title: In-hospital arrhythmia development and outcomes in pediatric patients with acute myocarditis.
abstract: Cardiac arrhythmias are a complication of myocarditis. There are no large studies of in-hospital arrhythmia development and outcomes in pediatric patients with acute myocarditis. This was a retrospective 2-center review of patients ≤21 years hospitalized with acute myocarditis from 1996 to 2012. Fulminant myocarditis was defined as the need for inotropic support within 24 hours of presentation. Acute arrhythmias occurred at presentation and subacute after admission. Eighty-five patients (59% men) presented at a median age of 10 years (1 day to 18 years). Arrhythmias occurred in 38 patients (45%): 16 acute, 12 subacute, and 9 acute and subacute (1 onset unknown). Arrhythmias were associated with low voltages on the electrocardiogram (14 of 34, 41% vs 6 of 47, 13%; odds ratio [OR] 4.78, 95% confidence interval [CI] 1.60 to 14.31) and worse outcome (mechanical support, orthotopic heart transplant, or death; OR 7.59, 95% CI 2.61 to 22.07) but were not statistically significantly associated with a fulminant course, ST changes, initial myocardial function, lactate, creatinine level, C-reactive protein and/or erythrocyte sedimentation rate, or troponin I level, after adjusting for multiple comparisons. Subacute arrhythmias were associated with preceding ST changes (10 of 15, 67% vs 15 of 59, 25%, OR 5.87, 95% CI 1.73 to 19.93). All patients surviving to discharge had arrhythmia resolution or control before discharge (10 on antiarrhythmic), with 1 exception (patient with complete heart block requiring a pacemaker). At 1-year follow-up, there were 3 recurrences of ventricular arrhythmias, but no arrhythmia-related mortality. In conclusion, arrhythmias are common in pediatric patients with myocarditis, occurring in nearly 1/2 of all hospitalized children and are associated with a worse outcome. Early identification of subacute arrhythmias using electrocardiographic changes may help management. A majority of patients do not require continued postdischarge arrhythmia treatment.
authors: Department of Pediatrics, Stanford University and Lucile Packard Children's Hospital, Palo Alto, California. Electronic address: cymiyake@texaschildrens.org.
authors: Christina Y
authors: CY
authors: Miyake
authors: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts.
authors: Sarah A
authors: SA
authors: Teele
authors: Department of Pediatrics, Stanford University and Lucile Packard Children's Hospital, Palo Alto, California.
authors: Liyuan
authors: L
authors: Chen
authors: Department of Pediatrics, Stanford University and Lucile Packard Children's Hospital, Palo Alto, California.
authors: Kara S
authors: KS
authors: Motonaga
authors: Department of Pediatrics, Stanford University and Lucile Packard Children's Hospital, Palo Alto, California.
authors: Anne M
authors: AM
authors: Dubin
authors: Department of Pediatrics, Stanford University and Lucile Packard Children's Hospital, Palo Alto, California.
authors: Sowmya
authors: S
authors: Balasubramanian
authors: Department of Health Research and Policy, Stanford University, Palo Alto, California.
authors: Raymond R
authors: RR
authors: Balise
authors: Department of Pediatrics, Stanford University and Lucile Packard Children's Hospital, Palo Alto, California.
authors: David N
authors: DN
authors: Rosenthal
authors: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts.
authors: Mark E
authors: ME
authors: Alexander
authors: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts.
authors: Edward P
authors: EP
authors: Walsh
authors: Department of Cardiology, Boston Children's Hospital, Boston, Massachusetts.
authors: Douglas Y
authors: DY
authors: Mah
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D001145:Arrhythmias, Cardiac / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D002648:Child; D002675:Child, Preschool; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007297:Inpatients; D008297:Male; D009205:Myocarditis / Q000150:complications* / Q000175:diagnosis / Q000503:physiopathology; D011379:Prognosis; D012189:Retrospective Studies; D013318:Stroke Volume; D015996:Survival Rate / Q000639:trends; D014481:United States / Q000453:epidemiology; D016277:Ventricular Function, Left / Q000502:physiology*