Impact of Integrative Cardiopulmonary Exercise Testing (25)
Pulmonary vascular disease: Chronic disorders of the pulmonary vasculature are notoriously difficult to diagnose early, especially when the patient s symptoms are attributed to other kinds of lung or heart disease. Frequently ordered tests may be either insensitive or nonspecific, such as radionuclide perfusion scans, or invasive and unsuitable for screening, such as contrast pulmonary arteriograms. Exertional dyspnea is often the presenting complaint, with abnormally low exercise cardiac output and arterial hypoxemia at the time of diagnosis. Thus, there may be findings of both cardiovascular limitation and pulmonary limitation during integrative cardiopulmonary exercise testing. proventil inhaler
After diagnosis, exercise testing may be used to assess the severity of pulmonary vascular disease. Janicki et al showed that maximum Vo2 in response to exercise was lower in those patients with higher pulmonary vascular resistance and lower cardiac index. Marked elevation of mixed venous blood lactate was found, reflecting severe reduction in cardiac output at inappropriately low work rates. D’Alonzo and colleagues studied 11 patients with primary pulmonary hypertension with integrative cardiopulmonary exercise testing. No respiratory impairment was observed, but again, cardiovascular limitation was noted with low AT, low maximum Vo2, and low oxygen-pulse.