SYNTAX score in relation to intravascular ultrasound and near-infrared spectroscopy for the assessment of atherosclerotic burden in patients with coronary artery disease.

AIMS: The aim of this study was to examine the relationship between the anatomical SYNTAX score (SXscore), derived from all three coronary arteries, and coronary wall pathology measured by radiofrequency intravascular ultrasound (RF-IVUS) and near-infrared spectroscopy (NIRS) in a single non-culprit segment. METHODS AND RESULTS: In patients referred for coronary angiography (N=88) or PCI (N=592) for stable angina or acute coronary syndrome, the SYNTAX score calculator (www.syntaxscore.com) was used to determine the SXscore before PCI, if applicable. RF-IVUS and/or NIRS were performed in a non-stenotic 40 mm study segment following the clinically indicated angiography/PCI. After adjustment for multiple confounders, a higher SXscore was associated with higher segmental plaque volume in the study segment (2.21 mm3 per SXscore point, 95% CI: 0.92-3.50, p-value 0.001), as well as with higher volume of fibrous (0.93 mm3 per point) and fibro-fatty tissue (0.29 mm3 per point). A higher SXscore was also associated with a higher NIRS-derived lipid core burden index (LCBI) in the full study segment (1.35 units per SXscore point, 95% CI: 0.22-2.47, p-value 0.019). Importantly, SXscore correlated with the fatty/fibro-fatty and LCBI signals despite adjusting for plaque burden. CONCLUSIONS: In patients with CAD, higher SXscores are associated with higher atherosclerotic burden as assessed by RF-IVUS and NIRS in a single non-stenotic coronary artery segment.

Repeatability Assessment of Intravascular Polarimetry in Patients.

Intravascular polarimetry with polarization sensitive optical frequency domain imaging (PS-OFDI) measures polarization properties of the vessel wall and offers characterization of coronary atherosclerotic lesions beyond the cross-sectional image of arterial microstructure available to conventional OFDI. A previous study of intravascular polarimetry in cadaveric human coronary arteries found that tissue birefringence and depolarization provide valuable insight into key features of atherosclerotic plaques. In addition to various tissue components, catheter and sample motion can also influence the polarization of near infrared light as used by PS-OFDI. This paper aimed to evaluate the robustness and repeatability of imaging tissue birefringence and depolarization in a clinical setting. 30 patients scheduled for percutaneous coronary intervention at the Erasmus Medical Center underwent repeated PS-OFDI pullback imaging, using commercial imaging catheters in combination with a custom-built PS-OFDI console. We identified 274 matching cross sections among the repeat pullbacks to evaluate the reproducibility of the conventional backscatter intensity, the birefringence, and the depolarization signals at each spatial location across the vessel wall. Bland-Altman analysis revealed best agreement for the birefringence measurements, followed by backscatter intensity, and depolarization, when limiting the analysis to areas of meaningful birefringence. Pearson correlation analysis confirmed highest correlation for birefringence (0.86), preceding backscatter intensity (0.83), and depolarization (0.78). Our results demonstrate that intravascular polarimetry generates robust maps of tissue birefringence and depolarization in a clinical setting. This outcome motivates the use of intravascular polarimetry for future clinical studies that investigate polarization properties of arterial atherosclerosis.

First serial optical coherence tomography assessment at baseline, 12 and 24 months in STEMI patients treated with the second-generation Absorb bioresorbable vascular scaffold.

AIMS: The aim of the study was to assess the vascular healing response after Absorb bioresorbable vascular scaffold (BVS) implantation in patients with ST-segment elevation myocardial infarction (STEMI) utilising truly serial optical coherence tomography (OCT) examination at baseline, 12 and 24 months. METHODS AND RESULTS: This was a single-centre, prospective, longitudinal study with baseline, 12- and 24-month OCT evaluation of 18 STEMI patients treated with 22 Absorb BVS. The healing pattern was evaluated based upon lumen area, neointimal hyperplasia, strut coverage and apposition. The lumen area decreased at 12 months compared to baseline (8.52±1.69 mm² vs. 7.0±1.70 mm², p<0.01), but it did not change from that point onwards up to 24 months (7.0±1.70 mm² vs. 6.94±1.65 mm², p=0.92). At 12 months after the index procedure, the mean neointimal thickness was 217±69 µm and further neointimal hyperplasia was observed between 12 and 24 months though less pronounced (Δ62±44 µm, p<0.0001). Full circumferential coverage of the vessel wall by neointima was observed in 92% of frames at 24 months. The low number of malapposed struts at the index procedure (<5%) further decreased over the observation period and was found in only one patient at 12 and 24 months. The ratio of uncovered struts was low at both 12 and 24 months. CONCLUSIONS: This serial OCT analysis of the second-generation everolimus-eluting BVS in a STEMI population confirmed a favourable healing pattern as expressed by moderate neointimal growth, preserved lumen area and no late acquired malapposition.

Serial Assessment of Strut Coverage of Biodegradable Polymer Drug-Eluting Stent at 1, 2, and 3 Months After Stent Implantation by Optical Frequency Domain Imaging: The DISCOVERY 1TO3 Study (Evaluation With OFDI of Strut Coverage of Terumo New Drug Eluting Stent With Biodegradable Polymer at 1, 2, and 3 Months).

BACKGROUND: To assess the vessel-healing pattern of Ultimaster drug-eluting stent using optical frequency domain imaging. Our hypothesis is that biodegradable polymer-based drug-eluting technology allows complete very early strut coverage. METHODS AND RESULTS: The DISCOVERY 1TO3 study (Evaluation With OFDI of Strut Coverage of Terumo New Drug Eluting Stent With Biodegradable Polymer at 1, 2, and 3 Months) is a prospective, single-arm, multicenter study. A total of 60 patients with multivessel disease requiring staged procedure at 1 month were treated with Ultimaster. Optical frequency domain imaging was acquired at baseline, 1, 2, and 3 months. The primary end point is optical frequency domain imaging-assessed strut coverage at 3 months. Mean age of patients was 67.2±9.9 years, and 73.3% were male, and 36.7% presented with acute coronary syndrome. A total of 132 lesions were treated, with average 1.4 lesions per patient treated at baseline and 1.1 lesions treated at 1 month. Strut coverage at 3 months of single implanted stents (n=71, primary end point) was 95.2±5.2% and of combined single and overlapped stents was 95.4±4.9%. Strut coverage of combined single and overlapped stents at 1 (n=49) and 2 months (n=38) was 85.1±12.7% and 87.9±10.8%, respectively. The median neointimal hyperplasia thickness was 0.04, 0.05, and 0.06 mm, whereas mean neointimal hyperplasia obstruction was 4.5±2.4%, 5.2±3.4%, and 6.6±3.3% at 1, 2, and 3 months, respectively. CONCLUSIONS: Nearly complete strut coverage was observed in this complex population very early after implantation of Ultimaster drug-eluting stent. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01844843.

Navvus FFR to reduce CONTRAst, Cost and radiaTion (CONTRACT); insights from a single-centre clinical and economical evaluation with the RXi Rapid-Exchange FFR device.

OBJECTIVES: To assess whether the RXi Navvus system compared to the use of standard Fractional Flow Reserve (FFR) wires reduces total contrast volume, radiation and overall study cost in a real world patient population referred for coronary angiography or percutaneous coronary intervention. BACKGROUND: FFR is the mainstay of functional hemodynamic assessment of coronary artery lesions. The RXi Navvus system (ACIST Medical Systems, Eden Prairie, MN) is a monorail microcatheter with FFR-measurement capability through optical pressure sensor technology. METHODS: This is an investigator-initiated, prospective, single-center, observational cohort study. A total of 238 patients were enrolled, 97 patients with Navvus and 141 with conventional pressure-wire based FFR (PW-FFR). Final analyses were performed on the cohort in which only 1 device was used (82 Navvus procedures vs. 136 PW-FFR procedures). RESULTS: No significant differences were found in the total amount of contrast used (150±77 vs 147±79ml; p=0.81), radiation use (6200±4601 vs. 5076±4655 centiG∗cm2; p=0.09) or costs (€1994,- vs. €1930,-; p=0.32) in the Navvus vs. PW-FFR groups respectively. CONCLUSIONS: No significant differences were found in the amount of contrast used, total procedural costs or radiation when the Navvus system was used as compared to conventional FFR wires. CONDENSED ABSTRACT: CONTRACT is an investigator-initiated, prospective, single-center, observational cohort study that evaluated whether the RXi Navvus system compared to the use of standard Fractional Flow Reserve (FFR) wires reduces total contrast volume, radiation and overall study cost in a real world patient population referred for coronary angiography or percutaneous coronary intervention. Use of the RXi Navvus system was associated with comparable procedural costs, amount of radiation and contrast used as compared to PW-FFR systems.

Differential thrombotic prolapse burden in either bioresorbable vascular scaffolds or metallic stents implanted during acute myocardial infarction: The snowshoe effect: Insights from the maximal footprint analysis.

BACKGROUND: The hypothesized increased thrombus entrapment during bioresorbable vascular scaffold implantation in acute myocardial infarction, the so-called "snowshoe effect" has never been demonstrated. METHODS: Patients enrolled in the BVS STEMI FIRST study matched with STEMI patients implanted with everolimus-eluting metal stents (EES) and undergoing optical coherence tomography (OCT) at the index procedure were compared. Quantitative coronary angiography analysis and optical coherence tomography data for evaluation of thrombotic prolapse were reported. Percentage maximal footprint (%MFP) analysis as an indicator of the snowshoe effect was performed. RESULTS: A total of 302 patients were analyzed (151 with BVS and 151 with EES). Of those patients 30 implanted with BVS and 17 implanted with EES were imaged at the index procedure with OCT. Baseline clinical characteristics, TIMI-flow and thrombus burden were similar between groups. Aspiration thrombectomy was similarly performed in the two groups (BVS 83.3% vs 94.1% EES, p=0.405). At the end of the procedure, final TIMI 3 flow was achieved in 93.3% and 82.4% of BVS and EES patients respectively (p=0.296). The %MFP was significantly higher in the BVS treated patients (36.59±5.65% vs 17.61±4.30, p<0.001). The results of the OCT analysis showed a mean prolapse area (0.61±0.26mm(2) vs 0.90±0.31mm(2), p=0.001) and a percentage prolapse area (7.11±2.98mm(2) vs 9.98±2.90mm(2), p=0.002) significantly higher in the EES group. CONCLUSIONS: Scaffold structural characteristics such as strut width may play a role in terms of thrombus dislodgment patterns and acute prolapsing material.

Multimodality Intra-Arterial Imaging Assessment of the Vascular Trauma Induced by Balloon-Based and Nonballoon-Based Renal Denervation Systems.

BACKGROUND: Renal denervation is a new treatment considered for several possible indications. As new systems are introduced, the incidence of acute renal artery wall injury with relation to the denervation method is unknown. We investigated the acute repercussion of renal denervation on the renal arteries of patients treated with balloon-based and nonballoon-based denervation systems by quantitative angiography, intravascular ultrasound, and optical coherence tomography (OCT). METHODS AND RESULTS: Twenty-five patients (50 renal arteries) underwent bilateral renal denervation with 5 different systems, 3 of which balloon-based (Paradise [n=5], Oneshot [n=6], and Vessix V2 [n=5)]) and 2 nonballoon-based (Symplicity [n=6] and EnligHTN [n=3]). Analysis included quantitative angiography and morphometric intravascular ultrasound measurements pre and post procedure and assessment of vascular trauma (dissection, edema, or thrombus) by OCT after denervation. A significant reduction in lumen size by quantitative angiography and intravascular ultrasound was observed in nonballoon denervation but not in balloon denervation. By postdenervation OCT, dissection was seen in 14 arteries (32.6%). The percentage of frames with dissection was higher in balloon-based denervation catheters. Thrombus and edema were detected in 35 (81.4%) and 32 (74.4%) arteries, respectively. In arteries treated with balloon-based denervation that had dissection by OCT, the balloon/artery ratio was higher (1.24 [1.17-1.32] versus 1.10 [1.04-1.18]; P<0.01). CONCLUSIONS: A varying extent of vascular injury was observed after renal denervation in all systems; however, different patterns were identified in balloon-based and in nonballoon-based denervation systems. In balloon denervation, the presence of dissections by OCT was associated with a higher balloon/artery ratio.

A novel method to assess coronary artery bifurcations by OCT: cut-plane analysis for side-branch ostial assessment from a main-vessel pullback.

AIMS: In coronary bifurcations assessment, evaluation of side-branch (SB) ostia by an optical coherence tomography (OCT) pullback performed in the main branch (MB) could speed up lesion evaluation and minimize contrast volume. Dedicated software that reconstructs the cross-sections perpendicular to the SB centreline could improve this assessment. We aimed to validate a new method for assessing the SB ostium from an OCT pullback performed in the MB. METHODS AND RESULTS: Thirty-one sets of frequency-domain OCT pullbacks from 28 patients, both from the MB and the SB of a coronary artery bifurcation were analysed. Measurements of the SB ostium from the SB pullback were used as a reference. Measurements of the SB ostium from the MB pullback were then performed in a laboratory setting by (i) conventional analysis and (ii) cut-plane analysis, and the measurement error for each analysis was estimated. Correlations of SB ostium measurements acquired from the MB pullback in comparison with reference measurements acquired from the SB pullback were higher with cut-plane analysis compared with conventional analysis, albeit not reaching statistical significance (area: rcut-plane = 0.927 vs. rconventional = 0.870, P = 0.256; mean diameter: rcut-plane = 0.918 vs. rconventional = 0.788, P = 0.056; minimum diameter: rcut-plane = 0.841 vs. rconventional = 0.812, P = 0.734; maximum diameter: rcut-plane = 0.770 vs. rconventional = 0.635, P = 0.316). Cut-plane analysis was associated with lower absolute error than conventional analysis (area: 0.56 ± 0.45, vs. 1.50 ± 1.31 mm(2), P < 0.001; mean diameter: 0.18 ± 0.14 vs. 0.44 ± 0.30 mm, P < 0.001). CONCLUSION: Measurements of SB ostium performed in a laboratory setting by cut-plane analysis of an OCT pullback of the main branch have high correlation with reference measurements performed in a SB OCT pullback and lower error compared with conventional analysis.

OCT assessment of the long-term vascular healing response 5 years after everolimus-eluting bioresorbable vascular scaffold.

BACKGROUND: Although recent observations suggest a favorable initial healing process of the everolimus-eluting bioresorbable vascular scaffold (BVS), little is known regarding long-term healing response. OBJECTIVES: This study assessed the in vivo vascular healing response using optical coherence tomography (OCT) 5 years after elective first-in-man BVS implantation. METHODS: Of the 14 living patients enrolled in the Thoraxcenter Rotterdam cohort of the ABSORB A study, 8 patients underwent invasive follow-up, including OCT, 5 years after implantation. Advanced OCT image analysis included luminal morphometry, assessment of the adluminal signal-rich layer separating the lumen from other plaque components, visual and quantitative tissue characterization, and assessment of side-branch ostia "jailed" at baseline. RESULTS: In all patients, BVS struts were integrated in the vessel and were not discernible. Both minimum and mean luminal area increased from 2 to 5 years, whereas lumen eccentricity decreased over time. In most patients, plaques were covered by a signal-rich, low-attenuating layer. Minimum cap thickness over necrotic core was 155 ± 90 µm. One patient showed plaque progression and discontinuity of this layer. Side-branch ostia were preserved with tissue bridge thinning that had developed in the place of side-branch struts, creating a neo-carina. CONCLUSIONS: At long-term BVS follow-up, we observed a favorable tissue response, with late luminal enlargement, side-branch patency, and development of a signal-rich, low-attenuating tissue layer that covered thrombogenic plaque components. The small size of the study and the observation of a different tissue response in 1 patient warrant judicious interpretation of our results and confirmation in larger studies.

Quantification of scientific output in cardiovascular medicine: a perspective based on global data.

AIMS: We sought to explore whether global and regional scientific output in cardiovascular medicine is associated with economic variables and follows the same trend as medicine and as science overall. METHODS AND RESULTS: We registered the number of documents, number of citations, citations per document and the h-index for the first 50 countries according to the h-index (a measure to evaluate both the productivity and impact of the publications) in cardiovascular medicine. Economic variables (gross domestic product [GDP] per capita, % expenditure of the GDP in research and development [R&D] and health) were obtained from the World Bank, the UNESCO, and the World Health Organization. In total, the scientific output in cardiology showed the same position as in medicine and science overall (mean difference vs. medicine -0.9±5.3º, p=0.25 vs. science -0.7±5.3º, p=0.39). We found significant correlations between the h-index and the % GDP expenditure in R&D (r=0.67, p<0.001), and the % GDP expenditure in health (r=0.71, p<0.0001). Overall, there was a 21.4% (interquartile range 3.7; 55.0) increase in the % GDP expenditure in R&D between 1996 and 2007. Emerging economies showed the larger growth in % GDP expenditure in health and R&D. CONCLUSIONS: The global situation of scientific output in cardiovascular medicine is highly polarised and closely related to economic indicators. Emergent economies, with higher rates of GDP growth and increasingly larger expenditures for R&D and healthcare, are expected to show a visible escalation in the scientific global picture in the near future.

Tissue coverage and neointimal hyperplasia in overlap versus nonoverlap segments of drug-eluting stents 9 to 13 months after implantation: in vivo assessment with optical coherence tomography.

BACKGROUND: Histologic experimental studies have reported incomplete neointimal healing in overlapping with respect to nonoverlapping segments in drug-eluting stents (DESs), but these observations have not been confirmed in human coronary arteries hitherto. On the contrary, angiographic and optical coherence tomography studies suggest that DES overlap elicits rather an exaggerated than an incomplete neointimal reaction. METHODS: Optical coherence tomography studies from 2 randomized trials including sirolimus-eluting, biolimus-eluting, everolimus-eluting, and zotarolimus-eluting stents were analyzed at 9- to 13-month follow-up. Coverage in overlapping segments was compared versus the corresponding nonoverlapping segments of the same stents, using statistical pooled analysis. RESULTS: Forty-two overlaps were found in 31 patients: 11 in sirolimus-eluting stents, 3 in biolimus-eluting stents, 17 in everolimus-eluting stents, and 11 in zotarolimus-eluting stents. The risk ratio of incomplete coverage was 2.35 (95% CI 1.86-2.98) in overlapping versus nonoverlapping segments. Thickness of coverage in overlaps was only 85% (95% CI 81%-90%) of the thickness in nonoverlaps. Significant heterogeneity of the effect was observed, especially pronounced in the comparison of thickness of coverage (I(2) = 90.31). CONCLUSIONS: The effect of overlapping DES on neointimal inhibition is markedly heterogeneous: on average, DES overlap is associated with more incomplete and thinner coverage, but in some cases, the overlap elicits an exaggerated neointimal reaction, thicker than in the corresponding nonoverlapping segments. These results might help to understand why overlapping DES is associated with worse clinical outcomes, both in terms of thrombotic phenomena and in terms of restenosis and revascularization.

Health-related quality of life in the elderly three years after percutaneous coronary intervention.

AIMS: Long-term health-related quality of life (HRQOL) in the elderly after percutaneous coronary intervention (PCI) is unknown. We 1) compared HRQOL of elderly (≥70 years) with younger patients (<70 years) at 6, 12, 36 months post-PCI, and 2) examined whether predictors of impaired HRQOL 36 months post-PCI differed between older and younger patients. METHODS AND RESULTS: A prospective cohort of 651 PCI patients (26.3% ≥70 years) completed the SF-36 at 6, 12 and 36 months post-PCI. Older patients experienced a poorer physical HRQOL at all time points and worse mental HRQOL with respect to vitality and role emotional functioning (all p-values<0.05). By 36 months, the HRQOL for the older patients worsened in five of the eight subdomains (all p-values<0.05). Younger patients did not experience enduring changes in HRQOL, with the exception of role physical functioning. Predictors of impaired HRQOL were generally different for the elderly (diabetes, previous PCI) compared to younger cohorts (smoking, previous bypass surgery, ACE inhibitors), although poor six-month HRQOL, anxiety and depression were common predictors for both groups. CONCLUSIONS: Elderly PCI patients experience a deteriorating and poorer HRQOL than younger patients across three years. Contrary to younger patients, three-year HRQOL of elderly patients is irrespective of adverse events during outcomes.

Online 3-dimensional rendering of optical coherence tomography images for the assessment of bifurcation intervention.

Three-dimensional optical coherence tomography rendering has been suggested as a method providing additive information for the assessment of the result of percutaneous coronary intervention. However, rendering of such models is very time-consuming and cannot be performed online during the intervention. We present a case in which a new method for 3-dimensional rendering of optical coherence tomography images helped visualize the stent-vessel wall interaction, providing useful information that discouraged further intervention.

Vascular response of the segments adjacent to the proximal and distal edges of the ABSORB everolimus-eluting bioresorbable vascular scaffold: 6-month and 1-year follow-up assessment: a virtual histology intravascular ultrasound study from the first-in-man ABSORB cohort B trial.

OBJECTIVES: This study sought to investigate in vivo the vascular response at the proximal and distal edges of the second-generation ABSORB everolimus-eluting bioresorbable vascular scaffold (BVS). BACKGROUND: The edge vascular response after implantation of the BVS has not been previously investigated. METHODS: The ABSORB Cohort B trial enrolled 101 patients and was divided into B(1) (n = 45) and B(2) (n = 56) subgroups. The adjacent (5-mm) proximal and distal vessel segments to the implanted ABSORB BVS were investigated at either 6 months (B(1)) or 1 year (B(2)) with virtual histology intravascular ultrasound (VH-IVUS) imaging. RESULTS: At the 5-mm proximal edge, the only significant change was modest constrictive remodeling at 6 months (Δ vessel cross-sectional area: -1.80% [-3.18; 1.30], p < 0.05), with a tendency to regress at 1 year (Δ vessel cross-sectional area: -1.53% [-7.74; 2.48], p = 0.06). The relative change of the fibrotic and fibrofatty (FF) tissue areas at this segment were not statistically significant at either time point. At the 5-mm distal edge, a significant increase in the FF tissue of 43.32% [-19.90; 244.28], (p < 0.05) 1-year post-implantation was evident. The changes in dense calcium need to be interpreted with caution since the polymeric struts are detected as "pseudo" dense calcium structures with the VH-IVUS imaging modality. CONCLUSIONS: The vascular response up to 1 year after implantation of the ABSORB BVS demonstrated some degree of proximal edge constrictive remodeling and distal edge increase in FF tissue resulting in nonsignificant plaque progression with adaptive expansive remodeling. This morphological and tissue composition behavior appears to not significantly differ from the behavior of metallic drug-eluting stents at the same observational time points.

Vascular tissue reaction to acute malapposition in human coronary arteries: sequential assessment with optical coherence tomography.

BACKGROUND: The vascular tissue reaction to acute incomplete stent apposition (ISA) is not well known. The aim of this study was to characterize the vascular response to acute ISA in vivo and to look for predictors of incomplete healing. METHODS AND RESULTS: Optical coherence tomography studies of 66 stents of different designs, implanted in 43 patients enrolled in 3 randomized trials, were analyzed sequentially after implantation and at 6 to 13 months. Seventy-eight segments with acute ISA were identified in 36 of the patients and matched with the follow-up study by use of fiduciary landmarks. The morphological pattern of healing in the ISA segments was categorized as homogeneous, layered, crenellated, bridged, partially bridged, or bare, depending on the persistence of ISA and on the coverage. After 6 months, acute ISA volume decreased significantly, and 71.5% of the ISA segments were completely integrated into the vessel wall. Segments with acute ISA had higher risk of delayed coverage than well-apposed segments (relative risk 2.37, 95% confidence interval 2.01-2.78). Acute ISA size (estimated as ISA volume or maximum ISA distance per strut) was an independent predictor of ISA persistence and of delayed healing at follow-up. CONCLUSIONS: Neointimal healing tends to reduce ISA, with the malapposed stent struts often integrated completely into the vessel wall, resulting in characteristic morphological patterns. Coverage of ISA segments is delayed with respect to well-apposed segments. The larger the acute ISA, the greater the likelihood of persistent malapposition at follow-up and delayed healing.

Long-term tissue coverage of a biodegradable polylactide polymer-coated biolimus-eluting stent: comparative sequential assessment with optical coherence tomography until complete resorption of the polymer.

BACKGROUND: Biolimus-eluting stents (BESs) with a biodegradable polymer in abluminal coating achieve more complete coverage at 9 months compared with sirolimus-eluting stents (SESs) with a durable polymer, as assessed by optical coherence tomography (OCT). Whether this advantage persists or augments after complete resorption of the polymer (>12 months) is unknown. METHODS: The LEADERS trial compared the performance of BES with that of SES. Patients were randomly allocated to a sequential angiographic follow-up, including OCT in selected sites, at 9 and 24 months. Struts coverage was compared using Bayesian hierarchical models as the primary outcome for the OCT substudy. RESULTS: Fifty-six patients (26 BES, 30 SES) were enrolled in the OCT substudy. Twenty-one patients (10 BES, 11 SES) agreed to perform a second OCT follow-up at 24 months. Eleven lesions and 12 stents were analyzed sequentially in the BES group (2,455 struts at 9 months, 2,131 struts at 24 months) and 11 lesions and 18 stents in the SES group (3,421 struts at 9 months, 4,170 struts at 24 months). The previously reported advantage of BES over SES in terms of better strut coverage at 9 months was followed by improvement in coverage of the SES, resulting in identical coverage in both BES and SES at 24 months: 1.5% versus 1.8% uncovered struts, difference -0.2%, 95% credibility interval, -3.2% to 2.6%, P = .84. CONCLUSIONS: More complete strut coverage of BES as compared with SES at 9 months was followed by improvement of coverage in SES between 9 and 24 months and a similar long-term coverage in both stent types at 24 months.