Time course of vascular response after an a priori strategy of bare metal stent implantation post-dilated with a paclitaxel-coated balloon: Implementation of a three-dimensional analysis algorithm with optical coherence tomography

Background: An a priori combined therapy of a bare metal stent post-dilated with a paclitaxel- -coated balloon (PCB) was investigated with optical coherence tomography (OCT) at 2 and 6 months regarding vessel response. Previous studies have shown inconsistent results and the time course of vessel healing after such an interventional strategy is unknown. Methods: Thirty-three de novo lesions in 32 patients were electively treated. Six-month OCT analysis was available in 24 lesions. Two-month OCT follow-up was obtained in 16 lesions. Sequential OCT at 2 and 6 months was available in 7 patients. A novel 3-dimensional picture of vessel segments as spread outs was implemented. Results: Severe incomplete stent apposition (ISA) accompanied by significantly lower strut coverage were found at 2-month compared with 6-month follow-up (ISA struts: 11.4 ± 11.8% vs. 1.8 ± 4.8%, p = 0.001; uncovered struts: 14.5 ± 14.8% vs. 2.0 ± 5.3%, p = 0.001). ISA size diminished over time and the possibly observed phenomenon of positive vessel remodeling (remodeling volume: 4.9 ± 5.9 mm3 at 2-months vs. 2.0 ± 2.6 mm3 at 6-months; p = 0.042) was largely reversible in most lesions. Conclusions: Bare metal stenting with adjunctive application of paclitaxel by a coated bal­loon shows transient severe incomplete strut apposition, most likely due to focal positive ves­sel remodeling. Thus, caution is needed in bailout situations following a PCB angioplasty. A novel illustration of OCT parameters as “carpet views” enables a comprehensive analysis of investigated stents.

Abstract 2688: Can Stress Echocardiography With Tissue Characterization Evaluate Noncritical Coronary Stenosis? A Validation Study Against Simultaneous Measurement of Fractional Flow Reserve

Aim of this study was to evaluate the ability of different echocardiographic modalities to detect myocardial ischemia due to non-critical coronary stenosis, compared to the fractional flow reserve (FFR) as gold standard. Material and Methods: We investigated 22 consecutive patients presenting with stable angina, negative exercise tests and coronary 1-vessel disease with 50–75% diameter stenosis. TDE/SRI was performed at baseline and at peak hyperemia during 0.14 mg/kg/min adenosine infusion simultaneously with intracoronary FFR measurements. Angioplasty was carried out if FFR &lt; 0.75, repeating TDE/SRI during first balloon inflation. Visual wall motion score, peak systolic values for myocardial velocity (Vs), strain rate (SRs), strain (Ss) and peak overall strain (Smax) were determined in the region of interest. Postsystolic shortening (PSS), accepted as typical marker of acute myocardial ischemia, was defined as (Smax-Ss)/Smax &gt; 0.3, with reduced Ss &lt; 15%. Results: Pathologic FFR &lt; 0.75 was found in 11 patients (Table 1 ), who underwent angioplasty. Myocardial contractility reflected by SRs increased during hyperemia only in the patient group with FFR &gt; 0.75 and decreased markedly during balloon inflation. Hyperemic SRs variation correlated with FFR (r = 0.5, p = 0.018) and predicted significantly pathologic FFR with an area under ROC curve of 0.86 (p &lt;0.01). PSS was identified in 10 of 11 patients during vessel occlusion, but had a low sensitivity (2 of 11 patients with FFR &lt; 0.75) for the more subtle changes during hyperemia. Conclusion: Functional assessment of moderate-to-severe coronary stenosis remains a diagnostic challenge. PSS occurrence cannot serve as a reliable noninvasive alternative to FFR. However, the blunted hyperemic variation of systolic strain rate was able to predict a pathologic FFR, even in this small group of patients. Therefore, TDE/SRI emerges as a promising tool to enhance the diagnostic accuracy of adenosine stress echocardiography. Table 1 </jats:p