Clinical Significance of Precordial ST Segment Depression in Acute Inferior Myocardial Infarction

Joen, Dae Jin; Bae, Jun Ho; Hong, Gu Roo; Park, Jong Seon; Shin, Dong Gu; Kim, Young Jo; Shim, Bong Sub

Abstract

BACKGROUNG AND OBJECTIVES: To evaluate the clinical and prognostic significance of precordial ST segment depression in precordial leads on admission electrocardiogram (ECG) in acute inferior myocardial infarction treated with intravenous thrombolytic therapy. We analysed about clinical and angiographic characters. MATERIALS AND METHOD: ECG findings in 50 patients with acute inferior myocardial infarction were retrospectively studied with results of coronary angiography and clinical informations. We classified all patients in two group according to the admissional ECG. Twenty nine patients (Group A) had no or <1.0 mm ST depression in precordial lead and Twenty one patients (Group B) had > or =1.0 mm ST depression in two or more precordial (V1-V6) leads were included in this group.
RESULTS
In precordial ST segment depression in acute inferior myocardial infarction patients had higher plasma peak mean CK levels (1945+/-1419 vs 3547+/-2728 IU/L, p=0.027) and lower LV ejection fraction (62+/-10% vs 53+/-11%, p=0.008) and lower left ventricle global chordal shortening (0.89+/-0.71 vs -1.39+/-0.94, p=0.046) and inferior wall chordal shortening (-1.68+/-1.11 vs -2.43+/-0.74, p=0.014) and higher Killip class (1.3+/-0.8 vs 2.4+/-1.4, p=0.002) than without precordial ST segment depression patients.
CONCLUSION
In conclusion acute inferior myocardial infarction with precordial ST depression patients had more extensive myocardial damage with global and inferior left ventricle severe wall motion dysfunction. Therefore, this suggests a worse prognosis in acute inferior myocardial infarction with precordial ST depression than without precordial ST depression patients. We need more aggressive diagnosis and treatment in this patients to prevent extending myocardial damage.