Intracardiac energy inefficiency during decompensated and compensated heart failure.

Aims: The mechanisms underlying the acute decompensation of heart failure (HF) remain unclear. The present study examined intracardiac dynamics during decompensated HF using echo-vector flow mapping.

Methods and results: Fifty patients admitted for decompensated HF were prospectively enrolled, and intracardiac energy loss (EL) was assessed by echo-vector flow mapping at admission (decompensated HF) and discharge (compensated HF). Outcome measures were average EL in the left ventricle (LV) in decompensated and compensated HF and were compared with those in 40 stable non-HF patients with cardiovascular diseases. The mean age of HF patients was 80.8 ± 12.4 years. The prevalence of both females and atrial fibrillation was 48.0%. The prevalence of HF with a reduced ejection fraction (<40%) (HFrEF) was 34.0%. The prevalence of decompensated HF classified into clinical scenario 1 was 33.3%. Blood pressure and NT-proBNP were significantly higher in decompensated HF than in compensated HF, while the ejection fraction (EF) was significantly lower. Average EL was significantly higher in compensated HF patients than in non-HF patients (40 mW/m·L vs. 26 mW/m·L, P = 0.047). A multivariable analysis identified age, systolic blood pressure, LVEF, and the absence of chronic obstructive pulmonary disease as independent risk factors for high LV-EL regardless of the presence of HF. Furthermore, average EL in HF patients was significantly higher under acute decompensated conditions than under compensated conditions (55 mE/m·L vs. 40 mE/m·L, [+18 mE/m·L, P = 0.03]). Higher EL under decompensated HF conditions was significant in non-HFrEF (+19 mW/m·L, P = 0.009) and clinical scenario 1 (+23 mW/m·L, P = 0.008). The multivariable analysis identified eGFR as an independent risk factor for a decrease in average LV-EL under decompensated conditions.

Conclusions: Energy inefficiency in LV was apparent even in stable HF patients and significant under acute decompensated conditions, particularly in HF with preserved EF and clinical scenario 1.