Associations between ECG changes and echocardiographic findings in patients with acute non-ST elevation myocardial infarction.

BACKGROUND: ST segment depression (STD) and T wave inversion (TWI) are typical electrocardiographic (ECG) findings in non-ST elevation myocardial infarction (NSTEMI). In ST elevation myocardial infarction, ST changes represent transmural ischemia. The pathophysiological mechanisms of the ECG changes in NSTEMI are unclear.

PURPOSE: We studied the associations between ECG and the echocardiographic findings in NSTEMI patients.

METHODS: Twenty patients with acute NSTEMI were recruited during their hospital stay. A comprehensive echocardiography study was performed. The findings were compared with blinded ECG analyses.

RESULTS: Nine (45%) patients had STD, and 16 (85%) patients had TWI. In multivariable analysis, STD was independently associated with a lower global early diastolic strain rate (β=-5.061, p=0.033). TWI was independently associated with lower circumferential strain (β=0.132, p=0.032).

CONCLUSIONS: The typical ECG changes in NSTEMI patients were associated with subtle echocardiographic changes. STD was related to changes in diastolic function, and TWI was associated with systolic deterioration.