Longitudinal Neointimal Distribution Pattern After Everolimus-Eluting Stent Implantation: Insights From Optical Coherence Tomography Study

BACKGROUND/PURPOSE

Everolimus-eluting stents (EES) are established as latest generation drug eluting stents. However, optical coherence tomography (OCT) assessment of neointimal distribution after EES implantation is lacking. We aimed to assess the longitudinal neointimal distribution pattern after EES implantation using OCT.

METHODS

Data from 3 prospective studies (HEAL-EES, REVER and RESERVOIR), including patients with EES implantation and OCT follow-up study, were merged. Analyzed stents were divided into 3 segments of equal length (distal, medial, proximal). Longitudinal neointimal distribution patterns were compared between the 3 segments using generalized estimating equation. Neointimal thickness (NIT), neointimal area obstruction, and uncovered or malapposed struts were analyzed.

RESULTS

In total, 86 patients (92 lesions) were analyzed. Time of OCT follow-up was 9.0 ± 1.5 months. NIT was 101.7 ± 65.4 μm and neointimal obstruction area was 12.2 ± 7.6%. The number of assessed struts was the same in all three segments. NIT tended to be higher at the medial segment (108.8 ± 71.1 μm) compared to distal (103.0 ± 63.4 μm) and proximal (93.3 ± 61.1 μm) (p = 0.076). Neointimal area obstruction was significantly different between the 3 segments (12.4 ± 7.5% [distal], 13.1 ± 7.7% [medial], 11.1 ± 7.5% [proximal]; p = 0.037). In the proximal segment, there was a significantly higher frequency of uncovered struts compared to medial and distal segments (3.9% vs. 2.1% vs. 2.5%, p = 0.009). The distribution of malapposed struts was not significantly different.

CONCLUSIONS

Distribution of neointimal hyperplasia seems to be different between stent segments, being higher in the medial segment as compared to proximal and distal. Whether this may reflect a response to local pre-interventional plaque burden centrally covered by the stent should be confirmed in a future study.

MANUSCRIPT SUMMARY

As optical coherence tomography based assessment of neointimal distribution after everolimus-eluting stent implantation is lacking, we analyzed data of 86 patients (92 lesions) from 3 prospective trials to evaluate neointimal distribution in distal, medial and proximal stent segments. Neointimal hyperplasia seemed to be different between the three segments, with a higher burden in the medial stent segment. Whether this reflects a response to local pre-interventional plaque burden centrally covered by the stent should be confirmed in a future study.

Impact of hyperuricemia on clinical outcomes after percutaneous coronary intervention for in-stent restenosis

Background

There have been limited data on the impact of hyperuricemia on long-term clinical outcomes after percutaneous coronary intervention (PCI) for in-stent restenosis (ISR).

Methods

From January 2009 to July 2015, 317 patients who underwent repeat PCI for ISR were divided into two groups: patients with normal serum uric acid (UA) levels (normal UA group) and patients with higher serum UA levels (higher UA group). The higher UA group included patients with serum UA levels > 6.8 mg/dL or patients who were taking anti-hyperuricemic medication.

Results

During a median follow-up period of 1088 days, the cumulative incidence rates of major adverse event (MAE), including a composite of all-cause death, non-fatal myocardial infarction, and any revascularization, were similar between the two groups (higher UA 36.4% vs. normal UA 29.9%, p = 0.389, log-rank p = 0.367). Follow-up angiographic data showed similar outcomes of late lumen loss (0.8 ± 0.9 mm vs. 0.8 ± 1.1 mm, p = 0.895) and binary restenosis rate (28.1% vs. 34.7%, p = 0.622). Multivariate Cox regression analysis indicated higher levels of low-density lipoprotein cholesterol (hazard ratio [HR] 1.011, 95% confidence interval [CI] 1.003–1.019, p = 0.006) and lower left ventricular ejection fraction (HR 0.972, 95% CI 0.948–0.996, p = 0.022), but not UA levels, to be the independent risk predictors of MAE.

Conclusion

Hyperuricemia is not associated with poor clinical outcomes after repeat PCI for ISR lesions.

Electronic supplementary material

The online version of this article (10.1186/s12872-018-0840-2) contains supplementary material, which is available to authorized users.

Difference in clinical presentations and related angiographic findings among early, late, and very late sirolimus-eluting stent failures requiring target lesion revascularization

BACKGROUNDS

The difference in clinical presentations (acute coronary syndrome [ACS] and stable coronary artery disease [SCAD]) and related angiographic morphologies of sirolimus-eluting stent (SES) failure requiring target lesion revascularization (TLR) during early-term (<1year), late-term (1-5years), and very late-term periods (>5years) remains unknown.

METHODS

Among 4484 lesions undergoing SES implantation, clinically-driven TLR was performed on 105 lesions during early-term, 169 lesions during late-term, and 147 lesions during very late-term period. Angiographic morphological patterns were divided into focal or non-focal patterns and stent-edge or stent-body patterns.

RESULTS

The proportion of ACS substantially increased in very late TLR lesions (57.1%) from early (40.0%, p=0.01) and late TLR lesions (36.7%, p<0.001). The proportions of both stent-edge and non-focal patterns were higher in very late TLR lesions than in early and late TLR lesions. Although the stent-edge pattern tended to be more prevalent in SCAD lesions than in ACS lesions during the early- and late-term periods, it was more frequently observed in ACS lesions than in SCAD lesions during the very late-term period (65.5% vs. 47.6%, p=0.04). The non-focal pattern was more frequent in ACS lesions than in SCAD lesions during all 3 periods. However, the proportion of the non-focal pattern in ACS lesions was extremely high during the very late-term (90.5%) compared with the early- (47.6%, p<0.001) and late-term periods (48.4%, p<0.001).

CONCLUSIONS

Stent-related ACS became more common beyond 5years after SES implantation. Stent-edge and non-focal patterns were the main angiographic morphologies of very late SES failure, particularly causing ACS.

Usefulness of Intracoronary Brachytherapy for Patients With Resistant Drug-Eluting Stent Restenosis

In-stent restenosis (ISR) remains a concern even in the drug-eluting stent (DES) era and carries a high risk of recurrence. Brachytherapy is being used as an alternative treatment for resistant ISR, yet the safety and efficacy of this approach has not been well studied. We analyzed the outcomes of 101 patients who underwent coronary brachytherapy for resistant DES ISR. Baseline demographic, clinical, procedural, and outcome data were collected by phone and from electronic records. Comorbidities and overt cardiovascular disease were highly prevalent. Median previous stent layers were 2 with a maximum of 5 layers. Procedural angiographic success rate was 97% and median time to discharge was 1 day after brachytherapy. The primary outcome of target vessel revascularization was 24% at 1 year, 32% at 2 years, and 42% at 3 years. The rate of nonfatal myocardial infarction was 0% at 1 year, 3.5% at 2 years, and 6% at 3 years. The rate of all-cause mortality was 8.5% at 1 year, 12% at 2 years, and 16% at 3 years. We observed only 1 case of late stent thrombosis. After multivariable adjustment, female gender (hazard ratio 2.37, 95% confidence interval 1.02 to 5.52, p = 0.04) and diffuse ISR pattern (hazard ratio 2.95, 95% confidence interval 1.21 to 7.17, p = 0.01) were independently associated with the primary outcome. In conclusion, brachytherapy is feasible for the treatment of resistant DES ISR and is associated with high immediate procedural success and reasonable efficacy in a complex patient population. This approach might be used as an alternative for these patients.

Initial and late efficacy of everolimus-eluting stents for small and non-small coronary lesions from evaluating delayed late loss study

The aim of the present study was to evaluate the long-term outcomes at 2 years in patients in whom everolimus-eluting stents (EESs) were implanted in small and non-small vessels. A small vessel is an important risk factor for restenosis with BMSs, even in the first generation DESs. The 690 patients with 690 lesions implanted with an EES were enrolled and divided into two groups by vessel reference diameter (RD): >2.5 mm for non-small vessels (Non-S-group) and ≤2.5 mm for small vessels (S-group). Two years later, the 365 patients with no restenosis at 8 months who underwent angiography were enrolled into the late catch-up study. At the initial 8-month follow-up, the rates of restenosis and target lesion revascularization (TLR) of both groups were not significantly different (restenosis 3.9 vs 6.5%, p = 0.17; TLR 3.9 vs 6.5%, p = 0.17). At the late 2-year follow-up, there were no significant differences in the late loss (0.36 ± 0.66 vs 0.34 ± 0.50 mm, p = 0.14), net gain (1.50 ± 0.75 vs 1.26 ± 0.60 mm, p = 0.39), late catch-up restenosis rate (5.1 vs 3.4%, p = 0.38), TLR (4.9 vs 2.7%, p = 0.40), and delayed late loss (0.14 ± 0.58 vs 0.15 ± 0.49 mm, p = 0.10) between both groups. There is no correlation between delayed late loss and RD in all patients(r = -0.009) and in AMI patients (r = -0.004). These results demonstrate that the initial and late catch-up restenosis rates of small coronary vessels with EES placement were excellent, the same as for non-small coronary vessels. We suggest that involvement of small coronary arteries may not be a risk factor for restenosis and results of stenting for small coronary arteries with EES placement were excellent.

Propensity-Score Matched Comparison of Midterm Angiographic Outcomes of Sirolimus- Versus Everolimus- and Biolimus-Eluting Stents for De Novo Coronary Stenosis

We conducted propensity-score matched comparisons of midterm angiographic outcomes of sirolimus (SES) versus either everolimus- (EES) or biolimus- (BES) eluting stents after placements for coronary stenosis in a daily practice environment since previous randomized trials did not demonstrate the superiority of EES and BES over SES in terms of midterm angiographic outcomes.The present study was a non-randomized, retrospective, and lesion-based study, recruiting angiographically followed-up lesions within 550 days after successful and elective SES (n = 1793), EES (n = 1303), or BES (n = 324) placement for de novo native coronary stenosis during the period from August 2004 to January 2014 at 6 institutes. The endpoint, as an angiographic surrogate marker of clinical efficacy, was the distribution of in-stent follow-up percent diameter stenosis (%DS) which comprised the percentages of 1) follow-up %DS < 20 and 2) follow-up %DS > 50. Propensityscore matched analyses were conducted to adjust 21 baselines.In 1215 baseline adjusted lesions, the endpoints in the EES group [1) 74.1%, and 2) 4.6%] were significantly different from those in the SES group [57.9%; P < 0.001, 7.2%; P = 0.006, respectively). In 307 baseline adjusted lesions, the endpoints in the BES group [1) 80.5%, 2) 2.0%] were significantly different from those in the SES group [59.3%; P < 0.001, 2) 8.1%; P = 0.001, respectively].The present study is the first to confirm the superiority of midterm angiographic outcomes after the placement of EES and BES over SES for de novo coronary stenosis in a clinical setting.

SYNTAX Score-II Predicts Long-Term Mortality in Patients Who Underwent Left Main Percutaneous Coronary Intervention Treated With Second-Generation Drug-Eluting Stents

The aim of this study was to evaluate the capacity of the SYNTAX Score-II (SS-II) to predict long-term mortality in patients undergoing left main percutaneous coronary intervention (LM-PCI) treated with second-generation drug-eluting stents (DES).Data from 487 consecutive patients with de novo left main coronary artery disease undergoing PCI were retrospectively studied. The patients were divided into tertiles according to the SS-II: low SS-II tertile (SS-II ≤ 22), intermediate SS-II tertile (SS-II of 23 to 30), and high SS-II tertile (SS-II ≥ 30). The survival curves were estimated by the Kaplan-Meier method. Univariate and multivariate Cox proportional hazard regression analyses were performed to evaluate the possible associations between the SS-II and the rates of long-term mortality. The predictive ability of the SS-II for mortality was assessed and compared with the SYNTAX score (SS) alone by an area under the receiver operator curve (AUC).The overall SS-II was 27.3 ± 9.1. At a mean follow-up of 5.1 years, the long-term mortality was 6.0%. The rates of mortality were 2.4%, 3.4%, and 11.6%, respectively (P < 0.0001) in the low, intermediate, and high SS-II tertiles. The cardiac mortality rates were 1.8%, 1.4%, and 8.1%, respectively (P = 0.002) among patients in the 3 groups. By multivariate analysis, SS-II was an independent predictor of the long-term mortality (hazard ratio: 1.56, 95% confidence interval: 1.05 to 2.32; P = 0.03). The AUC demonstrated a substantially higher predictive accuracy of the SS-II for mortality compared with the SS alone (AUC was 0.689 and 0.596, respectively).In patients with LM-PCI treated with a second-generation DES, the SS-II is an independent predictor of long-term mortality and demonstrates a superior predictability compared with the SS alone.