Ultrasonic tissue characterization in acute coronary syndromes.

BACKGROUND: Ultrasonic tissue characterization (UTC), as evaluated through integrated backscatter, has the potential to detect precocious structural damage to myocardial tissue. In acute coronary syndromes (ACS) this technique is attracting attention due to its potential to evaluate myocardial viability.

OBJECTIVE: To evaluate the role of UTC in the emergency department.

METHODS: We studied 28 individuals, classified in three groups: Group I (13; 52.2+/-15.5 years) with patients admitted with chest pain who have negative evaluation for acute coronary syndrome; Group II (9; 54.2+/-10.0 years) with acute myocardial infarction in right coronary artery territory; and Group III (6; 62.1+/-9.1 years) with acute myocardial infarction in the anterior descendent branch territory. For each individual, we analyzed four segments in the short axis view at the papillary muscle level (1--anterior; 2--anterior-lateral; 3--inferior e 4--septal), for the following parameters: corrected coefficient, amplitude, delay index and IBS pattern.

RESULTS: The acute myocardial isquemic process in its initial phase was not detected by the corrected coefficient or by the IBS amplitude. The sincronicity parameters (delay index and IBS pattern), more sensible, were partially able to identify changes in more extension regions of myocardial infarction.

CONCLUSION: More studies should be conducted to evaluate these parameters in the early phase of acute coronary syndromes.