Contemporary Management of Severely Calcified Coronary Lesions

Coronary artery calcification is increasingly prevalent in our patient population. It significantly limits the procedural success of percutaneous coronary intervention and is associated with a higher risk of adverse cardiovascular events both in the short-term and long-term. There are several modalities for modifying calcified plaque, such as balloon angioplasty (including specialty balloons), coronary atheroablative therapy (rotational, orbital, and laser atherectomy), and intravascular lithotripsy. We discuss each modality’s relative advantages and disadvantages and the data supporting their use. This review also highlights the importance of intravascular imaging to characterize coronary calcification and presents an algorithm to tailor the calcium modification therapy based on specific coronary lesion characteristics.

Imaging and 2-year clinical outcomes of thin strut sirolimus-eluting bioresorbable vascular scaffold: The MeRes-1 extend trial

OBJECTIVES

This study explores the safety and efficacy of thin strut MeRes100 sirolimus-eluting bioresorbable vascular scaffold (BRS) in patients with de novo coronary artery lesions.

BACKGROUND

In interventional cardiology, the emergence of BRS technology is catalyzing the next paradigm shift.

METHODS

The MeRes-1 Extend was a multicenter, prospective, single-arm, open-label study enrolling 64 patients in Spain, Macedonia, Brazil, South Africa, Malaysia, and Indonesia. The safety endpoint was major adverse cardiac events (MACE) which composed of cardiac death, myocardial infarction (MI), and ischemia-driven target lesion revascularization (ID-TLR). The imaging efficacy endpoint was mean in-scaffold late lumen loss (LLL) evaluated by quantitative coronary angiography (QCA). Optical coherence tomography (OCT) imaging was performed at baseline and 6-month follow-up.

RESULTS

A total of 69 target lesions were identified in 64 enrolled patients (mean age 58.30 ± 9.02 years). Of the treated lesions, 49 (71.01%) lesions were of type B2/C. Procedural and device success was achieved in 64 and 62 patients, respectively. At 2-year follow-up, MACE was reported in one patient (1.61%) in the form of ID-TLR. There was no case of MI, cardiac death or scaffold thrombosis through 2-year. In a subset of 32 patients, paired QCA showed mean in-scaffold LLL of 0.18 ± 0.31 mm at 6-month follow-up. In a subset of 21 patients, OCT revealed 97.95 ± 3.69% strut coverage with mean scaffold area of 7.56 ± 1.79 mm² and no evidence of strut malapposition.

CONCLUSIONS

The clinical and imaging outcomes of MeRes-1 Extend trial demonstrated favorable safety and efficacy of MeRes100 sirolimus-eluting BRS in patients with de novo coronary artery lesions.

Calcium Modification Techniques in Complex Percutaneous Coronary Intervention

Percutaneous coronary intervention is the most common mode of revascularization and is increasingly undertaken in high-risk subsets, including the elderly. The presence of coronary artery calcification is increasingly observed and significantly limits technical success. The mechanisms for this are multi-factorial, including increased arterial wall stiffness and impaired delivery of devices, leading to suboptimal stent delivery, deployment, and expansion which are harbingers for increased risk of in-stent restenosis and stent thrombosis. Although conventional balloon pretreatment techniques aim to mitigate this risk by modifying the lesion before stent placement, many lesions remain resistant to conventional strategies, due to the severity of calcification. There have been several substantial technological advancements in calcium modification methods in recent years, which have allowed improved procedural success with low periprocedural complication rates. This review will summarize the current adjunctive modification technologies that can be employed to improve technical outcomes in percutaneous coronary intervention in calcific disease and the evidence supporting these tools.

Performing percutaneous coronary interventions with predilatation using non-compliant balloons at high-pressure versus conventional semi-compliant balloons: insights from two randomised studies using optical coherence tomography

Introduction

Stent underexpansion is a predictor of in-stent-restenosis and stent thrombosis. Semi-compliant balloons (SCBs) are generally used for lesion preparation. It remains unknown whether routine predilatation using non-compliant balloons (NCBs) improves stent expansion in ordinary coronary lesions.

Methods

The PREdilatation by high-pressure NC balloon catheter for better vessel preparation and Optimal lesion preparation with non-compliant balloons for the implantation of bioresorbable vascular scaffolds studies randomised patients presenting with stable coronary artery disease or non-ST-elevation myocardial infarction requiring stent implantation to lesion preparation using NCBs versus SCBs. Stent expansion index (SEI-minimal luminal area/mean luminal area on optical coherence tomography) and periprocedural complications were compared.

Results

We enrolled 104 patients: 53 patients (54 lesions) vs 51 patients (56 lesions) to the NCB and SCB groups, respectively. Predilatation pressure was higher in the NCB group (24±7 atmospheres (atm) vs 14±3 atm, p<0.0001). Postdilatation using NCBs was performed in 41 (76%) lesions vs 46 (82%) lesions pretreated with NCBs versus SCBs (p=0.57). Similar pressures were used for postdilatation with NCB in both groups (23±8 atm vs 23±9 atm, p=0.65). SEI after stent implantation was 0.88±0.13 in the NCB vs 0.85±0.14 in the SCB group (p=0.18). After postdilatation, SEI increased to 0.94±0.13 in the NCB group vs 0.88±0.13 in the SCB group (p=0.02). No relevant complications occurred.

Conclusions

In simple coronary lesions, predilatation/postdilatation with NCBs at high pressures appears to result in better scaffold and stent expansion. Using SCBs only for predilatation might lead to inadequate stent expansion and postdilatation with NCBs might only partially correct this. Predilatation and postdilatation using NCBs at high pressure is safe.

Trial registration number

ClinicalTrials.gov no. NCT03518645.

Routine use of optical coherence tomography in bioresorbable vascular scaffold implantation: insights on technique optimization and long-term outcomes

BACKGROUND

Data from prior studies have shown increased risk of adverse outcomes with bioresorbable vascular scaffolds (BVS) compared with drug-eluting stents.

OBJECTIVE

The objective of this study was to study the long-term outcomes with routine use of optical coherence tomography (OCT) for optimization of BVS implantation.

PATIENTS AND METHODS

Clinical, procedural, and outcome data were collected for all patients who received ABSORB BVS between February 2014 and March 2016 in our tertiary center (n=86). Preimplantation and postimplantation OCT was performed in all cases. Outcomes of interest included acute device success and long-term clinical outcomes including cardiac mortality, target vessel myocardial infarction, ischemia-driven target lesion revascularization, and scaffold thrombosis.

RESULTS

A total of 86 patients were included (106 lesions, 115 BVS implanted). Mean age was 59.5±10.9 years, with 66% men. Mean lesion length was 25.2±15.6 mm and mean reference vessel diameter was 3.42±0.45 mm. Type B2/C accounted for 40% of the lesions. All scaffold implantations followed the predilation, proper sizing, and postdilation strategy. Of the 115 scaffolds analyzed, 11 (9.5%) required further intervention based on prespecified OCT endpoints. On multivariate regression analysis, complex coronary lesion (type B2/C) was the single independent predictor of OCT use in scaffold optimization (odds ratio=6.3, 95% confidence interval: 1.3-7.8, P=0.02). At a mean follow-up duration of 31±7.1 months, no cases of cardiac mortality, target vessel myocardial infarction, ischemia-driven target lesion revascularization, or scaffold thrombosis were reported.

CONCLUSION

Operators may consider OCT use for optimization of BVS implantation particularly in patients with complex coronary lesions.

Effect of Post-Dilatation Following Primary PCI With Everolimus-Eluting Bioresorbable Scaffold Versus Everolimus-Eluting Metallic Stent Implantation: An Angiographic and Optical Coherence Tomography TROFI II Substudy

OBJECTIVES

This study sought to investigate the effect of post-dilatation on angiographic and intracoronary imaging parameters in the setting of primary percutaneous coronary intervention comparing the everolimus-eluting bioresorbable scaffold (BRS) with the everolimus-eluting metallic stent (EES).

BACKGROUND

Routine post-dilatation of BRS has been suggested to improve post-procedural angiographic and subsequent device-related clinical outcomes.

METHODS

In the ABSORB STEMI TROFI II trial, 191 patients with ST-segment elevation myocardial infarction were randomly assigned to treatment with BRS (n = 95) or EES (n = 96). Minimal lumen area and healing score as assessed by optical coherence tomography at 6 months were compared between BRS- and EES-treated patients stratified according to post-dilatation status.

RESULTS

Primary percutaneous coronary intervention with post-dilatation was performed in 48 (50.5%) BRS- and 25 (25.5%) EES-treated lesions. There were no differences in baseline characteristics and post-procedural minimal lumen diameter between groups. In the BRS group, lesions with post-dilatation were associated with a trend toward a smaller minimal lumen area at 6 months (5.07 ± 1.68 mm² vs. 5.72 ± 1.77 mm²; p = 0.09) and significantly larger angiographic late lumen loss (0.28 ± 0.34 mm vs. 0.12 ± 0.25 mm; p = 0.02), whereas no difference was observed in the EES arm (5.46 ± 2.18 mm² vs. 5.55 ± 1.77 mm²; p = 0.85). The neointimal healing score was low and comparable between groups with and without post-dilation (BRS: 1.55 ± 2.61 vs. 1.92 ± 2.17; p = 0.48; EES: 2.50 ± 3.33 vs. 2.90 ± 4.80; p = 0.72).

CONCLUSIONS

In the setting of selected patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention with BRS or EES, post-dilatation did not translate into larger lumen area or improved arterial healing at follow-up. (ABSORB STEMI: The TROFI II; NCT01986803).

Everolimus-eluting bioresorbable vascular scaffold in daily clinical practice: A single-centre experience

Background

Recent evidence has raised concerns regarding the safety of the everolimus-eluting bioresorbable vascular scaffold (E-BVS) (Absorb, Abbott Vascular, Santa Clara, CA, USA). Following these data, the use of this device has diminished in the Netherlands; however, daily practice data are limited. Therefore we studied the incidence of safety and efficacy outcomes with this device in daily clinical practice in a single large tertiary centre in the Netherlands.

Methods

All E‑BVS treated patients were included in this analysis. The primary endpoint was target lesion failure (TLF), a composite of cardiac death, target vessel non-fatal myocardial infarction (TV-MI) and clinically-driven target lesion revascularisation (TLR). The secondary endpoint was the incidence of definite scaffold thrombosis.

Results

Between October 2013 and January 2017, 105 patients were treated with 147 E‑BVS. This population contained 42 (40%) patients with diabetes mellitus and 43 (40.9%) undergoing treatment for acute coronary syndrome, and thus represents a high-risk patient cohort. Mean follow-up was 19.8 months. Intravascular imaging guidance during scaffold implantation was used in 64/105 (43.5%) patients. The primary endpoint (TLF) occurred in 3 (2.9%) patients. All-cause mortality and cardiac mortality occurred in 2 (2%) and 0 (0%) patients respectively. TV-MI occurred in 2 patients (1.9%): both were periprocedural and not related to the BVS implantation. TLR occurred in 1 patient (1.0%) during follow-up. No definite scaffold thrombosis occurred during follow-up.

Conclusion

This single-centre study examining the real-world experience of E‑BVS implantation in a high-risk population shows excellent procedural safety and long-term clinical outcomes.

Optical coherence tomography guidance during bioresorbable vascular scaffold implantation

Bioresorbable vascular scaffold (BRS) represent a revolutionary concept in interventional cardiology. After initial enthusiasm, recent real world registries, including patients with increasing lesion complexity, reported not trivial rates of scaffold thrombosis (ScT). The importance of correct patients selection as well as technical aspects during BRS implantation procedures has been highlighted in several studies suggesting that the high rate of ScT might be related to uncorrected patients/lesions selection together with underutilization of intracoronary imaging guidance leading to suboptimal BRS implantation. The high-resolution power together with the lack of shadowing observed beyond polymer struts makes optical coherence tomography (OCT) the optimal imaging technique to guide BRS implantation and identifies eventually scaffolds failures.

Long-term clinical results of bioresorbable absorb scaffolds using the PSP-technique in patients with and without diabetes

OBJECTIVES

We evaluated clinical results up to 36 months after implantation of Absorb BVS using PSP-technique and compared the outcome of patients with and without diabetes mellitus.

BACKGROUND

Absorb II demonstrated that interventional treatment of coronary artery disease with bioresorbable vascular scaffolds (BVS) without proper PSP-technique (pre-dilation, proper sizing, and post-dilation) is associated with an increased thrombotic risk, even in simple lesions.

METHODS

In this prospective study 319 patients with 420 lesions were enrolled and treated with the Absorb BVS. Pre-dilation was mandatory and post-dilation with a high-pressure balloon was performed in patients with a scaffold length >12 mm. Patients were clinically followed up to 3 years. Primary outcome measure was the device-oriented endpoint (DoCE) defined as cardiac death, myocardial infarction not clearly related to a non-target vessel and target lesion revascularization.

RESULTS

DoCE was 5.0%, 7.1%, and 10.0% after 12, 24, and 36 months for the total population. Rate of scaffold thrombosis was 0.5%, 0.8%, and 1.4% after 12, 24, and 36 months. Rate of DoCE was higher in the diabetic subgroup with 9.1%, 12.6%, and 12.9% after 12, 24, and 36 months compared with 4.0% (P = 0.13), 5.6% (P = 0.05), and 9.9% (P = 0.20) in patients without diabetes mellitus.

CONCLUSIONS

Patients treated with the Absorb BVS using the PSP-technique show good results up to 3 years with a low rate of scaffold thrombosis. Patients suffering from diabetes mellitus have an increased rate of DoCE compared with non-diabetic patients.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov_NCT02162056.

Bioresorbable vascular scaffolds in coronary chronic total occlusions revascularization: safety assessment related to struts coverage and apposition in 6-month OCT follow-up

Beneficial properties of bioresorbable vascular scaffolds (BVS) regarding to vasomotility restoration and no caging of the vessel make them attractive devices in chronic total occlusions (CTO) revascularization. However, more evidence is needed attending to their use in this specific setting. We aim to determine feasibility and safety of BVS use in CTO revascularization attending to struts coverage and apposition, as well as re-stenosis and stent thrombosis (ST) rates. 29 BVS were deployed in 9 CTO lesions revascularization (mean J-CTO score ≥3) with an acute procedural success rate of 100%. Clinical and angiographic follow-up was performed 6 months later, including intracoronary analyses from optical coherence tomography (OCT) images. 44,723 struts were analyzed within the total 636 mm of scaffolded vessel. Mean length scaffolded per lesion was 70.66 ± 31.01 mm with a mean number of 3.22 BVS. 2051 struts (4.59%) were identified as uncovered, being most of them (98.4%) neither malapposed nor disrupted. Mean thickness of struts' coverage was 0.13 ± 0.05 mm. Incomplete strut apposition (ISA) percentage was 0% as no malapposed struts were detected and 134 struts were identified as disrupted, which represents a 0.29% from the total. Mean vessel, scaffold, and lumen diameters were 3.87 ± 0.51, 2.97 ± 0.49, and 2.68 ± 0.50 mm, respectively. Neither in-stent re-stenosis nor ST was detected. During follow-up, none of our patients died, suffered from stroke or needed target lesion revascularization. Clinical and angiographic 6-month follow-up (including OCT analyses) of BVS in CTO revascularization suggests their effectiveness and safety, even in very complex chronic occluded lesions. Nevertheless, more evidence is needed.

Two-year outcomes of bioresorbable vascular scaffold versus drug-eluting stents in coronary artery disease: a meta-analysis

BACKGROUND

Data regarding long-term clinical outcomes with everolimus-eluting bioresorbable vascular scaffold (BVS) versus second-generation drug-eluting stents (DES) are scarce.

METHODS

We searched online databases until October 2016 for studies comparing BVS versus DES reporting outcomes at 2 years of follow-up. We performed a meta-analysis comparing BVS with DES across the spectrum of coronary artery disease (CAD). Random effects model OR was calculated for outcomes of interest including device-oriented composite events (DOCE; defined as composite of cardiac mortality, target vessel myocardial infarction (TV-MI), and ischaemia-driven target lesion revascularisation (TLR)), all-cause mortality, definite stent thrombosis, TV-MI and TLR.

RESULTS

A total of 2360 patients enrolled in five studies met criteria for inclusion in this analysis. At 2 years, BVS was associated with higher rates of DOCE (6.9% vs 4.5%, OR=1.53; 95% CI 1.06 to 2.23; p=0.02), absolute risk increase (ARI) 2.4%, relative risk increase (RRI) 53%, TV-MI (4% vs 1.8%, OR=1.94; 95% CI 1.02 to 3.67; p=0.04), ARI 2.2%, RRI 122% and definite stent thrombosis (2.1% vs 0.6%, OR=3.39; 95% CI 1.46 to 7.88; p=0.005), ARI 1.5%, RRI 250% compared with DES. No differences in all-cause mortality (OR=0.86; 95% CI 0.26 to 2.81; p=0.80) and TLR (OR=1.44; 95% CI 0.81 to 2.54; p=0.21) were observed between both groups.

CONCLUSIONS

BVS may be associated with worse long-term clinical outcomes compared with DES. Randomised clinical trials are encouraged to expeditiously report long-term safety and efficacy outcomes and identify predictors of adverse events with BVS compared with DES.

Bioresorbable scaffolds compared with everolimus-eluting stents for the treatment of chronic coronary total occlusion: clinical and angiographic results of a matched paired comparison

OBJECTIVES

Data on bioresorbable vascular scaffolds for recanalization of chronic total occlusions (CTOs) are limited. We compared the bioresorbable scaffold Absorb with everolimus-eluting stents for the treatment of true CTO.

METHODS

After recanalization of CTO, 15 lesions treated with the bioresorbable scaffold Absorb were matched with 15 lesions receiving everolimus-eluting stent (EES) (http://www.clinicaltrials.gov NCT02162082). Match criteria were presence of diabetes mellitus, total device length and maximal device diameter. Angiographic follow-up was scheduled after 9 months and clinical follow-up after 12 months. Dual antiplatelet therapy was administered for 12 months. Quantitative coronary analysis was carried out before and after implantation and at angiographic follow-up. All lesions were predilated. The Absorb scaffolds and drug-eluting stents were carefully placed and postdilatated with high-pressure balloons. Patients received dual antiplatelet therapy for 12 months. The baseline characteristics were similar between both the groups. The mean scaffold length was 81.7±29.1 versus 79.3±27.4 mm for the mean stent length (P=0.82). In-device late lumen loss at the 9-month follow-up was 0.38±0.47 versus 0.46±0.60 mm (P=0.69). The device-oriented composite endpoint was similar in both groups, with 6.7% in the Absorb-group versus 13.3% in the EES group because of target lesion revascularization (P=0.54).

CONCLUSION

In CTOs, the use of a bioresorbable scaffold Absorb after recanalization showed similar 9-month angiographic and 12-month clinical results compared with an EES with 12 months of dual antiplatelet therapy.

Optical coherence tomography guidance for percutaneous coronary intervention with bioresorbable scaffolds

BACKGROUND

The effect of optical coherence tomography (OCT) guidance on the implantation strategy during all phases of percutaneous coronary intervention (PCI) with bioresorbable vascular scaffolds (BVSs) in a real-world scenario has been poorly investigated.

METHODS

Consecutive patients undergoing BVS implantation at our institution were included in this registry. Frequency-domain OCT pullbacks were performed at the operator's discretion during all phases of BVS implantation procedures to optimize preparation of lesions, confirm BVS size, and optimize expansion and apposition of scaffolds.

RESULTS

Between September 2012 and July 2015, 203 BVSs were implanted in 101 consecutive patients at our institution (2.01 BVSs/patient). In 66 patients, the procedure was performed under OCT guidance. In the OCT subgroup, 66 (77.6%) of the 85 treated lesions were complex (B2/C AHA/ACC type). Overall, 147 OCT pullbacks were performed and 72/147 (49.0%) pullbacks indicated the need for changing strategy. After angiography-only-guided optimisation of BVS in 27 (31.8%) lesions, an OCT examination prompted performance of a second post-expansion. This resulted in an increase in the minimal scaffold area (5.5 to 6.3mm(2), p=0.004) and a decrease in the incomplete scaffold apposition area (1.1 to 0.6mm(2), p=0.082), with no new stent fractures. When the population was divided according to the time of BVS implantation, an initial learning adaptation became evident, with the number of OCT-guided changes in strategy significantly decreasing between the initial and final time periods (p=0.017).

CONCLUSIONS

OCT guidance for BVS implantation significantly affects the procedural strategy, with favourable effects on acute results and the learning curve.

"Assessment of effectiveness and security in high pressure postdilatation of bioresorbable vascular scaffolds during percutaneous coronary intervention. Study in a contemporary, non-selected cohort of Spanish patients"

OBJECTIVES

To determine security and benefits of high pressure postdilatation (HPP) of bioresorbable vascular scaffolds (BVS) in percutaneous coronary intervention (PCI) of complex lesions whatever its indication is.

BACKGROUND

Acute scaffold disruption has been proposed as the main limitation of BVS when they are overexpanded. However, clinical implications of this disarray are not yet clear and more evidence is needed.

METHODS

A total of 25 BVS were deployed during PCI of 14 complex lesions after mandatory predilatation. In all cases HPP was performed with NC balloon in a 1:1 relation to the artery. After that, optical coherence tomography (OCT) analyses were performed.

RESULTS

Mean and maximal postdilatation pressure were 17±3.80 and 20 atmospheres (atm) respectively. Postdilatation balloon/scaffold diameter ratio was 1.01. A total of 39,590 struts were analyzed. Mean, minimal and maximal scaffold diameter were respectively: 3.09±0.34mm, 2.88±0.31mm and 3.31±0.40mm. Mean eccentricity index was 0.13±0.05. ISA percentage was 1.42% with a total of 564 malapposed struts. 89 struts were identified as disrupted, which represents a percentage of disrupted struts of 0.22%. At 30days, none of our patients died, suffered from stroke, stent thrombosis or needed target lesion revascularization (TLR).

CONCLUSIONS

NC balloon HPP of BVS at more than 17atm (up to 20atm) is safe during PCI and allows to achieve better angiographic and clinical results.

Deploying bioresorbable vascular scaffolds--tardus, altius, amplius!!

Current generation bioresorbable vascular scaffolds (BVS) have thick struts and relatively low radial strength; meticulous deployment is required to prevent underexpansion while avoiding stent fracture. The current study suggests safety of very high-pressure (mean 28 atm) post-dilation of BVS with a noncompliant balloon. Duration of inflation and inflation pressure stabilization are important factors that influence the extent of optimal stent expansion and should be studied in future attempts to optimize BVS deployment.