448 ACUTE IDIOPATHIC PERICARDITIS: THE IMPORTANCE OF GUIDELINE-BASED TREATMENT TO AVOID RECURRENCE. (15th December 2022) - Giordani, Andrea Silvio
Abstract: Background: Acute pericarditis usually resolves with first-line treatment, but it may recur. Recurrences are usually attributed to a deranged immunity, but it is unclear whether they may also be related to inappropriate treatment. Purpose: The aims of our study were to clarify the potential role of inappropriate treatment on relapse episodes in acute pericarditis. Methods: Consecutive patients prospectively followed-up for over 20 years at Padua University Cardioimmunology outpatient clinic were included. Clinical and instrumental findings were recorded at diagnosis and at each follow-up. Spectrum, appropriateness, efficacy and side effects of therapies received by patients before and after referral to our centre were considered. The distribution of recurrence-free survival probability has been estimated using Kaplan-Meier method; impact of the covariates of interest on the outcome was assessed using Cox univariate analysis models. Results: The cohort consisted of 144 patients (82 males, 62 females, mean age 50 years, 143 Caucasian and 1 African), 139 had acute pericarditis, which was recurrent in 63; 5 had constrictive pericarditis; aetiology was idiopathic/presumed-viral in 112, bacterial in 1, secondary to pericardial injury in 26, to Dressler syndrome in 2, and to a systemic immune-mediated disease in 3. At diagnosis, 68% were in NYHA class I, 22% in II, 5% in III, 5% in IV; 9% developed cardiac tamponade; 84% patients received non-steroidal-anti-inflammatory drugs, 54% colchicine and 19% corticosteroids. Treatment was not in line with ESC guidelines in 31% of patients for non-steroidal-anti-inflammatory drugs, in 12% for steroids and in 28% for colchicine, requiring readjustment. Patients with constrictive pericarditis underwent uncomplicated pericardiectomy. No patient was dead at last follow-up. Estimated recurrence-free-survival probability was 86% at 1st year, 58% at 5 th, 52% at 10th. Variables which tended to be associated with a higher risk of recurrence were: cardiac tamponade at diagnosis, left heart failure, concomitant immuno-mediated diseases, specific etiology, history of recurrence, inappropriate treatment with colchicine, inappropriate treatment with non-steroidal anti-inflammatory-drugs, III or IV NYHA class at diagnosis. Treatment of acute/recurrent forms before referral did not appear in line with the international recommendations in terms of daily dosage and duration, or both, in 43 patients for anti-inflammatory drugs, in 17 for corticosteroids and in 39 for colchicine, which was omitted despite the absence of known contraindications (see attached Table). Following treatment adjustment to international guidelines, 107 patients with relapsing pericarditis obtained complete remission; only 13 (9%) of our AP patients showed a truly treatment-refractory form that required a second-line therapy. All patients (5) with constrictive pericarditis underwent uncomplicated pericardiectomy. Conclusion: When treated according to international guidelines, pericarditis has usually a favourable evolution, even in its most adverse presentations. Treatment inaccuracies seems to account, at least in part, to disease recurrences.