Search

Importance: Acute myocarditis, defined as a sudden inflammatory injury to the myocardium, affects approximately 4 to 14 people per 100 000 each year globally and is associated with a mortality rate of approximately 1% to 7%., Observations: The most common causes of myocarditis are viruses, such as influenza and coronavirus; systemic autoimmune disorders, such as systemic lupus erythematosus; drugs, such as immune checkpoint inhibitors; and vaccines, including smallpox and mRNA COVID-19 vaccines. Approximately 82% to 95% of adult patients with acute myocarditis present with chest pain, while 19% to 49% present with dyspnea, and 5% to 7% with syncope. The diagnosis of myocarditis can be suggested by presenting symptoms, elevated biomarkers such as troponins, electrocardiographic changes of ST segments, and echocardiographic wall motion abnormalities or wall thickening. Cardiac magnetic resonance imaging or endomyocardial biopsy are required for definitive diagnosis. Treatment depends on acuity, severity, clinical presentation, and etiology. Approximately 75% of patients admitted with myocarditis have an uncomplicated course, with a mortality rate of approximately 0%. In contrast, acute myocarditis that is complicated by acute heart failure or ventricular arrhythmias is associated with a 12% rate of either in-hospital mortality or need for heart transplant. Approximately 2% to 9% of patients have hemodynamic instability, characterized by inability to maintain adequate end-organ perfusion, and require inotropic agents, or mechanical circulatory devices, such as extracorporeal life support, to facilitate functional recovery. These patients have an approximately 28% rate of mortality or heart transplant at 60 days. Immunosuppression (eg, corticosteroids) is appropriate for patients who have myocarditis characterized by eosinophilic or giant cell myocardial infiltrations or due to systemic autoimmune disorders. However, the specific immune cells that should be targeted to improve outcomes in patients with myocarditis remain unclear., Conclusions and Relevance: Acute myocarditis affects approximately 4 to 14 per 100 000 people per year. First-line therapy depends on acuity, severity, clinical presentation, and etiology and includes supportive care. While corticosteroids are often used for specific forms of myocarditis (eg, eosinophilic or giant cell infiltrations), this practice is based on anecdotal evidence, and randomized clinical trials of optimal therapeutic interventions for acute myocarditis are needed.

Importance: In the last decade, immune checkpoint inhibitors (ICIs) have been approved for the treatment of many cancer types. Immune checkpoint inhibitor-associated myocarditis has emerged as a significant and potentially fatal adverse effect. Recognizing, diagnosing, and treating ICI-associated myocarditis poses new challenges for the practicing clinician. Here, the current literature on ICI-associated myocarditis is reviewed., Observations: Clinical presentation and cardiac pathological findings are highly variable in patients with ICI-associated myocarditis. Although endomyocardial biopsy is the criterion standard diagnostic test, a combination of clinical suspicion, cardiac biomarkers (specifically troponin), and cardiac imaging, in addition to biopsy, is often needed to support the diagnosis. Importantly, the combination of a cytotoxic T-lymphocyte-associated protein 4 inhibitor with a programmed cell death protein 1 or programmed death-ligand 1 inhibitor increases the risk of developing ICI-associated myocarditis., Conclusion and Relevance: This review aims to provide a standardized diagnostic and therapeutic approach for patients with suspected ICI-associated myocarditis. A complete history of recent cancer treatments and physical examination in combination with cardiac biomarkers, cardiac imaging, and endomyocardial biopsy represent a pragmatic diagnostic approach for most cases of ICI-associated myocarditis. The addition of novel biomarkers or imaging modalities is an area of active research and should be evaluated in larger cohorts.

Importance: Clonal hematopoiesis (CH) has been recently described as a novel driver for cancer and cardiovascular disease (CVD). Clonal hematopoiesis is a common, age-associated disorder marked by expansion of hematopoietic clones carrying recurrent somatic mutations. Current literature suggests that patients with CH have a higher risk of subsequent hematological malignant conditions and mortality attributable to excess CVD. This review discusses the association of cancer with CVD with CH as a potential unifying factor., Observations: The prevalence of CH varies based on the sequencing depth, diagnostic criteria, and patient age and ranges from less than 1% in those younger than 40 years to more than 15% to 20% in those 90 years and older. Clonal hematopoiesis is associated with a 0.5% to 1.0% absolute annual risk of hematological malignant condition and a 2-fold to 4-fold higher risk of coronary artery disease, stroke, and CVD deaths, independent of traditional cardiovascular risk factors. In fact, CH appears to have a relative risk similar to that of traditional cardiovascular risk factors for CVD. Experimental studies suggest that the link between CVD and CH is causal, with inflammation as 1 potential mechanism. There may be also a link between CH and CVD in survivors of cancer; however, data to support this association are currently limited., Conclusions and Relevance: Clonal hematopoiesis represents a premalignant state, with carriers having an increased risk of hematological malignant conditions. Although most carriers will not develop a malignant condition, CH confers an increased risk of CVD, possibly via inflammation. Clonal hematopoiesis may also contribute to CVD in survivors of cancer, although this hypothesis requires validation. Clinically, as advanced sequencing techniques become available, CH may pave the way for precision medicine in the field of cardio-oncology.

Importance: Immune checkpoint inhibitors (ICIs) are now a mainstay of cancer treatment. Although rare, fulminant and fatal toxic effects may complicate these otherwise transformative therapies; characterizing these events requires integration of global data., Objective: To determine the spectrum, timing, and clinical features of fatal ICI-associated toxic effects., Design, Setting, and Participants: We retrospectively queried a World Health Organization (WHO) pharmacovigilance database (Vigilyze) comprising more than 16 000 000 adverse drug reactions, and records from 7 academic centers. We performed a meta-analysis of published trials of anti-programmed death-1/ligand-1 (PD-1/PD-L1) and anti-cytotoxic T lymphocyte antigen-4 (CTLA-4) to evaluate their incidence using data from large academic medical centers, global WHO pharmacovigilance data, and all published ICI clinical trials of patients with cancer treated with ICIs internationally., Exposures: Anti-CTLA-4 (ipilimumab or tremelimumab), anti-PD-1 (nivolumab, pembrolizumab), or anti-PD-L1 (atezolizumab, avelumab, durvalumab)., Main Outcomes and Measures: Timing, spectrum, outcomes, and incidence of ICI-associated toxic effects., Results: Internationally, 613 fatal ICI toxic events were reported from 2009 through January 2018 in Vigilyze. The spectrum differed widely between regimens: in a total of 193 anti-CTLA-4 deaths, most were usually from colitis (135 [70%]), whereas anti-PD-1/PD-L1-related fatalities were often from pneumonitis (333 [35%]), hepatitis (115 [22%]), and neurotoxic effects (50 [15%]). Combination PD-1/CTLA-4 deaths were frequently from colitis (32 [37%]) and myocarditis (22 [25%]). Fatal toxic effects typically occurred early after therapy initiation for combination therapy, anti-PD-1, and ipilimumab monotherapy (median 14.5, 40, and 40 days, respectively). Myocarditis had the highest fatality rate (52 [39.7%] of 131 reported cases), whereas endocrine events and colitis had only 2% to 5% reported fatalities; 10% to 17% of other organ-system toxic effects reported had fatal outcomes. Retrospective review of 3545 patients treated with ICIs from 7 academic centers revealed 0.6% fatality rates; cardiac and neurologic events were especially prominent (43%). Median time from symptom onset to death was 32 days. A meta-analysis of 112 trials involving 19 217 patients showed toxicity-related fatality rates of 0.36% (anti-PD-1), 0.38% (anti-PD-L1), 1.08% (anti-CTLA-4), and 1.23% (PD-1/PD-L1 plus CTLA-4)., Conclusions and Relevance: In the largest evaluation of fatal ICI-associated toxic effects published to date to our knowledge, we observed early onset of death with varied causes and frequencies depending on therapeutic regimen. Clinicians across disciplines should be aware of these uncommon lethal complications.