Clinical experience with nisoldipine in patients with atrio-ventricular blocks

The effect of the 1,4-dihydropyridine calcium antagonist nisoldipine (Bay k 5552) on the atrio-ventricular (AV) conduction was studied in 9 patients with AV blocks. The impuls propagation through the AV node (A-H time) and the bundle of His (H-V time) was determined before, 1-3 min and 10-15 min after the intravenous injection of nisoldipine (1.5 micrograms/kg body weight). Except for one patient, A-H and H-V times almost remained unaffected by the calcium antagonist. In this patient with an AV block II, Mobitz type I, A-H time transiently increased from 290 to 410 ms. Nisoldipine did not aggravate an AV block I or II to an AV block II or III, respectively. Furthermore, ventricular heart rates did not change significantly. It is concluded that, in general, nisoldipine does not impair the impulse propagation of the AV node in patients with AV blocks although a transient increase of the A-H time may occur.