Last reviewed: 1 Sep 2023
Last updated: 12 Jul 2023



History and exam

Key diagnostic factors

  • viral syndrome (prior)
  • autoimmune disease
  • infectious disease
  • drugs and toxins
More key diagnostic factors

Other diagnostic factors

  • age <50 years
  • chest pain
  • dyspnea
  • orthopnea
  • fatigue
  • palpitations
  • rales
  • elevated neck veins
  • S3 gallop
  • sinus tachycardia
  • atrial and ventricular arrhythmias
  • tachypnea
  • hepatomegaly
  • syncope
  • fever
  • gastrointestinal issues
  • rhinorrhea
  • cough
  • S3 and S4 summation gallop
  • pericardial friction rub
  • peripheral hypoperfusion
  • hypotension
  • altered sensorium
  • lymphadenopathy
  • respiratory distress
Other diagnostic factors

Risk factors

  • infection (non-HIV)
  • HIV infection
  • autoimmune/immune-mediated diseases
  • peripartum and postpartum periods
  • drugs and toxins
More risk factors

Diagnostic investigations

1st investigations to order

  • 12-lead ECG
  • CXR
  • serum CK
  • serum CK-MB
  • serum troponin (I or T)
  • serum B-type natriuretic peptide
  • two-dimensional echocardiogram
More 1st investigations to order

Investigations to consider

  • endomyocardial biopsy (EMB)
  • coronary angiography
  • 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET-CT)
  • cardiac MRI
  • viral polymerase chain reaction (PCR)
More investigations to consider

Emerging tests

  • MRI-guided EMB

Treatment algorithm


hemodynamically stable: no evidence of LV systolic dysfunction

hemodynamically stable: evidence of LV systolic dysfunction

hemodynamically unstable: adults

hemodynamically unstable: children


end-stage heart failure or refractory life-threatening arrhythmias



Shriprasad R. Deshpande, MBBS, MS

Medical Director

Heart Transplant and Advanced Cardiac Therapies Program

Children's National Hospital

Associate Professor of Pediatrics

The George Washington University




SRD declares that he has no competing interests.

Bibhuti Das, ​MBBS, MD, FAAP, FACC

Pediatric Cardiology

Chief, McLane Children’s Hospital, BSW Medical Center

Baylor Scott and White Medical Center

Professor of Pediatrics

Baylor College of Medicine-Temple

Director of ACHD and CPET




BD declares that he has no competing interests.


Dr Shriprasad R. Deshpande and Dr Bibhuti Das would like to gratefully acknowledge Dr Katherine C. Wu, Dr James E. Harvey, and Dr Arman T. Askari, previous contributors to this topic. KCW, JEH, and ATA declare that they have no competing interests.

Peer reviewers

David A. Leaf, MD, MPH

Professor of Medicine

School of Medicine

VA Greater Los Angeles Healthcare System


Los Angeles



DAL declares that he has no competing interests.

John Charpie, MD, PhD

Associate Professor of Pediatrics

Medical Director

Pediatric Cardiothoracic Intensive Care Unit

University of Michigan Congenital Heart Center

Ann Arbor



JC declares that he has no competing interests.

Lokesh Tejwani, MD, FACC

Assistant Professor of Clinical Medicine

University of Missouri Hospitals and Clinics

Harry S. Truman VA Hospital




LT declares that he has no competing interests.

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