Yasushi Ueki

Optical coherence tomography- vs . intravascular ultrasound-guided percutaneous coronary intervention

Coronary angiography is routinely used to guide percutaneous coronary interventions (PCI) despite obvious limitations of this lumen based approach. Intravascular imaging including intravascular ultrasound (IVUS) and optical coherence tomography (OCT) represent two techniques that provide essential information on pre-procedural lesion characteristics (i.e., lesion severity, landing zone, and plaque composition) and the result after stent implantation (i.e., stent expansion and eccentricity, strut apposition, lesion coverage, tissue protrusion, and dissections).

Progression of cardiac allograft vasculopathy assessed by serial three-vessel quantitative coronary angiography

Background The purpose of the present study was to assess the short- and long-term progression of cardiac allograft vasculopathy (CAV) using serial 3-vessel quantitative coronary angiography (QCA). Methods CAV progression was assessed using serial 3-vessel QCA analysis at baseline, 1-year and long-term angiographic follow-up (8.5±3.7 years) after heart transplantation. The change in minimal lumen diameter (MLD) and percent diameter stenosis (%DS) was serially assessed within matched segments. Patients were graded according to the ISHLT-CAV classification and grouped as ISHLT-CAV0 and ISHLT-CAV1-3. The primary endpoint was mean change in MLD and %DS. Results A total of 41 patients and 520 matched segments were available for serial 3-vessel QCA. Overall, MLD decreased non-significantly from baseline to 1-year follow-up and significantly from 1-year to the long-term angiographic follow-up (Δ-0.08mm/year [95%CI -0.11 to -0.05], P<0.001). %DS increased significantly from baseline to 1-year (Δ+0.96%/year [95%CI 0.04 to 1.88], P = 0.041) and from 1-year to long-term angiographic follow-up (Δ+0.61%/year [95%CI 0.33 to 0.88], P<0.001). ISHLT-CAV1-3 at 1 year and at long-term angiographic follow-up was observed in 22% and 61%, respectively. Between baseline and long-term angiographic follow-up, a significant reduction in MLD was observed within both groups without a significant difference in the reduction between the two groups (ISHLT-CAV0: median -0.49mm [IQR -0.54 to -0.43] vs. ISHLT-CAV1-3: median -0.40mm [IQR -0.44 to -0.35], P = 0.4). Conclusion The current data suggest that QCA can’t predict CAV beyond 1 year, but, QCA affirmed that CAV progresses to a similar extent in patients who do not develop visual CAV during long-term follow-up.

Long-Term Assessment of Bioresorbable Coronary Scaffolds: Disappearing Stents, Reappearing Atherosclerosis

SEE PAGE 1882 A lthough drug-eluting stents (DES) improved the overall safety and efficacy of percutaneous coronary intervention (PCI), late device failures, including in-stent restenosis and stent thrombosis, continue to occur at relatively low, yet constant rates (1). Whereas neointimal hyperplasia and smooth muscle cell proliferation were the prevailing concerns in the era of bare-metal stents, neoatherosclerosis, the development of a de novo atherosclerotic plaque overlying a coronary stent, is increasingly recognized as pathobiological substrate underlying late stent failures (Figure 1). Histologically, the hallmark of in-stent neoatherosclerosis is the accumulation of lipid-laden macrophage foam cells in the neointimal tissue of the stented segment, with or without necrotic core formation or calcification within the neointima (2). Neoatherosclerosis is an accelerated process compared with atherosclerosis in native vessels, and its time course appears to be affected by implanted device type (3). Bioresorbable vascular scaffolds (BVS) that only temporarily scaffold the diseased coronary segment followed by full biodegradation were developed to overcome longterm shortcomings of metallic stents, with further potential advantages, including restoration of coronary vasomotion, positive vessel remodeling, protective sealing of atherosclerotic plaques, and facilitated

ST-Segment Elevation Myocardial Infarction Due to Optical Coherence Tomography-Detected Coronary Artery Compression Following Supravalvular Pulmonary Artery Patchplasty 18 Years After Switch Procedure

An 18-year-old man underwent correction of a supravalvular pulmonary artery (PA) stenosis after neonatal correction of a dextrotransposition of the great arteries by a switch procedure. The coronary pattern presented with a common ostium for the left anterior descending artery and right coronary

Angiographic derived endothelial shear stress: a new predictor of atherosclerotic disease progression

AIMS To examine the efficacy of angiography derived endothelial shear stress (ESS) in predicting atherosclerotic disease progression. METHODS AND RESULTS Thirty-five patients admitted with ST-elevation myocardial infarction that had three-vessel intravascular ultrasound (IVUS) immediately after revascularization and at 13 months follow-up were included. Three dimensional (3D) reconstruction of the non-culprit vessels were performed using (i) quantitative coronary angiography (QCA) and (ii) methodology involving fusion of IVUS and biplane angiography. In both models, blood flow simulation was performed and the minimum predominant ESS was estimated in 3 mm segments. Baseline plaque characteristics and ESS were used to identify predictors of atherosclerotic disease progression defied as plaque area increase and lumen reduction at follow-up. Fifty-four vessels were included in the final analysis. A moderate correlation was noted between ESS estimated in the 3D QCA and the IVUS-derived models (r = 0.588, P < 0.001); 3D QCA accurately identified segments exposed to low (<1 Pa) ESS in the IVUS-based reconstructions (AUC: 0.793, P < 0.001). Low 3D QCA-derived ESS (<1.75 Pa) was associated with an increase in plaque area, burden, and necrotic core at follow-up. In multivariate analysis, low ESS estimated either in 3D QCA [odds ratio (OR): 2.07, 95% confidence interval (CI): 1.17-3.67; P = 0.012) or in IVUS (<1 Pa; OR: 2.23, 95% CI: 1.23-4.03; P = 0.008) models, and plaque burden were independent predictors of atherosclerotic disease progression; 3D QCA and IVUS-derived models had a similar accuracy in predicting disease progression (AUC: 0.826 vs. 0.827, P = 0.907). CONCLUSIONS 3D QCA-derived ESS can predict disease progression. Further research is required to examine its value in detecting vulnerable plaques.

Late lumen loss in the era of new generation drug-eluting stents: perspective on a quarter century companion

Implantation of coronary stents has become one of the most frequently performed interventional medical procedures, not least because its efficacy was substantially improved by the introduction of drug eluting stents (DES). Target lesion revascularization (TLR), defined as a repeat intervention (i.e. percutaneous coronary intervention or coronary artery bypass graft surgery) due to restenosis within the stent (or its edge), has been used as the most common clinical endpoint of stent efficacy. Current metallic DES technology has demonstrated an outstanding reduction of TLR compared with bare metal stents (3 vs. 12%, number needed to treat 10). The low incidence of TLR requires a large sample size to secure sufficient statistical power for the evaluation of new devices (i.e. to prove noninferiority compared to current standard devices). For this reason, several continuous angiographic measures obtained by quantitative coronary angiography analysis (QCA) such as minimal lumen diameter (MLD), diameter stenosis (DS), and late lumen loss (LLL) have been investigated as a surrogate marker of TLR. LLL, defined as MLD at post-procedure minus MLD at follow-up, has a particular ability to quantify the degree of neointimal hyperplasia independent of procedural variables (i.e. reference vessel diameter and residual stenosis) (Take home figure). One-quarter of a century ago, LLL was reported by Dr Kuntz to evaluate the efficacy of balloon angioplasty and metallic stents. Since then, LLL has been studied intensively for bare metal stents and first-generation DES, and has unquestionably achieved a gold standard status for assessing metallic stent efficacy. However, the prognostic value of LLL obtained by serial angiography for predicting repeat interventions has not been evaluated in the era of contemporary DES, representing a relevant gap in the field of interventional vascular medicine. In this issue of the European Heart Journal, Asano et al. report the results of a patient-level meta-analysis of seven randomized controlled trials including 2426 patients treated with firstand second-generation DES, and a study-level meta-analysis of 40 studies including 19 199 patients treated with Conformité Européene-mark DES. In the patient-level analysis, the optimal LLL cut-off value for predicting TLR occurring at 2 years amounted to 0.50 mm (sensitivity 0.67, specificity 0.84) and this cut-off was confirmed as the best independent predictor of TLR [adjusted HR 6.6, 95% confidence interval (CI) 4.7–9.4]. The authors added a meta-regression analysis to demonstrate the validity of the derived LLL cut-off. The pooled mean value of LLL amounted to 0.23 mm (95% CI 0.20–0.26), confirming the high efficacy of today’s DES, and there was a moderate correlation between 1 and 5 year TLR rate and lesions with LLL > 0.50 mm (R = 0.44 at 1 year and R = 0.40 at 5 years). The essential value of this study lies in the derivation of the 0.50 mm threshold as a reasonably good independent marker for predicting future TLR in the era of new-generation DES. These findings are best summarized in Figure 1 of the author’s article. Several limitations should be noted in the current study. First, both patientand study-level analysis included a notable proportion of first-generation DES (1533/2426 patients), which are irrelevant for current practice. Second, analysis according to stent diameter, reportedly a strong confounding factor of TLR, was not conducted. Third, some TLRs were unavoidably driven by the occulo-stenotic reflex during follow-up angiography and may not have been based on objective criteria of ischaemia, despite independent event adjudication and application of the universal definition. Reassuringly, the predictive value of a > 0.50 mm LLL remained robust following a sensitivity analysis excluding TLRs that were eventually related to the routine angiographic followup. Finally, one should be aware about the selected population, in which serial angiography was performed. LLL has several advantages as a study endpoint in patients treated with metallic DES: (i) it is a highly reproducible measure that can be assessed by any QCA-trained person; (ii) the basis is angiography and