# Epidemiology and prognosis of pediatric acute myocarditis: a 5-year retrospective study in Shiraz, South of Iran running title: pediatric acute myocarditis in Iran

## TL;DR

This study examines the causes and outcomes of pediatric acute myocarditis in Iran and identifies key factors that may help predict which patients are at higher risk.

## Contribution

The study identifies hepatomegaly and reduced ejection fraction as potential prognostic indicators for high-risk pediatric myocarditis patients.

## Key findings

- Patients requiring intubation had significantly higher inotrope scores.
- Hepatomegaly and decreased left ventricular ejection fraction were associated with worse outcomes.
- Elevated inotrope scores correlate with the need for mechanical ventilation and cardioversion.

## Abstract

Early diagnosis, appropriate management, and vigilant follow-up can lead to the recovery and improved quality of life in many pediatric myocarditis cases. Due to the rarity of this condition, a comprehensive understanding of its epidemiology and outcomes is essential.

This study aims to provide a thorough epidemiological analysis of pediatric clinically suspected myocarditis and introduce a potential prognostic tool for identifying high-risk patients.

A retrospective cross-sectional study was conducted on patients admitted to Namazi Hospital with clinically suspected myocarditis. Demographic, clinical, laboratory, imaging data, and vasoactive inotrope scores were collected from the beginning of hospitalization and throughout the patients’ stay. Critical hospital events such as cardioversion, intensive care unit (ICU) care, and mechanical ventilation were documented.

A total of 117 children, including 103 (88%) males, were included in the final evaluation. Patients who required intubation had significantly higher inotrope scores (p-value < 0.0001). Moreover, statistically significant differences were observed in the outcomes of patients presenting with hepatomegaly and decreased left ventricular ejection fraction (P = 0.022).

The identification of hepatomegaly and reduced ejection fraction as potential prognostic indicators represents a significant contribution to the field. These findings may assist clinicians in recognizing high-risk patients who require more aggressive treatment and closer monitoring. Patients with elevated inotrope scores are more likely to necessitate mechanical ventilation and cardioversion.