Combining Nifedipine with Atenolol for Angina Pectoris

Oral nifedipine can be used safely where left ventricular function is normal The haemodynamic and electro physiological effects of nifedipine given IV (7.5 J,tg/kg) and then orally (30

mg/day for 3 days and then 60 mg/day), were studied in 9 patients with angina pectoris and normal ventricular function who showed adequate {3-blockade by atenolol (reduction in maximal heart rate over 25%). IV nifedipine produced a transient fall in the left ventricular systolic BP (117 to 110mm Hg at 10 min) and peak positive dP/dt (1366 to 1267mm Hg/sec at 10 min), both values returning to control levels at 20 min. Atrioventricular nodal conduction time and sinus rate were unchanged. There was also a transient depression in atrioventricular nodal function but this was detected only when sensitive tests were used .

In patients taking the oral combination of nifedipine and atenolol, resting BP and heart rate were unchanged with no prolongation of PR interval. The reductions in systolic BP and rate pressure product seen with atenolol at peak exercise were not enhanced by nifedipine. Radionuclide angiography demonstrated no change in the ejection fraction following oral nifedipine but a significant increase in peak ejection rate compared with atenolol alone. The results indicate that patients with normal atrioventricular nodal function will not be adversely affected by the combination of nifedipine and atenolol. Rowland, E. e/ al.: British Hearl Journal 50: 383 (Ocl 1983)

16 INPHARMA ® 14 Jan 1983 0156-2703/83/0114-0016/0$01 .00/0 © ADIS Press