[Hemodynamic effects of percutaneous trinitrin].

The haemodynamic effects of nitroglycerin (NG) ointment were studied in 13 patients, 6 with congestive cardiac failure. After two basal measurements 30 minutes apart, heart rate (HR), right atrial pressure (RAP), pulmonary artery diastolic pressure (PADP), mean systemic arterial pressure (MAP) and cardiac index (CI) were measured every fifteen minutes for one hour, and every hour for five hours. Two patients were given one capsule, and nine patients two capsules of 10 mg NG, applied on separate 15 cm2 skin patches and covered with plastic dressings. There was a slight fall of 1,9% in HR from the 45th minute to the 5th hour. A large increase in HR was only observed in one patient who had low basal filling pressures. A moderate decrease in MAP was recorded (4,6%, p less than 0,05) The greatest changes were observed in RAP which decreased (p less than 0,05) from the 30th to the 60th minute with a maximum at the 45th minute (17,4%) and in PADP which fell from the 15th minute to the 5th hour (p less than 0,005) with a maximum at the 120th minute (21,9%). Local tolerance was good. The systolic blood pressure did not fall below 90 mm Hg in any patient. A case by case analysis showed falls of RAP and PADP of over 20% in 10 and 9 patients respectively. The decrease in PADP was not proportional to the basal value but patients with the highest initial values had the least changes. A 20% fall in PADP was observed in only one of four patients with PADP of over 25 mm Hg at rest. A greater dose of NG might have had a greater effect in these patients. There was no significant change in CI, probably due to the stability of peripheral arterial resistances during the study. The value of this preparation of NG lies in its long duration of action. A fall in PADP of over 15% was observed up to the 150th minute, and persisted to a lesser degree up to the 5th hour. This makes it very suitable for the treatment of nocturnal angina as conventional antianginal delayed release nitrate derivatives usually have a shorter duration of action.