Predictors of Statin-Induced Regression of Left Anterior Descending Coronary Artery Wall Thickness as Measured by High-Resolution Transthoracic Echocardiography

Abstract

Statin therapy has been shown to reduce cardiovascular risk after myocardial infarction (MI). Using a novel technique of high-resolution transthoracic echocardiography (HRTTE), we sought to assess the statin-induced changes in left anterior descending coronary artery (LAD) wall thickness in previously statin naive patients over a 12-month period. Thirty subjects underwent HRTTE assessment of their LAD wall thickness predischarge post-MI (non-LAD territory) and at 3, 6, and 12 months. The LAD anterior and posterior wall thickness and vessel luminal diameter were measured. Blood lipid levels were also assessed at each study visit. All subjects were started on moderate lipid-lowering therapy (40 mg of atorvastatin or simvastatin). There was a sustained decrease in total cholesterol (-23%), triglycerides (-19%), and low-density lipoprotein (-41%) at the 3-month visit from the baseline, with no change in high-density lipoprotein level. Overall, there was no change in the LAD wall thickness and external or vessel lumen diameter over the 12-month period. Of those that demonstrated regression, the only predictor of percentage change in the LAD wall thickness was the baseline LAD wall thickness. Despite a favorable change in blood lipid profile, no overall change in the LAD wall thickness was detected over a 12-month period in subjects on moderate statin therapy using HRTTE. However, using case-based analysis, regression was able to be predicted by the baseline LAD wall thickness. HRTTE may be an instructive noninvasive modality to assess response to statin intervention.