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Published on: September 6, 2024
The ventilatory classification system effectively predicts hospitalization in patients with heart failure
Ross Arena1, Jonathan Myers, Joshua Abella
1Department of Physical Therapy, Physiology, and Internal Medicine, Virginia Commonwealth University, Health Sciences Campus, Richmond, VA 23298, USA. raarena@vcu.edu
Introduction:
The minute ventilation carbon dioxide production (VE/VCO2) slope is a consistent and robust prognostic marker in the heart failure (HF) population. The purpose of this study was to assess the ability of the newly developed ventilatory classification system, a powerful predictor of major cardiac events (mortality, transplantation, and left ventricular assist device implantation), to identify varying degrees of risk for cardiac-related hospitalization.
Methods:
A total of 459 patients with chronic HF who underwent cardiopulmonary exercise testing were included in this analysis. The VE/VCO2 slope was determined, and participants were classified into 1 of 4 groups (ventilatory class [VC]-I: < or =29.9; VC-II: 30.0-35.9; VC-III: 36.0-44.9; and VC-IV: > or =45.0). Participants were tracked for cardiac-related hospitalization for 2 years following testing.
Results:
There were 169 cardiac-related hospitalizations during the 2-year tracking period (annual event rate = 21.6%). Decompensated HF, cardiac ischemia, and cardiac arrhythmia were the reasons for hospitalization in 83%, 11%, and 6% of the cases, respectively. Kaplan-Meier analysis revealed that the VC system was prognostically significant (log-rank = 85.2, P < .001) and superior to the Weber classification system (log-rank = 70.0, P < .001).
Discussion:
This study indicates that the VC system, based on the VE/VCO2 slope, effectively identifies patients with HF at varying degrees of risk for cardiac-related hospitalization. Furthermore, this newly developed system prognostically outperformed the established Weber classification system based on peak oxygen uptake.
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