Pathophysiological mechanism of worsened clinical outcome by lowered left ventricular cardiac power output in heart failure

Autor: H Aoyagi, S Tsujinaga, H Iwano, S Ishizaka, Y Tamaki, K Motoi, Y Chiba, M Murayama, M Nakabachi, H Nishino, S Yokoyama, T Sato, S Kaga, T Nagai, T Anzai
Rok vydání: 2022
Předmět:
Zdroj: European Heart Journal - Cardiovascular Imaging. 23
ISSN: 2047-2412
2047-2404
DOI: 10.1093/ehjci/jeab289.383
Popis: Funding Acknowledgements Type of funding sources: None. Background Cardiac power output (CPO) is a measure of cardiac pumping function, and CPO during exercise is known to be a powerful prognostic marker of heart failure. Despite its prognostic significance, pathophysiological mechanism of the association between reduced CPO and worse clinical outcome is unknown. We hypothesized that reduced CPO is associated with worse outcome through the reduced exercise capacity and enhanced ventilatory response. Methods Cardiopulmonary exercise testing and exercise stress echocardiography were performed in consecutive 64 patients with chronic heart failure who admitted to our department for the management of heart failure [60 ± 14 years old, left ventricular (LV) ejection fraction 39 ± 16%, ischemic etiology 16%, brain natriuretic peptide 124 pg/ml (51-313)]. Peak oxygen uptake (peak VO2) and the lowest minute ventilation / carbon dioxide production ratio (VE/VCO2) were measured as a parameter of exercise tolerance and that of ventilatory response, respectively. LV ejection fraction was measured by disk summation method at peak exercise. By using Doppler images, E/e" at peak exercise was measured as a marker of LV filling pressure, and CPO normalized by LV mass was obtained as 0.222 × cardiac output × mean blood pressure / LV mass [W/100 g]. Cardiac events defined as hospitalization for heart failure, cardiac death, or implantation of a LV assist device after the examinations were recorded. Results CPO at rest was weakly correlated with peak VO2 (r = 0.25, p = 0.046) but not with VE/VCO2. In contrast, CPO at peak exercise was positively correlated with peak VO2 (r = 0.50, p Conclusions In patients with chronic heart failure, CPO during exercise was associated with prognosis of heart failure through the reduced exercise capacity and enhanced ventilatory response.
Databáze: OpenAIRE