PURPOSE: Exercise limitation as determined by Cardio-Pulmonary Execise Testing (CPET)is a reliable but typically non-specific finding that requires further evaluation. While respiratory etiologes are generally apparent (through imaging, PFT studies), cardio-vascular limitations involve numerous diverse causes requiring an often difficult workup. To aid the physician in structuring a selective search, the present study was performed.
METHODS: CPET data were reviewed on 126 referred individuals of whom, 76 (44F, 32M) exhibited reduced work capacity (WC < 85% V02 max predicted) with principally cardio-vascular limitation (CVL). These were selected for further analysis. In each, results of follow-up testing (cardiac-stress testing, echo-cardiograms, CBC, cardiac catheterization) were reviewed. Results were categorized as: Cardiac dysfunction due to hypertension (HHD), ischemia (IHD), valvular disease (VHD). Primary pulmonary hypertension (PPH); peripheral vascular disease (PVD); anemia (An); other - (O) including conditioning, myopathy and inconclusive etiologies.
RESULTS: Of the 44F, the following were determined: 21 - HHD (48%); 8 - IHD (18%); 3 - VHD (6.8%); 2 - PPH (4.5%); 1 - An (2.3%); 9 - O (20%). The 32M individuals were characterized as follows: 10 - HHD (31%); 12 - IHD (37%); 3 - VHD (9.3%); 0 - PPH (0%); 1 - An (3.1%); 6 - O (19%).
CONCLUSION: Female subjects who exhibited reduced work capacity due to cardio-vascular limitation distinguished themselves from male counterparts by higher incidence of hypertensive LV dysfunction and primary pulmonary hypertension; and a lower incidence of ischemic etiologies. Incidentally, obesity was noted to be a marker for females with HHD. Deconditioning appears to limit exercise capacity in both groups equally. Whether our urban setting with its higher prevalence of hypertension limits the applicability of these results to other settings is currently uncertain; and may be clarified by further study.
CLINICAL IMPLICATIONS: The evaluation of CVL exertional dyspnea is often costly and difficult to design due to the many potential causes. The present study suggests that gender be considered along with historical and exam based clues in constructing a cost-effective and ultimately successful diagnostic workup.
DISCLOSURE: Owais Khawaja, No Financial Disclosure Information; No Product/Research Disclosure Information