Functional Recovery After Coronary Artery Bypass Grafting in Patients With Severe Left Ventricular Dysfunction and Preserved Myocardial Viability in the Left Anterior Descending Arterial Territory as Assessed by Thallium-201 Myocardial Perfusion Imaging

Abstract

he prognosis of patients with coronary artery disease and severe left ventricular (LV) dysfunction is poor, unless significant functional recovery is gained with coronary revascularization to viable myocardium. [1][2][3][4][5][6][7][8] The purpose of the present study was to evaluate the clinical significance of myocardial viability in the territory supplied by the left anterior descending artery (LAD) in patients with severe LV dysfunction (ejection fraction (EF) ≤35%) who underwent coronary artery bypass grafting (CABG), because the prognostic and procedural significance of CABG to the LAD coronary artery was underscored recently. 9-11 Methods Study PatientsOne hundred consecutive patients, all who demonstrated of having myocardial viability in the LAD territory and who undergone CABG (66 men, 34 women, aged 42-85 years [mean, 66]) were studied retrospectively. Previous myocardial infarction and CABG had occurred in 66 and 3 patients, respectively. Left main coronary artery disease was found in 31 patients, 3-vessel disease in 44, 2-vessel disease in 23, and 1-vessel disease in 2. Written informed consent was obtained from all of the patients. EchocardiographyEchocardiographms were performed using a Toshiba SSH-65A (Tokyo, Japan) or an Aloka SSD-710 (Tokyo, Japan) with 2.5-3.75 MHz transducers. A complete Mmode and 2-dimensional study were performed and recorded on video tape for subsequent analysis. LV segmental wall motion abnormality and systolic wall thickJpn Circ J 1999; 63: 752 -758 (Received May 6, 1999; revised manuscript received June 24, 1999; accepted July 5, 1999 To evaluate the functional recovery after coronary bypass surgery in patients with severe left ventricular (LV) dysfunction (ejection fraction (EF) ≤35%), 100 consecutive patients with viable myocardium in the territory supplied by the left anterior descending artery (LAD) underwent coronary bypass grafting. In addition, cardiac catheterization and single-photon emission computed tomography (SPECT) perfusion imaging with thallium-201 were repeated 1-year postoperatively. Although 12 patients with severe LV dysfunction were preoperatively in a worse New York Heart Association functional class (3.1±0.7 vs 2.4±0.8; p<0.01), had a higher incidence of heart failure (10/12 vs 14/88; p<0.001) and had a worse LVEF (29±5 vs 61±14%; p<0.001) compared with 88 patients without severe LV dysfunction, the operative mortality was similar in the 2 groups (1/12 vs 2/88; p=NS). The postoperative NYHA functional class in the patients with severe LV dysfunction was similar to that in the patients without such dysfunction (1.6±0.7 vs 1.3±0.6; p=NS). In addition, the 1-year postoperative study revealed a significant improvement in the thallium defect score in both the LAD territory (1.7±1.2 to 0.7±1.0, p=0.01) and all the territories (5.2±2.2 to 3.2±1.9, p=0.002) in patients with severe LV dysfunction, whereas no improvement in defect score was found in either of these territories in those without severe LV dysfunction (LAD: 0.6±1.4 to 0.4±1.2, p=NS; All: 1.9±...

Assessment of Myocardial Viability in Ischemic Cardiomyopathy With Reduced Left Ventricular Function Undergoing Coronary Artery Bypass Grafting

“…Evidence of viability in the LAD territory warrants the use of a left internal mammary artery‐to‐LAD graft for optimal benefits and provides a justification against the risks of CABG, especially in patients with longer life expectancy. A study [ 48 ] using thallium‐201 SPECT perfusion imaging indicated that in patients with severe LV dysfunction (LVEF ≤ 35%), myocardial viability in the LAD territory predicts a significant postoperative improvement in functional class and LVEF of at least 10% or more after CABG with severe LV dysfunction. Yang et al [ 22 ] agree that the number of scar segments, total scar score, and the number of scar segments in LAD territory correlated very well with LVEF after CABG.…”

Long-Term Outcome of a Residual Scar From Myocardial Infarction After Coronary Artery Bypass Grafting. A 100-Month Study Using Myocardial Perfusion Scintigraphy.

“…Chikamori et al reported that myocardial viability observed on 201 Tl SPECT perfusion imaging predicts a significant improvement in left ventricular (LV) function after CABG in patients with severe LV dysfunction. 16 Tamaki et al reported a high concordance for the stress perfusion scores between the 2 radiopharmaceuticals; reversible perfusion abnormalities were similar between stress-rest tetrofosmin and stress-delayed 201 Tl studies. 17 Stress tetrofosmin perfusion tomography is a valuable method for detecting CAD and assessing tissue viability, with an accuracy similar to that of stress 201 Tl tomography.…”

Prognostic role of single-photon emission computed tomography (SPECT) imaging in myocardial viability

“…Chikamori et al [59] followed 100 patients, all of whom had left anterior descending territory viability, by 201 Tl stressinjection or rest-redistribution. The majority of these patients had left main or three-vessel disease.…”