Sex-specific Inequalities in the Treatment of Severely Calcified Coronary Lesions: A Sub-analysis of the PREPARE-CALC Trial.

Background: Coronary vessels in women may have anatomical and histological particularities. The aim of this study was to investigate sex-specific characteristics and outcomes of patients with calcified coronary arteries in the Prepare-CALC (Comparison of Strategies to Prepare Severely Calcified Coronary Lesions) trial. Methods: The Prepare-CALC trial randomised patients with severe coronary calcification to coronary lesion preparation either using modified balloons (MB; cutting or scoring) or rotational atherectomy (RA). Results: Of 200 randomised patients, 24% were women. Strategy success in general was similar between women (93.8%) and men (88.2%; p=0.27). For men, strategy success was significantly more common with an RA-based strategy than an MB-based strategy (98.7% in the RA group versus 77.3% in the MB group, p<0.001), whereas for women there was no evidence of a significant difference in strategy success between RA and MB (95.7% in the RA group versus 92% in the MB group, p>0.99, p for interaction between sex and treatment strategy=0.03). Overall, significant complications such as death, MI, stent thrombosis, bypass operation and perforations were rare and did not differ significantly by gender or treatment strategy. Plaque rupture and disrupted calcified nodules were more common in women. Conclusion: In a well-defined patient population with severely calcified coronary arteries, lesion preparation with an RA-strategy was superior to an MB-strategy in men. For women, both RA and MB strategies appear to have a similar success rate, although definitive conclusions are limited due to the small number of women in the trial.

Rotational atherectomy of calcified coronary lesions: current practice and insights from two randomized trials.

With growing experience, technical improvements and use of newer generation drug-eluting stents (DES), recent data showed satisfactory acute and long-term results after rotational atherectomy (RA) in calcified coronary lesions. The randomized ROTAXUS and PREPARE-CALC trials compared RA to balloon-based strategies in two different time periods in the DES era. In this manuscript, we assessed the technical evolution in RA practice from a pooled analysis of the RA groups of both trials and established a link to further recent literature. Furthermore, we sought to summarize and analyze the available experience with RA in different patient and lesion subsets, and propose recommendations to improve RA practice. We also illustrated the combination of RA with other methods of lesion preparation. Finally, based on the available evidence, we propose a simple and practical approach to treat severely calcified lesions.

Rotational Atherectomy or Balloon-Based Techniques to Prepare Severely Calcified Coronary Lesions.

BACKGROUND: The comparative efficacy of percutaneous techniques for the preparation of calcified lesions before stenting remains poorly studied. OBJECTIVES: This study sought to compare the performance of up-front rotational atherectomy (RA) or balloon-based techniques before drug-eluting stent implantation in severely calcified coronary lesions as assessed by angiography and optical coherence tomography (OCT). METHODS: Patient-level data from the PREPARE-CALC (Comparison of Strategies to Prepare Severely Calcified Coronary Lesions) and ISAR-CALC (Comparison of Strategies to Prepare Severely Calcified Coronary Lesions) randomized trials were pooled. The primary endpoint was stent expansion as assessed by OCT imaging. The secondary endpoints included stent eccentricity, stent asymmetry, angiographic acute lumen gain, strategy success and in-hospital occurrence of cardiac death, target vessel myocardial infarction, and repeat revascularization. RESULTS: Among 274 patients originally randomized, 200 participants with available OCT data after lesion preparation with RA (n = 63), a modified balloon (MB, n = 103), or a super high-pressure balloon (n = 34) before stenting were analyzed. The use of RA versus MB or a super high-pressure balloon led to comparable stent expansion (73.2% ± 11.6% vs 70.8% ± 13.6% vs 71.8% ± 12.2%, P = 0.49) and stent asymmetry (P = 0.83). Compared with RA or MB, a super high-pressure balloon was associated with less stent eccentricity (P = 0.03) with a numerically higher acute lumen gain, albeit not significantly different (P = 0.08). Strategy success was more frequent with RA versus MB (P = 0.002) and numerically more frequent with RA versus a super high-pressure balloon (P = 0.06). Clinical outcomes did not differ between groups. CONCLUSIONS: In patients with severely calcified lesions undergoing drug-eluting stent implantation, lesion preparation with RA, MB, or a super high-pressure balloon was associated with comparable stent expansion. A super high-pressure balloon is associated with less stent eccentricity, whereas strategy success is more frequent with RA.

Angiographic predictors of unplanned rotational atherectomy in complex calcified coronary artery disease: a pooled analysis from the randomised ROTAXUS and PREPARE-CALC trials.

BACKGROUND: Calcified coronary lesions present therapeutic challenges for the interventional cardiologist, often requiring rotational atherectomy (RA). AIMS: This study aimed to develop an angiographic scoring tool to predict the need for a priori RA. METHODS: A pooled analysis of the randomised ROTAXUS and PREPARE-CALC studies was carried out, (N=220 patients, N=313 lesions), by virtue of the fact that both studies made provision for crossover to RA (from balloon dilatation or modified balloon dilatation, respectively). Logistical regression techniques were employed to assess for the presence of patient- or lesion-specific factors leading to a necessity for RA. External validation was performed though retrospective calculation of the score for 192 patients who underwent bail-out RA in a single centre. RESULTS: Lesion length (odds ratio [OR] 1.02, 95% confidence interval [CI]: 1.00-1.04 per mm, p=0.04), bifurcation lesion (OR 2.60, 95% CI: 1.27-5.30, p=0.009), vessel tortuosity >45° (OR 3.49, 95% CI: 1.73-7.03, p<0.001) and severe vessel calcification (OR 11.60, 95% CI: 3.40-39.64, p<0.001) were predictive of the need for RA in multivariate analysis. Based on the regression coefficients, a scoring system was devised. The greater the score, the more likely a lesion required RA. The scoring system performed well in the external validation cohort, with 78% of patients crossing over having a score of greater than the proposed cut-off of 3. CONCLUSIONS: We provide an angiographic scoring tool to support the expeditious use of time and resources, allowing assessment of the likelihood of success of a balloon-based strategy, or the necessity for RA.

Feasibility and safety of minimal-contrast IVUS-guided rotational atherectomy for complex calcified coronary artery disease.

OBJECTIVES: To assess the feasibility and safety of minimal-contrast percutaneous coronary intervention (PCI) using rotational atherectomy (RA) in patients with severe coronary calcification at high-risk of contrast-associated acute kidney injury (AKI). METHODS: Twenty-six patients with advanced chronic kidney disease undergoing PCI with RA at three high-volume centres were included. Baseline intravascular ultrasound (IVUS) was performed to assess lesion morphology, and to guide burr-, balloon-, and stent-selection. Final result was assessed by IVUS and angiographically. Feasibility and safety were determined by procedural and in-hospital complications, and efficacy was assessed by freedom from contrast-associated AKI after PCI. Procedural and in-hospital outcome was compared to a propensity-matched population of standard RA PCI. RESULTS: Mean glomerular filtration rate was 32 ± 17 ml/min/1.73 m2. In seven cases PCI was performed in the setting of acute coronary syndrome. The left main coronary artery was treated in 27.8% and a two-stent bifurcation technique in 44.4%. RA was more often performed electively compared to the standard RA cohort (92.3 vs. 50%; p = 0.0016). Angiographic success was achieved in 100% and documented with a median contrast amount of 12.5 ml [Range 4-43]. No in-hospital death or myocardial infarction was reported. Contrast-associated AKI occurred in one patient versus five patients in standard RA group (p = 0.19). Shorter fluoroscopy time and lower radiation dose were achieved as compared to standard RA. CONCLUSION: A minimal-contrast RA approach with IVUS-guidance for treatment of complex calcified coronary lesions is feasible and safe with high success rate.

Optical Coherence Tomography Assessment in Patients Treated With Rotational Atherectomy Versus Modified Balloons: PREPARE-CALC OCT.

[Figure: see text].

Impact of Calcified Lesion Complexity on the Success of Percutaneous Coronary Intervention With Upfront High-Speed Rotational Atherectomy or Modified Balloons - A Subgroup-Analysis From the Randomized PREPARE-CALC Trial.

BACKGROUND/PURPOSE: In the randomized PREPARE-CALC trial, lesion preparation of calcified lesions with upfront rotational atherectomy (RA) prior to drug-eluting stent (DES) implantation resulted in higher acute success as compared to a provisional modified balloon (MB) strategy. We aimed to investigate the impact of calcified lesion complexity on the treatment effect with either MB or RA. METHODS/MATERIALS: Two hundred patients were randomized to lesion preparation with either MB or RA. The study population was stratified according to lesion complexity into at least one type-C lesion or into exclusively non-type-C lesions. Endpoints were strategy success, need for bail-out RA, acute lumen gain, and late lumen loss (LLL) at 9 months. RESULTS: In total, 143 patients were graded as type-C (45% patients were allocated to MB), whereas 57 patients were graded as non-type-C (61% patients were allocated to MB). In patients with at least one type-C lesion, strategy success with RA was higher than with MB (97% vs 72%, p < 0.001), but superiority of RA was not observed in patients with non-type-C lesions (100% vs 97%, p = 1.00; pinteraction = 0.001). The need for bail-out RA was higher in patients with type-C lesions (n = 15) as compared with non-type-C lesions (n = 1). Acute lumen gain, LLL, and target lesion revascularization at 9 months were not dependent on lesion complexity and upfront lesion preparation strategy. CONCLUSIONS: In patients with calcified non-type-C lesions, the treatment strategy with RA or MB before DES implantation results in comparable success rates, whereas in type-C lesions upfront RA appears to be the superior upfront strategy.

Super high-pressure balloon versus scoring balloon to prepare severely calcified coronary lesions: the ISAR-CALC randomised trial.

BACKGROUND: The comparative efficacy of balloon-based techniques to prepare severely calcified coronary lesions before stenting remains poorly studied. AIMS: We sought to compare stent expansion following preparation of severely calcified coronary lesions with either a super high-pressure balloon or a scoring balloon. METHODS: In this randomised, open-label trial, patients with severely calcified coronary lesions were enrolled at five centres in Germany and Switzerland. After unsuccessful lesion preparation with a standard non-compliant balloon (<30% reduction of baseline diameter stenosis), participants were randomised to predilation with either a super high-pressure balloon or a scoring balloon before drug-eluting stent (DES) implantation. The primary endpoint of the study was stent expansion index as assessed by optical coherence tomography (OCT). The key secondary endpoints included angiographic, strategy and procedural success. RESULTS: OCT data after DES implantation were available for 70 out of 74 patients (94.6%) enrolled. Lesion preparation with a super high-pressure balloon versus a scoring balloon led to a comparable stent expansion index (0.72±0.12 vs 0.68±0.13; p=0.22). Compared with the scoring balloon, the super high-pressure balloon increased the minimum lumen diameter (2.83±0.34 mm vs 2.65±0.36 mm; p=0.03) and reduced the diameter stenosis (11.6±4.8% vs 14.4±5.6%; p=0.02) without difference in terms of angiographic success (100% vs 97.3%; p>0.99). Strategy success (91.9% vs 83.8%; p=0.48) and procedural success (100% vs 89.2%; p=0.12) were numerically more frequent with the super high-pressure balloon versus the scoring balloon. CONCLUSIONS: In patients with severely calcified coronary artery lesions, preparation with a super high-pressure balloon versus a scoring balloon was associated with comparable stent expansion on intravascular imaging and a trend towards improved angiographic performance. Visual summary. A ComparIson of Strategies to PrepAre SeveRely CALCified Coronary Lesions: the ISAR-CALC randomised trial.

Bioprosthetic Valve Performance After Transcatheter Aortic Valve Replacement With Self-Expanding Versus Balloon-Expandable Valves in Large Versus Small Aortic Valve Annuli: Insights From the CHOICE Trial and the CHOICE-Extend Registry.

OBJECTIVES: The aim of this study was to compare self-expanding and balloon-expandable transcatheter heart valves (THVs) in large versus small aortic valve annuli. BACKGROUND: The degree of THV oversizing varies according to annular size, and this can modify the hemodynamic performance of self-expanding and balloon-expandable THVs. METHODS: Patients undergoing transcatheter aortic valve replacement in the randomized CHOICE (Comparison of Transcatheter Heart Valves in High Risk Patients With Severe Aortic Stenosis: Medtronic CoreValve vs Edwards SAPIEN XT) trial (CoreValve [CV], n = 120; SAPIEN XT [SXT], n = 121) and the nonrandomized CHOICE-Extend registry (Evolut R [ER], n = 100; SAPIEN 3 [S3], n = 334) were compared for THV performance by echocardiography (in all patients) and by cardiac magnetic resonance imaging (MRI) regurgitant fraction (RF) (in a subgroup of patients). Patients were stratified according to aortic valve annular mean diameter into those with large (>23 mm) or small (≤23 mm) annuli. RESULTS: THV percentage oversizing was 19.1 ± 6.4% with the CV, 11.4 ± 7.0% with the SXT, 18.8 ± 4.8% with the ER, and 3.7 ± 5.5% with the S3. Transvalvular mean pressure gradient was lower with the CV and ER than with the SXT and S3 in both the large and small annulus groups. In the randomized CHOICE trial, moderate to severe prosthetic valve regurgitation (PVR) was more with the CV than the SXT in large annuli (15.1% vs. 0.0%; p = 0.002; MRI RF: 10.5 ± 10.2% vs. 4.4 ± 4.5%; p = 0.036) but not in small annuli (0.0% vs. 5.7%; p = 0.50; MRI RF: 4.0 ± 4.1% vs. 4.0 ± 3.4%; p = 0.98). In the CHOICE-Extend registry, moderate to severe PVR occurred in 2 patients, and any PVR was not significantly different between the ER and the S3 in large (41.7% vs. 32.5%; p = 0.24) or small (47.1% vs. 43.8%; p = 0.84) annuli. MRI RF was not different in large annuli (5.0 ± 3.8% vs. 5.0 ± 6.1%; p = 0.99) but was significantly lower with the ER than the S3 in small annuli (2.9 ± 2.3% vs. 4.8 ± 3.7%; p = 0.023). On multivariate analysis, transcatheter aortic valve replacement with the ER in small annuli was associated with a lower rate of prosthesis-patient mismatch than with the S3, with no increased risk for PVR. CONCLUSIONS: Older-generation balloon-expandable THVs were associated with less PVR than self-expanding THVs in patients with large but not small annuli. The next-generation self-expanding THV has improved sealing in patients with large annuli and may have potential advantages in patients with small annuli.

High-Speed Rotational Atherectomy Versus Modified Balloons Prior to Drug-Eluting Stent Implantation in Severely Calcified Coronary Lesions.

BACKGROUND: Balloon dilatation or debulking seems to be essential to allow successful stent implantation in calcified coronary lesions. Compared with standard balloon predilatation, debulking using high-speed rotational atherectomy (RA) is associated with higher initial procedural success albeit with higher in-stent late lumen loss at intermediate-term follow-up. Whether modified (scoring or cutting) balloons (MB) could achieve similar procedural success compared with RA is not known. In addition, whether new-generation drug-eluting stents could counterbalance the excessive neointimal proliferation triggered by RA remains to be determined. METHODS AND RESULTS: We randomly assigned patients with documented myocardial ischemia and severely calcified native coronary lesions undergoing percutaneous coronary intervention to a strategy of lesion preparation using MB or RA followed by drug-eluting stent implantation. Stenting was performed using a third-generation sirolimus-eluting stent with a bioabsorbable polymer. The trial had 2 primary end points: strategy success (defined as successful stent delivery and expansion with attainment of <20% in-stent residual stenosis in the presence of TIMI [Thrombolysis in Myocardial Infarction] 3 flow without crossover or stent failure; powered for superiority) and in-stent late lumen loss at 9 months (powered for noninferiority). Two hundred patients were enrolled at 2 centers in Germany (n=100 in each treatment group). The mean age of the study population was 74.9±7.0 years; 76% were men, and 33.5% had diabetes mellitus. Strategy success was significantly more common in the RA group (81% versus 98%; relative risk of failure with an MB- versus RA-based strategy, 9.5; 95% CI, 2.3-39.7; P=0.0001), but mean fluoroscopy time was longer (19.6±13.4 versus 23.9±12.2 minutes; P=0.03). At 9 months, mean in-stent late lumen loss was 0.16±0.39 mm in the MB group and 0.22±0.40 mm in the RA group ( P=0.21, P=0.02 for noninferiority). Target lesion revascularization (7% versus 2%; P=0.17), definite or probable stent thrombosis (0% versus 0%; P=1.00), and target vessel failure (8% versus 6%; P=0.78) were low and not significantly different between the MB and RA groups. CONCLUSIONS: Lesion preparation with upfront RA before drug-eluting stent implantation is feasible in nearly all patients with severely calcified coronary lesions, is more commonly successful as a primary strategy compared with MB, and is not associated with excessive late lumen loss. A strategy of provisional MB remains feasible, safe, and effective as long as bailout RA is readily available and may offer the advantages of compatibility with smaller sized catheters and less irradiation. Both strategies are associated with excellent clinical outcome at 9 months. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02502851.

The fate of incomplete scaffold apposition of everolimus-eluting bioresorble scaffolds: A serial optical coherence tomography analysis.

BACKGROUND: Incomplete stent apposition (ISA) can be divided into acute and late forms. Late ISA may be due to persistent ISA or late-acquired ISA (LAISA). This study evaluated the natural course of ISA after bioresorbable vascular scaffold (BRS) implantation using optical coherence tomography (OCT). METHODS: Thirty-two patients (45 BRS) were assessed immediately after BRS implantation and 1 year thereafter using OCT. Acute ISA identified after BRS implantation but absent at follow-up was defined as resolved; otherwise, it was considered persistent. LAISA was defined as newly developed ISA that was identified at follow-up despite complete apposition immediately after BRS implantation. Intra-BRS fibrin-like material (IBF) was identified as an irregular intraluminal mass. ISA percentage was expressed as follows: (number of ISA/total number of BRS struts)×100. RESULTS: Among 45 BRS and 15,894 analyzed BRS struts, 34 and 882 had acute ISA post-procedure, respectively. At follow-up, 92 of 15,364 analyzed struts exhibited late ISA (64 persistent ISA and 28 LAISA). In 15 of 28 struts with LAISA, LAISA occurred at the sites adjacent to post-interventional dissection. Uncovered struts were more frequently observed in late ISA compared to apposed struts (3.7±4.8 vs. 0.58±2.2%, p=0.09). IBF was significantly more common in BRS with late ISA (62.5 vs. 8.1%, p=0.02). Receiver-operating characteristic curve analysis identified a cut-off value of 280µm for acute ISA distance predicting persistent ISA. CONCLUSION: Resolution of acute ISA after BRS is common. The occurrence of LAISA may be infrequent and may be a nidus of stent thrombosis.

Clinical Bioprosthetic Heart Valve Thrombosis After Transcatheter Aortic Valve Replacement: Incidence, Characteristics, and Treatment Outcomes.

OBJECTIVES: The aim of this study was to determine the incidence, characteristics, and treatment outcomes of patients diagnosed with clinical transcatheter heart valve thrombosis. BACKGROUND: Limited data exists on clinical or manifest transcatheter heart valve thrombosis. Prior studies have focused on subclinical thrombosis. METHODS: A retrospective analysis was conducted of prospectively collected data from a single-center registry that included 642 consecutive patients who underwent transcatheter aortic valve replacement between 2007 and 2015 (305 patients had self-expanding valves; balloon-expandable, n = 281; mechanically expanding, n = 56). Long-term oral anticoagulation (OAC) was indicated in 261 patients, while 377 patients received dual-antiplatelet therapy post-procedure. All patients underwent scheduled clinical and echocardiographic follow-up. RESULTS: The overall incidence of clinical valve thrombosis was 2.8% (n = 18). No patient on OAC developed thrombosis. Of the detected thrombosis cases, 13 patients had balloon-expandable, 3 had self-expanding, and 2 had mechanically expanding valves. Thrombosis occurred significantly more often with balloon-expandable valves (odds ratio: 3.45; 95% confidence interval: 1.22 to 9.81; p = 0.01) and following valve-in-valve procedures (odds ratio: 5.93; 95% confidence interval: 2.01 to 17.51; p = 0.005). Median time to diagnosis of valve thrombosis was 181 days. The median N-terminal pro-brain natriuretic peptide level was 1,318 pg/ml (interquartile range: 606 to 1,676 pg/ml). The mean transvalvular gradient and valve area were 34 ± 14 mm Hg and 1.0 ± 0.46 cm2, respectively. Computed tomography showed hypoattenuating areas with reduced leaflet motion. Initiation of OAC resulted in significant reduction of transvalvular gradient and clinical improvement. No deaths were related to valve thrombosis. CONCLUSIONS: Clinical transcatheter heart valve thrombosis is more common than previously considered, characterized by imaging abnormalities and increased gradients and N-terminal pro-brain natriuretic peptide levels. It occurred more commonly after balloon-expandable transcatheter aortic valve replacement and valve-in-valve procedures. OAC appeared to be effective in the prevention and treatment of valve thrombosis. Randomized control trials are needed to define optimal antithrombotic therapy after transcatheter aortic valve replacement.

Comparison of Bailout and Planned Rotational Atherectomy for Heavily Calcified Coronary Lesions: A Single-Center Experience.

OBJECTIVES: The aim of this study was to compare outcomes of bailout and planned rotational atherectomy (RA) in the treatment of calcified coronary lesions. BACKGROUND: Current guidelines recommend RA as a bailout procedure for calcified or fibrotic lesions that cannot be adequately dilated before stenting. Nonetheless, planned RA is sometimes performed in certain challenging anatomies. METHODS: Data of patients treated with RA between 2002 and 2014 at a single-center registry were retrospectively analyzed. The bailout RA group included patients where RA was employed after failure of balloon dilatation or stent delivery. Planned RA included patients where RA was employed electively without previous device failure. RESULTS: The study comprised 204 patients (221 lesions) and 308 patients (338 lesions) treated with bailout or planned RA, respectively. Angiographic success was achieved in the majority of cases, but was lower in the bailout RA group (93.7% vs. 97.6%, P = 0.02). Coronary dissections occurred more frequently in the bailout RA group (8.6% vs. 4.4%, P = 0.04), mean contrast amount was higher (279 ± 135 mL vs. 202 ± 92 mL, P < 0.001), and fluoroscopy time and procedural duration were longer in that group (32 min [IQR 21-51] vs. 18 min [IQR 14-28], P < 0.001 and 111 ± 50 min vs. 76 ± 35 min, P < 0.001, respectively). In-hospital death and myocardial infarction were not significantly different between the groups (2.9% vs. 1.3%, P = 0.21 and 6.9% vs. 4.2%, P = 0.19). In-hospital major adverse cardiac events (MACE) were higher in the bailout RA group (10.3% vs. 5.5%, P = 0.04). The 2-year estimated rates of MACE (25.2% vs. 28.7%, log rank P = 0.52) and its components death, myocardial infarction, and target vessel revascularization were not significantly different between the groups. Equivalence of 2-year MACE rates was also seen in all examined subgroups. CONCLUSION: Shortened procedural duration and reduction of coronary dissections were observed with planned RA for selected lesions. However, this strategy does not affect long-term clinical outcomes.

Relationship between peri-strut low intensity areas and vascular healing response after everolimus-eluting bioresorbable scaffold implantation: An optical coherence tomography study.

BACKGROUND: Peri-strut low intensity areas (PLIA) surrounding metallic coronary stent struts on optical coherence tomography (OCT) images have been histologically related to delayed healing and inflammation, and have been associated with neointimal proliferation. The relationship between PLIA and vascular healing response after bioresorbable scaffold (BRS) implantation remains unclear. METHODS: This study includes 38 consecutive patients (50 scaffolds) evaluated using OCT 12 months after BRS implantation. Mean and percent neointimal area were quantified. A PLIA was defined as a peri-strut region with an homogenous lower intensity appearance than the surrounding tissue on OCT images without significant signal attenuation. Cross sections were scored as follows: score 0, no PLIA; score 1, <1 quadrant; score 2, ≥1 but <2 quadrants; score 3, ≥2 quadrants but <3 quadrants; and score 4, ≥3 quadrants. Scaffolds were divided into two groups (PLIA+ and PLIA-) based on the presence or absence of any PLIA in the scaffold segment. RESULTS: The frequency of any PLIA within the scaffold segment was 70.0%. The median PLIA score per scaffold was 0.51 (interquartile range 0-1.07). Using both scaffold- and frame-level analysis, a significant positive correlation was observed between PLIA score and both mean and percent neointimal area. Mean and percent neointimal area were significantly higher in the PLIA+ group than in the PLIA- group (1.95±0.65mm2 vs. 1.51±0.27mm2, p<0.01 and 24.0±7.0% vs. 17.4±3.6%, p<0.01, respectively). CONCLUSION: The presence and extent of PLIA on OCT imaging after BRS implantation appears to be significantly associated with neointimal formation.

Neointimal response to everolimus-eluting bioresorbable scaffolds implanted at bifurcating coronary segments: insights from optical coherence tomography.

Heterogeneity of neointimal thickness is observed after drug-eluting stents implantation in bifurcation lesions (BL). We evaluated the vascular response of everolimus-eluting bioresorbable scaffold (BRS) struts deployed at BL using optical coherence tomography (OCT). 50 patients (64 scaffolds) underwent follow-up OCT after BRS implantation. Cross-sectional areas of each BL with a side branch more than 1.5 mm were analyzed using OCT every 200 µm. All images were divided into three regions according to shear stress: the 1/2 circumference of the vessel opposite to the ostium (OO), the vessel wall adjacent to the ostium (AO) and the side-branch ostium (SO). The %uncovered strut and the averaged neointimal thickness (NIT) were calculated. Overall, there were significant differences in both NIT and %uncovered strut among the three regions (OO, 119.2 ± 68.5 µm vs. AO, 94.2 ± 35.7 µm vs. SO, 80.5 ± 41.4 µm, p = 0.03; OO, 0.4 %vs. AO, 1.4 %vs. SO, 4.8 %, p = 0.02). Scaffolds were divided into two groups: a large-ratio side-branch group (LRSB; n = 32) and a small-ratio side-branch group (SRSB; n = 32), based on the median value of the ratio of the diameter of side branch ostium (Ds) to that of the main branch (Dm). In the LRSB alone, there were significant differences in both NIT and %uncovered strut among the three regions (OO, 128.0 ± 61.1 µm vs. AO, 97.3 ± 34.3 µm vs. SO, 75.9 ± 39.4 µm, p < 0.01; OO, 0.3 % vs. AO, 2.3 % vs. SO, 8.7 %, p < 0.01). After BRS implantation in BL, neointimal response was pronounced at the vessel wall opposite to the side branch ostium, especially in those with large side branches.