Short‐term and chronic effects of transdermal nitroglycerin in stable angina pectoris

Thirty‐five patients with stable angina pectoris (AHA functional class II or III) entered a 5‐week short‐term study to determine the efficacy and safety of a transdermal therapeutic system of nitroglycerin (TDN; 5 to 20 mg/day). Nineteen of these patients were available for a final reassessment in a long‐term follow‐up after at least 1 year of continuous therapy; hence, total treatment time exceeded 8,400 patient‐days. The therapeutic efficacy of TDN was determined from weekly patient diaries of angina frequency, as well as the clinical assessment of functional class according to the criteria of the American Heart Association. Frequency of angina was reduced from ten to less than three attacks per week in all treatment groups, irrespective of angina severity at the outset, and reduction in anginal frequency was statistically significant (P <0.05) in the 10‐, 15‐, and 20‐mg dosage groups. Sixteen of the 19 patients (84%) who entered the long‐term follow‐up required no change in dosage, and all 19 patients showed improvement in AHA function class at the final reassessment. Our study showed that TDN exerted a sustained, clinically significant therapeutic benefit during both a short‐term study and long‐term follow‐up in patients with stable angina pectoris.