Ivabradine Prevents Heart Rate Acceleration in Patients with Chronic Obstructive Pulmonary Disease and Coronary Heart Disease after Salbutamol Inhalation

Accelerated sinus rhythm is an important side effect of inhaled salbutamol which is especially harmful in patients with chronic obstructive pulmonary disease (COPD) and coronary heart disease (CHD). Cross-over, randomized, open label study design. 20 patients (18 males and two females) with COPD stage II-IV and comorbide CHD NYHA class I-III were included. Spirometry with 400 mg salbutamol inhalation was performed at two consecutive days of the study. Patients in group I were prescribed 5 mg ivabradine per os 3 h before salbutamol inhalation solely on the first day of the study and patients of group II received 5 mg ivabradine only on the second day of the study. Salbutamol caused a significant increase of HR by 5.5 bpm (95% CI 0.8; 10.2, p < 0.03). After ivabradine ingestion salbutamol did not change HR significantly by -2.4 bpm (-7.0; 2.3, p = 0.33). The attenuation of HR elevation by ivabradine was significant, p < 0.01. Salbutamol alone increased FEV1 by 6.0% (2.7; 9.3, p < 0.01). This effect was not impaired by ivabradine (FEV1 increase by 7.7% (2.8; 12.6, p < 0.01 versus baseline, p = 0.5 versus no ivabradine). Ivabradine 5 mg per os prevents heart rate acceleration after inhalation of 400 mg salbutamol. Ivabradine has no impact on lung function in patients with moderate-to-very-severe COPD and CHD comorbidity.