Retrospective Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Mar 6, 2019; 7(5): 548-561
Published online Mar 6, 2019. doi: 10.12998/wjcc.v7.i5.548
Clinical presentation and early predictors for poor outcomes in pediatric myocarditis: A retrospective study
Moises Rodriguez-Gonzalez, Maria Isabel Sanchez-Codez, Manuel Lubian-Gutierrez, Ana Castellano-Martinez
Moises Rodriguez-Gonzalez, Department of Pediatric Cardiology, Puerta del Mar University Hospital, Cadiz 11009, Spain
Maria Isabel Sanchez-Codez, Manuel Lubian-Gutierrez, Department of Pediatrics, Puerta del Mar University Hospital, Cadiz 11009, Spain
Ana Castellano-Martinez, Department of Pediatric Nephrology, Puerta del Mar University Hospital, Cadiz 11009, Spain
Author contributions: All authors helped to perform the research; Rodriguez-Gonzalez M contributed to the conception and design, performing procedures, manuscript writing, and data analysis; Sanchez-Codez MI contributed to the abstracted data, performing procedures, and manuscript writing; Castellano-Martinez A contributed to manuscript writing and data analysis; Lubian-Gutierrez M contributed to manuscript writing.
Institutional review board statement: This study was reviewed and approved by the Ethics Committee of the Puerta del Mar University Hospital.
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: All authors declare no conflicts-of-interest related to this article.
Data sharing statement: No additional data are available.
STROBE statement: The authors have included all the items included in STROBE statement for retrospective studies.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Moises Rodriguez-Gonzalez, MD, Doctor, Department of Pediatric Cardiology, Puerta del Mar University Hospital, Ana de Viya Avenue 34, Cadiz 11009, Spain.
Telephone: +34-95-6002700
Received: November 22, 2018
Peer-review started: November 23, 2018
First decision: December 15, 2018
Revised: December 29, 2018
Accepted: January 30, 2019
Article in press: January 30, 2019
Published online: March 6, 2019

Myocarditis is an important cause of morbidity and mortality in children, leading to long-term sequelae including chronic congestive heart failure, dilated cardiomyopathy, heart transplantation, and death. The initial diagnosis of myocarditis is usually based on clinical presentation, but this widely ranges from the severe sudden onset of a cardiogenic shock to asymptomatic patients. Early recognition is essential in order to monitor and start supportive treatment prior to the development of severe adverse events. Of note, many cases of fulminant myocarditis are usually misdiagnosed as otherwise minor conditions during the weeks before the unexpected deterioration.


To provide diagnostic clues to make an early recognition of pediatric myocarditis. To investigate early predictors for poor outcomes.


We conducted a retrospective cross-sectional single-center study from January 2008 to November 2017 at the Pediatric Department of our institution, including children < 18-years-old diagnosed with myocarditis. Poor outcome was defined as the occurrence of any of the following facts: death, heart transplant, persistent left ventricular systolic dysfunction or dilation at hospital discharge (early poor outcome), or after 1 year of follow-up (late poor outcome). We analyzed different clinical features and diagnostic test findings in order to provide diagnostic clues for myocarditis in children. Multivariable stepwise logistic regression analysis was performed using all variables that had been selected by univariate analysis to determine independent factors that predicted a poor early or late outcome in our study population.


A total of 42 patients [69% male; median age of 8 (1.5-12) years] met study inclusion criteria. Chest pain (40%) was the most common specific cardiac symptom. Respiratory tract symptoms (cough, apnea, rhinorrhea) (38%), shortness of breath (35%), gastrointestinal tract symptoms (vomiting, abdominal pain, diarrhea) (33%), and fever (31%) were the most common non-cardiac initial complaints. Tachycardia (57%) and tachypnea (52%) were the most common signs on the initial physical exam followed by nonspecific signs of respiratory tract infection (44%) and respiratory distress (35%). Specific abnormal signs of heart failure such as heart murmur (26%), systolic hypotension (24%), gallop rhythm (20%), or hepatomegaly (20%) were less prevalent. Up to 43% of patients presented an early poor outcome, and 16% presented a late poor outcome. In multivariate analysis, an initial left ventricular ejection fraction (LVEF) < 30% remained the only significant predictor for early [odds ratio (OR) (95%CI) = 21 (2-456), P = 0.027) and late [OR (95%CI) = 8 (0.56-135), P = 0.047) poor outcome in children with myocarditis. LVEF correlated well with age (r = 0.51, P = 0.005), days from the initiation of symptoms (r = -0.31, P = 0.045), and N-terminal pro-brain natriuretic peptide levels (r = 0.66, P < 0.001), but not with troponin T (r = -0.05, P = 0.730) or C-reactive protein levels (r = -0.13, P = 0.391). N-terminal pro-brain natriuretic peptide presented a high diagnostic accuracy for LVEF < 30% on echocardiography with an area under curve of 0.931 (95%CI: 0.858-0.995, P < 0.001). The best cut-off point was 2000 pg/mL with a sensitivity of 90%, specificity of 81%, positive predictive value of 60%, and negative predictive value of 96%.


The diagnosis of myocarditis in children is challenging due to the heterogeneous and unspecific clinical presentation. The presence of LVEF < 30% on echocardiography on admission was the major predictor for poor outcomes. Younger ages, a prolonged course of the disease, and N-terminal pro-brain natriuretic peptide levels could help to identify these high-risk patients.

Keywords: Myocarditis, Children, Echocardiography, N-terminal pro-brain natriuretic peptide, Myocardial ischemia, Cardiac magnetic resonance imaging, Heart transplantation, Dilated cardiomyopathy

Core tip: In this retrospective study involving 42 children with myocarditis, we delineated the heterogeneous and unspecific clinical presentation of this condition in order to provide clinical clues to improve its early recognition. We found that the presence of left ventricle ejection fraction < 30% on echocardiography on admission was the major predictor for poor early outcomes. Because echocardiography is not widely available at emergency departments, we found that younger ages (< 2-years-old), a prolonged course of the disease (> 7 d), and increased N-terminal pro-brain natriuretic peptide levels (> 5000 pg/mL) could help to identify these high-risk patients.