[Response of the cardiovascular system to acetylcholine test in patients with bronchial asthma]

The response of cardiovascular system to acetylcholine inhalation has been studied in 10 patients with bronchial asthma in remission. With the threshold dose of the drug, i.e. at less than or equal to 20% reduction of the forced expiration volume per 1 sec, there appeared increased cardiac beating and output, elevated pressure in the pulmonary artery, ECG sings of a sharp overload in the right atrium. The shifts in the cardiac function resulted from a fall in alveolar pO2 produced by acetylcholine-related bronchial obstruction and following hypoxic vasoconstriction of the lesser circulation. The findings emphasize the need in the cardiovascular system control when performing the acetylcholine test for bronchial reactivity.