Immune Checkpoint Inhibitor Myocarditis and Left Ventricular Systolic Dysfunction.

Area of Science:

• Cardiology
• Oncology
• Immunology

Background:

• Immune checkpoint inhibitors (ICIs) have revolutionized cancer therapy.
• Immune checkpoint inhibitor myocarditis (ICI-M) is a serious, potentially fatal complication.
• Understanding predictors of reduced left ventricular ejection fraction (LVEF <50%) in ICI-M is crucial.

Purpose of the Study:

• Identify factors associated with LVEF <50% versus LVEF ≥50% at hospitalization for ICI-M.
• Evaluate the relationship between LVEF and 30-day all-cause mortality in ICI-M patients.

Main Methods:

• Retrospective analysis of the International ICI-Myocarditis Registry (n=757).
• Patients stratified by LVEF (<50% or ≥50%) on admission.
• Cox proportional hazards models and multivariable logistic regression used.

Main Results:

• 35% of patients had LVEF <50%.
• Predictors of LVEF <50% included younger age, lower BMI, chest radiation, BRAF/MEK inhibitors, pre-existing heart failure, dyspnea, and longer time from ICI initiation.
• Myositis symptoms were linked to LVEF ≥50%.

Conclusions:

• Dyspnea, time from ICI initiation, history of heart failure, and prior cardiotoxic therapy predict reduced LVEF in ICI-M.
• Reduced LVEF showed a marginal association with increased 30-day mortality.