Objectives: To demonstrate whether the improved imaging quality gained by using tissue harmonic echocardiography in place of fundamental echocardiography results in the improved risk stratification of patients presenting with non-ST-elevation acute chest pain.
Methods and results: Eighty patients with over 30 min of non-ST-elevation chest pain that had lasted less than 6 h were recruited. All patients underwent resting tissue harmonic and fundamental echocardiographic scans. Diagnosis for acute myocardial infarction was made on a 24 h creatine kinase-MB sample. Echocardiographic images were reported by two experienced blinded observers. Patients were followed up at least 4 months after admission. Endpoints included all-cause mortality, non-fatal myocardial infarction and revascularisation procedures. Tissue harmonic echocardiography allowed assessment of all myocardial segments in all patients compared to 43/78 patients ( p<0.001 ) with fundamental echocardiography. A wall thickening abnormality demonstrated on tissue harmonic echocardiography and not fundamental echocardiography was a significant predictor of index myocardial infarction on admission ( p<0.007 ) and for an adverse cardiac event during follow up ( p=0.002 ).
Conclusions: Tissue harmonic echocardiography is superior to fundamental echocardiography for accurate assessment of systolic wall thickening and hence risk stratification for patients presenting with acute chest pain and non-diagnostic electrocardiogram changes.