What Is the Evidence of the Diagnostic Criteria and Screening of Immune Checkpoint Inhibitor-Induced Myocarditis?

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Myocarditis is a rare, but serious, complication of immune checkpoint inhibitor therapy.

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The diagnosis of immune checkpoint inhibitor–induced myocarditis is sometimes challenging because of clinical, biological, and imaging features.

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Diagnostic criteria have been proposed to help clinicians, but have never been validated to date.

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Some guidelines now recommend early detection by repeated troponin and ECG testing, but its role has not yet been clearly demonstrated.

The Athletic ECG: A Line of Defense Against Misinterpretation

A 17-year-old competitive athlete was found to have a minor electrocardiogram abnormality on routine screening. Cardiac magnetic resonance revealed evidence of marked myocarditis, allowing a subsequent safe abstinence from exercise. The case highlights the importance of careful electrocardiogram interpretation, especially in athletes, where physiologic adaptive changes can pose a diagnostic challenge. (Level of Difficulty: Intermediate.).

Spontaneous Coronary Artery Dissection in a Transplanted Heart

We report the case of a 37-year-old man who presented with shortness of breath 1 year post heart transplantation. He was receiving tacrolimus, methylprednisolone, and mycophenolate. An angiogram showed spontaneous coronary artery dissection involving the left anterior descending artery. Percutaneous coronary intervention was performed successfully, with stent placement and return of flow. (Level of Difficulty: Advanced.).

Acute Myocarditis: A New Manifestation of Monkeypox Infection?

A 31-year-old male patient with confirmed monkeypox infection developed acute myocarditis days after the eruption of skin lesions. Cardiac magnetic resonance study confirmed myocardial inflammation. The patient was treated with supportive care and had full clinical recovery. This case highlights cardiac involvement as a potential complication associated with monkeypox. (Level of Difficulty: Intermediate.).

Missense Variant E1295K of Sodium Channel SCN5A Associated With Recurrent Ventricular Fibrillation and Myocardial Inflammation

SCN5A was considered an exclusively cardiac expressed ion channel but discovered to also act as a novel innate immune sensor. We report on a young SCN5A variant carrier with recurrent ventricular fibrillation and massive myocardial inflammation whose peculiar clinical course is highly suggestive of such a dual role of SCN5A. (Level of Difficulty: Advanced.)

PET-Driven, Voltage-Guided Atrial Endomyocardial Biopsy Clinches the Diagnosis of Cardiac Sarcoidosis

Endomyocardial biopsy (EMB) is used in diagnosing infiltrative and other suspected cardiomyopathies. We present a case in which positron emission tomography– and electroanatomic mapping-guided EMB of the atrial septum confirmed the diagnosis of cardiac sarcoidosis in a patient with negative findings on ventricular and lymph node biopsy. (Level of Difficulty: Advanced.)

Heart Transplantation for Early-Onset Anthracycline-Induced Cardiomyopathy Within 5 Months of Chemotherapy Completion

A 9-year-old boy developed progressive anthracycline-induced cardiomyopathy three months after completion of chemotherapy for osteosarcoma. Five months after completion of chemotherapy, at the age of 10 years, heart transplantation was performed. At 29 months since transplantation, the patient remains free of rejection and recurrence of osteosarcoma. (Level of Difficulty: Intermediate.).

Concomitant Transthyretin Amyloidosis and Severe Aortic Stenosis in Elderly Indian Population: A Pilot Study

BACKGROUND

Prevalence of both degenerative severe aortic stenosis (AS) and transthyretin cardiac amyloidosis (ATTR-CA) increases with age. Dual disease (AS+myocardial ATTR-CA) occurs in significant proportion of patients undergoing surgical aortic valve replacement (SAVR).

OBJECTIVES

This study aimed to determine the prevalence of ATTR-CA in severe AS in the Indian population, identify noninvasive predictors of its diagnosis, and understand its impact on prognosis.

METHODS

Symptomatic severe AS patients aged ≥65 years undergoing SAVR were enrolled. ATTR-CA diagnosis was based on preoperative 99m-technetium pyrophosphate (PYP) scan and intraoperatively obtained basal interventricular septum biopsy for myocardial ATTR-CA, and excised native aortic valve for isolated valvular ATTR-CA. Primary amyloidosis was excluded by serum/urine protein electrophoresis with serum immunofixation.

RESULTS

SAVR was performed in 46 AS patients (age 70 ± 5 years, 70% men). PYP scan was performed for 32 patients, with significant PYP uptake in 3 (n = 3 of 32, 9.4%), suggestive of myocardial ATTR-CA. On histopathological examination, none of the interventricular septum biopsy specimens had amyloid deposits, whereas 33 (71.7%) native aortic valves showed amyloid deposits, of which 19 (57.6%) had transthyretin deposition suggestive of isolated valvular amyloidosis. Noninvasive markers of dual disease included low myocardial contraction fraction (median [interquartile range], 28.8% [23.8% to 39.1%] vs 15.3% [9.3% to 16.1%]; P = 0.006), deceleration time (215 [144 to 236] ms vs 88 [60 to 106] ms; P = 0.009) and global longitudinal strain (-18.7% [-21.1% to -16.9%] vs -14.2% [-17.0% to -9.7%]; P = 0.030). At 1-year follow-up, 2 patients died (4.3%); 1 each in myocardial ATTR-CA negative and positive groups (3.4% vs 33.3%; P = 0.477).

CONCLUSIONS

Dual disease is not uncommon in India. Isolated valvular amyloidosis in severe AS is much more common.

Diagnosis and treatment of eosinophilic myocarditis

Eosinophilic myocarditis is a type of inflammatory cardiomyopathy characterized by eosinophilic infiltration into myocardial tissue. The accurate myocarditis incidence rate is difficult to determine because of the clinical limitations of an endomyocardial biopsy. The primary pathogenesis of eosinophilic myocarditis is the release of related substances by eosinophils, leading to cell membrane damage and cell destruction. However, evidence suggests that specific genes play a role in myocarditis development.As CMR imaging availability increases, the diagnosis rate of eosinophilic myocarditis will increase. The diagnosis of myocarditis mainly depends on an endocardial biopsy. Glucocorticoids can relieve patients' symptoms, but the early use of steroids may prevent intermediate disease stage development (i.e., thrombonecrosis and fibrosis with wall thrombosis). Anticoagulant therapy may also affect disease development. In addition to routine follow-up, a regular myocardial biopsy should be considered for discharged patients, if possible.

Hereditary Apolipoprotein A-I-Associated Cardiac Amyloidosis: Importance of Endomyocardial Biopsy When Suspicion Remains High

Cardiac amyloidosis has recently garnered substantial attention. Although the advent of noninvasive diagnostic algorithms revolutionized diagnosis, endomyocardial biopsy may still be considered in select cases to determine the amyloidosis subtype definitively. We report a case of a patients with a known mutation causing hereditary apolipoprotein A-I–associated cardiac amyloidosis. (Level of Difficulty: Advanced.)

Chloroquine Cardiotoxicity Leading to Cardiogenic Shock

A patient with a history of heart block and longstanding chloroquine use presented in cardiogenic shock refractory to medical therapy and mechanical circulatory support. Autopsy supported antimalarial-induced cardiomyopathy (AMIC). Progression of AMIC may be halted with early recognition and cessation of antimalarial therapy, highlighting importance of screening and timely diagnosis. (Level of Difficulty: Beginner.)

Biventricular Intravascular Microaxial Blood Pumps and Immunosuppression as a Bridge to Recovery in Giant Cell Myocarditis

We report a case of giant cell myocarditis in a 76-year-old patient managed with combined immunosuppression and biventricular intravascular microaxial blood pumps. This case highlights a feasible approach for managing such patients who are not candidates for transplantation or durable ventricular assist devices. (Level of Difficulty: Intermediate.)

Massive Myocardial Calcium Deposition: Hardened Heart

A 25-year-old African-American woman with end-stage renal disease presented with new-onset heart failure. Transthoracic echocardiography indicated a significantly hyperechoic myocardium, and computed tomography noted a circumferential hyperattenuated myocardium. Endomyocardial biopsy revealed focal interstitial and intramyocyte calcium deposition in the heart, confirming a rare diagnosis of massive myocardial calcium deposition. (Level of Difficulty: Beginner.).

Fulminant Eosinophilic Myocarditis: A Rare and Life-Threatening Presentation of Eosinophilic Granulomatosis With Polyangiitis

We describe a case of fulminant eosinophilic myocarditis as the first presentation of eosinophilic granulomatosis with polyangiitis, promptly managed with extracorporeal membrane oxygenation. This case highlights the multidisciplinary work involving all health care professionals in the acute management of these patients and discusses it from an educational point of view. (Level of Difficulty: Intermediate.)

Diagnosing cardiac amyloidosis in every-day practice: A practical guide for the cardiologist

Cardiac amyloidosis (CA) has emerged as a previously underestimated cause of heart failure and mortality. Underdiagnosis resulted mainly from unawareness of the true disease prevalence and the non-specific symptoms of the disease. CA results from extracellular deposition of misfolded protein fibrils, commonly derived from transthyretin (ATTR) or immunoglobulin light chains (AL). A significant proportion of older patients with heart failure and other extracardiac manifestations suffer from ATTR-CA, whereas AL-CA is still considered a rare disease. This article provides an overview of CA with a special focus on current and emerging diagnostic modalities. Furthermore, we provide a diagnostic algorithm for the evaluation of patients with suspected CA in every-day practice.

In Situ Immune Profiling of Heart Transplant Biopsies Improves Diagnostic Accuracy and Rejection Risk Stratification

Recognizing that guideline-directed histologic grading of endomyocardial biopsy tissue samples for rejection surveillance has limited diagnostic accuracy, quantitative, in situ characterization was performed of several important immune cell types in a retrospective cohort of clinical endomyocardial tissue samples. Differences between cases were identified and were grouped by histologic grade versus clinical rejection trajectory, with significantly increased programmed death ligand 1+, forkhead box P3+, and cluster of differentiation 68+ cells suppressed in clinically evident rejections, especially cases with marked clinical-histologic discordance. Programmed death ligand 1+, forkhead box P3+, and cluster of differentiation 68+ cell proportions are also significantly higher in "never-rejection" when compared with "future-rejection." These findings suggest that in situ immune modulators regulate the severity of cardiac allograft rejection.

A Case of Heart Failure in a Patient With Systemic Lupus Erythematosus

Patients with systemic lupus erythematosus (SLE) can present with multiple cardiovascular pathologies, including pulmonary hypertension, valvular disease, pericarditis, myocarditis, and premature atherosclerosis. SLE medications can also cause cardiovascular side effects. We present a patient who developed a severe cardiomyopathy secondary to the hydroxychloroquine prescribed to treat her SLE. (Level of Difficulty: Beginner.).

Progressive Thinning of the Basal Interventricular Septum by Giant Cell Myocarditis

We describe a patient with ventricular tachycardia and complete atrioventricular block. Remarkable thinning of the basal interventricular septum preceded left ventricular dysfunction. Endomyocardial biopsy demonstrated giant cell myocarditis. The patient received combined immunosuppressive therapy and a cardioverter-defibrillator. Eligibility screening for heart transplantation was initiated. (Level of Difficulty: Advanced.)

Multimodality Imaging Reveals Divergent Responses of Left and Right Heart to Treatment in Cardiac Amyloidosis

Cardiac amyloidosis is associated with very high morbidity and mortality. Only if treated early, cardiac amyloidosis responds well to therapy, and early recognition with a full differential diagnostic workup including multimodality imaging is therefore critical at first presentation. Closely meshed clinical monitoring and imaging are indispensable to ensure optimal individualized treatment. (Level of Difficulty: Beginner.).

Biopsy-Proven Lymphocytic Myocarditis With Heart Failure in a Middle-Aged Female Patient With Mixed Connective Tissue Disease

A 56-year-old woman with mixed connective tissue disease, who was on maintenance immunosuppression, developed asymptomatic left ventricular dysfunction, ventricular arrhythmia, and high troponin I. Heart catheterization showed normal coronaries and biopsy-proven, virus-negative lymphocytic myocarditis. A biopsy-guided immunosuppression upgrade effectively treated autoimmune myocarditis, which resulted in ventricular function recovery, resolution of arrhythmia, and of troponin release. (Level of Difficulty: Advanced.).

Transcriptomic Analysis Identifies the Effect of Beta-Blocking Agents on a Molecular Pathway of Contraction in the Heart and Predicts Response to Therapy

Over the last decades, beta-blockers have been a key component of heart failure therapy. However, currently there is no method to identify patients who will benefit from beta-blocking therapy versus those who will be unresponsive or worsen. Furthermore, there is an unmet need to better understand molecular mechanisms through which heart failure therapies, such as beta-blockers, improve cardiac function, in order to design novel targeted therapies. Solving these issues is an important step towards personalized medicine. Here, we present a comprehensive transcriptomic analysis of molecular pathways that are affected by beta-blocking agents and a transcriptomic biomarker to predict therapy response.