Inflammatory Mediators and Clinical Outcome in Patients With Advanced Heart Failure Receiving Cardiac Resynchronization Therapy.

Expression of different cytokines and growth factors after myocardial injury has been associated with fibroplasia and dilatation versus reverse remodeling and myocardial repair. Specifically, the proinflammatory/fibrotic mediators: interleukin (IL)-6, epidermal growth factor, and fibroblast growth factor (FGF)-2 cause fibroplasia, whereas reparative cytokines including: IL-1α, IL-1ß, IL-4, and IL-13 can limit fibrosis. In appropriate patients, cardiac resynchronization therapy (CRT) reverses cardiomyopathy and improves outcome. However, a significant proportion will not respond to this therapy. We conducted this study to assess the association of proinflammatory/fibrotic and/or reparative immune response mediators at baseline with outcome after CRT. In the multicenter RISK study, plasma samples were collected prospectively before CRT implantation. Plasma IL-6, epidermal growth factor, FGF-2, IL-1α, IL-1ß, IL-4, and IL-13 were evaluated by Luminex technology. The primary outcome was predefined as freedom from heart failure hospitalization or death and a decrease in echocardiographic end-systolic volume of >15% at 12 months. To determine associations with the outcome, multivariate logistic regression models including baseline clinical characteristics and the specific cytokines and growth factors were constructed. On multivariate analysis of 257 patients, detectable reparative cytokine IL-13 was significantly associated with the primary outcome (odds ratio 3.79; 95% CI 2.10 to 6.82, p <0.0001). In contrast, detectable proinflammatory/fibrotic growth factor FGF-2 was negatively associated (odds ratio 0.31; 95% CI, 0.14 to 0.68; p = 0.004). In conclusion, in CRT recipients, baseline levels of inflammatory mediators affecting cardiac fibrosis versus repair were associated with subsequent clinical outcome.

Association of BNP and Troponin Levels with Outcome among Cardiac Resynchronization Therapy Recipients.

BACKGROUND: We conducted a prospective multicenter study to assess the prognostic value of combined baseline preimplant plasma levels of the biomarkers cardiac troponin T (TnT) and B-type natriuretic peptide (BNP) among cardiac resynchronization therapy (CRT) with or without defibrillator capability (CRT-D) recipients. METHODS: At CRT-D implant, patients were stratified based on detectable TnT (≥0.01 ng/mL) and elevated BNP (predefined as >440 pg/mL) levels. Patients were classified into three groups: high (both detectable TnT and high BNP), intermediate (either detectable TnT or high BNP), or low (nondetectable TnT and low BNP). Patients were followed for 12 months. Survival curves free from mortality or heart failure hospitalizations (HFH) were assessed. To assess the predictive value of biomarker category, we constructed a multivariate Cox regression model, including the covariates of age, New York Heart Association class, left ventricular ejection fraction (LVEF), and QRS duration. RESULTS: A total of 267 patients (age 66 ± 12 years, males 80%, LVEF 25% ± 8%, ischemic cardiomyopathy 52%, QRSd 155 ± 26 ms) were studied. After 1 year, there were 13 deaths and 25 HFH events. A significant difference in event-free survival among the three groups was observed, with high and intermediate categories having worse survival than low (log-rank test, P < 0.001). In the multivariate model, risk category was a significant predictor of outcome: hazard ratios were 7.34 (95% confidence interval [CI]: 2.48-21.69) and 2.50 (95% confidence interval [CI]: 1.04-6.04) for high-risk and intermediate-risk groups, respectively (P < 0.0001). CONCLUSION: Among CRT-D recipients, baseline TnT and BNP values alone or in combination provide significant prognostic value for the outcome of mortality or HFH.