Prognostic role of cardiac power index in ambulatory patients with advanced heart failure.
BACKGROUND
Cardiac pump function is often quantified by left ventricular ejection fraction by various imaging modalities. As the heart is commonly conceptualized as a hydraulic pump, cardiac power describes the hydraulic function of the heart. We aim to describe the prognostic value of resting cardiac power index (CPI) in ambulatory patients with advanced heart failure.


RESULTS
We calculated CPI in 495 sequential ambulatory patients with advanced heart failure who underwent invasive haemodynamic assessment with longitudinal follow-up of adverse outcomes (all-cause mortality, cardiac transplantation, or ventricular assist device placement). The median CPI was 0.44 W/m(2) (interquartile range 0.37, 0.52). Over a median of 3.3 years, there were 117 deaths, 104 transplants, and 20 ventricular assist device placements in our cohort. Diminished CPI (<0.44 W/m(2) ) was associated with increased adverse outcomes [hazard ratio (HR) 2.4, 95% confidence interval (CI) 1.8-3.1, P < 0.0001). The prognostic value of CPI remained significant after adjustment for age, gender, pulmonary capillary wedge pressure, cardiac index, pulmonary vascular resistance, left ventricular ejection fraction, and creatinine [HR 1.5, 95% CI 1.03-2.3, P = 0.04). Furthermore, CPI can risk stratify independently of peak oxygen consumption (HR 2.2, 95% CI 1.4-3.4, P = 0.0003).


CONCLUSIONS
Resting cardiac power index provides independent and incremental prediction in adverse outcomes beyond traditional haemodynamic and cardio-renal risk factors.
Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH, USA.
Justin L
JL
Grodin
Department of Cardiology, Ziekenhuis Oost-Limburg, Genk, Belgium and Hasselt University, Diepenbeek, Belgium.
Wilfried
W
Mullens
Department of Cardiology, Ziekenhuis Oost-Limburg, Genk, Belgium and Hasselt University, Diepenbeek, Belgium.
Matthias
M
Dupont
Department of Mathematics, Cleveland State University, Cleveland, OH, USA.
Yuping
Y
Wu
Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH, USA.
David O
DO
Taylor
Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH, USA.
Randall C
RC
Starling
Department of Cardiovascular Medicine, Heart and Vascular Institute, Cleveland Clinic, Cleveland, OH, USA.|Department for Cellular and Molecular Medicine, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Avenue, Desk J3-4, Cleveland, OH, USA.
W H Wilson
WH
Tang
D000328:Adult; D000368:Aged; D000553:Ambulatory Care; D002302:Cardiac Output / Q000502:physiology; D005260:Female; D006333:Heart Failure / Q000401:mortality / Q000503:physiopathology*; D016027:Heart Transplantation; D006353:Heart-Assist Devices; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D013318:Stroke Volume / Q000502:physiology; D018487:Ventricular Dysfunction, Left / Q000401:mortality / Q000503:physiopathology*
Cardiac power index; Heart failure; Prognosis