Optical coherence tomography evaluation of late strut coverage patterns between first-generation drug-eluting stents and everolimus-eluting stent.

OBJECTIVES: To compare strut coverage patterns between everolimus-eluting stent (EES) and first-generation drug-eluting stents (DES) at more than 12 months after successful implantation, using optical coherence tomography (OCT). BACKGROUND: No sufficient OCT data has been reported comparing late strut coverage patterns between EES and first-generation DES. The favorable late results after EES implantation could be related to lower rates of uncovered and malapposed struts. METHODS: A total of 66 DES (21 EES, 23 SES, and 22 PES) that were implanted at least 1 year in advance in 40 patients and met good late angiographic results were evaluated by OCT. The percentage of uncovered and malapposed struts, calculated as the ratio of uncovered or malapposed struts to total struts in all cross-sectional images per stent, was compared among the three groups. RESULTS: A total of 35,061 struts were analyzed: 11,967 from EES, 11,855 from SES, and 11m239 from PES. The average tissue coverage thickness of the struts per stent was greater in EES than in SES and PES (109 ± 40 µm vs. 72 ± 27 µm and 83 ± 26 µm, respectively; P = 0.001). The percentage of uncovered struts (1.9 ± 4.1% in EES vs. 11.6 ± 12.7% in SES, P = 0.01 and vs. 7.1 ± 5.2% in PES, P < 0.001) and malapposed struts (0.1 ± 0.3% in EES vs. 1.8 ± 3.5% in SES, P = 0.01 and vs. 3.5 ± 5.1% in PES, P = 0.02) was much lower in EES than in first-generation DES, with no significant differences between SES and PES. CONCLUSIONS: Late strut coverage patterns are not similar between EES and first-generation DES. EES showed a lower percentage of uncovered and malapposed struts.

Usefulness of transesophageal echocardiography during implantation of the CoreValve percutaneous aortic prosthesis: influence of the learning curve.

BACKGROUND AND OBJECTIVES: The purpose of this study was to evaluate the usefulness of transesophageal echocardiography during the implantation of the CoreValve percutaneous aortic prosthesis and the influence of the learning curve in its indications. METHODS: From April 2008 to January 2010, 53 patients were treated for symptomatic severe aortic stenosis with a CoreValve percutaneous aortic prosthesis. Transesophageal echocardiography was performed during the procedure for two reasons: if a discrepancy between the measures of the aortic annulus arose before the implantation and to provide visualization if a complication occurred during the procedure. Patients were divided in to two groups based on the learning curve (group I:the first 25 patients, group II: all of the subsequent patients). RESULTS: Thirty-six transesophageal echocardiographies were performed on 28 patients (53%).In 15 cases the indication was to assist us in determining the proper sized prosthesis, and in the other 21 cases it was performed due to a complication during the procedure. The numbers of intraprocedure transesophageal echocardiographies were similar in both learning-curve groups, (64% in group I vs. 71% in group II, P = 0.56) but the proportion of the studies indicated by serious complications was significantly lower in the second period of the learning curve (67% in group I vs. 17% in group II, P < 0.05). CONCLUSIONS: In our experience, transesophageal echocardiography was very useful in more than one-half of the patients during the implantation of the CoreValve percutaneous aortic prosthesis. After overcoming the learning curve, its indication due to serious procedure-related complications decreased significantly.