Clinical Findings Of Cardiac Injury In Avian Influenza A (H7N9) Hospitalized Patients

Objective:To understand the incidence and characteristics of cardiac injury in hospitalized patients with A(H7N9)infection.To investigate the correlation between characteristics of cardiac injury and outcomes.Methods:We included 338 patients with laboratory-confirmed avian influenza A(H7N9)virus infection during January 22,2015-June 16,2017.Medical records were from H7N9-China database.During collating the information of 338 hospitalized patients,we got the incidence of cardiac injury.Due to the missing of clinical outcome in 14 patients and virological data in 3 patients,321 patients5 data including examinations of cardiac biomarkers,ECG and ECHO were used for further analysis.After basing on reference and combining with clinical features,cardiac injury was defined as follows:1.Any elevation of cardiac biomarkers(TNI,CK,CK-MB);if there is only the result of the biomarkers,TNI must be elevated and dynamically changed;2.Inpatients without coexisting cardiac diseases have new abnormalities in ECG and/or ECHO,sinus tachycardia(heart rate?130 bpm),sinus bradycardia(heart rate<50 bpm);new abnormalities or a worsening of the underlying state in ECG and/or ECHO after viral infection in patients with coexisting heart disease;3.One or more of the following complications after viral infection:arrhythmia,myocarditis,pericarditis,acute myocardial infarction,heart failure,cardiogenic shock,sudden cardiac arrest;new cardiac injury or a worsening of the underlying state after viral infection in patients with coexisting heart disease.Myocardial injury was defined as elevated troponin ? on account of elevation of troponin ? level is more specific and sensitive for myocardial damage.Cardiac injury was defined for confirming cardiac injured cases.Clinical features of cardiac injury and correlation between cardiac injury and outcomes were analyzed.Results:In 338 cases,249(73.7%)with cardiac injury in whom 90(26.6%of 338)with myocardial injury.By further analyzing 321 H7N9 hospitalized patients(233 injured,88 uninjured),patients with cardiac injury had older mean age,cardiovascular comorbidity and mortality than uninjured patients(P<0.05).More injured cases suffered from dyspnea and lower extremity edema(P<0.001).Patients with cardiac injury had higher APACHE? scores,lower oxygenation index and decreased rate of viral shedding(P<0.001).In cardiac injured patients,cardiac biomarkers were more elevated in death and non-shedding group than in survival group and virus shedding group,more ECG abnormalities and cardiac complications were shown in injured patients(P<0.05).Cardiac injury was an independent risk factor associated with death(adjusted OR,5.03;95%Cl,1.80-14.02).The median duration of A(H7N9)RNA shedding was 20 days in cardiac injured group and 16 days in uninjured group.Duration of A(H7N9)RNA shedding was significantly longer in injured group(log-rank P,<0.001).APACHE ? score?21(adjusted OR,3.24;95%Cl,1.26-8.34),level of white blood cell count(adjusted OR,1.15;95%Cl,1.03-1.28),viral non-shedding(adjusted OR,5.14;95%Cl,2.07-12.81)and positive fluid balance(adjusted OR,2.42;95%Cl,1.30-4.52)were the independent risk factors of cardiac injury in 321 H7N9 hospitalized patients.Risk factors for myocardial injury were APACHE ? score?21(adjusted OR,2.21;95%Cl,1.01-4.84)and viral non-shedding(adjusted OR,3.86;95%Cl,1.82-8.17).By the analysis of the treatment,death group showed significantly higher proportions of therapy with vasopressor and intensive mechanical ventilation in both cardiac injured and uninjured cases(P<0.001).In patients with cardiac injury,higher proportions of positive fluid balance and immunomodulatory treatment with gamma globulin were shown in death group than those in survival group(P<0.05).Lower proportion of anticoagulation treatment was shown in injured death group(P<0.05).Conclusion:Cardiac injury was common in hospitalized patients with A(H7N9)avian influenza virus infection.Compared with cardiac injury,the proportion of patients with myocardial injury was not high.Cardiac injury was an independent risk factor associated with death and the duration of viral shedding.Patients with APACHE ? score?21 and viral non-shedding should be paid more attention to cardiac and myocardial injury.For the hospitalized patients with A(H7N9)avian influenza virus infection,cardiac examinations would be necessary.