Vitamin D receptor genetics on extracellular matrix biomarkers and hemodynamics in systolic heart failure.

INTRODUCTION: Vitamin D deficiency has been associated with the development of myocardial hypertrophy and inflammation. These findings suggest that vitamin D status and vitamin D receptor (VDR) genomics may play a role in myocardial fibrosis. The aim of this pilot study was to determine the association between vitamin D levels, VDR polymorphisms, and biomarkers of left ventricular remodeling and hemodynamics. METHODS: In a cross-sectional pilot study, patients with ejection fraction (EF) <40% (and New York Heart Association ≥ II) undergoing right heart catheterization were included in the study. Blood was collected for determination of 25-hydroxyvitamin D level (antibody competitive immunoassay), VDR genotypes (BsmI, ApaI, TaqI, and FokI), and biomarkers (N-terminal propeptide of collagen type III [PIIINP], matrix metalloproteinase 2, and galectin 3). The vitamin D genotypes were determined through the use of pyrosequencing. RESULTS: A total of 30 patients with a mean EF of 17% ± 8% were enrolled. There was a significant association between the BsmI C allele, ApaI G allele, and TaqI A allele, which formed a haplotype block (CGA) for analysis. There were no differences in baseline parameters between patients with the VDR haplotype block (n = 20) and those without (n = 10). Individual genotypes were not associated with any biomarker or hemodynamics. Patients with the CGA haplotype demonstrated significantly higher log PIIINP values (1.74 ± 0.32 mcg/mL vs 1.36 ± 0.31 mcg/mL, P = .0041). When evaluating vitamin D levels below and above the median level (19 ng/mL), there was no significant difference between these 2 groups in regard to biomarker levels for left ventricular remodeling. CONCLUSION: This study has shown that a biomarker for collagen type III synthesis, PIIINP, was associated with the CGA haplotype of BsmI, ApaI, and TaqI single nucleotide polymorphisms on the VDR. These findings suggest that VDR genetics may play a role in myocardial fibrosis in patients with systolic heart failure.

Short- and long-term survival of patients transferred to a tertiary care center on temporary extracorporeal circulatory support.

BACKGROUND: Mechanical circulatory support (MCS) with temporary, extracorporeal assist devices restores hemodynamics in patients with refractory cardiogenic shock. These devices are frequently used in community hospitals, with subsequent referral to tertiary care centers. We sought to determine the outcomes of such referrals and identify prognostic variables that may influence management decisions. METHODS: We performed a single-institution retrospective review of 59 consecutive patients transferred on temporary, extracorporeal MCS from 1997 to 2008. Demographics, medical history, laboratory data, and clinical status were obtained, with survival determined from the medical record and the Social Security Death Index. Univariable and multivariable analysis were performed and survival estimates were determined using the Kaplan-Meier method. RESULTS: Median age was 49.6 years (range, 14 to 77 years). Forty-five patients (76%) were supported for postcardiotomy failure, and 34 (58%) required biventricular support. Twenty-five (42%) survived to hospital discharge, 11 after cardiac recovery (44%), 9 with long-term implantable MCS devices (39%), and 5 after heart transplantation (22%). Eight patients discharged with implantable MCS devices underwent heart transplantation and 1 remains alive on long-term implantable MCS support. Survival was 42% +/- 6% at 1 year and 38% +/- 6% at 5 years. Age and renal function were independent predictors of death. CONCLUSIONS: Nearly half of all patients transferred on temporary extracorporeal MCS survive to discharge. Most of the long-term survivors received a heart transplant. Age and renal function were independent predictors of death, suggesting that survival is maximized by considering eligibility for cardiac transplantation.