RESUMEN
The mechanisms by which the denervated heart responds to supine exercise were assessed by equilibrium gated radionuclide angiography in 18 cardiac transplant recipients 1 to 25 months (mean 11) after surgery. Results were compared with those in 15 normal subjects. Exercise duration among transplant recipients did not differ significantly from that in normal subjects. The heart rate at rest in transplant patients was 30% higher than in normal volunteers. Heart rate increased only 3% between rest and the first stage of exercise in transplant recipients compared with a 37% increase in the normal group (p less than 0.001). Cardiac output at rest was similar in both groups although the rate of rise of cardiac output and peak cardiac output were significantly lower among the transplant recipients. In early exercise, the means by which cardiac output increased in the transplant patients differed significantly from normal. In the transplant recipients, the left ventricular end-diastolic volume index increased 14% compared with a decrease of 2% in normal subjects (p less than 0.001) during the first stage of exercise. At the same time, the end-systolic volume index increased 6% in the transplant group but decreased 11% in normal subjects (p less than 0.001). These changes resulted in an overall increase in stroke volume by 20% in the transplant group compared with only a slight increase (+3%) in normal subjects (p less than 0.001) during the first stage of exercise. Among transplant recipients, the stroke volume index plateaued after the first stage of exercise, which, in combination with the blunted chronotropic response, resulted in a peak cardiac index 25% lower than that in normal subjects (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Prueba de Esfuerzo , Trasplante de Corazón , Hemodinámica , Adolescente , Adulto , Gasto Cardíaco , Ciclosporinas/uso terapéutico , Femenino , Corazón/diagnóstico por imagen , Corazón/fisiología , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana Edad , Postura , Angiografía por Radionúclidos , Volumen SistólicoRESUMEN
To characterize the spectrum of hemodynamic findings after orthotopic cardiac transplantation, 20 healthy heart transplant recipients with no evidence of cardiac dysfunction by noninvasive testing were studied for 1 to 51 months (mean 15) following surgery. After routine endomyocardial biopsy, right-sided heart pressures and thermodilution cardiac outputs were measured at rest (supine) and during symptom-limited, graded supine exercise. In addition, the effect of respiration on right atrial pressures and waveforms was determined at rest (supine, legs down), and after passive leg raising (volume loading). During exercise, striking increases of pulmonary artery, pulmonary artery wedge and right atrial pressures were seen. The mean pulmonary artery pressure rose 45% during the first stage of exercise (p less than 0.001) and by peak exercise it had increased 87% above resting values. The pulmonary artery wedge pressure increased significantly with passive leg elevation (p less than 0.001) and during the first stage of exercise rose 61% above baseline values. By peak exercise the mean pulmonary artery wedge pressure was more than double the resting value. Similarly, the right atrial mean pressure increased significantly (p less than 0.001) with passive leg elevation and nearly tripled at peak exercise. All values promptly returned to near baseline after exercise. The cardiac output increased 98% during exercise. During early exercise, the rise in cardiac output was mediated primarily by an increase in stroke volume. At rest, there was an abnormal response in right atrial mean pressure during slow deep inspiration in 7 individuals with legs down and in 12 after passive leg elevation (volume loading), including 4 of 10 patients studied beyond 1 year.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Trasplante de Corazón , Hemodinámica , Esfuerzo Físico , Adolescente , Adulto , Angiografía Coronaria , Ecocardiografía , Prueba de Esfuerzo , Femenino , Corazón/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Descanso , Supinación , Factores de TiempoRESUMEN
To assess the diagnostic applicability of magnetic resonance imaging (MRI) for diagnosis of cardiac allograft rejection, 25 patients who recently underwent cardiac transplantation were studied on a 0.15-tesla resistive system within 24 hours of endomyocardial biopsy. Ten normal volunteers and 4 patients who had recent (within 2 weeks) nontransplant cardiac surgery were also studied. In the 19 transplant patients imaged within 24 days of graft implantation, only 1 had evidence of graft rejection on biopsy. However, all nonrejecting grafts had increased T1 and T2 values, 501 +/- 22 and 61 +/- 6 ms, respectively (mean +/- standard deviation) and the only rejecting graft had values of 496 and 60 ms, respectively. In the normal volunteers mean T1 was 352 +/- 18 ms and T2 was 35 +/- 6 ms. There was no significant difference in T1 and T2 values between patients who underwent nontransplant surgery and control subjects. In patients with nonrejecting transplants who were imaged more than 25 days after surgery, the T1 and T2 values had normalized to 359 +/- 17 ms and 36 +/- 7 ms, respectively (n = 28 images in 20 patients). However, in those grafts with rejection, T1 and T2 were both elevated to 502 +/- 21 ms and 62 +/- 6 ms, respectively (n = 15 in 13 patients); wall thickness was also increased. Fourteen of 15 late rejection events (more than 25 days after surgery) were correctly identified on the basis of increases in T1 and T2 to more than 2 standard deviations above normal.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Rechazo de Injerto , Trasplante de Corazón , Espectroscopía de Resonancia Magnética , Adolescente , Adulto , Femenino , Humanos , Terapia de Inmunosupresión , Masculino , Persona de Mediana Edad , Monitoreo FisiológicoRESUMEN
To determine the prevalence, time course and factors responsible for hyperlipidemia after heart transplantation, 83 consecutive 1-year survivors were studied. By 1 year, 83% of patients had serum total cholesterol levels greater than 5.2 mmol/liter (200 mg/dl) and 28% of the patients had serum total cholesterol higher than the age- and sex-matched ninety-fifth percentile. At the end of 1-year follow-up, serum total cholesterol correlated with the recipient age (p less than 0.0001), the preoperative cholesterol level (p less than 0.001), the actual dose of maintenance prednisone at 1 year (p less than 0.02) and the cumulative 1-year steroid dose (p less than 0.03). Similarly, the serum triglyceride level at 1 year correlated with the pretransplant level of serum triglycerides (p less than 0.0001), recipient age (p less than 0.03) and cumulative 1-year steroid dose (p less than 0.03). Patients with a pretransplant diagnosis of coronary artery disease had a significantly higher level of serum total cholesterol and triglyceride levels at 1 year (p less than 0.02 and p less than 0.03, respectively). Heart transplant recipients with body mass index greater than or equal to 25 kg/m2 also presented with significantly elevated serum total cholesterol and triglyceride levels at 1 year compared with nonobese patients (p less than 0.01 and p less than 0.002, respectively). Hyperlipidemia occurs frequently and is detected within the first month after heart transplantation. Optimal management of this problem requires further study.
Asunto(s)
Trasplante de Corazón/fisiología , Lípidos/sangre , Adolescente , Adulto , Peso Corporal , Niño , Femenino , Trasplante de Corazón/efectos adversos , Humanos , Hiperlipidemias/etiología , Inmunosupresores/administración & dosificación , Masculino , Persona de Mediana Edad , Factores de Riesgo , Factores de Tiempo , Triglicéridos/sangreRESUMEN
Although anatomic reinnervation of the donor heart is unlikely after transplantation, individual subjects have been noted to show near physiologic heart rate (HR) responses to exercise. To assess development of this phenomenon, we studied HR changes in response to orthostasis and treadmill exercise in 52 orthotopic cardiac transplant recipients grouped according to time after transplantation. In group 1 (2.0 +/- 0.9 months), no significant increase in HR was seen up to 100 cardiac cycles after standing. A maximal acceleration of 4.0 +/- 3.8 beats was seen within 100 cardiac cycles after standing in group 2 (15.8 +/- 5.6 months). Patients in group 3 (42.4 +/- 12.4 months) showed significant cardioacceleration by 5 cardiac cycles after standing to a maximum of 10.7 +/- 5.8 beats/min within the first 100 cardiac cycles. During exercise, HR increased more rapidly during the first minute in group 3 compared with group 1 (p less than 0.01). After exercise, HR continued to increase in group 1 but decreased rapidly in the other groups, most notably group 3 (-26.5 +/- 16.5 by 2 minutes, p less than 0.0001 vs groups 1 and 2). These data indicate development of functional reinnervation after orthotopic heart transplantation. The phenomenon of early acceleration of the HR after orthostasis and rapid deceleration after exercise in transplant recipients implies a local cardiac mechanism rather than response to circulating catecholamines.
Asunto(s)
Frecuencia Cardíaca , Trasplante de Corazón , Adolescente , Adulto , Anciano , Niño , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Postura , PronaciónRESUMEN
The reported high incidence of coronary atherosclerosis in many transplant series led us to critically review our experience in 83 patients who have had selective coronary angiography at greater than or equal to 1 years after transplantation. Angiograms were reviewed for evidence of coronary vascular disease, and quantitative analysis of multiple coronary artery segments was performed in serial films. Qualitative analysis revealed only 3 of 83 patients with any angiographic abnormality at follow-up, 1 with minimal luminal irregularities in the right coronary artery at 1 year, a second with a 50% diameter stenosis of the proximal left anterior descending artery and minimal irregularity of the proximal circumflex artery at 1 year and a third patient who developed a new 30% diameter eccentric proximal right coronary artery stenosis at 3-year follow-up. The cumulative incidence of graft vascular disease assessed angiographically was therefore 2% at 1 year and 4% at 3 years. Quantitative analysis, however, showed a significant decrease in coronary artery luminal diameter over time. The mean left main coronary artery diameter decreased from 5.4 +/- 0.9 mm at 1 year to 4.7 +/- 0.8 mm at 3 years (p = 0.0007).(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Angiografía Coronaria , Enfermedad Coronaria/diagnóstico por imagen , Trasplante de Corazón , Complicaciones Posoperatorias/diagnóstico por imagen , Presión Sanguínea , Creatinina/sangre , Estudios de Seguimiento , Rechazo de Injerto/efectos de los fármacos , Humanos , Terapia de Inmunosupresión , Inhibidores de Agregación Plaquetaria/administración & dosificación , Triglicéridos/sangreRESUMEN
The mechanisms of improved functional capacity over the first year after cardiac transplantation are not well studied. To assess the contribution of cardiac changes to this improvement, the serial evolution of upright rest and exercise hemodynamics during graded upright bicycle exercise was studied in 17 patients at 3 and 12 months after heart transplantation. Heart rate responsiveness, reflected by rapid heart rate acceleration on sitting and rapid deceleration after exercise, developed in the first year. Pulmonary capillary wedge pressure was lower at 1 year, both at rest and at peak exercise (10 +/- 3 vs 13 +/- 5 mm Hg at rest supine and 14 +/- 6 vs 18 +/- 8 mm Hg at peak exercise, p less than 0.05). Similarly, right atrial pressures were also significantly lower at 1 year (4 +/- 2 vs 6 +/- 3 mm Hg at rest supine and 6 +/- 5 vs 11 +/- 5 mm Hg at peak exercise, p less than 0.05). Cardiac index at peak exercise was greater at 12 months (6.4 +/- 1.3 vs 5.8 +/- 0.8 liters/min/m2, p less than 0.05), mediated primarily by higher exercise heart rate (135 +/- 16 vs 125 +/- 12 beats/min, p less than 0.05). In the first year after heart transplantation, improved rest and exercise hemodynamics and heart rate responsiveness contribute significantly to the improved functional capacity observed in these patients.
Asunto(s)
Ejercicio Físico/fisiología , Trasplante de Corazón/fisiología , Hemodinámica/fisiología , Adulto , Presión Sanguínea/fisiología , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Persona de Mediana Edad , Postura , Volumen Sistólico/fisiología , Factores de Tiempo , Resistencia Vascular/fisiologíaRESUMEN
Rupture of the left ventricle in the atrioventricular (AV) groove is a rare and usually fatal complication of mitral valve replacement (MVR). The successful repair of a delayed type I left ventricular rupture is described. The technique of repair is described, the literature reviewed, and three further cases from the authors' experience are reported.
Asunto(s)
Rotura Cardíaca/cirugía , Prótesis Valvulares Cardíacas/efectos adversos , Calcinosis/complicaciones , Femenino , Rotura Cardíaca/clasificación , Rotura Cardíaca/etiología , Prótesis Valvulares Cardíacas/clasificación , Ventrículos Cardíacos , Humanos , Persona de Mediana Edad , Válvula Mitral , Estenosis de la Válvula Mitral/complicaciones , Estenosis de la Válvula Mitral/cirugíaRESUMEN
Reactive hyperemia responses (RHR) of various magnitudes were obtained after release of a brief occlusion in six of 10 coronary bypass grafts. All of the vein grafts responded to an injection of sodium nitroprusside (50 microgram) directly into the open graft with an increase in blood flow that was always greater than the flow recorded after release of the occlusion. This response indicates that there were no flow-limiting stenoses and that the distal vascular beds were responsive to vasodilator stimuli. RHR's, expressed as percent repayment of calculated flow debt, were correlated significantly (r = 0.96, p less than 0.01) with the magnitude of the decrease in vein graft pressure measured during occlusion of the graft. It is suggested that the decrease in pressure is related to the amount of blood flow from alternate sources to the vascular bed during occlusion of the graft, and that this collateral flow is an important determinant of the magnitude of RHR in bypass grafts.
Asunto(s)
Circulación Colateral , Puente de Arteria Coronaria , Circulación Coronaria , Venas/trasplante , Administración Tópica , Velocidad del Flujo Sanguíneo , Determinación de la Presión Sanguínea , Circulación Colateral/efectos de los fármacos , Circulación Coronaria/efectos de los fármacos , Diástole , Humanos , Inyecciones Intravenosas , Métodos , Nitroprusiato/administración & dosificación , Nitroprusiato/farmacología , Vena Safena , Trasplante Autólogo , Vasodilatación/efectos de los fármacos , Venas/efectos de los fármacosRESUMEN
To reduce perioperative hemorrhage following heart-lung transplantation, several technical modifications were introduced in June 1988 to secure better posterior mediastinal hemostasis. The intraoperative and postoperative use of blood and blood products, as well as the chest tube drainage in the first 24 hours postoperatively, were compared in the seven patients operated on since June 1988 with the nine patients operated on before that date. Significant (p less than 0.05) reductions were demonstrated in the intraoperative and postoperative transfusion of packed cells, in the postoperative administration of fresh frozen plasma, and in the chest tube drainage within the first 24 hours postoperatively. The one-month and total hospital mortality rates were 6 percent and 12.5 percent, respectively. It is concluded that newer techniques to obtain optimal posterior mediastinal hemostasis have significantly reduced blood loss following heart-lung transplantation in our experience and have contributed to our excellent early postoperative results.
Asunto(s)
Trasplante de Corazón , Hemostasis Quirúrgica/métodos , Trasplante de Pulmón , Adolescente , Adulto , Pérdida de Sangre Quirúrgica , Transfusión Sanguínea , Niño , Drenaje , Femenino , Humanos , Masculino , Mediastino/cirugía , Persona de Mediana Edad , ReoperaciónRESUMEN
BACKGROUND: Patients with heart disease are frequently maintained on a regimen of aspirin because of its ability to decrease thrombotic complications and reduce the prevalence of unstable angina and myocardial infarction. Aspirin-induced platelet acetylation also increases bleeding caused by impairment of platelet function during cardiac surgery. METHODS: Between October 1990 and November 1991 this double-blind, randomized, placebo-controlled, parallel group interventional study examined the efficacy of high-dose aprotinin administration (up to 7 million KIU) to decrease blood loss and transfusion requirements in patients receiving aspirin within 48 hours of undergoing coronary bypass or valvular heart operations. Primary outcome measures in this study were total volume of blood loss (intraoperative blood loss plus postoperative chest tube drainage) and volume of transfusion during hospitalization. RESULTS: Patients treated with aprotinin (n = 29) had significantly lower total blood loss (1409 +/- 232 ml versus 2765 +/- 248 ml; p = 0.0002), intraoperative blood loss (503 +/- 53 ml versus 1055 +/- 199 ml; p = 0.0001), postoperative blood loss (906 +/- 204 ml versus 1710 +/- 202 ml; p = 0.0074), and prevalence of transfusion (59% versus 88% of patients; p = 0.016) than the placebo group (n = 25). The prevalence of complications including myocardial infarction was similar in the two groups. CONCLUSIONS: High-dose aprotinin significantly reduces blood loss and red blood cell transfusions in patients receiving aspirin who undergo cardiac operations.
Asunto(s)
Aprotinina/uso terapéutico , Aspirina/uso terapéutico , Pérdida de Sangre Quirúrgica/prevención & control , Procedimientos Quirúrgicos Cardíacos , Hemostasis Quirúrgica/métodos , Anciano , Transfusión Sanguínea , Volumen Sanguíneo , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio , Complicaciones PosoperatoriasRESUMEN
The results of heart-lung transplantation are improving with increasing experience in postoperative management, but obliterative bronchiolitis may still develop late postoperatively. We have performed 19 heart-lung transplants, with 1-month, 1-year, and 2-year actuarial survival rates of 95% +/- 5%, 84% +/- 8%, and 69% +/- 16%, respectively. Three early recipients died of bronchiolitis, and four patients who were operated on more than 2 years ago are currently being followed up with bronchiolitis. Since August 1988, 13 surviving recipients have undergone serial postoperative bronchoscopies and transbronchial biopsies with topical analgesia. Diffuse bronchomalacia, involving the main bronchi down to the fifth-order bronchi bilaterally, has developed in four patients with bronchiolitis 9 +/- 2 months after the diagnosis of bronchiolitis was confirmed. Pulmonary function tests have revealed a lower ratio of forced expiratory volume in 1 second to forced vital capacity, lower specific airway conductance, and higher airway resistance in heart-lung recipients with bronchomalacia than in patients with bronchiolitis alone. We conclude that diffuse bronchomalacia occurs frequently in heart-lung transplant recipients who have obliterative bronchiolitis. Bronchomalacia worsens the functional airflow obstruction caused by bronchiolitis and may play an important role clinically in the declining respiratory status of heart-lung transplant recipients.
Asunto(s)
Enfermedades Bronquiales/etiología , Trasplante de Corazón-Pulmón/efectos adversos , Adolescente , Adulto , Biopsia con Aguja , Bronquios/patología , Enfermedades Bronquiales/patología , Enfermedades Bronquiales/fisiopatología , Bronquiolitis Obliterante/etiología , Bronquiolitis Obliterante/patología , Bronquiolitis Obliterante/fisiopatología , Broncoscopía , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mecánica Respiratoria , EspirometríaRESUMEN
An international series of pulmonary retransplantation was updated to identify the predictors of survival in the intermediate-term after reoperation for obliterative bronchiolitis. The study cohort included 32 patients with end-stage obliterative bronchiolitis who underwent retransplantation in 15 North American and European centers between 1988 and 1992. Five types of retransplantation procedures were done, including repeat ipsilateral single lung transplantation (7 patients), repeat contralateral single lung transplantation (8 patients), repeat double lung transplantation (3 patients), double lung transplantation after a previous single lung transplantation (3 patients), and single lung transplantation after a previous double lung or heart-lung transplantation (11 patients). The mean interval between transplants was 564 +/- 51 days (range 187 to 1589 days). Postoperative follow-up was 100% complete and the average follow-up in surviving patients was 678 +/- 63 days. Actuarial survival was 72%, 53%, 50%, 41%, and 33% at 1, 3, 6, 12, and 24 months, respectively. Survival did not differ according to the age, preoperative diagnosis, ambulatory or ventilator status, or cytomegalovirus serologic status of the recipient before reoperation. Life-table and Cox proportional hazards analysis identified the type of retransplantation procedure and the year of reoperation as significant (p < 0.05) predictors of postoperative survival. Actuarial survival was significantly better in patients without an old, retained contralateral graft after retransplantation and in patients who underwent reoperation between 1990 and 1992, as opposed to between 1988 and 1989. Infection was the most common cause of death at all time intervals after retransplantation, although all deaths beyond 2 years resulted from obliterative bronchiolitis of the second graft. Most surviving patients are in a satisfactory clinical condition, with a mean forced expired volume in 1 second of 59% +/- 13% of predicted (repeat double lung transplant recipients) or 41% +/- 6% of predicted (repeat single lung transplant recipients). We conclude that pulmonary retransplantation for obliterative bronchiolitis is associated with significantly worse survival than after primary lung transplantation. The absence of an old contralateral graft after retransplantation and reoperation after 1989 are important predictors of survival. Additional data and follow-up are required to determine the merit of pulmonary retransplantation for obliterative bronchiolitis.
Asunto(s)
Bronquiolitis Obliterante/cirugía , Trasplante de Pulmón , Análisis Actuarial , Adulto , Bronquiolitis Obliterante/mortalidad , Estudios de Cohortes , Europa (Continente)/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Trasplante de Pulmón/mortalidad , Masculino , Modelos de Riesgos Proporcionales , Sistema de Registros , Reoperación/mortalidad , Factores de Tiempo , Estados Unidos/epidemiologíaRESUMEN
A case control study was performed to determine whether previous implantable cardioverter-defibrillator (ICD) insertion adversely affects outcome after heart transplantation. Six male heart transplant recipients who had undergone ICD insertion 12 +/- 5 months before heart transplantation were compared to a cohort of six heart transplant recipients who were matched according to age, preoperative status and hemodynamics, date of transplantation, graft ischemic time, history of a previous cardiac operation, and duration of follow-up. There were no significant differences in operating room time, chest tube drainage, time to extubation, and the duration of intensive care unit or hospital stay between the two groups. Furthermore, there were no significant differences in the number of units of packed cells, fresh frozen plasma, platelets and cryoprecipitate transfused. The number of treated rejection episodes and the number of patients requiring intravenous antibiotics for infection in the first 90 days was identical between groups. It was concluded that heart transplantation after ICD implantation did not appear to carry more risk than heart transplantation after a previous cardiac operation. Our limited experience supports the potential use of the ICD in patients with life-threatening ventricular dysrhythmias who are awaiting transplantation.
Asunto(s)
Desfibriladores Implantables/efectos adversos , Trasplante de Corazón , Pérdida de Sangre Quirúrgica , Transfusión Sanguínea , Estudios de Casos y Controles , Rechazo de Injerto , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Complicaciones PosoperatoriasRESUMEN
Since the last review on lung preservation in 1985, enormous progress has been made in experimental and clinical lung transplantation. This comprehensive review examines recent advances in the experimental laboratory in optimizing conditions during organ procurement, lung storage, and reperfusion to minimize ischemia-reperfusion injury in lung allografts.
Asunto(s)
Trasplante de Pulmón , Pulmón , Preservación de Órganos/tendencias , Daño por Reperfusión/prevención & control , Animales , Soluciones Cardiopléjicas , Frío , Humanos , Preservación de Órganos/métodos , Premedicación , Donantes de Tejidos , Obtención de Tejidos y Órganos/tendenciasRESUMEN
An international survey of redo lung transplantation was performed to identify the morbidity and mortality rates and factors correlating with increased or decreased survival after this procedure. Twenty institutions in North America and Europe participated, and the study cohort included 61 patients who underwent 63 redo lung transplantation operations. Patients undergoing a redo heart-lung transplantation were excluded. The indications for reoperation included obliterative bronchiolitis (32 patients), graft failure (14 patients), intractable airway problems (8 patients), severe acute lung rejection (5 patients), and miscellaneous complications (4 patients). Five types of retransplantation procedures were performed, including redo ipsilateral single lung transplantation (24 patients), redo contralateral single lung transplantation (11 patients), single lung transplantation after double lung or heart-lung transplantation (13 patients), redo double lung transplantation (8 patients), and double lung transplantation after a previous single lung transplantation (7 patients). Actuarial survival was 65%, 49%, 42%, 35%, and 32% at 1, 3, 6, 12, and 24 months, respectively; survival was significantly (p < 0.05) worse than that of first-time lung transplant recipients recorded in the International Society for Heart and Lung Transplantation Registry. Actuarial survival did not differ according to the original diagnosis of the recipients, the indication for reoperation, or the type of retransplantation procedure performed. Similarly, recipient cytomegalovirus status and ventilator status before reoperation did not affect postoperative survival. Trends toward an improved outcome were noted in patients who were ambulatory before reoperation and in those receiving an ABO identical, as opposed to ABO compatible, graft at reoperation. Life table and step-wise logistic regression analysis identified donor cytomegalovirus status at reoperation to be an important determinant of outcome, with significantly (p < 0.05) improved survival in the donor cytomegalovirus-negative group. Polymicrobial infection was the most common cause of death at all time intervals after reoperation. The presence of disseminated infection and established multiorgan failure was almost uniformly associated with a fatal outcome. We conclude that redo lung transplantation may be indicated only in well-selected patients with obliterative bronchiolitis, severe airway complications, or graft failure. Donor cytomegalovirus status at reoperation is an important predictor of survival. The presence of disseminated infection and established multiorgan failure should be contraindications to lung retransplantation.
Asunto(s)
Trasplante de Pulmón , Adolescente , Adulto , Anticuerpos Antivirales/análisis , Bronquiolitis Obliterante/etiología , Causas de Muerte , Niño , Preescolar , Citomegalovirus/inmunología , Femenino , Rechazo de Injerto , Histocompatibilidad , Humanos , Trasplante de Pulmón/efectos adversos , Trasplante de Pulmón/mortalidad , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Reoperación/mortalidad , Tasa de SupervivenciaRESUMEN
Of 219 heart transplant patients with follow up for at least 3 months after transplantation, cardiac allograft ischemic time was more than 4 hours in 28% and more than 5 hours in 10%. In 1988 and 1989 grafts with ischemic times longer than 4 hours were used in 44% and 45% of cases, respectively. Overall, donor age has been 35 or more years in 22% and 45 or more in 9%. In 1989 donor age was 35 or more years in 39% of cases and 45 or more in 18%. Fifteen of 20 grafts from donors 45 years or older were used for patients aged 50 or older. There was no relationship between donor age or ischemic time and 90-day graft loss. At 3 and 12 months, cardiac function, assessed by treadmill exercise duration, radionuclide angiography, and rest and peak supine exercise hemodynamics, was also unrelated to donor age or ischemic time. Therefore by careful selection of appropriate donors, extending both graft ischemic time and donor age has increased the potential donor pool and has not to date been associated with increased graft loss or adverse effects on cardiac function 3 months and 1 year after heart transplantation.
Asunto(s)
Trasplante de Corazón/mortalidad , Preservación de Órganos , Donantes de Tejidos , Adulto , Femenino , Estudios de Seguimiento , Supervivencia de Injerto , Trasplante de Corazón/fisiología , Humanos , Terapia de Inmunosupresión , Masculino , Persona de Mediana Edad , Factores de Tiempo , Obtención de Tejidos y ÓrganosRESUMEN
Chronic shortage of donor organs has heightened interest in new strategies for increasing donor availability. Unacceptable hearts for transplant have previously been characterized by donor age greater than 40 years, more than 20% donor/recipient weight mismatch, ischemic time more than 4 hours, and the presence of coronary artery disease. A series of 185 consecutive orthotopic heart transplants were retrospectively examined. A significant number of donor hearts used were unacceptable by one or more of the above criteria. Our current approach is to match donors to recipients using a wide range of criteria. Donors are now accepted from any location in North America. We have accepted donors more than 55 years of age and donors weighing less than 50% of the recipient's body weight. Because of the chronic shortage of donor organs, donor criteria have been effectively liberalized, thereby increasing the donor pool without compromising the overall results of heart transplantation.
Asunto(s)
Cardiomiopatía Dilatada/cirugía , Enfermedad Coronaria/cirugía , Trasplante de Corazón , Donantes de Tejidos , Obtención de Tejidos y Órganos , Análisis Actuarial , Adulto , Peso Corporal , Gasto Cardíaco/fisiología , Femenino , Trasplante de Corazón/mortalidad , Trasplante de Corazón/fisiología , Humanos , Masculino , Estudios Retrospectivos , Volumen Sistólico/fisiologíaRESUMEN
BACKGROUND AND METHODS: To evaluate the physiologic basis for the suboptimal peak oxygen uptake observed after heart transplantation, we calculated the functional aerobic impairment ([(peak predicted oxygen uptake-peak observed oxygen uptake)/peak predicted oxygen uptake] x 100) and related it to donor/recipient, operative, and maximal exercise variables. Fifty-seven heart transplant recipients (mean age 50 +/- 10 years, 1 to 9 years after transplantation) underwent maximal upright cycle exercise testing. Concomitant exercise central hemodynamic measurements were obtained in 36 patients (63%). RESULTS: The mean peak oxygen uptake was 21.7 +/- 6.5 ml/kg/min and functional aerobic impairment was 34% +/- 17%. Functional aerobic impairment correlated positively (p < 0.01) with peak systemic vascular resistance (r = 0.55) and negatively with peak cardiac index (r = -0.62) and peak systemic arteriovenous oxygen difference (r = -0.66). A weak correlation was found between functional aerobic impairment and the duration of cardiac disease (r = 0.35, p < 0.01) but not the origin of heart failure. No correlation was seen between functional aerobic impairment and donor age, total ischemic time, time since transplantation, recipient age, and resting and exercise right and left ventricular filling pressures. CONCLUSIONS: These results suggest that the decreased exercise capacity observed in heart transplant recipients is in part due to increased peripheral vascular resistance and decreased oxygen extraction possibly due to skeletal muscle atrophy. These factors may be the result of irreversible changes from long-standing heart disease, deconditioning, or the effect of cyclosporine and prednisone.
Asunto(s)
Prueba de Esfuerzo , Trasplante de Corazón/fisiología , Oxígeno/fisiología , Complicaciones Posoperatorias/fisiopatología , Adulto , Femenino , Estudios de Seguimiento , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiopatología , Aptitud Física/fisiología , Complicaciones Posoperatorias/diagnóstico , Resistencia Vascular/fisiologíaRESUMEN
BACKGROUND: The advances in immunotherapy, along with a liberalization of eligibility criteria have contributed significantly to the ever increasing demand for donor organs. In an attempt to expand the donor pool, transplant programs are now accepting older donors as well as donors from more remote areas. The purpose of this study is to determine the effect of donor age and organ ischemic time on survival following orthotopic heart transplantation (OHT). METHODS: From April 1981 to December 1996 372 adult patients underwent OHT at the University of Western Ontario. Cox proportional hazards models were used to identify predictors of outcome. Variables affecting survival were then entered into a stepwise logistic regression model to develop probability models for 30-day- and 1-year-mortality. RESULTS: The mean age of the recipient population was 45.6 +/- 12.3 years (range 18-64 years: 54 < or = 30; 237 were 31-55; 91 > 56 years). The majority (329 patients, 86.1%) were male and the most common indications for OHT were ischemic (n = 180) and idiopathic (n = 171) cardiomyopathy. Total ischemic time (TIT) was 202.4 +/- 84.5 minutes (range 47-457 minutes). In 86 donors TIT was under 2 hours while it was between 2 and 4 hours in 168, and more than 4 hours in 128 donors. Actuarial survival was 80%, 73%, and 55% at 1, 5, and 10 years respectively. By Cox proportional hazards models, recipient status (Status I-II vs III-IV; risk ratio 1.75; p = 0.003) and donor age, examined as either a continuous or categorical variable ([age < 35 vs > or = 35; risk ratio 1.98; p < 0.001], [age < 50 vs > or = 50; risk ratio 2.20; p < 0.001], [age < 35 vs 35-49 versus > or = 50; risk ratio 1.83; p < 0.001]), were the only predictors of operative mortality. In this analysis, total graft ischemic time had no effect on survival. However, using the Kaplan-Meier method followed by Mantel-Cox logrank analysis, ischemic time did have a significant effect on survival if donor age was > 50 years (p = 0.009). By stepwise logistic regression analysis, a probability model for survival was then developed based on donor age, the interaction between donor age and ischemic time, and patient status. CONCLUSIONS: Improvements in myocardial preservation and peri-operative management may allow for the safe utilization of donor organs with prolonged ischemic times. Older donors are associated with decreased peri-operative and long-term survival following. OHT, particularly if graft ischemic time exceeds 240 minutes and if these donor hearts are transplanted into urgent (Status III-IV) recipients.