonable valve replacement device for both native and prosthetic valve endocarditis.

The porcine bioprosthetic heart valve: experience at 15 years.

The porcine bioprosthetic valve has been in use at Henry Ford Hospital since 1971. In this review, 980 patients with 1,081 porcine bioprosthetic valves were examined from 1 month to 16.4 years after implantation with a 99% complete follow-up. Patient survival was 59% +/- 2.2% (+/- standard error of the mean) at 10 years and 38% +/- 4.0% at 15 years. Factors associated with decreased survival after hospital discharge were age greater than 35 years and New York Heart Association functional class IV. Freedom from thromboembolism was 92% +/- 1.2% at 10 years and 89% +/- 3.2% at 15 years. Freedom from endocarditis was 93% +/- 1.2% at 10 years and 92% +/- 1.3% at 15 years. Freedom from structural valve degeneration for all valves was 71% +/- 2.6% at 10 years and 31% +/- 5.6% at 15 years. Factors associated with increased risk of structural valve degeneration were age younger than 35 years, female sex, and preoperative cardiac index greater than 2 L/min/m2. Among a total of 172 patients undergoing removal of a degenerated valve, mortality was 12.5%, and significant risk factors for death at reoperation were emergency operation and functional class IV. Experience with the porcine bioprosthetic valve after 15 years suggests that its use be confined to older patients or patients with a contraindication of anticoagulation.

Scanning electron microscopy of surgically excised human mitral valves in patients over 45 years of age.

Leaflets were obtained from 23 diseased mitral valves of patients over 45 years of age removed at the time of prosthetic valve insertion and the topography was studied with scanning electron microscopy. The clinical diagnosis in all cases was probable rheumatic heart disease. Filiform processes (Lambl's excrescences) were seen on 15 of 23 (65%) of these leaflets. Some of these processes appeared to develop when either bundles of collagen or elastic fibers in the connective tissue framework of the cusp were broken. The freed portion of the fiber then served as a nidus for thrombus formation. The endothelium on the surface of the leaflets was consistently altered. Endothelial cells were changed in shape, had microvilli scattered over their exterior, showed discontinuous cell borders and were desquamated, either singly or in groups. Elements of the peripheral blood adhered to the exposed subendothelium. Erythrocytes were usually entrapped in fibrin networks. Single activated platelets and platelet aggregates adhered to the fibers of the exposed subendothelial connective tissue. Surface mineral deposits were composed of granular spherulites, which contained both calcium and phosphorous. This study extends our understanding of the architectural modifications that contribute to the continuing pathologic process of rheumatic mitral valve disease.

Prediction of post-cardiopulmonary bypass cardiac output.

The ability to predict cardiac output (CO) before termination of cardiopulmonary bypass (CPB) allows identification of potential complications once the patient is off bypass. We have previously demonstrated that CO early after CPB can be reliably predicted by a plot of venous oxygen saturation at various flow rates on CPB, based on in-line monitoring of venous oxygen saturation. In this study, we evaluated a simplified technique for predicting CO with a series of 50 patients on CPB. When CPB weaning began, patients were normothermic, anesthetized, and paralyzed. Venous oxygen saturation and arterial blood flow were recorded. At low pump flow just before termination of CPB, the final venous oxygen saturation was recorded. Assuming a proportional relationship between venous oxygen saturation and arterial blood flow, CO early after CPB was predicted. The simplified CO prediction was compared with the thermodilution CO immediately after CPB. The simplified technique reliably predicted CO early after CPB compared with the thermodilution technique. The simplicity and reliability increase the clinical value of the CO prediction.

Implantable electrical left ventricular assist system: bridge to transplantation and the future.

An implantable left ventricular assist system (LVAS) utilizing an electromechanically driven dual pusher-plate blood pump has been employed in a multiinstitutional trial as a bridge to cardiac transplantation. Under development for permanent circulatory support in patients with end-stage heart disease, the LVAS, in this application, derives power and control from an external console via a percutaneous lead. The LVAS was implanted in 20 patients (16 men, 4 women) who were hemodynamically unstable or in refractory cardiogenic shock. The mean age was 44.9 years (range, 25 to 63 years). Preoperative diagnosis was evenly divided between end-stage ischemic disease, cardiomyopathy, and acute myocardial infarction. Implanted in the left upper quadrant within the anterior abdominal wall, the blood pump was connected between the left ventricular apex and ascending aorta. Total support of the systemic circulation and substantial left ventricular unloading were achieved with synchronous counterpulsation for periods up to 90 days (mean, 22.7 days). All patients were stabilized hemodynamically. The mean preoperative cardiac index of 1.5 L/min/m2 increased by a factor of 2. Pulmonary arterial pressures decreased substantially. Serious complications occurred in 16 patients, precluding cardiac transplantation in 10. Most complications (greater than 70%) were in patients who did not receive transplants; the most common complication was bleeding. Twelve of 13 patients with LVAS implants for more than seven days were mobilized, and 4 were fully ambulatory and completely rehabilitated. Orthotopic cardiac transplantation was performed in 10 patients after implants ranging from two to 90 days (mean, 30.3 days).(ABSTRACT TRUNCATED AT 250 WORDS)

Minnesota ALG. Safe and effective immunosuppression for cardiac transplantation.

Fifty-six patients undergoing orthotopic cardiac transplantation were given Minnesota ALG prophylactically or therapeutically for acute cardiac rejection. During a follow-up period of 0-28 months (mean follow-up period, 11.9 months), the actuarial survival for the entire group was 96% and 86% at 30 days and 1 year, respectively. Actuarial freedom from rejection was 60% and 28% at 30 days and 1 year, respectively. All but seven rejection episodes responded to initial steroid pulses or a modification of a maintenance cyclosporine and azathioprine regimen. The seven failures were rescued with further Minnesota ALG therapy. Few serious hematologic or allergic reactions to Minnesota ALG were observed, and no new malignancies occurred during the follow-up period. We conclude that Minnesota ALG is safe and effective in cardiac transplantation.

Energy expenditure of autoperfusing heart-lung preparation.

The autoperfused heart-lung preparation was developed as a method for extending the acceptable donor-to-recipient interval in clinical heart-lung transplantation. Metabolic substrate enhancement has been shown to be necessary for the survival and homeostasis of the functioning preparation. To define basic metabolic requirements and to determine the resting energy expenditure of the working canine heart-lung preparation, two groups were studied. Ten canine heart-lung blocks were placed in a normothermic autoperfusion circuit. In Group 1 (n = 5), a hyperalimentation solution of balanced substrate was infused (15% dextrose, 4.25% amino acids, 8 meq magnesium sulfate, 30 IU/dl insulin, and 10% lipids). In Group 2 (n = 5), no substrate was given. The preparations were ventilated with a mixture of room air and 5% CO2 at a rate of 4 breaths/min to maintain physiological pH. Myocardial function was assessed by cardiac output determinations and mixed venous gases. Pulmonary function was assessed with arterial blood gases. The oxygen consumption (VO2) and carbon dioxide production (VCO2) were measured with a Metabolic Cart, and the resting energy expenditure was calculated. The mean survival time for Group 1 was 360 minutes, and all preparations were terminated electively. The mean survival time for Group 2 was 219 +/- 43 minutes (p less than 0.01) with congestive heart failure as the common terminal event. All parameters of cardiac function and blood gases remained within physiological limits without significant differences between groups. The resting energy expenditure, a measure of metabolic rate, was 2.5 +/- 0.3 kcal/hr in Group 1 and 1.0 +/- 0.2 in Group 2 at termination (mean +/- SD) (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

The future of bioprosthetic valves.

The glutaraldehyde treated bioprosthetic heart valve is the most intensively studied valve in the history of heart valve replacement. The valve is examined from three aspects: hemodynamics, thromboembolism, and durability. The hemodynamic performance of the porcine bioprosthetic heart valve reveals that it performs as well as the Hall-Medtronic valve, better than the Starr-Edwards valve, but not as well as the St. Jude valve. The main reason for using the bioprosthetic heart valve is to decrease thromboembolism or avoid anticoagulation. The author concludes that evidence appears to support that with bioprosthetic heart valves the incidence of thromboembolism is indistinguishable from the best mechanical heart valves, with the difference being that patients with bioprosthetic valves do not need to be anticoagulated. In our experience with durability at 15 years, freedom from primary tissue failure with the porcine bioprosthetic heart valve is 41% for all valves, 44.8% for the aortic valves, and 40.8% for the mitral valve. After 15 years experience with the porcine bioprosthetic heart valve its main limitation is its lack of durability and therefore currently is used for selected indications.

Leukocytes, platelets, and surface microstructure of spontaneously degenerated porcine bioprosthetic valves.

The microstructure of 33 spontaneously degenerated porcine bioprosthetic valves was assessed by scanning electron microscopy in order to gather insight regarding the degenerative process. Twenty-four mitral and 9 aortic valves were removed from 32 patients. The duration of insertion was 7.7 +/- 2.4 years (mean +/- SD). All valves showed denudation of endothelial cells and exposure of the subendothelial fibrous tissue. Fibroblastlike cells were occasionally seen. Platelet deposits were observed on 22 of 33 valves (67%). Leukocytes were observed on the surface of 27 of 33 valves (82%). Mononuclear leukocytes were the most common category of cells (66%). Crystalline material was present on the surface of some leukocytes, suggesting that they may serve as a nidus for calcification. Transmission electron microscopy showed leukocytes in the process of phagocytizing collagen fibers. Macrophages, by exerting their scavenger function seem to contribute to destruction of the collagen framework of the valves. Whether the observed lymphocytes and plasma cells reflect an immunological involvement is unclear.

Prevention of early postoperative renal dysfunction in cardiac transplantation.

Fifty six patients undergoing cardiac transplantation were immunosuppressed with a multi-drug induction regimen in which Cs administration was delayed postoperatively until satisfactory hemodynamics and renal function were achieved. The advantage of this approach is the absence of acute renal dysfunction in the early postoperative period. This immunosuppressive regimen was well tolerated and without significant detrimental effects on patient survival, graft rejection, or infection.

Infection surveillance in cardiac transplantation.

Infections are a major cause of morbidity and mortality in cardiac transplantation. There is little information describing screening and prospective surveillance of heart recipients. We describe a surveillance program that was used for 35 patients, which screens and follows recipients through serologic, virologic, and immunologic parameters. Pretransplantation surveillance identified four (11.4%) patients whose skin tests with purified protein derivative (PPD) were positive, one patient with giardiasis, and seven (20%) recipients who were susceptible to cytomegalovirus (CMV). Twelve (34.3%) patients had CMV infections, only one of which was primary and involved a seropositive donor. The low rate of primary infection (14%) may result from our use of CMV-negative blood products. Seven (20%) recipients who were seronegative for toxoplasmosis received seropositive hearts, and disseminated toxoplasmosis developed in one of them. Eight (22.8%) patients had asymptomatic significant increases in Epstein-Barr virus antibody titers, without evidence of lymphoma. Fifteen (42.8%) recipients had at least one herpes simplex virus reactivation. Preventive, diagnostic, and early therapeutic interventions should occur as a result of infection surveillance, thus leading to a reduced risk of infection during the period after cardiac transplantation.