A base rate is not a threshold
Educational use only. Not clinically reviewed63-year-old man for calm interval recording, rhythm monitoring, joint escalation, and handoff practice. About 9 simulated minutes.
What you will practise
- Record the exposure interval as part of the finding.
- Record what is present that does not sound cardiac.
- Arrange continuous rhythm monitoring, and say why.
- Escalate to both teams rather than one.
- Refuse rarity as a reason not to look.
- Review the boundaries and their certainty.
- Hand off a problem neither team owns alone.
Review and sources
Not clinically reviewed. No clinician has signed this scenario.
- Fan Y, Xu Y, Liu X, Liu G. Immune checkpoint inhibitor-related myocarditis: a comprehensive analysis of clinical manifestations and prognostic factors. Oncologist. 2025;30(10). Multicentre retrospective study of 161 patients with biopsy-proven or clinically diagnosed ICI-myocarditis. Onset a median of 4 weeks after initiation, at a median of the second cycle, with mortality occurring mainly within 60 days. Reported incidence 0.1% to 1% in clinical trials, higher with combination regimens; historical mortality quoted at 30% to 50%. Predictors of cardiotoxicity-related death included initial left ventricular ejection fraction below 50%, alanine aminotransferase, creatine kinase-MB, and concomitant ICI-myositis.
- Wang DY, Salem JE, Cohen JV, et al. Fatal Toxic Effects Associated With Immune Checkpoint Inhibitors: A Systematic Review and Meta-analysis. JAMA Oncol. 2018;4(12):1721-1728. Myocarditis had the highest fatality rate of any checkpoint-inhibitor toxicity reported, at 52 (39.7%) of 131 reported cases, against 2% to 5% for colitis and endocrine events.
Open Sim Lab is an educational simulator, not for clinical use. It is not a clinical decision-support tool, not a dosing calculator, and is not validated for any decision affecting a real patient.