[Related factors for the development of fulminant myocarditis in adults]

Objective: To determine the early recognizable factors related to patients with fulminant myocarditis. Methods: Medical records from 60 adult patients who were diagnosed with acute viral myocarditis from January 2003 to September 2016 in our hospital were retrospectively reviewed, and divided into the fulminant group (n=9) and the non-fulminant group (n=51). Clinical presentations, biochemical markers, electrocardiography and echocardiography features on admission were analyzed. Results: Prevalence of syncope (33.3%(3/9) vs. 2.0% (1/51), P=0.009) and fatigue (77.8% (7/9) vs. 21.6% (11/51) , P=0.002) was significantly higher, while the duration from flu-like syndromes to chest discomfort was shorter ((2.0±1.8) days vs. (4.5±3.5) days, P=0.041) in the fulminant group than that in the non-fulminant group. Systolic blood pressare (SBP) ((94±14) mmHg(1 mmHg=0.133 kPa) vs. (117±12)mmHg, P=0.001) and left ventricular ejection fraction((49±12)% vs. (60±13)%, P=0.016) were significantly lower, while heart rate ((99±20)bpm vs. (84±19)bpm, P=0.040) and NT-proBNP concentration ((7 962 (1 470, 23 849) ng/L vs. 1 771 (45, 2 380) ng/L, P=0.000) were significantly higher in the fulminant group than those in the non-fulminant group. PR interval was longer (199 (140, 416) ms vs. 156 (112, 204) ms, P=0.021), QRS complex was wider ((127±14)ms vs. (95±13)ms, t=-6.647, P<0.001) in the fulminant group than those in the non-fulminant group. Prolonged QRS duration≥120 ms was more often in fulminant group (77.8%(7/9) vs. 5.9%(3/51), P=0.000). Multivariate analysis revealed that PR interval (adjusted odd ratio 1.044, 95%CI 1.005-1.084, P=0.025) and QRS complex width (adjusted odd ratio 1.252, 95%CI 1.045-1.501, P=0.015) were the independent risk factors significantly associated with fulminant myocarditis. Conclusions: The risk of a fulminant course of acute myocarditis is higher in patients with elevated NT-proBNP, reduced left ventricular ejection fraction, and conduction disturbances at admission. Prolonged PR interval and widened QRS complex on admission are independent risk factors for developing fulminant myocarditis in adult patients with acute viral myocarditis.