Changes of electrocardiogram J wave in patients with acute myocardial infarction in super-acute phase

Abstract

Objective To analyze the clinical significance and prognosis of the electrocardiogram with or without J wave in patients with acute myocardial infarction in super-acute phase.Methods The clinical data of 90 patients with acute myocardial infarction in our hospital in recent five years were retrospectively analyzed.According to the electrocardiogram,the patients were divided into J wave group of 25 patients (27.8％),and no J wave group of 65 patients (72.2％).The incidence rate of ventricular arrhythmias,the sudden death rate and left ventricular ejection fraction (LVEF) between the two groups were compared.Results In J wave group,17 cases (68.0％) occured ventricular arrhythmia,no J wave group has 27 cases (41.5％),the ventricular arrhythmia incidence was higher in J wave group (P ＜ 0.05).J wave group had 2 cases(8.0％) of sudden death,no J wave group had 2 cases (3.1％),the sudden death rate of J wave group was significantly higher than that of no J wave group (P ＜ 0.05).The LVEF was(48.9 +8.1)％ in J wave group and (51.7 +7.8)％ in no J wave group,there was no significant difference between J wave group and no J wave group in prognosis of LVEF (P ＞0.05).Conclusions The electrocardiogram of acute myocardial infarction in the super-acute phase can appear J wave,can also be no J wave,but no J wave is more common.J wave indicates ECG activities has more instability,and more prone to ventricular arrhythmia,and leads to a higher incidence of sudden cardiac death,but has no significant influence on prognosis of cardiac function. Key words: Acute myocardial infarction ; Super-acute phase ; Electrocardiogram ; Ischemic J wave