Prediction of Functional Recovery of the Left Ventricle After Coronary Revascularization in Patients With Prior Anterior Myocardial Infarction. A Myocardial Integrated Backscatter Study.

Abstract

n some patients with chronic coronary artery disease, persistent left ventricular (LV) dysfunction can be restored by coronary revascularization. Thus, identifying potentially reversible dysfunction has important therapeutic and prognostic implications. Recently, it was reported that the cyclic variation (CV) of integrated backscatter (IBS), which reflects intrinsic contractile performance, 1-6 can predict myocardial viability in patients with reperfused acute myocardial infarction (MI), 7 but this method has not been validated for chronic LV dysfunction. [8][9][10] The purpose of this study was, therefore, to determine whether IBS could identify hibernating myocardium and predict LV functional recovery after coronary revascularization in patients with a remote anterior MI. Circulation Journal Vol.66, October 2002 Methods Selection of PatientsBetween November 1996 and October 1998, 255 patients with angiographically proven coronary artery disease underwent a coronary revascularization procedure and from this group, we prospectively selected 17 patients who met the following inclusion criteria: (1) technically adequate echocardiographic studies allowing the region of interest (ROI) for IBS analysis to be placed in the anterior myocardium that did not include apparent scar formation (wall thickness <5 mm and/or increased acoustic reflectance of the wall compared with the pericardium); (2) remote MI, the onset of which was more than 1 month before the revascularization procedure (48±20 days, range: 29-102); (3) single-vessel coronary artery disease (only the left anterior descending artery), >75% narrowing in diameter on coronary angiography; (4) persistent LV dysfunction (ejection fraction (EF) <50% on angiography); (5) successful revascularization procedure; and (6) stable clinical condition with no major clinical events during the follow-up period (ie, death, reinfarction, coronary bypass surgery or interventional revascularization). Cyclic variation (CV) of myocardial integrated backscatter (IBS), which reflects intrinsic contractile performance, can predict myocardial viability in patients with a reperfused acute myocardial infarction (MI), but the use of this method has not been validated for chronic left ventricular (LV) dysfunction. The aim of this study was to examine whether myocardial IBS was useful for predicting LV functional recovery after coronary revascularization in 17 patients with prior anterior MI and LV dysfunction (ejection fraction <50%). Within 24 h of the revascularization procedure (percutaneous transluminal coronary angioplasty or coronary stenting), IBS curves were obtained by placing the region of interest on the anterior wall on the short-axis IBS image. The patients had repeat left heart catheterization at 3 or 6 months after the revascularization procedure, and were grouped according to the patterns of the IBS curve within the anterior wall. In 8 patients (group A), the IBS curve had a synchronized pattern with the magnitude of CV ≥3.5, and in the remaining 9 patients (group B), the ...

Caracterização tecidual ultra-sônica em síndromes coronarianas agudas

“…Scar delimitation with deposition of collagen requires a time period longer than four weeks of delay between the onset of symptoms and assessment. Since inclusion criteria in the present study required the absence of previous ischemic events or of any other factors that would involve myocardial structural damage -such as diabetes mellitus -nondifferentiation between the groups was not unexpected, and is in agreement with studies published elsewhere [8][9][10][15][16][17] . IBS variation amplitude changes are reported much earlier, and are more easily subject to documentation due to their ultrasonic tissue characterization.…”

“…In addition to IBS variability, changes in pattern or delay are documented and considered more sensitive, and stand as a possibility for the purpose of predicting the viability of injured myocardial tissue 9,10,12,[15][16][17][18][19][20][21] . Such phenomenon has been investigated through techniques that are not available in the equipment used in the present study.…”

“…The analysis of synchronicity parameters (delay index and pattern) has been attractive from its potential to identify myocardial viability 9,10,12,[15][16][17][18][19][20][21] . In the present study such analysis was limited to echocardiographic assessment of ventricular segmental motility recovery at rest.…”

“…It has been proven the ability to identify changes in different models of chronic cardiopathy, and even the potential for subclinical detection of structural damage 4,5 , such as diabetes mellitusinduced myocardiopathy 6,7 . IBS has also been studied in the acute coronary syndrome (ACS) scenario, where major interest is its potential to identify myocardial viability [8][9][10] . However, its technical evaluation in the emergency room scenario -the objective of the present study -is hardly ever explored.…”

Early Detection of Doxorubicin-Induced Myocardial Damage by Ultrasound Tissue Characterization With Integrated Backscatter

“…The cyclic variation of integrated backscatter (CV-IBS) decreases with myocardial cell injury, a property that assists in detecting subclinical myocardial damage. [15][16][17][18][19][20] In the current study, we measured the acoustic properties of the myocardium in patients with normal left ventricular contractile function who were receiving DXR to determine the feasibility of using CV-IBS for detecting an early phase of DXR-induced myocardial damage.…”