Variations of electrocardiographic parameters during hospitalization predict long‐term outcomes in patients with non‐ST‐segment elevation myocardial infarction

BACKGROUND: Electrocardiogram is an essential modality for diagnosis and early risk stratification for patients with acute coronary syndrome (ACS), but its long-term prognostic value has not been well studied. This study tried to investigate the long-term prognostic value of variations of ECG parameters at admission and discharge in patients with non-ST-segment elevation myocardial infarction (NSTEMI). METHODS: A total of 170 NSTEMI patients were recruited consecutively from 2013 to 2014 in West China Hospital of Sichuan University. All subjects' ECGs at admission and discharge were reviewed. Follow-up was performed, and the survival difference between groups was analyzed. RESULTS: Comparing with at admission, NSTEMI patients at discharge with a wider P wave (19.4% vs. 8.1%, p = 0.047), with new-onset PtfV1 positive (31.2% vs. 8.1%, 11.5%, 13.3%, p = 0.147) and with a greater number of leads showing ST depression (21.9% vs. 10.3%, p = 0.037) were prone to MACEs during long-term follow-up. The independent risk factors for the primary endpoints determined using a multivariate cox regression were new-onset PtfV1 positive during hospitalization (HR = 4.705, 95% CI = 1.457-15.197, p = 0.010) and prolonged QRS duration at discharge comparing to admission (HR = 2.536, 95% CI = 1.057-6.083, p = 0.030), besides diabetes mellitus, stage 3 hypertension, and multiple vessel lesions. CONCLUSION: Discharge ECG with new-onset PtfV1 positive and prolonged QRS duration were independent risk factors for recurrence of MACEs in NTEMI patients. The differences of ECG parameters between at admission and discharge, including P-wave duration, number of leads with ST-segment depression, carried long-term prognostic information for NSTEMI patients.