Percutaneous coronary intervention of native coronary artery versus saphenous vein graft in patients with prior coronary artery bypass graft surgery: Rationale and design of the multicenter, randomized PROCTOR trial

BACKGROUND

Patients with prior coronary artery bypass grafting (CABG) frequently require repeat percutaneous revascularization due to advanced age, progressive coronary artery disease and bypass graft failure. Percutaneous coronary intervention (PCI) of either the bypass graft or the native coronary artery may be performed. Randomized trials comparing native vessel PCI with bypass graft PCI are lacking and long-term outcomes have not been reported.

METHODS

PROCTOR (NCT03805048) is a prospective, multicenter, randomized controlled trial, that will include 584 patients presenting with saphenous vein graft (SVG) failure and a clinical indication for revascularization, as determined by the local Heart Team. The trial is designed to compare the clinical and angiographic outcomes in patients randomly allocated in a 1:1 fashion to either a strategy of native vessel PCI or SVG PCI. The primary study endpoint is a 3-year composite of major adverse cardiac events (MACE: all-cause mortality, non-fatal target coronary territory myocardial infarction [MI], or clinically driven target coronary territory revascularization). At 3-years, after evaluation of the primary endpoint, follow-up invasive coronary angiography will be performed. Secondary endpoints comprise individual components of MACE at 1, 3 and 5 years follow-up, PCI-related MI, MI >48 hours after index PCI, target vessel failure, target lesion revascularization, renal failure requiring renal-replacement therapy, angiographic outcomes at 3-years and quality of life (delta Seattle Angina Questionnaire, Canadian Cardiovascular Society Grading Scale and Rose Dyspnea Scale).

CONCLUSION

PROCTOR is the first randomized trial comparing an invasive strategy of native coronary artery PCI with SVG PCI in post-CABG patients presenting with SVG failure.

Routine Pressure Wire Assessment Versus Conventional Angiography in the Management of Patients With Coronary Artery Disease: The RIPCORD 2 Trial

BACKGROUND

Measurement of fractional flow reserve (FFR) has an established role in guiding percutaneous coronary intervention. We tested the hypothesis that, at the stage of diagnostic invasive coronary angiography, systematic FFR-guided assessment of coronary artery disease would be superior, in terms of resource use and quality of life, to assessment by angiography alone.

METHODS

We performed an open-label, randomized, controlled trial in 17 UK centers, recruiting 1100 patients undergoing invasive coronary angiography for the investigation of stable angina or non-ST-segment-elevation myocardial infarction. Patients were randomized to either angiography alone (angiography) or angiography with systematic pressure wire assessment of all epicardial vessels >2.25 mm in diameter (angiography+FFR). The coprimary outcomes assessed at 1 year were National Health Service hospital costs and quality of life. Prespecified secondary outcomes included clinical events.

RESULTS

In the angiography+FFR arm, the median number of vessels examined was 4 (interquartile range, 3-5). The median hospital costs were similar: angiography, £4136 (interquartile range, £2613-£7015); and angiography+FFR, £4510 (£2721-£7415; P=0.137). There was no difference in median quality of life using the visual analog scale of the EuroQol EQ-5D-5L: angiography, 75 (interquartile range, 60-87); and angiography+FFR, 75 (interquartile range, 60-90; P=0.88). The number of clinical events was as follows: deaths, 5 versus 8; strokes, 3 versus 4; myocardial infarctions, 23 versus 22; and unplanned revascularizations, 26 versus 33, with a composite hierarchical event rate of 8.7% (48 of 552) for angiography versus 9.5% (52 of 548) for angiography+FFR (P=0.64).

CONCLUSIONS

A strategy of systematic FFR assessment compared with angiography alone did not result in a significant reduction in cost or improvement in quality of life.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT01070771.

Bioabsorbable polymer drug-eluting stents with 4-month dual antiplatelet therapy versus durable polymer drug-eluting stents with 12-month dual antiplatelet therapy in patients with left main coronary artery disease: the IDEAL-LM randomised trial

BACKGROUND

Improvements in drug-eluting stent design have led to a reduced frequency of repeat revascularisation and new biodegradable polymer coatings may allow a shorter duration of dual antiplatelet therapy (DAPT) after percutaneous coronary intervention (PCI).

AIMS

The Improved Drug-Eluting stent for All-comers Left Main (IDEAL-LM) study aims to investigate long-term clinical outcomes after implantation of a biodegradable polymer platinum-chromium everolimus-eluting stent (BP-PtCr-EES) followed by 4 months DAPT compared to a durable polymer cobalt-chromium everolimus-eluting stent (DP-CoCr-EES) followed by 12 months DAPT in patients undergoing PCI of unprotected left main coronary artery (LMCA) disease.

METHODS

This is a multicentre randomised clinical trial study in patients with an indication for coronary artery revascularisation who have been accepted for PCI for LMCA disease after Heart Team consultation. Patients were randomly assigned in a 1:1 ratio to receive either the BP-PtCr-EES or the DP-CoCr-EES. The primary endpoint was a non-inferiority comparison of the rate of major adverse cardiovascular events (MACE), defined as all-cause death, myocardial infarction, or ischaemia-driven target vessel revascularisation at 2 years.

RESULTS

Between December 2014 and October 2016, 818 patients (410 BP-PtCr-EES and 408 DP-CoCr-EES) were enrolled at 29 centres in Europe. At 2 years, the primary endpoint of MACE occurred in 59 patients (14.6%) in the BP-PtCr-EES group and 45 patients (11.4%) in the DP-CoCr-EES group; 1-sided upper 95% confidence interval (CI) 7.18%; p=0.04 for non-inferiority; p=0.17 for superiority. The secondary endpoint event of BARC 3 or 5 bleeding occurred in 11 patients (2.7%) in the BP-PtCr-EES group and 2 patients (0.5%) in the DP-CoCr-EES group (p=0.02).

CONCLUSIONS

In patients undergoing PCI of LMCA disease, after two years of follow-up, the use of a BP-PtCr-EES with 4 months of DAPT was non-inferior to a DP-CoCr-EES with 12 months of DAPT with respect to the composite endpoint of all-cause death, myocardial infarction or ischaemia-driven target vessel revascularisation.

Intravascular lithotripsy for treatment of calcific coronary lesions in ST elevation myocardial infarction

AIMS

To describe the utility and safety of intravascular lithotripsy (IVL) in the setting of primary percutaneous coronary intervention (PCI) for ST elevation myocardial infarction (STEMI).

METHODS AND RESULTS

We performed a retrospective analysis, across six UK sites of all patients in whom IVL was used for coronary calcium modification of the culprit lesion during primary PCI for STEMI. The 72 patients were included. IVL was used in de-novo culprit lesions in 57 (79%) of cases and culprit in-stent restenoses in 11 (15%) of cases. In four cases (6%) it was used in a newly deployed stent when this was under-expanded due to inadequate calcium modification. Of the 30 cases in which intracoronary imaging was available for stent analysis, the average stent expansion was 104%. Intra-procedural stent thrombosis occurred in one case (1%), and no-reflow in three cases (4%). The 30 day MACE rates were 18%.

CONCLUSION

IVL appears to be feasible and safe for use in the treatment of calcific coronary artery disease in the setting of STEMI.

Acute Treatment and 5-Year Follow-up of Longitudinal Deformation of a Bioresorbable Scaffold

A 46-year-old man with type 1 diabetes underwent percutaneous coronary intervention with bioresorbable scaffold implantation for a long segment of physiologically significant left anterior descending coronary artery disease. The procedure was complicated by longitudinal stent deformation (LSD). The images carry several important educational messages for clinicians. First, as with all stents, LSD is possible in extreme circumstances. Second, as the device is not seen angiographically, it is imperative that optical coherence tomography be performed to confirm LSD. When recognized and treated, the procedural and long-term outcomes are good for this complication.

Intravascular ultrasound to guide left main stem intervention: a NOBLE trial substudy

AIMS

We aimed to investigate the association between the use and findings of IVUS with clinical outcomes in the PCI arm of a randomised trial of LMS PCI.

METHODS AND RESULTS

The NOBLE trial randomised patients with LMS disease to treatment by PCI or CABG. Of 603 patients treated by PCI, 435 (72%) underwent post-PCI IVUS assessment, 224 of which were analysed in a core laboratory. At five years, the composite of MACCE was 18.9% if post-PCI IVUS was performed versus 25.0% if it was not performed (p=0.45, after adjustment). Overall repeat revascularisation was not reduced (10.6% vs 16.5%, p=0.11); however, LMS TLR was (5.1% vs 11.6%, p=0.01) if IVUS was used. For comparison of stent expansion, LMS MSA was split into tertiles. We found no significant difference in MACCE, death, myocardial infarction or stent thrombosis between tertiles. There was a significant difference between the lower and upper tertiles for repeat revascularisation (17.6% vs 5.2%, p=0.02) and LMS TLR (12.2% vs 0%, p=0.002).

CONCLUSIONS

Post-PCI IVUS assessment and adequate stent expansion are not associated with reduced MACCE; however, there is an association with reduced LMS TLR. The use of intracoronary imaging to prevent stent underexpansion in LMS PCI is likely to improve outcomes.

Erratum to: Common and Uncommon CTO complications

[This corrects the article DOI: 10.15420/icr.2018.10.2.].

A Technical Focus on Antegrade Dissection and Re-entry for Coronary Chronic Total Occlusions: a Practice Update for 2019

Coronary chronic total occlusions (CTOs) are a commonly encountered lesion. These present in a diverse patient population with variable anatomy. Technical success rates of ~90% are achievable for CTO lesions in centers with appropriate expertise. Many lesions can be crossed with wire-based techniques. However, the most anatomically complex and technically challenging lesions will often require more advanced approaches such as retrograde access and/or the application of blunt dissection techniques in the vessel to safely navigate long and/or ambiguous CTO segments. Retrograde dissection and re-entry (RDR) and antegrade dissection and re-entry (ADR) strategies are often needed to treat such lesions. In many circumstances, ADR offers a safe and efficient means to successfully cross a CTO lesion. Therefore, operators must remain cognizant of the risks and benefits of differing technical approaches during CTO percutaneous coronary intervention, particularly when both ADR and RDR are feasible. This article provides an overview of the ADR technique in addition to updated approaches in contemporary clinical practice.

Algorithmic solutions to common problems encountered during chronic total occlusion angioplasty: The algorithms within the algorithm

Improved technical equipment, dissemination of best practices, and the importance of complete coronary revascularization have led to a renewed interest in coronary chronic total occlusion (CTO) PCI. In particular, the hybrid algorithm has been associated with increasing procedural success rates in the US. However, the hybrid algorithm only covers overarching strategies in the overall approach to these lesions. Several technical challenges can occur during execution of these approaches, each of which has several potential solutions. A systematic or algorithmic approach to dealing with these challenges could contribute to improved procedural efficiency and higher procedural success. While there have been isolated attempts in the past to codify approaches to each of these situations, there has not been a contemporary, comprehensive review of the potential solutions to these problems. We present 10 common problems encountered during CTO PCI and a consensus hierarchical approach to them.

Recovery of myocardial perfusion after percutaneous coronary intervention of chronic total occlusions is comparable to hemodynamically significant non-occlusive lesions

Background

The benefits of chronic coronary total occlusion (CTO) percutaneous coronary intervention (PCI) are being questioned. The aim of this study was to assess the effects of CTO PCI on absolute myocardial perfusion, as compared with PCI of hemodynamically significant non‐CTO lesions.

Methods

Consecutive patients with a preserved left ventricular ejection fraction (≥50%) and a CTO or non‐CTO lesion, in whom [¹⁵O]H₂O positron emission tomography was performed prior and after successful PCI, were included. Change in quantitative (hyperemic) myocardial blood flow (MBF), coronary flow reserve (CFR) and perfusion defect size (in myocardial segments) were compared between CTOs and non‐CTO lesions.

Results

In total 92 patients with a CTO and 31 patients with a non‐CTO lesion were included. CTOs induced larger perfusion defect sizes (4.51 ± 1.69 vs. 3.23 ± 2.38 segments, P < 0.01) with lower hyperemic MBF (1.30 ± 0.37 vs. 1.58 ± 0.62 mL·min⁻¹·g⁻¹, P < 0.01) and similarly impaired CFR (1.66 ± 0.75 vs. 1.89 ± 0.77, P = 0.17) compared with non‐CTO lesions. After PCI both hyperemic MBF and CFR increased similarly between groups (P = 0.57 and 0.35) to normal ranges with higher hyperemic MBF values in non‐CTO compared with CTO (2.89 ± 0.94 vs. 2.48 ± 0.73 mL·min⁻¹·g⁻¹, P = 0.03). Perfusion defect sizes decreased similarly after CTO PCI and non‐CTO PCI (P = 0.14), leading to small residual defect sizes in both groups (1.15 ± 1.44 vs. 0.61 ± 1.45 segments, P = 0.054).

Conclusions

Myocardial perfusion findings are slightly more hampered in patients with a CTO before and after PCI. Percutaneous revascularization of CTOs, however, improves absolute myocardial perfusion similarly to PCI of hemodynamically significant non‐CTO lesions, leading to satisfying results.

One-Year Clinical Outcomes of the Hybrid CTO Revascularization Strategy After Hospital Discharge: A Subanalysis of the Multicenter RECHARGE Registry

OBJECTIVES

Percutaneous coronary intervention (PCI) of chronic total occlusion (CTO) has historically been associated with higher event rates during follow-up. The hybrid algorithm and contemporary wiring and dissection re-entry (DR) techniques can potentially improve long-term outcomes after CTO-PCI. This study assessed the long-term clinical outcomes of the hybrid CTO practice, when applied by operators with varying experience levels.

METHODS

We examined the 1-year clinical events after hospital discharge of the RECHARGE population, according to technical outcome and final technique. The primary endpoint was major adverse cardiac event (MACE) rate. Centers that provided ≥90% complete 12-month follow-up were included.

RESULTS

Follow-up data of 1067 out of 1165 patients (92%) were provided by 13 centers. Mean follow-up duration was 362.8 ± 0.9 days. One-year MACE-free survival rate was 91.3% (974/1067). MACE included death (1.9%; n = 20), myocardial infarction (1.4%; n = 15), target-vessel failure (5.9%; n = 63), and target-vessel revascularization (TVR) (5.5%; n = 59). Non-TVR was performed in 6.7% (n = 71). MACE was significantly in favor of successful CTO-PCI (8.0% vs 13%; P=.04), even after adjusting for baseline differences (adjusted hazard ratio, 0.59; 95% confidence interval, 0.36-0.98; P=.04). Other events, including individual MACE components, were comparable with respect to technical outcome and final technique (DR vs non-DR techniques).

CONCLUSIONS

The use of the hybrid algorithm with contemporary techniques by moderate to highly experienced operators for CTO-PCI is safe and associated with a low 1-year event rate. Successful procedures are associated with a better MACE rate. DR techniques can be used as first-line strategies alongside intimal wiring techniques without compromising clinical outcomes.

Common and Uncommon CTO Complications

Despite the ongoing development of technical skills, increasing operator experience and improvements in medical devices, percutaneous coronary interventions (PCI) for chronic total occlusions (CTO) are still the most challenging procedures in interventional cardiology for coronary artery disease. Due to the complexity of the procedures, there is an increased complication rate compared with PCIs for the treatment of non-occlusive disease. This may significantly increase procedural morbidity and potentially mortality. CTO-PCI related complications include all the usual complications that are seen in routine PCI in addition to unique issues such as inadvertent occlusion of donor vessels or injury of collateral channels causing haemodynamic instability or ischaemia. To minimise the morbidity associated with these procedures, it is important to be aware of potential complications and recognise them in a timely fashion. Should they arise, operators should be able to deal with them in a safe and efficient manner.

Fully Transradial Versus Transfemoral Approach for Percutaneous Intervention of Coronary Chronic Total Occlusions Applying the Hybrid Algorithm

Background—

Small observational studies demonstrate the feasibility of transradial approach for chronic total occlusion (CTO) percutaneous coronary intervention. The aim of the current study is to assess technical success, complication rates, and procedural efficiency in fully transradial approach (fTRA) and transfemoral approach (TFA) in a large prospective European registry adopting the hybrid algorithm for CTO percutaneous coronary intervention (Registry of CrossBoss and Hybrid Procedures in France, the Netherlands, Belgium and United Kingdom, RECHARGE registry).

Methods and Results—

We analyzed 1253 CTO percutaneous coronary intervention procedures performed according to the hybrid protocol in 17 European centers, comparing fTRA (single or biradial access) and TFA (single or bifemoral or combined radial and femoral access). fTRA was applied in 306 (24%) and TFA in 947 (76%) cases. The average Japanese CTO score was 2.1±1.2 in fTRA and 2.3±1.1 in TFA ( P =0.06). Technical success was achieved in 85% in fTRA and 86% in TFA ( P =0.51). Technical success was comparable for fTRA and TFA in different Japanese CTO score subgroups after multivariable analysis and after propensity adjustment. In-hospital major adverse cardiac and cerebral events occurred in 2.0% in fTRA and 2.9% in TFA ( P =0.40). Major access site bleeding occurred in 0.3% in fTRA and 0.5% in TFA ( P =0.66). fTRA compared with TFA had similar procedural duration (80 minutes [54–120 minutes] versus 90 minutes [60–121 minutes]; P =0.07), similar radiation dose (dose area product 89 Gray×cm 2 [52–163 Gray×cm 2 ] versus 101 Gray×cm 2 [59–171 Gray×cm 2 ]; P =0.06), and lower contrast agent use (200 mL [150–310 mL] versus 250 mL [200–350 mL]; P <0.01).

Conclusions—

fTRA CTO percutaneous coronary intervention is a valid alternative to TFA with a high rate of success, low complication rates, and no decrease in procedural efficiency.

Antegrade Dissection and Reentry as Part of the Hybrid Chronic Total Occlusion Revascularization Strategy

Background—

Development of the CrossBoss and Stingray devices for antegrade dissection and reentry (ADR) of chronic total occlusions has improved historically suboptimal outcomes. However, the outcomes, safety, and failure modes of the technique have to be studied in a larger patient cohort. This preplanned substudy of the RECHARGE registry (Registry of CrossBoss and Hybrid Procedures in France, the Netherlands, Belgium and United Kingdom) aims to evaluate the value and use of ADR and determine its future position in contemporary chronic total occlusion intervention.

Methods and Results—

Patients were selected if an ADR strategy was applied. Outcomes, safety, and failure modes of the technique were assessed. The ADR technique was used in 23% (n=292/1253) of the RECHARGE registry and was mainly applied for complex lesions (Japanese chronic total occlusion score=2.7±1.1). ADR was the primary strategy in 30% (n=88/292), of which 67% were successful. Bail-out ADR strategies were successful in 63% (n=133/210). The Controlled ADR (ie, combined CrossBoss-Stingray) subtype was applied most frequently (32%; n=93/292) and successfully (81%; n=75/93). Overall per-lesion success rate was 78% (n=229/292), after use of additional bail-out strategies. The inability to reach the distal target zone (n=48/100) or to reenter (n=43/100) most commonly led to failure. ADR-associated major events occurred in 3.4% (n=10/292).

Conclusions—

Although mostly applied as a bail-out strategy for complex lesions, the frequency, outcomes, and low complication rate of the ADR technique and its subtypes confirm the benefit and value of the technique in hybrid chronic total occlusion percutaneous coronary intervention, especially when antegrade wiring or retrograde approaches are not feasible.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT02075372.

One-year outcomes after successful chronic total occlusion percutaneous coronary intervention: The impact of dissection re-entry techniques

We aimed to determine clinical outcomes 1 year after successful chronic total occlusion (CTO) PCI and, in particular, whether use of dissection and re-entry strategies affects clinical outcomes. Hybrid approaches have increased the procedural success of CTO percutaneous coronary intervention (PCI) but longer-term outcomes are unknown, particularly in relation to dissection and re-entry techniques. Data were collected for consecutive CTO PCIs performed by hybrid-trained operators from 7 United Kingdom (UK) centres between 2012 and 2014. The primary endpoint (death, myocardial infarction, unplanned target vessel revascularization) was measured at 12 months along with angina status. One-year follow up data were available for 96% of successful cases (n = 805). In total, 85% of patients had a CCS angina class of 2-4 prior to CTO PCI. Final successful procedural strategy was antegrade wire escalation 48%; antegrade dissection and re-entry (ADR) 21%; retrograde wire escalation 5%; retrograde dissection and re-entry (RDR) 26%. Overall, 47% of CTOs were recanalized using dissection and re-entry strategies. During a mean follow up of 11.5 ± 3.8 months, the primary endpoint occurred in 8.6% (n = 69) of patients (10.3% (n = 39/375) in DART group and 7.0% (n = 30/430) in wire-based cases). The majority of patients (88%) had no or minimal angina (CCS class 0 or 1). ADR and RDR were used more frequently in more complex cases with greater disease burden, however, the only independent predictor of the primary endpoint was lesion length. CTO PCI in complex lesions using the hybrid approach is safe, effective and has a low one-year adverse event rate. The method used to recanalize arteries was not associated with adverse outcomes. © 2017 Wiley Periodicals, Inc.

The first clinical experience with a novel "locking" microcatheter in chronic coronary total occlusions

AIMS

A novel "locking" microcatheter has been developed to address residual failure modes in chronic total occlusion (CTO) percutaneous coronary intervention (PCI). The aim of this study was to report the first clinical experience of this device.

METHODS AND RESULTS

The microcatheter was assessed prospectively in 92 unselected CTO cases across six European sites. Overall technical success was 85.9% (79/92) and 97.5% for patients with a J-CTO score of <3 (39/40). Within-CTO tortuosity was the only lesion characteristic to predict reduced technical success (OR 0.10 [0.01-0.97], p=0.047). Calcification (OR 0.45 [0.04-5.31], p=0.53), lesion length >20 mm (OR 0.58 [0.05-6.81], p=0.66) and a blunt proximal cap (OR 0.47 [0.08-2.90], p=0.42) were not associated with technical failure in this case series. Locking facilitated guidewire crossing (after initial failure) of the proximal cap in 23 cases, distal cap in 11 cases and CTO body in 10 cases, and delivery of the microcatheter through to the distal vessel in 22 cases. The overall procedural complication rate was 1.1% (1/92) with no major events.

CONCLUSIONS

Guidewire locking with this novel microcatheter assists penetration and crossing of fibrocalcific anatomy with a high degree of safety. Using this device in CTO PCI may lead to improved primary wiring and overall procedural success rates.

Initial Experience of Bioabsorbable Polymer Everolimus-Eluting Synergy Stents in High-Risk Patients Undergoing Complex Percutaneous Coronary Intervention With Early Discontinuation of Dual-Antiplatelet Therapy

AIMS

As more elderly and co-morbid patients require percutaneous revascularization, 1 year of dual-antiplatelet therapy (DAPT) becomes concerning. Synergy stents (Boston Scientific) allow for early cessation of DAPT. This study assessed those in our unit who underwent percutaneous coronary intervention (PCI) with a Synergy stent to examine a minimum of 6 months of clinical outcomes after early discontinuation of DAPT.

METHODS AND RESULTS

All non-trial patients in our unit who had PCI with a Synergy stent from August 2013 to February 2016 were retrospectively analyzed. Follow-up was by medical record review or direct contact for postprocedural complications or adverse events. In total, 185 patients underwent PCI with a Synergy stent over 1 year prior. The mean patient age was 72.0 ± 11.0 years (range, 41-97 years). Stenting involved left main stem (14.1%), multivessel disease (33.0%), and chronic total occlusion (33.0%). DAPT discontinuation occurred in 78.4% by 3 months with no stent thrombosis. Three patients required target-vessel revascularization (TVR) by 1 year. There were no cardiac deaths or myocardial infarctions. Twenty-five patients were able to have non-cardiac procedures within the study period.

CONCLUSION

The use of the Synergy everolimus-eluting stent allows for early discontinuation of DAPT, reducing risk of bleeding complications and facilitating non-cardiac procedures, without an increase in stent thrombosis and with excellent results for TVR.

Percutaneous coronary angioplasty versus coronary artery bypass grafting in treatment of unprotected left main stenosis (NOBLE): a prospective, randomised, open-label, non-inferiority trial

BACKGROUND

Coronary artery bypass grafting (CABG) is the standard treatment for revascularisation in patients with left main coronary artery disease, but use of percutaneous coronary intervention (PCI) for this indication is increasing. We aimed to compare PCI and CABG for treatment of left main coronary artery disease.

METHODS

In this prospective, randomised, open-label, non-inferiority trial, patients with left main coronary artery disease were enrolled in 36 centres in northern Europe and randomised 1:1 to treatment with PCI or CABG. Eligible patients had stable angina pectoris, unstable angina pectoris, or non-ST-elevation myocardial infarction. Exclusion criteria were ST-elevation myocardial infarction within 24 h, being considered too high risk for CABG or PCI, or expected survival of less than 1 year. The primary endpoint was major adverse cardiac or cerebrovascular events (MACCE), a composite of all-cause mortality, non-procedural myocardial infarction, any repeat coronary revascularisation, and stroke. Non-inferiority of PCI to CABG required the lower end of the 95% CI not to exceed a hazard ratio (HR) of 1·35 after up to 5 years of follow-up. The intention-to-treat principle was used in the analysis if not specified otherwise. This trial is registered with ClinicalTrials.gov identifier, number NCT01496651.

FINDINGS

Between Dec 9, 2008, and Jan 21, 2015, 1201 patients were randomly assigned, 598 to PCI and 603 to CABG, and 592 in each group entered analysis by intention to treat. Kaplan-Meier 5 year estimates of MACCE were 29% for PCI (121 events) and 19% for CABG (81 events), HR 1·48 (95% CI 1·11-1·96), exceeding the limit for non-inferiority, and CABG was significantly better than PCI (p=0·0066). As-treated estimates were 28% versus 19% (1·55, 1·18-2·04, p=0·0015). Comparing PCI with CABG, 5 year estimates were 12% versus 9% (1·07, 0·67-1·72, p=0·77) for all-cause mortality, 7% versus 2% (2·88, 1·40-5·90, p=0·0040) for non-procedural myocardial infarction, 16% versus 10% (1·50, 1·04-2·17, p=0·032) for any revascularisation, and 5% versus 2% (2·25, 0·93-5·48, p=0·073) for stroke.

INTERPRETATION

The findings of this study suggest that CABG might be better than PCI for treatment of left main stem coronary artery disease.

FUNDING

Biosensors, Aarhus University Hospital, and participating sites.

The collateral circulation of coronary chronic total occlusions

AIMS

Despite advances in understanding the physiological role of collaterals in coronary chronic total occlusions (CTOs), collateral anatomy remains poorly defined. Our aim was to define the anatomy and interventional utility of collaterals within a large population of patients with CTOs.

METHODS AND RESULTS

We studied the coronary angiograms of 481 patients with 519 CTOs at six centres in the U.K. over four years. Detailed angiographic analysis was performed by interventional cardiologists specialising in CTO percutaneous coronary intervention (PCI). All visible collaterals with a collateral connection (CC) grade ≥1 were recorded. A subgroup of CTOs (n=277) was assessed for interventional capability, defined as whether the collateral supply was able to facilitate retrograde access. We described 45 different collateral patterns: 20 in right coronary artery (RCA), 13 in left anterior descending (LAD), and 12 in circumflex artery CTOs. Septal collaterals from the LAD to the right posterior descending artery (RPDA), and from the posterior descending artery to the LAD were most common, and most often considered as having "interventional capability".

CONCLUSIONS

This is the largest analysis of collateral circulation anatomy in a population of patients with CTOs. We anticipate that these data will be of significant benefit in angiographic analysis and procedure planning for CTO PCI.

Did the use of the Guideliner V2(TM) guide catheter extension increase complications? A review of the incidence of complications related to the use of the V2 catheter, the influence of right brachiocephalic arterial anatomy and the redesign of the V3(TM) Guideliner and clinical outcomes

Objective

We sought to investigate the incidence of complications associated with V2 Guideliner, understand the mechanisms and evaluate the impact of alterations made to the V3 Guideliner.

Methods

Retrospective analysis of consecutive cases employing V2 Guideliner from two university teaching hospitals. Complications were identified, analysed and classified into major versus minor ones. To understand the potential anatomical mechanism of these complications, analysis of normal great vessel anatomy was undertaken in separate cohort of patients undergoing cardiac catheterisation via right radial approach. Further analysis of consecutive cases employing V3 Gudieliner took place and the incidence of complications were compared between V2 and V3 groups.

Results

Total of 188 cases of V2 Guideliner use were identified. One major complication was reported (coronary dissection). Proximal collar interaction and stent damage occurred in 19 cases (10%). Anatomical data suggest that extending the V2 Guideliner tubing sited the proximal collar of the device in the brachiocephalic/subclavian artery, a potential site of tortuosity and potential cause of the Guideliner proximal collar-stent interaction. Further analysis of 124 cases of V3 Guideliner use demonstrated no cases with proximal collar-stent interactions, one case of longitudinal stent deformation and two incidents of stent interaction with the distal edge of the V3 Guideliner.

Conclusions

We have demonstrated a higher incidence of V2 Guideliner complications compared to previous series. The change in design of the V2 Guideliner was a likely contributor but the modifications with V3 Guideliner appear to have ameliorated this issue.

Impact of proctoring on success rates for percutaneous revascularisation of coronary chronic total occlusions

OBJECTIVE

To assess the impact of proctoring for chronic total occlusion (CTO) percutaneous coronary intervention (PCI) in six UK centres.

METHODS

We retrospectively analysed 587 CTO procedures from six UK centres and compared success rates of operators who had received proctorship with success rates of the same operators before proctorship (pre-proctored) and operators in the same institutions who had not been proctored (non-proctored). There were 232 patients in the pre-proctored/non-proctored group and 355 patients in the post-proctored group. Complexity was assessed by calculating the Japanese CTO (JCTO) score for each case.

RESULTS

CTO PCI success was greater in the post-proctored compared with the pre-proctored/non-proctored group (77.5% vs 62.1%, p<0.0001). In more complex cases where JCTO≥2, the difference in success was greater (70.7% vs 49.5%, p=0.0003). After proctoring, there was an increase in CTO PCI activity in centres from 2.5% to 3.5%, p<0.0001 (as a proportion of total PCI), and the proportion of very difficult cases with JCTO score ≥3 increased from 15.3% (35/229) to 29.7% (105/354), p<0.0001.

CONCLUSIONS

Proctoring resulted in an increase in procedural success for CTO PCI, an increase in complex CTO PCI and an increase in total CTO PCI activity. Proctoring may be a valuable way to improve access to CTO PCI and the likelihood of procedural success.

Subintimal TRAnscatheter Withdrawal (STRAW) of hematomas compressing the distal true lumen: a novel technique to facilitate distal reentry during recanalization of chronic total occlusion (CTO)

The development of a large hematoma impairing visualization of the distal true lumen is a recognized complication of antegrade recanalization of chronic total occlusions, often forcing the operator to abort the procedure or switch to a retrograde approach. We describe a novel technique utilizing an over-the-wire balloon inflated in the proximal occluded vessel to block inflow and allow aspiration of the blood from the subintimal space. This decompressed the true lumen, restored distal visualization, and allowed successful reentry using a dedicated technology. Utilization of this novel technique may rescue antegrade recanalization attempts complicated by large subintimal hematomas.

Efficacy of the RADPAD protective drape during real world complex percutaneous coronary intervention procedures

The RADPAD is a lead-free surgical drape containing bismuth and barium that has been demonstrated to reduce scatter radiation exposure to primary operators during fluoroscopic procedures. It is not known to what degree the RADPAD reduces radiation exposure in operators who perform highly complex percutaneous coronary intervention (PCI) requiring prolonged fluoroscopic screening times. Sixty consecutive patients due to undergo elective complex PCI involving rotational atherectomy, multivessel PCI, or chronic total occlusions were randomized in a 1:1 pattern to have their procedures performed with and without the RADPAD drape in situ. Dosimetry was performed on the left arm of the primary operator. There were 40 cases of chronic total occlusion, including 28 with contralateral injections; 15 cases involving rotational atherectomy; and 5 cases of multivessel PCI. There was no significant difference in screening times or dose-area products between the 2 patient groups. Primary operator radiation dose relative to screening time (RADPAD: slope = 1.44, R² = 0.25; no RADPAD: slope = 4.60, R² = 0.26; analysis of covariance F = 4.81, p = 0.032) and dose-area product (RADPAD: slope = 0.003, R² = 0.26; no RADPAD: slope = 0.011, R² = 0.52; analysis of covariance F = 12.54, p = 0.008) was significantly smaller in the RADPAD cohort compared to the no-RADPAD group. In conclusion, the RADPAD significantly reduces radiation exposure to primary operators during prolonged, complex PCI cases.

Clinical Impact of Stent Design

The introduction and widespread adoption of drug-eluting stents into routine clinical practice has seen tremendous changes in the practice of interventional cardiology. For a prolonged period, manufacturers have focused research on drugs and polymers that are the key to the prevention of in-stent restenosis. However, stent platform design and its clinical implications have now come back to the fore. This has occurred for numerous reasons, but has primarily been driven by the need for modern stents to perform well in increasingly demanding clinical scenarios. This paper reviews the historical evolution of stent platform design. Current manufacturing processes and materials are also explored. Geometric stent construction and its implications for longitudinal stability and the longer term risks of stent fracture are reviewed. Finally, the implications of the specific stent chosen for different clinical applications including the treatment of bifurcations and left main disease are also summarised. This article will familiarise cardiologists with the crucial impact of each of these factors on modern day practice, as well as acute and long-term outcomes for patients.

Clinical Impact of Stent Design

The introduction and widespread adoption of drug-eluting stents into routine clinical practice has seen tremendous changes in the practice of interventional cardiology. For a prolonged period, manufacturers have focused research on drugs and polymers that are the key to the prevention of in-stent restenosis. However, stent platform design and its clinical implications have now come back to the fore. This has occurred for numerous reasons, but has primarily been driven by the need for modern stents to perform well in increasingly demanding clinical scenarios. This paper reviews the historical evolution of stent platform design. Current manufacturing processes and materials are also explored. Geometric stent construction and its implications for longitudinal stability and the longer term risks of stent fracture are reviewed. Finally, the implications of the specific stent chosen for different clinical applications including the treatment of bifurcations and left main disease are also summarised. This article will familiarise cardiologists with the crucial impact of each of these factors on modern day practice, as well as acute and long-term outcomes for patients.

Probucol [4,4′-[(1-Methylethylidene)bis(thio)]bis-[2,6-bis(1,1-dimethylethyl)phenol]] Inhibits Compensatory Remodeling and Promotes Lumen Loss Associated with Atherosclerosis in Apolipoprotein E-Deficient Mice

Probucol [4,4'-[(1-methylethylidene)bis(thio)]bis-[2,6-bis(1,1-dimethylethyl)phenol]] was withdrawn from the United States market because it failed to inhibit atherosclerosis in human femoral arteries, yet the drug was shown subsequently to inhibit atherosclerosis in human carotid arteries, and probucol monosuccinate ester is presently being tested in a phase III clinical trial as an antiatherosclerotic compound based on its anti-inflammatory properties. Inflammatory macrophages are implicated in arterial remodeling associated with atherosclerosis, and probucol inhibits experimental atherosclerosis in part by decreasing macrophages in lesions. However, the impact of probucol on remodeling is unknown, although such knowledge could help explain why the drug's benefit on human atherosclerosis is controversial. We therefore examined the effect of probucol on remodeling of the common carotid artery in apolipoprotein E-deficient mice. We observed that during de novo atherosclerosis, plaque growth was fully compensated by expansive remodeling, such that lumen area was unaffected. Early lesions were composed almost entirely of macrophages, and their contribution to lesion area progressively decreased thereafter. Probucol significantly decreased plaque area, expression of vascular cell adhesion molecule-1, and proliferation of intimal cells, resulting in delayed macrophage accumulation in the vessel. Probucol also decreased the production and activity of matrix metalloproteinases-2 and -9, independent of the plasmin protease system, and this was associated with an inhibition of expansive remodeling, resulting in lumen loss. These studies show that probucol attenuates compensatory remodeling associated with de novo atherosclerosis, probably via its anti-inflammatory properties. Our findings suggest that lumen volume is not a suitable surrogate to assess the antiatherosclerotic activity of probucol and related drugs.

Impaired endothelium-dependent and -independent vasodilation in elderly patients with chronic heart failure

BACKGROUND

Impaired endothelium-dependent and independent vasodilator responses in chronic heart failure (CHF) have been well described. Previous studies involved younger patients and omitted medications prior to study.

AIMS

We explored if new therapeutic interventions would restore vasodilator responses in typical patients with chronic heart failure.

METHODS AND RESULTS

24 patients and 15 controls were recruited, patients were maintained on their usual medications. Forearm blood flow responses were measured by venous occlusion plethysmography in response to incremental doses of sodium nitroprusside (SNP) (6, 9 and 12 nmol/min), acetylcholine (ACH) (120, 180 and 240 nmol/min), angiotensin II (AII) (1, 10 and 100 nmol/min) and N(g)-Nitro-L-arginine methyl ester (L-NAME) (1, 2 and 4 nmol/min) infused into the non-dominant brachial artery. FBF responses to SNP were impaired in patients compared with controls (13.7(9.9,17.4) vs. 24.8(18.6,30.9)) arbitrary units, P<0.001). Similarly FBF responses to ACH were reduced in patients compared with controls (7.5(4.2,10.9) vs. 24.8(16.4,33.2)) arbitrary units, P<0.001. Decreased FBF was noted in response to AII and L-NAME but was significant only for AII and did not differ between groups.

CONCLUSIONS

In elderly patients with CHF, endothelium-dependent and independent vasodilator responses were blunted compared with controls. Defects in nitric oxide bioavailability and smooth muscle responsiveness are not reversed by modern medical management of the heart failure syndrome.

Effects of dietary omega-3 fatty acid supplementation on endothelium-dependent vasodilation in patients with chronic heart failure

We investigated the effects of omega-3 fatty acids administration on endothelium-dependent vasodilation in patients > or =65 years old who received treatment for chronic heart failure (CHF). Twenty patients (mean age 73 years; 15 men) with grade II and III CHF who were on maximal medical management were recruited. Patients were randomized in a double-blind, crossover fashion to 6 weeks of omega-3 fatty acid (1.8 g ecosapentaenoic acid and 1.2 g docosahexaenoic acid) or olive oil. Forearm blood flow (FBF) responses to incremental doses of intra-arterial sodium nitroprusside, acetycholine (ACH), angiotensin-II, and N(g)-nitro-L-arginine methyl ester were assessed by venous occlusion strain gauge plethysmography. The endothelium-dependent increase in FBF was greater in response in ACH infusion after omega-3 fatty acid administration (7.9, 95% confidence interval [CI] 4.81 to 11.08 to 11.3, 95% CI 7.31 to 15.23 arbitrary units (p <0.05) compared with baseline (7.95, 95% CI 4.8 to 11.08 arbitrary units) and olive oil administration (7.27, 95% CI 4.66 to 9.88 arbitrary units) (p = NS for both). Neither omega-3 fatty acid nor olive oil altered endothelium-independent vasodilation in response to infusion of sodium nitroprusside, nor did they influence vasoconstrictor responses to angiotensin-II or N(g)-nitro-L-arginine methyl ester. Dietary omega-3 fatty acid supplementation was accompanied by an increase in FBF response to ACH, which represents enhanced endothelium-dependent vasodilation in CHF. Further studies are warranted to assess the mechanism responsible for the beneficial actions of omega-3 fatty acids in CHF.

Low flow promotes instent intimal hyperplasia. Comparison with lumen loss in balloon-injured and uninjured vessels and the effects of the antioxidant pyrrolidine dithiocarbamate

Low flow (LF) promotes late lumen loss after angioplasty by exacerbating inward remodelling through redox-sensitive mechanisms. Stents eliminate inward remodelling and the effect of LF on in-stent restenosis is uncertain. We performed over-sized (1.3-1.5:1) stenting (S) and balloon injury (in the same vessel, B) to the carotid arteries of cholesterol-fed rabbits and compared 28-day late lumen loss with that in an uninjured segment in the same vessel (U). Vessels (n = 5 animals per group) were subjected to high (H), normal (N) and low (L) flow in animals fed either vehicle (V) or the antioxidant pyrrolidine dithiocarbamate, PDTC (P). LF significantly increased in-stent neointima formation relative to normal and high flow (SLV 0.72 +/- 0.07 mm(2) versus SNV 0.43 +/- 0.08 mm(2) versus SHV 0.28 +/- 0.04 mm(2), P < 0.05). However, LF resulted in greater lumen loss in segments from the same vessel subject to balloon injury (lumen SLV 5.18 +/- 0.40 mm(2) and SNV 5.32 +/- 0.40 mm(2) versus BLV 1.28 +/- 0.33 mm(2) and BNV 2.19 +/- 0.28 mm(2)), by greater enhancement of inward remodelling. In addition, inward remodelling and lumen loss due to LF were greater in balloon-injured segments than in adjacent uninjured segments where shear homeostatic remodelling occurs (lumen BLV 1.28 +/- 0.33 mm(2) versus ULV 1.52 +/- 0.22 mm(2)). Lastly, while PDTC effectively reduced intima formation and inward remodelling due to LF in balloon-injured vessels there was no effect on flow-dependent neointima formation in stented vessels. We conclude that LF accentuates in-stent neointima formation, but that flow-dependent lumen loss after stenting is less than that after balloon injury. When LF is present lumen loss can be minimised by antioxidants or stenting.