Prognostic Value of NT

In patients with mildly dilated cardiomyopathy (MDCM), although no evidence has supported the prognostic role played by N-terminal pro-brain natriuretic peptide (NT-proBNP) levels, increased concentrations of high-sensitivity C-reactive protein (hs-CRP) were associated with patient outcomes. These findings were published in the journal ESC Heart Failure.

A retrospective analysis was conducted among hospitalized patients with dilated cardiomyopathy (DCM) and a left ventricular ejection fraction of 50% or less at Fuwai Hospital in Beijing, China, between December 2006 and October 2017. The researchers sought to compare the prognostic value of the biomarkers NT-proBNP and hs-CRP between patients with MDCM and those with DCM. In this study, MDCM was defined as left ventricular end-diastolic diameter index (LVEDDi) of 33 mm/m2 or smaller in men and 34 mm/m2­ smaller in women.

A total of 640 participants were included in the analysis, with 17% of them categorized as having MDCM and 83% as having DCM at baseline. Overall, 24.8% of the participants were women. Patients were median aged 49 years.

Compared with participants with DCM, those with MDCM were younger, had higher blood pressure, higher rates of diabetes, lower rates of nonsustained ventricular tachycardia, higher body mass index, and shorter lengths of hospital stay. Regarding cardiac biomarkers, patients with MDCM had significantly lower median NT-proBNP levels compared with patients with DCM (2203 pg/mL vs 1448 pg/mL, respectively; P <.001). Median hs-CRP levels, in contrast, were higher among patients with MDCM than among those with DCM (3.09 mg/L vs 2.79 mg/L, respectively; P =.39).

Among 282 patients who received follow-up echocardiography separated by 6 months or longer, 7 patients with MDCM (11.1%) evolved to DCM, whereas 70 patients with DCM (32.0%) recovered to MDCM, as observed in changes in LVEDDi.

Compared with participants with DCM, those with baseline MDCM had lower composite risks for all-cause mortality, receiving heart transplantation, and rehospitalization for heart failure (adjusted hazard ratio [aHR], 0.63; 95% CI, 0.43-0.93; P =.019).

Both hs-CRP and NT-proBNP levels were independently associated with the composite endpoint in the overall study cohort (hs-CRP, aHR, 1.07; 95% CI, 1.00-1.15 and NT-proBNP: aHR, 1.11; 95% CI, 1.02-1.22; P =.019).

After propensity-score matching between MDCM and DCM, the association between high NT-proBNP level and the composite endpoint was consistent with that reported prior to matching in patients with DCM (HR, 1.83; 95% CI, 1.05-3.20; P =.034), but not in those with MDCM (HR, 1.54; 95% CI, 0.76-3.11; P =.227). In contrast, hs-CRP levels were still significantly associated with prognosis in patients with MDCM (HR, 3.19; 95% CI, 1.52-6.66; P =.002), but not in those with DCM (HR, 1.04; 95% CI, 0.61-1.79; P =.88).

A limitation of the study is the fact that the phenotype of a patient might change during follow-up, although the number of individuals who received a follow-up echocardiogram was rather small, so predictors of change in phenotypes were not analyzed. Further, since the sample size of patients with MDCM in the study is small, potential confounders were not fully adjusted in the multivariable analysis.

"Baseline hs-CRP was associated with the composite outcome in MDCM patients before and after adjusting covariates, while NT-proBNP was only associated with the outcome in DCM," the study authors noted. "Future research is needed to investigate the predictors of changes in ventricular geometry and cardiac function especially in MDCM patients to provide more precise risk stratification."

Disclosure: None of the study authors has declared affiliations with biotech, pharmaceutical, and/or device companies.

Feng J, Tian P, Liang L, et al. Outcome and prognostic value of N-terminal pro-brain natriuretic peptide and high-sensitivity C-reactive protein in mildly dilated cardiomyopathy vs. dilated cardiomyopathy. ESC Heart Fail. Published online March 4, 2022. doi:10.1002/ehf2.13864