Résumé
Acute myocarditis (AM) is a rare but severe disease affecting patients of all age. Large multicentric data in children and comparison with adult are lacking.
We aim to compare AM presentation, management, and outcomes according to age of the patients at admission and to identify factors associated with 30-day prognosis.
All cases of AM were included between March 2020 and November 2021 in 64 adults and children centres in France. We collected baseline data, AM presentation and evolution, in-hospital management and in-hospital complications. All-cause death and major cardiovascular events (MACE) (acute pulmonary oedema, cardiogenic shock, or cardiac arrest) were investigated with a 30-day systematic follow-up. NCT04375748
In total, 745 AM patients (417 adults and 328 children) were included, mainly men (73.4%) with a median age of 19.8 [12.5–30.9] years old. Children had more extra-cardiac manifestations (78.3% vs. 24.0%, P<0.01), more clinical signs of heart failure (14.9% vs. 7.0%, P<0.01) and shock (47.9% vs. 12.7%, P<0.01). They also had lower left and right ventricular function on TTE. The main aetiology of AM was viral myocarditis (32.6% of the overall population) with a predominance in adults (50 vs. 20% in children). Children had less toxic myocarditis (0 vs. 2.6%, P<0.01), immunologic myocarditis (1.0 vs. 7.0%, P<0.01), vaccine-related myocarditis (5.0 vs. 9.0%, P<0.01) and idiopathic AM (9.0 vs. 28.0%, P<0.01). Multisystem inflammatory syndrome was predominant in children (66.0 vs. 1.0%, P<0.01). Cardiac treatments as beta blockers (84.4 vs. 33.4%, P<0.01) or ACE/ARB2 (63.1 vs. 37.3%, P<0.01) were significantly more often used in adults. On the contrary, corticosteroids (68.3 vs. 14.3%, P<0.01) and immunomodulators including antiviral and/or IGIV were significantly more used in children (65.1 vs. 4.5%, P<0.01). In-hospital complications occurred more in children (23.8 vs. 14.3, P<0.01) especially acute kidney injury (11.0 vs. 5.3%, P<0.01) and cardiogenic shock (15.2 vs. 8.1%, P<0.01). At 30-day, adults presented more composite endpoint including death, cardiac arrest, cardiogenic shock, and acute pulmonary oedema (3.4 vs. 0.9% respectively in adults and children, P<0.03)
AM presentation, aetiologies and management differs according to age. Despite higher rate of in-hospital complications in children, the 30-day prognosis is worse in adult.