Clinical Characteristics And Prognosis Of STEMI Patients With Bundle Branch Block

Objective:By retrospectively analyzing the clinical data,cardiac function indexes,coronary angiography results,and the incidence of major adverse cardiac events(MACE)in hospital of STEMI patients and STEMI patients complicated with BBB.To analyze the clinical features and prognosis of STEMI patients with and without BBB.Complete left bundle branch block(CLBBB)and Complete Right Bundle Branch Block(CRBBB)were further analyzed among STEMI patients with coronary artery disease,cardiac function status and other clinical characteristics and prognosis,to study the predictive value of STEMI patients combined with BBB on the occurrence of nosocomial MACE.Methods:1.A total of 62 patients with STEMI complicated with BBB diagnosed in the Department of Cardiology of the Second Affiliated Hospital of Kunming Medical University from January 2014 to October 2020 were enrolled as the study group,and 134 STEMI patients without BBB were randomly selected as the control group.All patients underwent emergency PCI successfully.According to the type of BBB,the study group was divided into two subgroups:17 patients with STEMI combined with LBBB(STEMI+LBBB),and 45 patients with STEMI combined with RBBB(STEMI+RBBB).All the selected BBB patients had complete bundle branch block,and BBB still existed in the last electrocardiogram before discharge.2.Collect the basic information of these patients,such as gender,age,smoking history,drinking history,history of hypertension,diabetes,all cases were in the hospital the next morning after eight hours on an empty stomach blood,blood related indicators,such as blood cell analysis,liver function,renal function,blood fat,myocardial injury markers selected hospitalization measured peak.All patients underwent emergency coronary angiography and Gensini score was calculated according to the results of coronary angiography,and the time of revascularization was recorded.Transthoracic ECG and 24-hour dynamic ECG examinations were performed within one week after admission.The length of hospital stay and the number of patients with in-hospital MACE were collected.3.Analyze and compare the clinical data,cardiac function indexes,heart rate variability,coronary angiography results,Gensini score,length of stay,incidence of MACE in hospital and other related indexes between the study group and the control group,the STEMI+LBBB group and the STEMI+RBBB group.Multivariate logistic regression was used to analyze the risk factors for in-hospital MACE events and the OR value of in-hospital MACE in STEMI patients with BBB.Results:1.Baseline data:There were no statistically significant differences in baseline data between the study group and the control group,and between the STEMI+LBBB group and the STEMI+RBBB group(P>0.05).2.Related indexes of blood test:Compared with the control group,the neutrophil/lymphocyte ratio(NLR),platelet/lymphocyte ratio(PLR),creatinine,creatine kinase isoenzyme(CK-MB),troponin T and myoglobin values in the study group were significantly higher than those in the control group,and the differences were statistically significant(P value was 0.001,0.011,0.014,0.004,0.001,0.001).There were no significant differences in NLR,PLR,creatinine,lipid indices and myocardial injury markers between STEMI+LBBB group and STEMI+RBBB group(P>0.05).3.Cardiac function indicators:Compared with the control group,the left ventricular end-diastolic diameter(LVDd),left atrial diameter(LAD)and N-terminus precursor brain natriuretic peptide(NT-proBNP)in the study group were significantly higher than those in the control group(P=0.001),and the level of left ventricular ejection fraction(LVEF)was decreased(P=0.001).The incidence of Killip cardiac function grade≥Ⅱ was higher(P=0.001),and the difference was statistically significant.Compared with STEMI+LBBB group and STEMI+RBBB group,NT-proBNP in STEMI+LBBB group was significantly increased(P=0.044)and LVEF level was decreased(P=0.006),the difference was statistically significant.Other differences were not statistically significant(P>0.05).4.Heart rate variability(HRV):The comparison between the study group and the control group showed that the standard deviation of NN interval(SDNN)of the study group,the standard deviation of the mean NN interval(SDANN),and the square root of the difference of the whole NN interval(RMSSD)were all decreased in the control group(P value was 0.018,0.036,0.032,respectively),and the differences were statistically significant.There was no significant difference in the percentage of the number of beats(PNN50)in the total number of beats(PNN50)between adjacent NN intervals with a difference of more than 50 ms(P>0.05).There was no significant difference in time domain analysis of heart rate variability between STEMI+LBBB group and STEMI+RBBB group(P>0.05).5.Comparison of coronary artery lesions:compared with the control group,the incidence of three coronary artery lesions was higher in the study group(P=0.001),the Gensini score was higher(P=0.001),and the proportion of anterior wall or extensive anterior wall myocardial infarction was higher(P=0.008).The main lesion vessel was the left anterior descending artery(P=0.001),the difference was statistically significant.STEMI+LBBB group and STEMI+RBBB group had a higher incidence of three coronary artery lesions(P=0.035),and there was no significant difference in infarct site,criminal vessel and Gensini score(P>0.05).6.Comparison of prognosis:The number of days in hospital and the incidence of in-hospital MACE in the study group were higher than those in the control group,with statistically significant differences(P=0.001).There was no significant difference in hospital stay and MACE event rate between STEMI+LBBB group and STEMI+RBBB group(P>0.05).7.Logistic regression analysis of risk factors for nosocomial MACE:Multivariate logistic regression analysis was performed,and the results indicated that age,CK-MB,and combined BBB were independent predictors of nosocomial MACE in STEMI patients.Conclusions:1.Patients with STEMI complicated with BBB,the infarct site is usually in the anterior wall or extensive anterior wall,the main culprit vessel is usually located in the left anterior descending branch,the number of three coronary artery lesions is more,the severity of lesions is more,the area of myocardial infarction is larger,the heart function is poor,and the prognosis is worse.2.Patients with STEMI complicated with LBBB had a higher proportion of three-vessel coronary lesions and worse heart function than patients with RBBB.3.Age,CK-MB and BBB were independent risk factors for MACE in STEMI patients.