Exercise tolerance after beta blockade in recent cardiac transplant recipients.

OBJECTIVE: Exercise capacity has been shown to be reduced among cardiac transplant recipients. This observation is directly connected to both the transplanted heart's dependence on circulating catecholamines and the abnormal sympathoadrenal response to exercise in these patients. Taking into account this background, there is reluctance to use beta-blockers after heart transplantation. Nevertheless, this point remains controversial. Our aim was to examine exercise tolerance after an oral dose of atenolol early after cardiac transplantation. MATERIALS AND METHODS: Eighteen nonrejecting, otherwise health, cardiac transplant recipients were included in this study at a mean of 61.9 +/- 25.6 days after surgery; 13 were men. Patients performed controlled exercise to a symptom-limited maximum before and 2 hours after taking an oral dose of atenolol. Heart rate, blood pressure, exercise time, and metabolic equivalent units (METS) were recorded at rest as well as during and after exercise. We compared results depending on taking atenolol. RESULTS: Resting (101.7 +/- 14.5 vs 84 +/- 12.4 bpm; P = .001) and peak heart rates (128.5 +/- 12.9 vs 100.7 +/- 16 bpm; P = .001) were significantly higher before than after beta blockade. Resting systolic blood pressure was slightly higher before compared with after beta blockade (129.3 +/- 23.6 vs 122.2 +/- 20.3 mm Hg; P = .103). However, there was neither a significant difference in the length of exercise (3.17 +/- 1.96 vs 3.40 +/- 2.48 minutes; P = .918) nor in the estimated oxygen consumption (METS; 5.07 +/- 1.8 vs 5.31 +/- 2.2; P = .229). Furthermore, no patient reported a greater degree of tiredness after beta blockade. CONCLUSIONS: This study showed little adverse effect on exercise tolerance by beta blockade in recently transplanted patients. Atenolol seemed to be safe in this context.

Effect of circulatory assistance on premature death and long-term prognosis.

BACKGROUND: Patients undergoing urgent heart transplantation (HT) have a poorer prognosis and more long-term complications. The objective of this study was to compare the preoperative course in patients undergoing urgent HT according to the need for preoperative intra-aortic balloon counterpulsation (IABP). MATERIALS AND METHODS: We studied 102 consecutive patients including 23 patients with IABP who underwent urgent HT between January 2000 and September 2006. We excluded patients who received combination transplants, those who underwent repeat HT, and pediatric patients who underwent HT. The statistical methods used were the t test for quantitative variables and the chi(2) test for qualitative variables. A logistic regression model was constructed to assess the possible relationship between IABP and other variables on premature death within 30 days after HT. RESULTS: Mean (SD) patient-age was 50 (10) years. No significant differences were observed in baseline characteristics between the IABP and the non-IAPB groups. The IABP patient group had higher rates of acute graft failure (45.5% vs 35.4%; P = .46) and premature death (18.8% vs 14.8%; P = .67) and shorter long-term survival (40.6 [34.9] vs 54.5 [43.7] mo; P = .30). Multivariate analysis demonstrated no association between the need for IABP and increased frequency of premature death. CONCLUSIONS: Use of IABP is not associated with premature or late death. We recommend use of IABP in patients with acute decompensated heart failure to stabilize them before HT.

Effect of clinical trials on survival after heart transplantation.

UNLABELLED: The application of clinical trials (CTs) to daily practice is based on the assumption that the patients included in these trials are similar to those seen on a daily basis. We performed a retrospective study to evaluate patient survival depending on whether they were included in a CT. We studied 217 patients who underwent heart transplantation (HT) between January 2000 and September 2006. We excluded patients who received combination transplants, those who underwent repeat HT, and pediatric patients who underwent HT. In total, 54 patients were included in a CT and 163 were not (NCT). The statistical tests included the t test, the chi(2) test and the Kaplan-Meier method. RESULTS: Patients in the NCT group were in worse condition at HT, with a greater percentage of inotropic treatments pre-HT (36% vs 17%; P = .005), emergency transplants procedures (30% vs 13%; P = .01), and worse functional status pre-HT (P = .03). The NCT group exhibited lower survival (80.37% vs 87.04%; P = 0.13, log-rank test). There were no significant differences in the other analyzed variables. CONCLUSIONS: Patients included in CTs tend to have better long-term survival rates, for several reasons: patients in the CT group were more stable at HT (selection bias), and the close follow-up of patients in CTs makes it more likely that any complication will be detected and treated early (follow-up bias).

Effect of hypertension, diabetes, and smoking on development of renal dysfunction after heart transplantation.

BACKGROUND: Renal dysfunction is a serious problem after heart transplantation (HT). The objective of this study was to determine the cardiovascular risk factors associated with medium- to long-term dysfunction after HT. MATERIALS AND METHODS: We studied 247 consecutive patients who underwent HT between January 2000 and September 2006 who survived for at least 6 months. We excluded patients receiving combination transplants, those undergoing repeat HT, and pediatric patients undergoing HT. Mean (SD) follow-up was 72 (42) months. We defined renal dysfunction as serum creatinine concentration greater than 1.4 mg/dL during follow-up. Patients were considered to be smokers if they had smoked during the six months before HT, to have hypertension if they required drugs for blood pressure control, and to have diabetes if they required insulin therapy. Statistical tests included the t test and the chi(2) tests. We performed Cox regression analysis using significant or nearly significant values in the univariate analysis. RESULTS: Mean (SD) age of the patients who underwent HT was 52 (10) years, and 217 (87.9%) were men. Renal dysfunction was detected during follow-up in 135 (54.5%) patients. The significant variables at univariate analysis were smoking (61.4% vs. 43.2%; P = .01) and previous renal dysfunction (94.1% vs 52.7%; P = .001). Nearly significant variables were the presence of hypertension before HT (63.8% vs 51.1%; P = .09) and after HT (58.2% vs 44.8%; P = .082). At multivariate analysis, pre-HT smoking and previous renal dysfunction were significant correlates (P = .04 and P = .01, respectively). CONCLUSIONS: Renal dysfunction is common after HT. In our analysis, the best predictors were pre-HT dysfunction and smoking. Less important factors were advanced age and post-HT hypertension.

Hypertension after heart transplantation: predictive factors and number and classes of drugs for its management.

BACKGROUND: This study was performed to determine the factors that cause arterial hypertension after heart transplantation (HT) and the drugs used in its management. MATERIALS AND METHODS: We studied 247 consecutive patients who had undergone HT between 2000 and 2006 and who survived for at least 6 months. We excluded patients who received combination transplants, those who underwent repeat transplantation, and pediatric patients who had received transplants. Hypertension was defined as the need to use drugs for its control. Renal dysfunction was defined as serum creatinine concentration greater than 1.4 mg/dL, and diabetes as the need for an antidiabetes drug for its control. Statistical analyses were performed using the t test, the chi(2) test, and Cox regression. RESULTS: Mean (SD) patient age was 52 (10) years, and 87.4% of the patients were men. Follow-up was 72 (42) months. Hypertension was present in 33.3% of patients before HT and in 71.1% at some time after HT. The number of drugs used to control hypertension was 1.3 (0.5); one drug was used in 72.9% of patients. The most often used single class of drugs were calcium channel blockers (63.2%), followed by angiotensin-converting enzyme inhibitors (20%), and angiotensin receptor blockers (15.8%). Only pre-HT hypertension was significantly associated with greater use of antihypertensive drugs post-HT (mean [SD], 1.48 [0.65] vs 1.22 [0.41]; P = .005). At univariate analysis, only pre-HT hypertension was associated with the presence of post-HT hypertension (80.5% vs 65.5%; P = .02). At Cox regression analysis, recipient age (P = .02) and pre-HT hypertension (P = .004) were associated with post-HT hypertension. CONCLUSIONS: Hypertension is common after HT; however, in most patients, it can be controlled with a single antihypertensive agent. The most important factors in the development of hypertension are the presence of pre-HT hypertension and advanced age.

Influence of traditional cardiovascular risk factors in the recipient on the development of cardiac allograft vasculopathy after heart transplantation.

BACKGROUND: Cardiac allograft vasculopathy (CAV) is the leading cause of death heart transplant (HT) recipients after the first year. We assessed the influence of cardiovascular risk factors (CVRFs) in HT recipients on the development of CAV after 1 year of follow-up. MATERIALS AND METHODS: From 2001 to 2005, we studied 72 patients who received a HT and survived for at least 1 years. All patients underwent coronary arteriography and intravascular ultrasonography at 1 year after HT. Cardiac allograft vasculopathy was defined as intimal proliferation of 0.5 mm or more. The analyzed CVRFs were age, sex, body mass index, diabetes mellitus, hypertension, dyslipidemia, and smoking. We also considered the heart disease that was the reason for HT. The statistical tests used in the univariate analysis were the t and chi(2) tests. Logistic regression was performed with the variables obtained at univariate analysis. RESULTS: Mean (SD) recipient age at HT was 51 (9) years. Eighty patients (90.5%) were men. Dyslipidemia was significantly associated with a greater incidence of CAV at 1 year (68.3% vs 41.9%; P = .03). Ischemia, as opposed to all other causes, was also significantly associated with CAV (69.4% vs 44.4%; P = .03). Older age, hypertension, smoking history, and high body mass index were associated with a higher incidence of CAV, albeit without statistical significance. At multivariate analysis, dyslipidemia was the most significant CVRF (P = .045) for the development of CAV. CONCLUSIONS: Recipient dyslipidemia is a risk factor for the development of CAV in HT. The remaining traditional CVRFs are more weakly associated with CAV. After HT close monitoring of recipients with pretransplantation CVRFs is essential for early detection of CAV.