Case Report
Volume 8 Issue 9 - 2021
A Theoretical CPX Paradigm for Assessment of Exercise Performance in Heart Failure
Jeffrey Dwyer*
Department of Cardiology, Kaiser Permanente Medical Center, Vallejo, CA, USA
*Corresponding Author: Jeffrey Dwyer, Department of Cardiology, Kaiser Permanente Medical Center, Vallejo, CA, USA.
Received: June 05, 2021; Published: August 30, 2021


Data derived from cardiopulmonary exercise tests (CPX) provide prognostic indicators that reliably distinguish heart failure (HF) patients who may benefit from medical therapy from those who are likely to require hospital admission in the near future or advanced therapies, including implanted left-ventricular assist devices (L-VAD) and heart transplant. CPX also provides indices a patient’s progress toward an improved cardiac capacity for exercise. Currently, peakVO2 and slope-Ve/VCO2 provide the greatest prognostic power for risk-stratification of HF patients. Other CPX variables that may be affected by a dysfunctional cardiovascular system, resulting in a disparity between oxygen delivery and oxygen demand in active tissues, include PetCO2 (end-tidal PCO2) and Ve/VCO2 (ventilation equivalent for volume of CO2 eliminated). A theoretical analysis of trend-line intersections of these variables, plotted against %peakVO2 in serial CPX, was conducted that revealed a new paradigm with the potential for enhanced prognosis and tracking of progressive impairment or improvement of circulatory adaptation to the demands of exercise as HF status changes. A case history is presented that demonstrates the sensitivity and theoretical utility of this paradigm as the clinical status of a HF patient declined from NYHA I to heart transplant.


Keywords: Heart Failure; Respiratory Compensation; Cardiopulmonary Exercise Test; Ventilation; Heart Transplant; Anaerobic Threshold


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Citation: Jeffrey Dwyer. “A Theoretical CPX Paradigm for Assessment of Exercise Performance in Heart Failure”. EC Cardiology 8.9 (2021): 35-45.

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