Prophylaxis versus preemptive anti-cytomegalovirus approach for prevention of allograft vasculopathy in heart transplant recipients.

BACKGROUND: Cytomegalovirus (CMV) infection may influence the development of cardiac allograft vasculopathy (CAV). Prophylactic or preemptive administration of anti-CMV agents effectively prevents acute CMV manifestations. However, studies comparing allograft-related outcomes between these anti-CMV approaches are lacking. Herein we report a longitudinal observational study comparing CAV development between prophylactic and preemptive approaches. METHODS: The 1-year change in maximal intimal thickening (MIT) assessed by intravascular ultrasound at 1 and 12 months after heart transplantation (the major surrogate for late survival) was compared in groups of patients routinely assigned to a preemptive strategy (from November 2004 to October 2005; n = 21) or receiving valganciclovir prophylaxis (from November 2005 to October 2006; n = 19). CMV infection was monitored with pp65 antigenemia. RESULTS: The 1-year increase in MIT was significantly lower in patients receiving prophylaxis compared with those managed preemptively (0.15 +/- 0.17 vs 0.31 +/- 0.20 mm; p = 0.01). Prophylaxed recipients presented less frequently with MIT change > or =0.3 mm (p = 0.03) and > or =0.5 mm (p = 0.10) than those managed preemptively. Prophylaxis was also associated with later onset of CMV infection (p = 0.01), lower peak CMV detection (p < 0.01) and reduced incidence of CMV disease/syndrome (p = 0.04). After adjusting for metabolic risk factors and other possible confounders, prophylaxis remained independently associated with lower risk for MIT change > or =0.3 mm (odds ratio = 0.09, 95% confidence interval 0.01 to 0.93; p = 0.04). CONCLUSIONS: Universal prophylaxis was associated with delayed onset of CMV infection, lower viral burden, reduced CMV disease/syndrome and less intimal thickening, as compared with a preemptive anti-CMV approach. Randomized studies are required to confirm the potential benefits of prophylaxis vs a preemptive approach in heart transplant recipients.

Static and dynamic predictors of adverse events in patients with intermediate cardiopulmonary capacity referred for heart transplantation.

BACKGROUND: Chronic heart failure (CHF) patients with intermediate cardiopulmonary capacity referred for heart transplantation are at "medium risk," and are not amenable to further stratification based solely on peak VO(2.) Accordingly, we analyzed whether time-related and/or non-time-related parameters could provide incremental prognostic information in CHF patients with intermediate cardiopulmonary capacity. METHODS: We analyzed 134 patients with a peak VO(2) of 10 to 18 ml/kg/min (age 54 +/- 9 years, 66% males) and a left ventricular ejection fraction (LVEF) of 27% +/- 8% who underwent an extensive clinical/instrumental (electrocardiogram, echocardiogram, cardiopulmonary exercise test) index evaluation; for all patients, an equivalent pre-study evaluation (performed >or=6 months before) was also available. RESULTS: Among index-evaluation parameters, systolic blood pressure (p < 0.001), LVEF (p = 0.036), and presence of severe mitral regurgitation (p = 0.006) independently predicted cardiac death/need for heart transplantation. Stable clinical condition from pre-study to index-evaluation accompanied by <10% QRS widening and <10% decrease in peak VO(2) provided incremental prognostic information with respect to all index-evaluation parameters (p = 0.014). CONCLUSIONS: CHF patients with intermediate peak VO(2) who display "stable" CHF present a lower incidence of adverse cardiac events, particularly in the absence of hypotension, severe mitral regurgitation, and severe reduction of LVEF. Such a stratification might be clinically useful for deciding between medical treatment alone and consideration for heart transplantation.

Homocysteine-lowering therapy and early progression of transplant vasculopathy: a prospective, randomized, IVUS-based study.

Although observational studies suggest that hyperhomocysteinemia may be a risk factor for coronary allograft vasculopathy (CAV), prospective data on homocysteine-lowering interventions and CAV development are lacking. We, therefore, randomized 44 de novo heart transplant (HT) recipients to 15 mg/day of 5-methyl-tetrahydrofolate (n=22), or standard therapy (control group, n=22) to investigate the effect of homocysteine lowering on the change in coronary intimal hyperplasia during the first 12 months after transplant, as detected by intra-vascular ultrasound (IVUS). Although 12 months after HT, homocysteinemia was lower in folate-treated patients (p<0.001), coronary intimal area increased similarly in the two groups (p>0.4). Conversely, hypercholesterolemia and cytomegalovirus infection were both associated with increased intimal hyperplasia (p<0.04), independently from folate intake. Sub-group analysis revealed that folate therapy reduced intimal hyperplasia in patients with hyperhomocysteinemia before randomization (n=19; p=0.02), but increased intimal hyperplasia in patients with normal homocysteine plasma concentrations (p=0.02). This bimodal effect of folate therapy persisted significantly after adjusting for cytomegalovirus infection and hypercholesterolemia. Despite effective in prevent hyperhomocysteinemia after heart transplantation, folate therapy does not seem to affect early CAV onset. However, sub-group analysis suggests that folate therapy may delay CAV development only in patients with baseline hyperhomocysteinemia, while may favor CAV progression in recipients with normal baseline homocysteinemia.