The Influence And Prognosis Analysis Of Fragmented QRS Complex For Acute Myocardial Infarction By The Therapy Of Percutaneous Coronary Interention

Objective: Myocardial infarction (MI) patients’ infarction myocardial will formpart of the scar tissue, and the myocardial scar will directly influence the ventriculardepolarization, and then lead to conduction abnormalities, so fragmented QRS (fQRS)developed on the electrocardiogram (ECG), which on ECG was defined by the presenceof single or multiple notches in the R or S wave or various RSR’patterns,without atypical bundle branch block. For the patients of AMI， which accepted PCIintervention, fQRS may change with the improvement of myocardial ischemia, andthere is a certain value for the long-term prognosis of patients, such as the incidenceventricular arrhythmias and mortality. Therefore, we further study the change of fQRSon ECG for AMI which accept emergency PCI, or optional refuse to PCI, and whetherthe fQRS affects the long-term prognosis of patients with AMI.Methods:137cases of patients with diagnosis of AMI (mean age,60.5±12.5years,109males,28females),including125cases of ST-segment elevation myocardialinfarction (STEMI), and12cases of non ST-segment elevation myocardial infarction(NSTEMI),who accept PCI therapy (31cases accept emergency PCI,61cases acceptoptional PCI, and45cases refuse to PCI).When they are hospitalized, preoperative andpostoperative PCI, after1week of PCI, after2weeks of PCI and after6months of PCI,accept conventional ECG examination respectively, so that we can observe theevolution of the fQRS. At the same time, we evaluated the patients’ level cardiacfunction and left ventricular ejection fraction (LVEF) by heart echocardiography. Thosepatients with post-operative PCI were followed up for6months. Meanwhile, according to the body surface ECG with the fQRS or not，the patients were separated into twogroups, and we compared the incidence of ventricular arrhythmia between the twogroups.Results: In137patients, accepted preoperative PCI examination of ECG, wedeveloped14cases (45.16%) whose ECG appeared the fQRS on the infarctioncorresponding leads in emergency PCI group, in another two groups the numberrespectively is35cases(57.38%)、21cases（46.67%）.1. In the emergency PCI group, the fQRS incidence on ECG more lower thanrefused to PCI group after two weeks of PCI (P=0.002); In the optional PCI group, thefQRS incidence on ECG more lower than refuse to PCI group after two weeks of PCI(P=0.020); In the emergency PCI group, the fQRS incidence on ECG more lower thanoptional PCI group after six months of PCI (P=0.008). It is suggested that the openingcoronary arteries early can save the myocardial ischemic and reduce the forming ofmyocardial scar, and reduce the incidence of fQRS on ECG.2. The incidence of ventricular arrhythmias was obviously higher in the group thatappeared fQRS on ECG than the other group without fQRS on ECG, which have astatistics difference (P=0.028). It is suggested that the forming of fQRS imply themyocardial scar tissue, and in this condition the incidence of ventricular arrhythmiaobviously higher.3. In this study，including2cases died, a case dead because of cardiac ruptureduring be in hospital who accepted emergency PCI; the other case dead because offrequent ventricular arrhythmias, including Ventricular tachycardia(VT) and Ventricularfibrillation(Vf), who refused to PCI. But it was not that whether there are relationshipbetween the fQRS and the mortality after MI.Conclusion:1. To the patients with AMI, the fQRS has some of the diagnostic value, it issuggested that the fQRS may have a certain prediction value for the happening to MI.2. Opening coronary arteries early can save ischemic myocardial and reduced theforming of myocardial scar, and reduced the incidence of fQRS ECG. Through thedifferent period of myocardial reperfusion therapy, the change of the incidence fQRSfurther suggested that: new noninvasive ECG indicators----fQRS, which furtherconfirmed that the emergency PCI have the superior value compared with optional PCI.3. The fQRS on ECG in the MI patients inferred that myocardium exist the scartissue, and which had further improved the patients have the higher incidence of ventricular arrhythmias.