The clinical efficacy of transdermal nitroglycerin patch in patients with angina has not known exactly. After the application of transdermal nitroglycerin, the influences of transdermal nitrate on exercise capacity and clinical symptom in patients with angina were compared with the clinical effects of oral nitroglycerin.

Long acting oral nitrate was administered in 20 patients (9 male, 11 female, age:56.3±4.6) and transdermal nitrate (Angiderm Patch ) applied in 20 patients (8 male, 12 female, age:53.9±9.8), who suffered from angina more than 4 attacks per week. All patients were evaluated at 4-week interval:after 2 weeks' run-in period, after 4 weeks of randomized non-titrated treatment (first visit), after 8 and 12 weeks of titrated treatment (second and third visits). The frequency of angina, side effects of headache and skin irritation, blood pressure, echocardiographic ejection fraction and exercise treadmill score were compared between the two groups.

The frequency of angina attack was 14.4±6.0 in oral nitrate and 14.0±4.9 in transdermal nitrate per two weeks during run-in period. After nitrates, the frequency of angina reduced to 8.1±4.5, 5.4±2.2 on the first, to 3.0±3.5 and 1.7±1.4 on the second, and to 1.2±1.7 and 0.3±0.4 on the third visit in oral and transdermal nitrate groups respectively. Blood pressure and ejection fraction were unchanged in both groups. Exercise treadmill score was 10.4±4.3 in oral and 10.6±2.3 in transdermal nitrate group during run-in period, which was increased to 12.6±4.0, 13.7±2.5 on the first, to 13.6±3.0, 15.1±2.2 on the second, and to 15.3±2.7, 15.6±1.9 on the third visit after oral and transdermal nitrates respectively. However, changes in the frequency of anginal episodes and exercise treadmill score were not different between two groups. Side effects of headache were observed in 7 of oral and 4 of transdermal nitrate group and skin irritation in 2 of transdermal group.

Transdermal nitroglycerin is equally effective as oral nitroglycerin in the reduction of the frequency of angina attack and the improvement of exercise tolerance without significant side effects in patients with angina.