BRONCHIAL HYPERREACTIVITY IN PATIENTS WITH MODERATE PULMONARY CIRCULATION OVERLOAD

The clinical course of congestive heart failure (CHF) and mitral valve stenosis (MVS) is accompanied by episodes of dyspnea, wheezing, and c ough, symptoms also observed in patients with bronchial hyperreactivit y. However, it is still controversial whether bronchial hyperreactivit y is demonstrable in patients with chronic overload of the pulmonary c irculation. In order to examine the effects of CHF on the respiratory function, we performed pulmonary function tests, titrated bronchial ac etylcholine provocations, and left and right heart catheterization in 21 patients with impaired left ventricular function (mean ejection fra ction, 37 percent, NYHA class 3), 5 patients with MVS, and 17 control patients with coronary artery disease (mean ejection fraction, 63 perc ent). Bronchial hyperresponsiveness was defined as an obstructive resp onse to increased doses of inhaled acetylcholine. A 20 percent fall in forced expiratory volume in the first second (FEV1), a 100 percent in crease in total airway resistance (Rtot), and a 60 percent reduction o f pulmonary conductance (SGtot) were considered positive. Patients wit h impaired left ventricular function showed significantly higher airwa y resistance, and lower airway conductance at the maximal tolerated ac etylcholine dose compared with control patients. Patients with MVS had a significant lower airway conductance. The induced bronchial obstruc tion was completely reversible upon inhalation of a beta2-mimetic. We conclude that chronic overload of the pulmonary circulation is accompa nied by bronchial hyperreactivity that may augment the symptoms of dys pnea in patients with CHF and MVS.