Keisuke Morimoto

Clinical utility of low-pressure implantation of drug-eluting stent into very small vessels

BACKGROUND Although drug-eluting stents (DES) reduce restenosis, the best strategy for DES implantation in small vessels has not been established. PURPOSE We investigated the clinical usefulness of low-pressure implantation of a 2.5-mm DES for small vessels less than 2.5mm in diameter. METHODS In 118 patients, a 2.5-mm DES was implanted for small vessels less than 2.5mm in diameter between 2007 and 2009 in our hospital. The patients were divided into two groups by initial deployment pressure: low-pressure (LP; n=46) and nominal-pressure (NP; n=72). RESULTS Patients with impaired glucose tolerance were more frequent (p=0.02) and the target vessel diameter was significantly smaller (p=0.01) in the LP group than in the NP group. A smaller minimum lumen diameter (MLD) was obtained (LP: 2.22±0.27mm vs. NP: 2.34±0.26mm, p=0.02) after DES implantation with a smaller balloon-to-artery ratio (p=0.03) in the LP group. However, at mid-term follow-up (7.7±3.9 months), MLD (p=0.55) and the binary restenosis rate (LP: 2.6% vs. NP: 11.1%, p=0.12) were not significantly different between the LP and NP groups. Furthermore, by Kaplan-Meier analysis, the incidence of major adverse cardiac events was not different between the groups during the long-term follow-up (32.4±8.6 months). CONCLUSION The present study indicates that low-pressure implantation of 2.5-mm DES for very small vessels may be feasible with regard to short- and long-term clinical outcomes.

Efficacy of Cardiac Resynchronization Therapy Performed Concomitantly with Primary Cardiac Surgery

Cardiac resynchronization therapy (CRT) improves symptoms and cardiac function in patients with heart failure and prolongs QRS duration on an electrocardiogram. However, additional effects of concomitant CRT in patients who undergo cardiac surgery are unclear. We assessed the clinical efficacy of this therapy when it is performed concomitantly with primary cardiac surgery.