Valsartan for Suppression of Plaque Volume and Restenosis After Drug-Eluting Stent

Stimulation of the angiotensin II type 1 (AT1) receptors after arterial injury promotes vascular smooth muscle cell (VSMC) migration, proliferation, and extracellular matrix production, leading to the hope that blockade of this receptor by angiotensin-converting enzyme inhibitors (ACEI) or specific (AT1) receptor antagonists (ARBs) might reduce intimal hyperplasia. However, despite confirmatory evidence in several animal models of restenosis, the large scale MERCATOR and MARCATOR trials of cilazapril with balloon angioplasty failed to show benefit. In 1999, Kondo reported the results of a randomized pilot trial of 100 patients who received Palmaz-Schatz stents and were randomized to receive the ACE inhibitor quinapril or placebo. The volume of neointimal hyperplasia assessed by IVUS was significantly less quinapril than the control group (18 ± 0.6 mm3 vs. 25 ± 0.6 mm3; p \< 0.05). The quinapril group's restenosis rate was 16%, with the quinapril benefit being observed only in patients with the D/D and I/D genotypes. Also, other study reported on a consecutively treated cohort of 1,598 stented patients, noting that ACE inhibitor usage at the time and after stenting reduced the risk of subsequent revascularization dramatically (adjusted odds ratio, 0.46; p = 0.001). In the ValPREST trial which is a single-center randomized trial of patients receiving stents for type B2/C lesions, comparing valsartan (and ARV) 80 mgs daily with open treatment, patients randomized to valsartan had a 19% incidence of restenosis compared with 39% in the open treatment arm (p = 0.005).

Recently, several randomized studies were conducted to compare the safety and efficacy of the two leading drug-eluting stent (DES). However, data on the association of ARBs for suppression of neointimal hyperplasia are limited in the DES era. Therefore, a pivotal randomized study is warranted.