Abstract 13111: Cardiac Determinants of Right Ventricular Pressure-Flow Response to Exercise in Heart Failure: A Non-Invasive Approach Combining Cardiopulmonary Exercise Testing and Exercise-Echocardiography
Background: The pulmonary pressure (PAP) over cardiac output (CO) exercise response has been proposed as expression of right ventricular (RV) to pulmonary circulation (PC) coupling. The functional implications and cardiac phenotype of PAP/CO slope in heart failure (HF) have never been investigated. Aim: To define the functional and cardiac characteristics related to an unfavorable RV-PC coupling in HFrEF.
Methods: 87 HFrEF patients (mean age 65±11 y, male 70%, mean LVEF 33±9%) underwent a maximal CPET (incremental ramp protocol) combined with exercise-echo. MeanPAP/CO slope is calculated as the slope between the exercise increase in mean PAP and CO.
Results: Population was divided into 2 groups according to mPAP/CO slope: Group A (n=27) slope <3.5 mmHg/L*min and B (n= 60) slope≥3.5 mmHg/L*min. Patients with abnormal response (Group B) exhibited a worse functional capacity (lower maximal workload and peak oxygen consumption) and ventilatory efficiency (steeper VE/VCO2). Group B had also worse LV remodeling and higher prevalence of dynamic severe mitral regurgitation (MR), associated with elevated pulmonary arterial pressure (systolic PAP) and an impaired rest and peak CO. The best linear regression model identified age, gender, LV EDVi and rest and peak severe MR as main cardiac determinants of mPAP/CO slope. Conclusions: In HFrEF population, an unfavorable pulmonary pressure to cardiac output exercise response, or steeper mPAP/CO slope, is associated with advanced eccentric LV remodeling and dynamic severe MR, overall resembling the most unfavorable functional phenotype.
Author Disclosures: G. Generati: None. F. Bandera: None. M. Pellegrino: None. F. Carbone: None. V. Labate: None. E. Alfonzetti: None. M. Guazzi: None.
- © 2015 by American Heart Association, Inc.