Biomedical subjects

O H Frazier

Publications and source records attributed to O H Frazier.

At least 433 records · Page 24Linked to original sources

PubMedDate not supplied

Long-term results in diabetic patients undergoing heart transplantation.

We conducted a retrospective study of 305 nondiabetic patients and 37 diabetic patients who underwent heart transplantation from July 1982 to May 1990. Actuarial survival was similar for both groups of patients at 1 year (76.4% versus 81.3%) and at 2 years (69.6% versus 73.0%). Because we were interested in long-term results, we further analyzed only those patients surviving more than 1 year after transplantation (214 nondiabetic patients and 29 diabetic patients). Mean follow-up for the nondiabetic patients was 31.8 +/- 16.2 months and for the diabetic patients, 32.9 +/- 4.1 months. The respective mean age in each group was 50.4 +/- 10.3 years and 51.6 +/- 9.1 years. No difference was observed between the nondiabetic patients and diabetic patients regarding the rejection rate per patient-month (0.040 +/- 0.041 versus 0.045 +/- 0.051 episodes per patient-month), the infection rate per patient-month (0.056 +/- 0.081 versus 0.081 +/- 0.102 episodes per patient-month), or renal function as evidenced by mean creatinine levels at 1, 2, and 3 years. Twelve patients were insulin-dependent before transplantation; and 1 year after transplantation, they required an insulin dose 2.12 times greater than the dose before operation. Coronary artery disease developed in 32.8% of the nondiabetic patients, compared with 31.0% of the diabetic patients by the fourth year of follow-up. Despite the need for increased insulin doses, the diabetic patients had similar long-term survival to that of the nondiabetic patients, without an increased risk of rejection, infection, renal dysfunction, or coronary artery disease. Our experience supports the feasibility of heart transplantation in selected diabetic recipients.

Adult↗

PubMedDate not supplied

Heart transplantation after mechanical circulatory support: four years' experience.

To determine the effect of mechanical circulatory support before heart transplantation, we conducted a retrospective analysis of 207 men who underwent staged orthotopic transplantations. Of these patients, 185 (group I) required pharmacologic support before transplantation; 14 (group II) required mechanical circulatory support with an intraaortic balloon pump (duration of support, 1 to 26 days); and eight (group III) required advanced mechanical circulatory support with an implantable left ventricular assist device (duration of support, 19 to 132 days). A comparison of complications after transplantation (infection and rejection), hospitalization, and survival showed that no significant differences existed among the three groups. In each group, respectively, 1-year survival was 80.9%, 77.3%, and 75%, and 2-year survival was 75.7%, 67.7%, and 75%. Based on our experience, patients receiving mechanical circulatory support before transplantation can be expected to have a good outcome. In fact, such support can help to improve their end-organ perfusion, and, thus, their status as heart transplantation candidates. Furthermore, this study shows that advanced mechanical circulatory support is possible even for prolonged periods, with low risk of sudden death. This finding is an important step toward development of a permanent assist device.

Adult↗

PubMedDate not supplied

Successful bridge to heart transplantation with a new left ventricular assist device.

During the last 5 years, a new pneumatically driven left ventricular assist device has been implanted in 18 heart transplantation candidates who required advanced mechanical circulatory support. The mean duration of support was 80 +/- 74 days, and the cumulative support time was 1400 days. Fifteen patients were successfully supported until the time of heart transplantation. As a result of early experience, in which three of four patients died after heart transplantation because their end-organ function failed to recover, subsequent efforts were made to institute support early, before irreversible organ damage occurred. Eleven of the 12 patients in the later experience are currently alive and well at a mean follow-up of 12.6 +/- 7.5 months. No thromboembolic episodes occurred, and minimal anticoagulation was required. Furthermore, patients were able to participate in rehabilitative exercise programs, thus optimizing their transplantation status. Finally, the findings in these patients have shown the feasibility of providing long-term, or even permanent, cardiac assistance.

Adult↗

PubMedDate not supplied

Bacterial mediastinitis after heart transplantation.

Bacterial mediastinal abscess or mediastinitis developed in nine (2.5%) of 361 consecutive patients who underwent isolated heart transplantation at the Texas Heart Institute. All nine patients had at least one predisposing factor that may have contributed to the development of mediastinitis. These included insulin-dependent diabetes mellitus, repeat operation for postoperative mediastinal hemorrhage, Staphylococcus aureus pneumonitis, and cardiac allograft rejection in the early postoperative period (less than 30 days), necessitating steroid pulse therapy alone or in combination with murine-derived monoclonal antibody (OKT3). In six of the nine patients, the diagnosis of mediastinitis was made on the basis of clinical findings (unstable sternum and incisional erythema, with or without gross purulence), and in the other three patients, diagnosis was confirmed by computed tomography of the chest. Culture data were unequivocal in all patients; S. aureus was the most frequent (five patients), followed by S. epidermidis (two patients), and Enterobacter cloacae (two patients). Computed tomography-directed percutaneous drainage and systemic antibiotics were successful in treating two of three patients who had stable sternums with mediastinal abscess. In the remaining seven patients, sternal and mediastinal debridement with rewiring of the sternum was successfully applied. No patient required muscle or omental flap coverage, and no patient experienced a recurrence of mediastinitis during an average follow-up period of 35 months (range, 12 to 46 months).

Female↗

PubMedDate not supplied

Frequency and significance of infections in patients receiving prolonged LVAD support.

Infections in patients undergoing mechanical circulatory support as a bridge to transplant are associated with significant mortality and morbidity. To determine the frequency and effects of infection during such procedures, a retrospective analysis was done of 14 patients who received prolonged (greater than 14 days) support with the Heartmate left ventricular assist device (LVAD) (Thermo Cardiosystems, Inc., Woburn, MA). All patients were men (mean age, 44.3 years), and duration of LVAD support ranged from 19 to 233 days (mean, 98.1 days). During LVAD support, five patients had no infections, and, in the remaining nine patients, infections were most common in the respiratory tract, catheter tips, and urine. Four device related infections occurred in three patients, all of which were resolved with antibiotic therapy. All 14 patients underwent transplantations, and none of the operations was delayed because of infection. Eleven of the patients are long-term survivors (range of time after transplant, 7.5-37 months). Infections were not associated with mortality or significant morbidity in this group of patients.

Adult↗

PubMedDate not supplied

Quality of life in long-term survivors of the Hemopump left ventricular assist device.

The courses of 10 patients (nine men and one woman; mean age, 54 years) were reviewed to determine the long-term results of treatment with the Hemopump (Nimbus Medical, Inc., Rancho Cordova, CA) left ventricular assist device. Indications for treatment were postcardiotomy cardiogenic shock (n = 8) and acute cardiac allograft rejection (n = 2). Two of the patients with postcardiotomy shock required a bridge to transplantation. At follow-up (mean, 21 months), eight patients were alive: four were in New York Heart Association Functional Class I and four were in Class II. None had long-term adverse effects that were attributable to the site of insertion (e.g., limb ischemia or infected groin wounds). All the patients considered themselves independent in their daily activities, and most of the patients were able to exercise and pursue hobbies. The Hemopump appears to offer long-term survival with an acceptable quality of life to a population of patients whose survival would have been highly unlikely otherwise.

Activities of Daily Living↗

PubMedDate not supplied

Extended support with a left ventricular assist device as a bridge to heart transplantation.

The Heartmate-1000IP, an intracorporeal, pneumatically activated, pulsatile left ventricular assist device (LVAD) with textured blood-contacting surfaces, is undergoing clinical evaluation as a bridge to heart transplantation (HTx). During a 3 year period (January 1988 to April 1991), the authors evaluated 12 patients who required extended LVAD support (greater than 30 days) while awaiting HTx. Duration of support ranged from 31 to 233 days (mean, 117 days). LVAD performance was excellent, with average pump flow indices of 2.5-3.5 L/min/m2. Long-term antithrombotic therapy consisted of dipyridamole and aspirin in all except one patient who received only low-molecular-weight dextran. After the initial recovery period, prothrombin and partial thromboplastin times returned to baseline levels. Plasma-free hemoglobin levels averaged less than 10 mg/dl. One patient is currently receiving support (91+ days); the 11 other patients underwent successful HTx, with follow-up ranging from 7 to 36 months. The authors' cumulative experience with this LVAD totals more than 1,506 days of support (greater than 4 years) without evidence of any thromboembolic episodes. These results suggest that this LVAD provides an effective bridge to HTx for extended periods.

Adult↗

PubMedDate not supplied

Adjuvant native heart surgery during heterotopic heart transplantation: two case reports.

The results of heterotopic heart transplantation may be further improved if repairs on native heart abnormalities are performed just before implantation of the allograft. Such procedures increase the potential for the recipient's own heart to recover function and, thus, to maintain circulation if the heterotopic heart malfunctions or fails. The native hearts of two of our patients, both women, showed signs of greater contractility and ejection after repair and were able to provide adequate circulatory support during periods of donor heart failure. The first patient required ventricular aneurysmectomy and coronary artery bypass grafting, and the second, native mitral valve repair. Moreover, when persistent ventricular fibrillation occurred in the donor heart of the first patient, a donor cardiectomy was performed, and the recipient heart functioned well thereafter. As more adjuvant operations are performed and the results evaluated, we may find that heterotopic operations would be suitable in a greater variety of heart transplant candidates.

Coronary Artery Bypass↗

PubMedDate not supplied

Coronary artery bypass two years after orthotopic heart transplantation: a case report.

Complete occlusion of the left anterior descending and right coronary arteries developed in a 58-year-old man 2 years after orthotopic heart transplantation. Because of his progressive shortness of breath, reversible myocardial ischemia, and decreasing ejection fraction, aortocoronary bypass was recommended. The operation was performed without complications, and his postoperative ejection fraction improved by more than 58%. In the past, when coronary artery disease developed in cardiac allografts, another transplant procedure was the only treatment option. Because of the limited donor hearts available today, new strategies are necessary for the treatment of cardiac allograft atherosclerosis.

Coronary Artery Bypass↗

PubMedDate not supplied

Impact of long-term cyclosporine immunosuppressive therapy on native kidneys versus renal allografts: serial renal function in heart and kidney transplant recipients.

Aggregate analyses of the impact of long-term cyclosporine administration in kidney transplant recipients have reported generally impaired but stable allograft function. In contrast, experience in extrarenal transplantation has suggested that treatment with cyclosporine for periods in excess of 12 months causes a progressive native nephropathy often leading to dialysis dependence. The extent of this apparent discrepancy between native kidneys and renal allografts is the subject of this study, which examines the evolution of renal function in 119 kidney and 100 heart transplant recipients receiving 12 or more months of cyclosporine immunosuppressive therapy administered in uniform protocols by affiliated clinical transplantation programs. The evolution of renal function in both study cohorts was analyzed retrospectively on the basis of serial serum creatinine (Crs) determinations. Assessment of group mean Crs, reciprocal Crs (1/Crs), and slopes of the curves obtained by plotting 1/Crs versus time in individual patients revealed a significant decline of native kidney function over the first 6 posttransplant months in the cardiac allograft group. Thereafter, however, native kidney function stabilized in these patients, and the aggregate trend was suggestive of no further decline in function over a 3- to 4-year follow-up period. Kidney transplant recipients had an aggregate trend of slowly declining allograft function consistent with the effects of chronic immunologic injury. The data were not consistent with a uniform pattern of a progressive, cyclosporine-induced loss of renal function in either cohort. Long-term use of cyclosporine was found to be associated with impaired but generally stable aggregate renal function in both the heart and the kidney transplant cohorts.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMedDate not supplied

Treating cardiac allograft rejection: present approach--analysis of 100 consecutive patients.

In addition to rejection, complications of rejection prophylaxis and treatment are major causes of mortality and morbidity during the first year after heart transplantation. To decrease complications related to antirejection treatment, our present approach is to assess each rejection episode individually and to adjust treatment accordingly. This article presents the analysis of rejection in the last 100 patients who underwent heart transplantation at our institution.

Antibodies, Monoclonal↗

PubMedDate not supplied

Nutritional assessment of patients with extended left ventricular assist device support.

The nutritional status of nine patients with end-stage heart disease who were supported by a left ventricular assist device (LVAD) for more than 30 days while awaiting cardiac transplantation was evaluated. Nutritional status was indicated by the following scale: 0-2, adequate nourishment; 3-5, moderate malnourishment; greater than 5, severe malnourishment. This scale was based on serial assessments of albumin, transferrin, total lymphocyte count, percentage of ideal body weight, midarm circumference, triceps skinfold, and arm muscle circumference. Each variable was compared with established standards before implantation and before transplantation times and assessed 1 point if less than the normal value and 0 points if within the normal range. At the time of LVAD implantation, 5 patients had a score of 0-2, 3 patients had a score of 3-5, and 1 patient had a score greater than 5. At the time of cardiac transplantation, 7 patients had a score of 0-2, 2 patients had a score of 3-5, and no patients had a score greater than 5. The patients who were able to meet at least 50% of their daily caloric and protein requirements by oral intake alone were noted. At LVAD implantation, only 2 patients (22%) met this requirement; however, 6 patients (67%) met this requirement at the time of cardiac transplantation. All 9 patients underwent cardiac transplantation, and 8 survived. Thus, it appears that extended LVAD support and maintenance of hemodynamic stability allow patients to regain the desire and ability to achieve adequate nutritional status, which may considerably reduce their perioperative transplant risks.

Anthropometry↗

PubMedDate not supplied

Improved survival after Hemopump insertion in patients experiencing postcardiotomy cardiogenic shock during cardiopulmonary bypass.

Immediate placement of a Hemopump (HP) ventricular assist device was undertaken in nine patients (seven men, two women) after other attempts at weaning from cardiopulmonary bypass (CPB) after coronary bypass surgery had failed. All nine patients (100%) were successfully weaned from CPB, and six (63.3%) gradually improved enough to permit removal of HP support. Five (83.3%) of the six who were weaned from CPB survived beyond hospital discharge. HP support was evaluated in terms of vital organ function, incidence of complications, and clinical outcome. In both survivors (S) and nonsurvivors (NS), serial hemodynamic measurements were taken. Although there were few differences in hemodynamic parameters between groups at 4 hr, by 24 hr the S group had markedly improved cardiac index, Glasgow Coma Scale, urinary output, and pulse pressure and required far less inotropic support than did the NS group. All four patients who required high dose inotropic agents to maintain acceptable end-organ perfusion on HP support died; three were unable to tolerate weaning from the HP, and all died within 72 hr of surgery because of ineffective myocardial recovery. None of the survivors required additional early inotropic augmentation. Renal perfusion appeared to be well maintained, even with mean arterial pressures below 60 mmHg during HP support. There were no episodes of hemolysis, infection, or limb ischemia in either group. Thus, the Hemopump provided excellent circulatory support for those patients who could not be weaned from CPB by traditional methods.

Cardiopulmonary Bypass↗

PubMedDate not supplied

Treatment of cardiac allograft failure by use of an intraaortic axial flow pump.

Since April 1988 we have used the Hemopump device, a new means of circulatory support, to successfully treat three orthotopic heart transplant recipients with biventricular failure refractory to conventional therapy. The Hemopump device is a 21F catheter-mounted, transvalvular, intraaortic axial flow pump. Power to the pump is percutaneously transmitted from an external electromechanical drive console by a flexible drive cable. We first used the pump in a 61-year-old man in whom severe steroid-resistant rejection developed 28 days after heart transplant, resulting in cardiogenic shock (cardiac index less than 2.0 L/min/m2) despite maximal inotropic support. In the second case a 49-year-old man with no evidence of pulmonary hypertension sustained cardiac arrest 2 hours after heart transplant, necessitating open chest massage and emergency cardiopulmonary bypass. The third patient was a 9-year-old boy in whom rejection developed 5 months after heart transplant, resulting in congestive heart failure that was unresponsive to maximal medical therapy. The device was implanted by way of the femoral artery approach in the first case, the ascending aorta in the second, and the distal abdominal aorta in the third. Duration of support was 46 hours, 65 hours, and 6 days, respectively. Increased blood flow provided by the pump ranged from 2 to 4 L/min. No device-related complications, such as hemolysis, infection, or thromboembolic events, occurred. All patients recovered normal heart function and were weaned from the device. The first patient is well after 12 months. The second patient died of metastatic lymphoma at 2 months, and the third died of Pseudomonas pneumonia after 2 weeks.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗

PubMedDate not supplied

Clinical experience with Muromonab-CD3 monoclonal antibody (OKT3) in heart transplantation.

Muromonab-CD3 (Orthoclone OKT3) monoclonal antibody was used as immunosuppressive therapy in 24 selected, cyclosporine-treated heart transplant recipients. Patients included 15 men, eight women, and one child. Mean age was 47 years. Eight patients (group 1) received OKT3 as rescue therapy for rejection, eight (group 2) as primary therapy for rejection, and eight (group 3) as induction therapy. Drug efficacy in the reversal or prevention of rejection in group 1 was 71%; in groups 2 and 3 it was 100%. Recurrent rejection occurred in three of 20 (15%) patients, despite optimal cyclosporine maintenance therapy after OKT3 therapy. Two patients were re-treated successfully for rejection with second courses of OKT3. Systemic side effects occurred in all patients, but in no case did they necessitate cessation of therapy. Infectious complications occurred in all except one patient, typically within the first month after therapy. On the basis of this experience, OKT3 therapy appears highly effective in reversing and preventing cardiac allograft rejection. Further research of the potential complications of such therapy is required to establish optimal dosing schedules and indications for its use after heart transplantation.

Antibodies, Monoclonal↗

PubMedDate not supplied

Selective use of OKT3 in heart transplantation with the use of risk factor analysis.

Heart transplant patients who develop early (within 2 weeks after transplantation) severe renal dysfunction require an alternative to cyclosporine-based immunosuppressive induction therapy. In our experience, muromonab-CD3 (Orthoclone OKT3) is an excellent alternative for such patients. When compared with cyclosporine, however, it is associated with a higher incidence of infection. We conducted a retrospective analysis of a series of our patients to improve our ability to identify such patients. Selected risk factors for severe renal dysfunction included creatinine clearance less than 55 ml/min, hospitalization before transplant, perioperative cardiovascular compromise, and mechanical circulatory support. Of 50 adult patients (mean age 52 years), 35 (70%) completed full induction with intravenous (IV) cyclosporine (1 to 4 mg/kg/24 hr); 13 (26%) developed severe renal dysfunction; and two (4%) were excluded as a result of nonprotocol failures. Of the 13 patients in whom IV cyclosporine induction was precluded by severe renal dysfunction, 11 (85%) received IV OKT3 (5 mg/24 hr), and two (15%) received antithymocyte globulin (14 mg/kg/24 hr). Chi-square analysis showed perioperative cardiovascular compromise (p less than 0.001), hospitalization before transplant (p less than 0.001), and low creatinine clearance level (p less than 0.01) to be significantly associated with the development of severe renal dysfunction. The incidence of infection among patients treated with only IV cyclosporine versus OKT3 was 0.7 and 2.3 episodes per patient, respectively. This experience suggests that the selective use of OKT3 and IV cyclosporine with the use of risk factor analysis may improve individualization of induction therapy in heart transplant patients.

Adult↗

PubMedDate not supplied

Predictors of severe renal dysfunction after heart transplantation and intravenous cyclosporine therapy.

We conducted a retrospective analysis of 23 consecutive adult heart transplant patients treated with intravenous cyclosporine for induction of immunosuppression to determine predictors of early (within 2 weeks of transplantation) severe renal dysfunction. Selected risk factors included creatinine clearance less than 55 ml/min, hospitalization before transplantation, perioperative cardiovascular compromise, postoperative cardiovascular compromise, use of ranitidine, use of captopril, and preoperative intraaortic balloon pump support. Each risk factor was assigned a score of 1. Of 23 patients, 16 (69.7%, group 1) completed a course of intravenous cyclosporine for induction of immunosuppression, whereas seven (30.4%, group 2) developed severe renal dysfunction, precluding the use of intravenous cyclosporine for induction. Chi-square analysis showed hospitalization (p less than 0.001), creatinine clearance (P less than 0.001), perioperative cardiovascular compromise (p less than 0.05), and intraaortic balloon pump support (p less than 0.05) to be significantly associated with severe renal dysfunction. Of the patients with a risk factor score of 2 or greater, 87% developed severe renal dysfunction, and 100% with a score less than 2 did not. The best predictors of severe renal dysfunction were, in order, hospitalization, creatinine clearance, and perioperative cardiovascular compromise. Modification of the risk factor score with only these factors showed a score of 2 or greater predictive of severe renal dysfunction in 100% of patients; of those patients with a score less than 2, 94% did not develop severe renal dysfunction. This early experience suggests that risk factor analysis may be useful in the selection of patients in whom intravenous cyclosporine may be given with minimal risk for developing severe renal dysfunction.

Acute Kidney Injury↗

PubMedDate not supplied

Effect of ABO blood type on survival of heart transplant patients treated with cyclosporine.

We conducted a retrospective analysis of how ABO blood type matching affects the survival rate of heart transplant recipients. The study included 189 patients treated with cyclosporine who had heart transplantations at the Texas Heart Institute, Houston, between July 1982 and June 1987. There were 78 patients with blood type A, 28 with type B, five with type AB, and 78 with type O. Therefore, 33 patients had B antigen (types B and AB), and 156 lacked B antigen (types A and O). Of the 189 patients, 152 received ABO identical hearts and 37 received ABO nonidentical hearts from donors with compatible blood types. The 1-year graft survival for patients with B antigen was 66.7% compared with 78.1% for those without B antigen (p less than 0.05). More patients in the B antigen group, however, had transplantations with ABO nonidentical hearts. Patients with type O blood had the best 1-year survival (80.7%). Recipients of ABO identical donor hearts had a better graft survival than those with ABO nonidentical donor hearts: for type A patients, survival was 78.5% and 64.7%, respectively; for type B patients, survival was 75.0% and 62.5%, respectively. The 1-year survival was better for the patients with ABO identical hearts (79.5%) than for those with ABO nonidentical hearts (62.2%, p less than 0.01). The incidence of fatal rejection in ABO nonidentical hearts was higher than in ABO identical hearts (13.5% versus 2.6%, p less than 0.05). Over the last 6 years we have used various criteria for recipient and donor selection and for determining which immunosuppressive regimens are most effective. From this series of patients we believe that ABO identical matching of heart transplant recipients and donors improves the long-term survival rate.

ABO Blood-Group System↗