J Wave and Cardiac Death in Inferior Wall Myocardial Infarction

Abstract

Background: Clinical significance of J-wave in patients with myocardial infarction (MI) has not been well elucidated. We hypothesized that existence of J-wave in inferior leads and/or its reciprocal wave in leads V1–3 is associated with poor prognosis in patients with inferior wall MI. Methods: Total 327 patients with inferior wall acute MI (AMI) who underwent coronary intervention were analysed. First, the ECGs obtained 1 day after AMI were categorized into two groups (J-wave group and the control group) according to the J-wave: inferior leads only (n=24) or negative J-wave in V1–V3 only (n=6), and the control group (n=297). Second, High amplitude group (H-amp group: J point elevation or nJ depression more than 2 mV, n=14) was compared with Non-H group (non-high amplitude group, n=313). The primary and secondary end point was cardiac death and all-cause mortality. Results: Total 30 patients died and among them 20 were from cardiac causes. Although all-cause mortality was significantly different between groups with J-waves group and the control group (p=0.005), cardiac mortality had no significant difference (p=0.234). When compared between H-amp group and the Non-H group, there was a significant difference in all-cause mortality (p=0.015), and cardiac mortality (p=0.041). Conclusion: Presence of high amplitude J-wave in inferior leads and/or its reciprocal wave in leads V1–3 is a possible prognostic factor of all-cause and cardiac mortality in patients with inferior wall AMI.