Analysis Of ECG And Clinical Characteristics Of Arrhythmia In Patients With Acute Viral Myocarditis

Objective To investigate the electrocardiogram(ECG)characteristics and clinical characteristics of arrhythmia in patients with acute viral myocarditis(VMC),and to find abnormal ECG manifestations and related clinical risk factors.Early identification of patients with acute fulminant myocarditis(AFM)and to provide a reliable basis for clinical diagnosis and treatment.Methods A total of 126 VMC patients admitted to the General Hospital of Ningxia Medical University from January 2012 to January 2022 were retrospectively collected.According to the collected medical records,the patients were divided into AFM group and non-AFM group according to the occurrence of Adams-Strauss syndrome and/or malignant arrhythmia.Data collected included gender,age,laboratory tests,electrocardiogram,echocardiography,cardiac magnetic resonance imaging and other tests and examinations of the two groups of patients.Univariate and multivariate logistic regression analysis were used to establish a multiple risk factor model to identify the relevant independent predictors of AFM patients.Results1.A total of 126 VMC patients were enrolled in this study,including 77 males(61.1%)and 49 females(38.9%),with a male to female ratio of 8:5.Among all the patients,the oldest was 66 years old,the youngest was 15 years old,and the average age was 32.04±13.17 years old.The average age of male was 30.58±13.28 years old,and the average age of female was34.33±12.79 years old.There were 54 patients(42.9%)in the AFM group,including 27 males(50.0%).There were 72 patients(57.1%)in the non-AFM group,including 50 males(69.4%).2.A total of 118 patients(93.6%)had prodromal history,of which 104 patients(82.5%)had upper respiratory symptoms and 14 patients(11.1%)had gastrointestinal symptoms.3.The most common symptoms were chest pain(61 cases,48.4%),followed by shortness of breath(79 cases,62.7%),palpitation(42 cases,33.3%),and fever(49 cases,38.9%).The AFM group had a significantly higher proportion of patients with shortness of breath and palpitations than the non-AFM group(P < 0.05),while there was no significant difference in the proportion of chest pain,fever,nausea,emesis,dizziness,and fatigue(P >0.05).4.Laboratory parameters such as cardiac markers,myocardial enzymes and coagulation indexes in VMC patients were significantly higher than normal parameters.The abnormal levels of alanine aminotransferase(ALT),aspartate aminotransferase(AST),creatine kinase(CK),creatine kinase isoenzyme(CK-MB),lactate dehydrogenase(LDH),brain natriuretic peptide(BNP),troponin I(c TnI),prothrombin time(PT),C-reactive protein(CRP)and albumin in AFM group were higher than those in non-AFM group The level of prothrombin activity(PTA)in AFM group was lower than that in non-AFM group(P < 0.05).5.Among the abnormal ECG changes,the proportion of patients with prolonged PR interval,widened QRS wave and prolonged QTc interval in the AFM group was significantly higher than that in the non-AFM group(P < 0.05),while the proportion of ST segment elevation and T wave inversion had no significant difference between the two groups(P >0.05).6.Among the various types of arrhythmia in VMC patients,7 cases(5.5%)had sinus tachycardia,8 cases(6.3%)had atrial fibrillation(AF),and 8 cases(6.3%)had atrial fibrillation.premature ventricular contractions(PVC)and ventricular arrhythmia(VA)were found in 25(19.8%)and 30(23.8%)patients respectively.There were 8 cases(6.3%)of ventricular fibrillation(VF),7 cases(5.6%)of complete left bundle block(CLBBB),and 8cases(6.3%)of complete left bundle block(CLBBB).There were 25 patients(19.8%)with complete right bundle block(CRBBB),8 patients(6.3%)with second-degree atrioventricular block,and 26 patients(26.9%)with third-degree atrioventricular block.The incidences of VA,VF,CRBBB and third degree atrioventricular block in the AFM group were significantly higher than those in the non-AFM group(P < 0.05),while there were no significant differences in the incidences of AF,PVC,CLBBB,sinus tachycardia and second degree atrioventricular block(P > 0.05).7.According to echocardiography,67 cases(53.2%)had abnormal ventricular wall motion,66 cases(52.4%)had pericardial effusion,and the left ventricular ejectionfraction(LVEF)was 54.25±13.49%.Compared with the non-AFM group,the AFM group had a lower LVEF(P < 0.05),a higher incidence of pericardial effusion(P < 0.05),and more abnormal ventricular wall motion(P < 0.05).8.Among the 16 patients who underwent Cardiac magnetic resonance imaging(CMR),7 cases(43.6%)showed diffuse or localized enhancement on T2 WI,8 cases(50.0%)showed early enhancement,and 12 cases(75.0%)showed late delayed enhancement.9.There were 11 patients(20.4%)in the AFM group treated with extracorporeal membrane oxygennation(ECMO),and 8 of them(72.7%)were discharged after treatment.Intra-aortic balloon pump(IABP)was used in 5 cases(9.3%),and 5 cases(100%)treated with IABP were discharged from the hospital or died.A total of 18 patients(33.3%)were implanted with temporary pacemaker,and 15 patients(83.3%)had good clinical benefits.10.Multivariate logistic regression analysis showed that palpitations(OR=5.338,95%CI: 1.419-20.079,P=0.013),shortness of breath(OR=5.307,95%CI: 1.355-20.793,P=0.017),widened QRS complex(OR=0.947,95%CI: 1.419-20.079,P=0.013),95%CI:0.912-0.983,P=0.004),QTc interval prolongation(OR=0.983,95%CI: 0.968-0.997,P=0.019),third degree atrioventricular block(OR=5.747,95%CI: 1.171-1.200,P=0.019),P=0.031)were related factors for predicting arrhythmia in acute severe myocarditis.Conclusion Upper respiratory tract and gastrointestinal infection are the most common prodromal history of VMC patients,and the main clinical manifestations are chest pain,shortness of breath,palpitation and fever.Myocardial enzymes,cardiac markers and coagulation function have different abnormal manifestations in different stages of the disease,which can help to judge the progress of the disease.PR interval prolongation,QRS wave widening and QTc interval prolongation were more common in AFM patients.Among the types of arrhythmias,AFM patients had a higher proportion of ventricular tachycardia,ventricular fibrillation,complete right bundle branch block,and third degree atrioventricular block.Palpitation,shortness of breath,widened QRS wave,prolonged QTc interval and third degree atrioventricular block are independent risk factors for AFM.