Elevated levels of serum interleukin-6 are associated with low grade cellular rejection in patients with heart transplantation.

UNLABELLED: Endomyocardial biopsy is the gold-standard procedure to diagnose acute cellular rejection after heart transplantation. This study assessed whether the blood levels of cytokines involved in inflammation and immune activation are useful to detect the presence of acute cellular rejection. METHODS: Blood specimens collected before 275 endomyocardial biopsies in 66 patients were assayed for levels of TNFalpha, IL6, IL1beta, and IL2 receptor. The biopsies were grouped according to the presence (n = 41) or absence (n = 234) of acute cellular rejection grade > or = 3A of the International Society for Heart and Lung Transplantation. We compared the levels of cytokines in the two groups. RESULTS: Circulating IL6 levels were significantly higher when there was a low grade (0-2) cellular rejection in the biopsy versus the group of biopsies grade > or = 3A (19.8 +/- 27 versus 12.9 +/- 10 pg/mL; P = .001). An IL6 level higher than 30 pg/mL showed a negative predictive value of 95% for the presence of acute rejection grade > or = 3A. CONCLUSION: In heart transplant patients, high levels of serum IL6 were associated with low grade cellular rejection. Determination of IL6 levels may be useful to reduce the number of endomyocardial biopsies during follow-up in these patients.

Value of NT-proBNP determinations in the follow-up of heart transplantation.

BACKGROUND: The N-terminal pro-brain natriuretic peptide (NT-proBNP) has been useful in the diagnosis and follow-up of heart failure. Whether it can be useful in the detection of acute rejection (AR) after heart transplantation (HT) has not been addressed. Our aim was to assess the prognostic value of NT-proBNP determinations after HT. METHODS: We analyzed 137 endomyocardial biopsies (EMB) performed in 51 patients as assessment of AR and correlated them with NT-proBNP determinations. The value of NT-proBNP in the early follow-up of the novo HT was also assessed. RESULTS: AR grade > or =3A was diagnosed in 10 of the 137 performed biopsies. There were no significant differences in NT-proBNP values between patients with or without AR (1047 +/- 629 versus 1886 +/- 3026 pg/mL, P = NS). There were 24 de novo HT, in these patients increased NT-proBNP levels showed an inverse significant correlation with time since HT (r = -0.40, P = .0001). During follow-up, 15 of the novo HT had a descending NT-proBNP curve over time, and in the remaining 9 (37%) a late increase of NT-proBNP values were observed. Those 9 patients had the following complications: AR > or =3A in 5 cases, 1 death, 2 required a permanent pacemaker, and in the last patient a significant EMB could not be obtained. CONCLUSIONS: NT-proBNP values follow a descending curve early after HT. During the first months, a late increase of NT-proBNP value was associated with HT complications, with AR being the most frequent. Isolated increased NT-proBNP levels were not useful for the detection of AR. More studies are needed to establish the prognostic value of NT-proBNP after HT.

Experience with single-dose daclizumab in the prevention of acute rejection in heart transplantation.

INTRODUCTION: Daclizumab is a monoclonal antibody that binds to the interleukin-2 receptor. It has been used as induction therapy in heart transplantation with two to five repeated administrations over several weeks. The objective of our study was to estimate the efficacy and safety of induction therapy with only one dose of daclizumab in a consecutive series of patients undergoing heart transplantation. METHODS: Thirty-two consecutive heart transplants performed since July 2002, who received single-dose daclizumab as induction therapy, were compared with the 30 patients transplanted previously, who received OKT3. In both groups, maintenance immunosuppression included cyclosporine or tacrolimus, mycophenolate mofetil, and corticosteroids. Follow-up time was 1 year. RESULTS: There were no baseline differences between the two groups regarding age, gender, or etiology. In the group treated with daclizumab there were more diabetics (43% versus 10%, P = .01) and the ischemia time was longer (192 versus 156 minutes, P = .03). During the first posttransplant year, 76% of patients treated with OKT3 and 55% of those treated with daclizumab presented acute rejection > or =3A; 20% and 25%, respectively, presented infections; and 5 (17%) patients in the OKT3 group and 2 (6%) in the group treated with daclizumab died. None of these differences was statistically significant. CONCLUSIONS: Our experience suggests that induction therapy with a single-dose regimen of daclizumab seems to have an efficacy and safety profile similar to OKT3, and it is easier to administer and has a lower cost than other induction regimens.

Impairment in forearm endothelium-dependent vasodilation after heart transplantation.

BACKGROUND: Endothelial dysfunction has been found in the peripheral circulation of patients with severe heart failure. However, whether the endothelial dysfunction improves after heart transplantation remains unknown. Our aim was to assess the forearm endothelium-dependent vasoreactivity one and six months after heart transplantation. METHODS: We studied 12 patients using high resolution brachial artery ultrasound to assess flow-mediated dilation induced by reactive hyperemia and nitroglycerin induced dilation (NTGdil). RESULTS: One month after heart transplantation, endothelium-dependent vasodilation was significantly impaired in 10 patients (83%), while it was preserved in the remaining two (17%) (0.4%+/-2.4% vs 9.9%+/-4.6%, respectively, P=.001). NTGdil was normal in both groups (12%+/-10% vs 23%+/-5%, respectively, P=NS). At six months, endothelial dysfunction was present in all patients including the two patients without endothelial dysfunction at the first study. CONCLUSIONS: The present study demonstrates that peripheral endothelial dysfunction is present after heart transplantation despite the improvement in left ventricular function. More studies are needed to prove if endothelial dysfunction reversion may improve survival in heart transplantation.