Effect Ofnew-onset Atrial Fibrillation On Short-term Prognosis In Patients With Acute Myocardial Infarction Underwent Emagency PCI

BackgroundAtrial fibrillation(AF)is common in patients with acute myocardial infarction(AMI),with the incidence ranging from 5%to 23%.AF in the setting of AMI can cause a series of hemodynamic disorders and subsequent increasing of clinical adverse events:loss of pump function in the atrium may cause an obvious decline in cardiac output and rapid and irregular ventricular rate can aggravate hemodynamic disorders and coronary circulatory disorders,along with activated sympathetic nervous system.All can lead to an obvious increase in the incidence of adverse events,such as congestive heart failure,cardiogenic shock,malignant ventricular fibrillation and sudden death during the acute phase of AMI.With the development of treatment strategies for AMI,especially the improvement of percutaneous coronary intervention(PCI)and wide application of medicines,such as ACE-inhibitors and P-blockers,incidence of AF in patients with AMI has been decreased recently,nonetheless higher than in the general population.Meanwhile recent studies still have revealed that the adverse impact of new-onset AF on short-and long-term prognosis in patients who underwent primary PCI for AMI.However,there are only a few contemporary studies investigating the effect of new-onset AF on prognosis in patients treated invasively for AMI.This paper was devoted to further exploring association between new-onset AF and major adverse events during hospitalization in patients with AMI after emergency PCI,in order to help clinicians to better evaluate high-risk characteristics of the patients,and to determine appropriate prevention and treatment strategies with the purpose of improving their short-term prognosis.Objectives(1)To evaluate the impact of new-onset atrial fibrillation on short-term prognosis in patients underwent emergency PCI for AMI.(2)To investigate the predictors of new-onset atrial fibrillation treated with emergency PCI.Subjects and methodsIn this retrospective cohort study,we recruited 300 consecutive hospitalized patients with AMI treated with primary PCI from January 1,2011 to December 31,2016 at the Department of Cardiology in our hospital.Among the 300 patients,there were 32 patients with new-onset atrial fibrillation named AF group,and 268 patients without new-onset atrial fibrillation named non-AF group.In the two groups,medical records during hospitalization were analyzed,including important clinical features,main medication,and major adverse events.Multivariate logistic regression model was used to investigate the effect of new-onset atrial fibrillation on short-term prognosis of patients with AMI after emergency PCI,accompanied by identifying the predictors of new-onset atrial fibrillation.Results1.Incidence of new-onset AFAmong the 300 patients,new-onset AF was diagnosed in 32(10.67%)patients.2.Comparison of important clinical features(1)Compared with patients without new-onset AF,patients with new-onset AF had longer in-hospital stay(11.38 ± 11.00 vs.8.74 ± 2.33,P=0.001).Patients who developed AF during hospitalization were older(67.94± 12.27 vs.60.04± 11.57,P =0.001)and more belonged to advanced age(≥ 70 years),and meanwhile more likely had heart failure on admission(21.9%vs.4.9%,P<0.001).Compared with patients in non-AF group,patients in AF group had a lower rates of systolic blood pressure on admission(115.53±18.87 vs.127.38±21.95,P=0.002),lower eGFR(P = 0.035),and higher neutrophil counts(13,54±13.30 vs.9.14±3.00,P<0.001)and higher proportion of neutrophils(83.83±5.92 vs.78.04±9.08,P<0.001).There were no major difference between the two groups in terms of heart rate on admission,WBC count,peak troponin I level,serum creatinine and uric acid,along with history of hypertension,diabetes and old myocardial infarction.(2)Between the two groups,there was no significant difference in terms of infarct-related arteries,preprocedural TIMI grades,collateral circulation,the number of lesion vessels,and postprocedural TIMI grades.Patients in AF group had higher rates of no-reflow than the counterparts(6.3%vs.3.0%)in the non-AF group.However,the difference had no statistical significance(P = 0.290).(3)There was no significant difference in terms of low wall motion index between the two groups.On the other hand,compared with patients without new-onset AF,patients with new-onset AF had larger left atrial diameter(34.38±4.23 vs.32.42±4.63,P = 0.024),and lower left ventricular ejection fraction(49.20±8.16 vs.53.53±8.71,P = 0.008).3.Comparison of major medication during hospitalizationCompared with patients in non-AF group,patients in AF group were less charged on β-blockers(59.4%vs.37.3%,P = 0.016).However,no significant difference was found in terms of antithrombotic regimens,ACE-inhibitors,ARB,nitrates,and statins.4.Predictors of new-onset atrial fibrillationBinary logistic regression model showed advanced age(odds ratio[OR]5.159,95%confidence interval[CI]2.252-11.817;P<0.001),increased proportion of neutrophils(OR 6.995,95%CI 1.548-31.609;P = 0.011)and larger left atrial diameter(OR 1.155,95%CI 1.042-1.281;P = 0.006)were independent predictors of new-onset atrial fibrillation.5.Effect of new-onset AF on major adverse events during hospitalizationMultivariate logistic regression analysis showed that new-onset AF was independent risk factors for all the ad-verse events during hospitalization.After adjustment for confounding factors,new-onset atrial fibrillation was shown to be strong independent predictors of bleeding(B = 1.374,95%CI 0.619-2.129;P<0.001).And new-onset atrial fibrillation remained associated with cardiogenic shock(OR 4.919,95%CI 1.056-22.911;P = 0.042),malignant ventricular arrhythmia(OR 3.298,95%CI 1.276-8.527;P = 0.014)and event-free survival(OR 0.320,95%CI 0.130-0.787;P= 0.013).Conclusion1.New-onset atrial fibrillation was independent predictors of bleeding,cardiogenic shock,malignant ventricular arrhythmia and event-free survival in patients with AMI treated with emergency PCI during hospitalization.2.Advanced age,higher proportion of neutrophils and enlarged left atrial diameter were independent predictors of new-onset atrial fibrillation in patients underwent emergency PCI for AMI.