Aim: To retrospectively analyze the efficacy and safety of sildenafil (Sf) in patients with systemic sclerosis (SS).
Subjects and results: Sf was used in 16 patients (including 14 women) aged 20-66 years (mean 48.6 +/- 14.6 years; median 51.5 years) with SS of a duration of 2 months to 27 years (mean 8.8 +/- 7.3 years; median 6.5 years). The indications for Sf treatment were significant Raynaud's phenomenon (RP) in 3 patients, digital ulcers (DU) and/or necroses (N) in 9, pulmonary hypertension (PH) in 5 (2 patients had PH concurrent with DU/N), and critical ischemia of the left fingers in 1 patient. RP was seen in all the patients and so the effect of Sf on the course of RP was evaluated in the whole patient group.
Results: There was a significant decrease in the frequency and intensity of Raynaud's attacks in 11 (73%) of the 15 patients treated with Sf. This effect was obvious just in the first days of Sf treatment and remained stable throughout the treatment. No RP changes were seen in 3 patients. All 7 patients with DUs showed a decrease in their sizes just within the first two weeks of treatment. Complete DU healing was observed within 4-12 weeks of treatment. During a month, the necrotic area reduced and the signs of reparation appeared in 4 of the 6 patients. Pain ceased just within the first 5-7 days of treatment. Sf resulted in a rapid reduction in systolic pulmonary artery pressure (sPAP); in one case the latter diminished from 60 to 40 mm Hg just 90 min after the first intake of Sf 50 mg and remained unchanged during all 6 months during which the female patient was taking the drug. Doppler echocardiography showed that sPAP decreased from 103 to 85 mm Hg in another female taking Sf 100 mg for a month. The two cases showed clinical improvement as alleviated dyspnea and increased physical activity. In another case, Sf was discontinued because of dizziness after its first intake in a dose of 12.5 mg. The initial drug intake of the drug was not followed by adverse reactions in 12 (75%) of the 16 patients. Four patients had Sf-induced complaints, including headache (1), dizziness (2), and more severe angina pectoris (1). In different periods after treatment initiation, four more patients developed complications, such as fatal myocardial infarction after 6-week treatment, atrial fibrillation at 8 weeks, more severe angina at 6 months, and congestive heart failure after 5-year treatment. These complications were observed in patients with severe ECG changes, such as myocardial focal fibrosis or blood supply impairment.
Conclusion: Sf is an effective drug to treat the manifestations of scleroderma vasculopathy, such as RP, DU/N, and PH. Sf is well tolerated in most cases. The SS patients with pronounced ECG changes have an increased risk of severe cardiac events and they need careful ECG monitoring.