Plaque regression of non-culprit sites in patients with acute coronary syndrome may be associated with better long-term outcomes, according to data presented Tuesday at Scientific Sessions.
Data from prospective studies of serial intravascular ultrasound (IVUS) showed that patients who achieved both plaque regression and lower LDL cholesterol had significantly reduced risk for major adverse cardiovascular events.
“The results of this study suggest reaching both plaque regression and sufficient LDL-C lowering is clinically important in post-ACS management,” said Hirohisa Endo, MD, who presented the study. “In addition, this study shows that plaque regression determined by volumetric IVUS measurement could be a surrogate marker of future cardiovascular events.”
According to Endo, of the department of cardiovascular medicine at Juntendo University Graduate School of Medicine in Tokyo, Japan, IVUS follow-up in patients with ACS is not routinely performed. Therefore, Endo and colleagues looked at data taken from four prospective clinical trials that included patients with ACS undergoing regular IVUS of non-culprit lesions in the culprit vessel at baseline and six months follow-up.
Of all 382 patients, they excluded the patients without available serial IVUS measurements (n=150) and without statin therapy (n=59). They looked at outcomes related to percent atheroma volume (PAV), on treatment LDL cholesterol and MACE. All patients were treated with statins.
The overall change in PAV was -1.6 and plaque regression, defined as PAV change from baseline <0, occurred in 67.6 percent of patients. The rate of MACE was lower in patients with plaque regression than in those without regression, but the difference was not statistically significant (13.7 percent vs. 19.6 percent). Among those patients with plaque regression, 40.2 percent achieved on-treatment low LDL cholesterol levels.
About 40 percent of patients achieved both plaque regression and on-treatment low LDL (group 1), 27.2 percent met only plaque regression (group 2) and 32.4 percent had plaque progression with/without LDL cholesterol (group 3). A multivariate analysis showed that those patients who achieved both regression and on-treatment LDL cholesterol had a 62 percent decreased risk of MACE (HR=0.38; 95 percent CI, 0.14-0.90; P=.03).
“The growing interest in treating vulnerable plaque has substantially raised the bar on current treatment approaches and, if complemented by confirmatory imaging techniques and markers, can possibly help regress plaque evolution and eliminate the possibility of atherosclerosis altogether,” Endo said.