Myocardial dysfunction in pediatric septic shock

Abstract

Objective: To evaluate the prevalence and significance of myocardial dysfunction in children with septic shock.

Study design: Thirty patients with septic shock were evaluated by transthoracic echocardiography within 24 hours of admission to a pediatric critical care unit. Transthoracic echocardiography evaluation included left ventricular (LV) size and function, mitral valve inflow velocities in early and late diastole, mitral valve annular velocities in systole and early and late diastole, and LV myocardial performance index. LV systolic dysfunction was defined as an ejection fraction or shortening fraction z-score <-2, and LV diastolic dysfunction was defined as a mitral valve inflow velocity/annular velocity in early diastole ratio z-score >2. Secondary outcomes included troponin I concentration, acute kidney injury, and 28-day mechanical ventilation-free duration.

Results: Mortality for the 30 patients (mean age, 9.5 ± 7 years) was 7%. The prevalence of LV systolic and/or diastolic dysfunction was 53% (16 of 30). Eleven patients (37%) had systolic dysfunction, 10 (33%) had diastolic dysfunction, and 5 (17%) had both. Systolic and/or diastolic dysfunction was significantly associated with troponin I level (P = .007) and acute kidney injury (P = .02), but not with ventilation-free duration (P = .12). Kaplan-Meier analyses for pediatric critical care unit and hospital length of stay identified no differences between patients with and those without myocardial dysfunction.

Conclusion: Myocardial dysfunction occurs frequently in children with septic shock but might not affect hospital length of stay.

Keywords: A; E; EF; Ejection fraction; IVA; LV; Left ventricular; MPI; Mitral valve annular acceleration during isovolumic contraction; Mitral valve annular velocity during systole; Mitral valve annular velocity in early diastole; Mitral valve annular velocity in late diastole; Mitral valve inflow velocity in early diastole; Mitral valve inflow velocity in late diastole; Myocardial performance index; PCCU; PELOD; Pediatric Logistic Organ Dysfunction; Pediatric Risk, Injury, Failure, Loss, and End-Stage Kidney Disease; Pediatric critical care unit; RV; Right ventricular; TTE; Transthoracic echocardiography; pRIFLE; á; é; ś.