Short- and Long-Term Outcomes of Pericarditis, Myocarditis, and Myopericarditis in Patients With Malignancy on Immune...

Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment but carry a risk of immune-related adverse events, reported in 15% to 90% of the patients. ICI-associated pericardial and myocardial disease has been increasingly recognized, yet data on outcomes remain limited. We aimed to use a large real-world database to investigate the short- and long-term outcomes of ICI-associated pericarditis, myocarditis, and myopericarditis versus the non-ICI cases.

We conducted a retrospective analysis using the TriNetX database to identify patients >18 years old on ICI and diagnosed with pericarditis, myocarditis, or myopericarditis within 1 year of initiation of therapy. The primary outcome assessed was all-cause mortality, tamponade, constrictive pericarditis, and need for pericardiocentesis at 90-day, 1-year, and 5-year follow-up.

A total of 3661, 226, and 46 patients were identified in matched cohorts of ICI-induced pericarditis, myocarditis, and myopericarditis, respectively. One- and 5-year mortality was greater for pericarditis (44.3% versus 37.3%; 54.3% versus 46.9%), myocarditis (38.9% versus 20.8%; 47.8% versus 34.3%), and myopericarditis (56.5% versus 28.3%; 63.0% versus 28.3%; all P≤0.002). A multivariable Cox model showed increased ICI-related mortality for pericarditis 1-year hazard ratio [HR], 1.20 (95% CI, 1.12-1.29), 5-year HR, 1.26 (95% CI, 1.18-1.35), myocarditis 90-day HR, 1.82 (95% CI, 1.21-2.73), 1-year HR, 2.04 (95% CI, 1.43-2.91), 5-year HR, 1.64 (95% CI, 1.26-2.61), and myopericarditis 1-year HR, 2.24 (95% CI, 1.15-4.37), and 5-year HR, 2.78 (95% CI, 1.44-5.36), all with P<0.001.

Among 3661, 226, and 46 patients with ICI-associated pericarditis, myocarditis, and myopericarditis, respectively, we demonstrated an increased risk of all-cause mortality as compared with the respective non-ICI population.