Abstract 12041: Associations Between Acylcarnitine to Total Carnitine Ratio and Adverse Prognosis in Heart Failure Patients With Reduced or Preserved Ejection Fraction

Abstract

Background: The failing heart is accompanied by disturbed energy metabolism with mitochondrial dysfunction. This metabolic change involves altered fatty acid metabolism. Carnitine is an essential cofactor for fatty acid oxidative metabolism, which is the predominant source of ATP in the normal aerobic condition. Decreased myocardial carnitine levels and increased plasma carnitine levels in heart failure (HF) have been reported. A plasma acylcarnitine to total carnitine ratio (AC/TC ratio) has been recently recognized as a marker of carnitine deficiency. We aimed to investigate the significance of the AC/TC ratio on prognosis of HF and compare its prognostic impact between HF patient with reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF). Methods and Results: We analyzed 168 patients with HF who admitted to our hospital. These patients were divided into 3 groups based on the AC/TC ratio: 1 st (AC/TC ratio <0.15, n = 56), 2 nd (0.15≤ AC/TC ratio <0.25, n = 56) and 3 rd (0.25≤ AC/TC ratio, n = 56) tertiles. In the average follow-up of 1004 days, 23 cardiac deaths and 28 re-hospitalizations from worsening heart failure occurred. In the Kaplan-Meier analysis, cardiac event rates progressively increased from 1 st to 2 nd and 3 rd groups (21.4%, 26.8% and 42.9%, P = 0.022). In the Cox proportional hazard analysis, the AC/TC ratio was an independent predictor of cardiac event after adjusting for confounding factors (HR 1.33, 95% CI 1.01-1.74, P = 0.044). When analyzed separately between HFpEF (n = 66) and HFrEF (n = 168), the Kaplan-Meier analysis revealed that cardiac event rates progressively increased from 1 st to 2 nd and 3 rd groups in HFpEF (P = 0.008), but not in HFrEF (P = 0.321). In the Cox proportional hazard analysis, the AC/TC ratio was an independent predictor of cardiac event in HFpEF (HR 2.00, 95% CI 1.09-3.67, P = 0.025), but not in HFrEF (HR 1.27, 95% CI 0.95-1.70, P = 0.101). Conclusion: The AC/TC ratio can identify high risk HF patients, especially in HFpEF.