Chest
Clinical InvestigationsAcute Electrophysiologic Effects of Inhaled Salbutamol in Humans
Section snippets
Patient Selection
The ethics committee of our institution approved the study. This investigation conforms to the principles outlined in the Declaration of Helsinki. Signed informed written consent was obtained from all subjects before their participation in the study.
In the present study, 18 patients were enrolled. All patients had mild COPD with postbronchodilator FEV1/FVC ratio ≤ 70% and FEV1 ≥ 80% of predicted normal value, or mild persistent bronchial asthma with FEV1 ≥ 80% of the predicted normal value and
Patients
The patient population included 11 men and 7 women between 44 years and 71 years of age (mean, 57 ± 4 years). Six patients had bronchial asthma, and the remaining 12 patients had mild COPD. Nine patients also had arterial hypertension and were receiving an angiotensin-converting enzyme inhibitor drug regimen. No patients were receiving administered β-blockers. All patients were evaluated with lung function tests at the beginning of the study. All subjects had normal left ventricular function as
Discussion
Despite the widespread use of β2-agonists, their safety has been questioned. Several studies9101112131415 have reported an increased incidence of cardiac arrhythmias in patients treated with these agents, and other studies131415 found an increased cardiovascular death with the use of oral and nebulized β2-agonists.9101112131415 Although no causal relationship has been demonstrated, the possible arrhythmogenic effects of these drugs place them under considerable suspicion. Clarifying the effects
Conclusion
We have demonstrated that inhaled salbutamol results in significant changes in cardiac electrophysiologic properties. These effects seem to be due to β2-adrenergic stimulation and could explain the increased incidence of arrhythmias in some patients treated with these agents, especially in certain clinical conditions, such as heart failure. Care must be taken before extrapolating our findings to all human subjects, and further studies are required to clarify to what extent the
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