Coronary sinus reducer for the treatment of refractory angina (ORBITA-COSMIC): a randomised, placebo-controlled trial.

BACKGROUND: The coronary sinus reducer (CSR) is proposed to reduce angina in patients with stable coronary artery disease by improving myocardial perfusion. We aimed to measure its efficacy, compared with placebo, on myocardial ischaemia reduction and symptom improvement. METHODS: ORBITA-COSMIC was a double-blind, randomised, placebo-controlled trial conducted at six UK hospitals. Patients aged 18 years or older with angina, stable coronary artery disease, ischaemia, and no further options for treatment were eligible. All patients completed a quantitative adenosine-stress perfusion cardiac magnetic resonance scan, symptom and quality-of-life questionnaires, and a treadmill exercise test before entering a 2-week symptom assessment phase, in which patients reported their angina symptoms using a smartphone application (ORBITA-app). Patients were randomly assigned (1:1) to receive either CSR or placebo. Both participants and investigators were masked to study assignment. After the CSR implantation or placebo procedure, patients entered a 6-month blinded follow-up phase in which they reported their daily symptoms in the ORBITA-app. At 6 months, all assessments were repeated. The primary outcome was myocardial blood flow in segments designated ischaemic at enrolment during the adenosine-stress perfusion cardiac magnetic resonance scan. The primary symptom outcome was the number of daily angina episodes. Analysis was done by intention-to-treat and followed Bayesian methodology. The study is registered with ClinicalTrials.gov, NCT04892537, and completed. FINDINGS: Between May 26, 2021, and June 28, 2023, 61 patients were enrolled, of whom 51 (44 [86%] male; seven [14%] female) were randomly assigned to either the CSR group (n=25) or the placebo group (n=26). Of these, 50 patients were included in the intention-to-treat analysis (24 in the CSR group and 26 in the placebo group). 454 (57%) of 800 imaged cardiac segments were ischaemic at enrolment, with a median stress myocardial blood flow of 1·08 mL/min per g (IQR 0·77-1·41). Myocardial blood flow in ischaemic segments did not improve with CSR compared with placebo (difference 0·06 mL/min per g [95% CrI -0·09 to 0·20]; Pr(Benefit)=78·8%). The number of daily angina episodes was reduced with CSR compared with placebo (OR 1·40 [95% CrI 1·08 to 1·83]; Pr(Benefit)=99·4%). There were two CSR embolisation events in the CSR group, and no acute coronary syndrome events or deaths in either group. INTERPRETATION: ORBITA-COSMIC found no evidence that the CSR improved transmural myocardial perfusion, but the CSR did improve angina compared with placebo. These findings provide evidence for the use of CSR as a further antianginal option for patients with stable coronary artery disease. FUNDING: Medical Research Council, Imperial College Healthcare Charity, National Institute for Health and Care Research Imperial Biomedical Research Centre, St Mary's Coronary Flow Trust, British Heart Foundation.

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.

Factors Influencing Stent Failure in Chronic Total Occlusion Coronary Intervention.

Stent failure remains one of the greatest challenges for interventional cardiologists. Despite the evolution to superior second- and third-generation drug-eluting stent designs, increasing use of intracoronary imaging and the adoption of more potent antiplatelet regimens, registries continue to demonstrate a prevalence of stent failure or target lesion revascularisation of 15-20%. Predisposition to stent failure is consistent across both chronic total occlusion (CTO) and non-CTO populations and includes patient-, lesion- and procedure-related factors. However, histological and pathophysiological properties specific to CTOs, alongside complex strategies to treat these lesions, may potentially render percutaneous coronary interventions in this cohort more vulnerable to failure. Prevention requires recognition and mitigation of the precipitants of stent failure, optimisation of interventional techniques, including image-guided precision percutaneous coronary intervention, and aggressive modification of a patient's cardiovascular risk factors. Management of stent failure in the CTO population is technically challenging and itself begets recurrence. We aim to provide a comprehensive review of factors influencing stent failure in the CTO population and strategies to attenuate these.

The Impact of Calcium on Chronic Total Occlusion Management.

Coronary artery calcification is prevalent in chronic total occlusions (CTO), particularly in those of longer duration and post-coronary artery bypass. The presence of calcium predicts lower procedural success rates and a higher risk of complications of CTO percutaneous coronary intervention. Adjunctive imaging, including pre-procedural computed tomography and intracoronary imaging, are useful to understand the distribution and morphology of the calcium. Specialised guidewires and microcatheters, as well as penetration, subintimal entry and luminal re-entry techniques, are required to cross calcific CTOs. The use of both atherectomy devices and balloon-based calcium modification tools has been reported during CTO percutaneous coronary intervention, although they are limited by concerns regarding safety and efficacy in the subintimal space.

Initial Experiences of Percutaneous Coronary Intervention Using a New-Generation Everolimus-Eluting Stent Platform.

BACKGROUND: Outcomes from the new Synergy Megatron drug-eluting stent (DES) platform (Boston Scientific) are not yet reported. This study sought to evaluate periprocedural outcomes in patients undergoing percutaneous coronary intervention (PCI) using this technology. METHODS: This was a retrospective study across two United Kingdom centers of 139 patients undergoing PCI of 146 coronary lesions using the Synergy Megatron DES. The primary endpoint was the rate of cardiovascular death. The secondary endpoint was the rate of a composite of non-fatal myocardial infarction, target-vessel revascularization, in-stent restenosis, and probable/definite stent thrombosis. Available intravascular ultrasound (IVUS) imaging was reviewed post hoc and evaluated according to predefined IVUS optimization criteria. RESULTS: Mean follow-up duration was 137.3 ± 38.3 days. The primary endpoint occurred in 0.7% of patients and the secondary endpoint occurred in 0.0% of patients. There were no cases of longitudinal stent deformation (LSD); in patients undergoing an IVUS-guided procedure, our criteria for successful IVUS optimization was achieved in 74.1% of left main stem (LMS) and 83.3% of right coronary artery (RCA) lesions. Mean minimal stent area (MSA) was 14.5 ± 3.4 mm² in the LMS, 10.0 ± 2.5 mm² in the left anterior descending coronary artery, 9.8 ± 3.0 mm² in the left circumflex, and 12.2 ± 4.0 mm² in the RCA. CONCLUSION: This study demonstrated very low rates of short-term major adverse cardiovascular events with no cases of LSD or acute/subacute stent thrombosis. It highlights the overexpansion capabilities of the Synergy Megatron DES platform. The technology safely and effectively facilitates IVUS-optimized stent parameters for the treatment of large proximal vessels and bifurcations.

Intravascular Lithotripsy for Calcium Modification in Chronic Total Occlusion Percutaneous Coronary Intervention.

Intravascular lithotripsy (IVL) has been shown to be safe and effective for calcium modification in nonocclusive coronary artery disease (CAD), but there are only case reports of its use in calcified chronic total occlusions (CTO). We report data from an international multicenter registry of IVL use during CTO percutaneous coronary intervention (PCI) and provide provisional data regarding its efficacy and safety. During the study period, IVL was used in 55 of 1053 (5.2%) CTO PCI procedures. IVL was used within the occluded segment after successful CTO crossing in 53 procedures and during incomplete CTO crossing in 2 cases. The mean J-CTO score was 3.1. CTO PCI technical and procedural success was achieved in 53 (96%) and 51 (93%) cases. Six patients had a procedural complication, with 3 main vessel perforations (5%). Two had covered stent implantation, one required pericardiocentesis, and one was managed conservatively. All had combination therapy with another calcium modification device. Two patients had a procedural myocardial infarction (PMI) (4%), and two others had a major adverse cardiovascular event (MACE) (4%) at a median follow-up of 13 (4-21) months. IVL can effectively facilitate calcium modification during CTO PCI. More data are required to establish the efficacy and safety of IVL and other calcium modification devices when used extraplaque or in combination during CTO PCI.

Reverse longitudinal stent deformation during percutaneous intervention via the retrograde approach to a chronic total occlusion of the right coronary artery: a case report.

BACKGROUND: Longitudinal stent deformation (LSD) is an uncommon but recognized mechanical complication of coronary stent implantation, usually occurring at the proximal stent edge due to compression by guide catheter or catheter extensions. Retrograde techniques for chronic total occlusion (CTO) percutaneous coronary intervention expose the distal stent edge to potential interaction with retrograde equipment under a tensioned system. CASE SUMMARY: We describe a case of distal stent edge LSD, occurring during a retrograde approach to a right coronary artery CTO via septal collateral channels. While removing the externalized wire, interaction with the retrograde microcatheter caused compression of the distal end of the newly implanted stents. DISCUSSION: This unusual complication highlights the reduced longitudinal strength of newer generation stent platforms and the risks of interaction between retrograde equipment and stents on an externalized wire.

Management of stent underexpansion using intravascular lithotripsy-Defining the utility of a novel device.

OBJECTIVES: This study aimed to present a case series of patient treated for stent underexpansion resistant to conventional treatment with intravascular lithotripsy (IVL). BACKGROUND: Stent underexpansion is a powerful predictor of long-term stent patency and correlates with unfavorable clinical outcomes. This case series demonstrates the utility of IVL in managing stent underexpansion resistant to conventional treatment. METHODS: We describe a case series of patients with stent underexpansion due to calcific coronary artery disease treated with IVL. Stent underexpansion was identified as an inability to adequately expand stents with conventional treatment. Only cases that failed to achieve adequate expansion with high-pressure noncompliant balloon inflation were included. RESULTS: Thirteen patients from six institutions have been included in this case series. The average age was 70.25 years with 76.9% of male patients. The average pre-IVL minimal stent area (MSA) was 2.71 mm2 , which improved to 6.44 mm2 post-IVL treatment, representing an average MSA gain of 238%. There were no procedural, peri-procedural, or 30-day major adverse cardiac and cerebrovascular event. CONCLUSION: This case series demonstrates that IVL is a feasible, safe alternative for the management of stent underexpansion due to calcific coronary disease.

Incidence of "shocktopics" and asynchronous cardiac pacing in patients undergoing coronary intravascular lithotripsy.

AIMS: Coronary intravascular lithotripsy (IVL) is a novel approach to vascular calcium modification that restores vessel compliance allowing effective lesion expansion. In this study we report the capacity for coronary IVL to precipitate ventricular ectopics ("shocktopics") and asynchronous cardiac pacing. METHODS AND RESULTS: This was a retrospective review of all cases of coronary IVL (n=54) undertaken in the Royal Victoria Hospital, Belfast, between September 2018 and March 2019. The indication for PCI was chronic stable angina in 46.1% (n=26), non-ST-elevation acute coronary syndrome (NSTEACS) in 33.3% (n=18) and ST-elevation myocardial infarction (STEMI) in 18.5% (n=10) of patients. The incidence of coronary IVL-provoked ventricular capture was 77.8% (n=42). Multivariable logistic regression analysis identified heart rate as the only independent predictor of an increased risk of IVL-induced ventricular capture. Patients with a heart rate <65 bpm prior to IVL were sixteen-fold more likely (OR 16.3 [2.4-110.8], p=0.004) to experience events compared to patients with a heart rate ≥65 bpm. "Shocktopic" beat morphology was largely uniform in each patient and appeared dependent on the target lesion location, in keeping with mechano-electric coupling through activation of local stretch-activated cardiomyocyte channels. No adverse clinical events occurred as a result of coronary IVL-induced capture. CONCLUSIONS: Coronary IVL with the Shockwave Medical system is associated with a high incidence of "shocktopics" and asynchronous cardiac pacing that is largely dependent on the resting heart rate. There have been no clinical events associated with this phenomenon, but further systematic evaluation is warranted.

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.

Transcatheter aortic valve implantation: a new standard of care.

Aortic stenosis is the most common valvular lesion requiring intervention and with an ageing population, its burden is likely to increase. Increasing comorbidity and a desire for less invasive treatment strategies has facilitated the expansion of percutaneous aortic valve therapies. Robust clinical trial data are now available to support the role of transcatheter aortic valve implantation (TAVI) in patients of prohibitive, high and now intermediate surgical risk. The introduction of a Medicare Benefits Schedule reimbursement is likely to see TAVI use grow exponentially in Australia over the next 5 years. Clinical trials evaluating low risk patients may be the final frontier to see TAVI become the standard of care for most patients with severe aortic stenosis.

Complementary and Alternative Medicine for Chronic Musculoskeletal Pain.

A review of randomized clinical trial studies suggests that acupuncture and spinal manipulation may be effective for the treatment of chronic musculoskeletal pain.