Prophylactic effect of intravenous tiapamil on methylergometrine-induced coronary artery spasm in patients with variant angina: randomized double-blind trial

Comparative effects of oral molsidomine and nifedipine on methylergometrine-induced coronary artery spasm

Twelve consecutive patients (10 men and 2 women, mean +/- standard deviation age 49 +/- 9 years) with chest pain, angiographically normal coronary arteries and coronary artery spasm documented by methylergometrine testing received a single oral dose of molsidomine (4 mg) or nifedipine (10 mg) in a randomized, double-blind, crossover fashion at a 24-hour interval. Coronary artery spasm was documented during coronary angiography in 6 patients (left anterior descending artery, 3; right coronary artery, 2; left circumflex, 1). In the remaining 6 patients, coronary artery spasm was documented by a positive methylergometrine test performed at the bedside, which provoked ST-segment elevation in the inferior (n = 3), anterior (n = 1) or lateral (n = 2) leads. Ninety minutes after administration of the study medication, methylergometrine testing was performed at the bedside, using incremental doses of up to 0.4 mg of methylergometrine. After molsidomine, 10 patients (83%) had a negative and 2 had a positive test; after nifedipine, 9 patients (75%) had a negative and 3 a positive test. Only 1 patient had a methylergometrine test that remained positive after either molsidomine or nifedipine. Therefore, molsidomine appears as effective as nifedipine in suppressing methylergometrine-induced coronary artery spasm in patients with variant angina. In addition, patients not responding to 1 of the study medications may respond to the other.

Comparative pharmacokinetics and cardiovascular effects of tiapamil in healthy volunteers and patients with hepatic cirrhosis

Tiapamil 70 mg was administered i.v. to 8 healthy male volunteers and 8 patients (7 males, 1 female) with biopsy proven hepatic cirrhosis. Two of the patients also received 600 mg p.o. Serial plasma and urine samples were collected and the parent drug in plasma and urine and desmethyl-tiapamil in urine were assayed by a specific HPLC method. The plasma and urine data for the parent drug after i.v. and p.o. dosing were simultaneously fitted to linear p.o. and i.v. two compartment models with exit from and input into the central compartment. Absorption was assumed to be a first order process. In the volunteers the mean pharmacokinetic parameters were: 101 l for the steady-state volume of distribution 750 ml X min-1 for nonrenal clearance, 195 ml X min-1 for renal clearance and 1.7 h for the half-life of the terminal disposition phase. The urinary recoveries of the parent drug and desmethyltiapamil averaged 21.4 and 0.8% of the dose, respectively. In the patients the steady-state volume of distribution, the amount of unchanged drug in urine and the half-life of the terminal disposition phase were significantly increased (171 l, 29.0% of the dose, 3.5 h, respectively). Decreased plasma protein binding in the patients accounted for the larger steady-state volume of distribution. The nonrenal clearance of 519 ml X min-1, tended to be smaller in the patients than in the volunteers. Together with the increased urinary recovery of tiapamil in the patients this indicates a moderately impaired elimination capacity in the cirrhotics.(ABSTRACT TRUNCATED AT 250 WORDS)