The evaluation and causes of exertional dyspnea, in a pulmonary disease clinic, were recently described by Pratter et al. In this study, 85 patients were initially evaluated by history, examination, and chest roentgenogram. The physicians diagnostic impression turned out to be correct as to the cause of dyspnea in 66 percent of patients, and was most often accurate (81 percent) when the cause was asthma, COPD, interstitial lung disease, or cardiomyopathy. The authors were impressed that studies ordered during the initial visit had high negative predictive value for ruling out certain disorders but low positive predictive value. flovent inhaler
They concluded that “the cause of chronic dyspnea is determined more accurately by using objective test results combined with clinical impression compared with clinical impression alone.” Of interest, only 15 patients underwent “comprehensive metabolic exercise testing” as part of their workup, but these tests had 93 percent positive predictive value for “all diagnoses.” The authors concluded that exercise testing had known value for distinguishing respiratory from cardiovascular causes of dyspnea, and had further value in diagnosing dyspnea resulting from psychogenic causes or from deconditioning.