Table 1.

Potential factors associated with a poor prognosis in immune checkpoint inhibitor–associated myocarditis

Clinical factors

Pre-existing cardiovascular disease ICI combination Early first symptoms/signs after ICI initiation Cardiac arrest Heart failure and cardiogenic shock Oxygen dependence Low diastolic blood pressure Simultaneous non-cardiovascular irAE, especially myositis and myasthenia gravis

Electrocardiogram

Severe conduction disorders and ventricular arrhythmias QRS ≥ 100 ms Decrease in QRS voltage

Echocardiography

Low |GLS| in echocardiography ­ |GLS| < 13% if LVEF <50% ­ |GLS| < 16% if LVEF ≥50%

Cardiac magnetic resonance imaging

Myocardial native T1 value on CMR T1 >mean value ±2 standard deviations of the site norm Septal LGE on CMR

Serum biomarkers

Troponin ­ High Troponin T values at admission/peak/discharge ­ Discharge Troponin T value ≥1.5 ng/mL ­ Admission Troponin I value ≥3.73 ng/mL Absolute lymphocyte count decrease ≥35% to admission Neutrophil/lymphocyte ratio increase ≥100% to admission

Endomyocardial biopsy

Degree of lymphocyte infiltration on EMB ­ >50 CD3+ cells/high-power field

Management

Delay in initiation of high-dose corticosteroids Requirement of intensified immunosuppressive therapy

CMR, cardiac magnetic resonance; EMB, endomyocardial biopsy; ICI, immune checkpoint inhibitor; irAE, immune-related adverse event; |GLS|, global longitudinal strain absolute value; LGE, late gadolinium enhancement; LVEF, left ventricular ejection fraction.