Initial experience of a single referral centre using excimer laser coronary atherectomy-assisted expansion in undilatable stents: Excimer laser in undilatable stents.

Aims: Undilatable stents with severe peri-stent calcification are an important cause of target lesion failure and therapeutic options are limited. We report our initial experience with the safety and efficacy of excimer laser coronary atherectomy (ELCA)-assisted expansion of undilatable stents. Methods and results: ELCA was performed with saline, blood and contrast-enhanced trains. All lesions were post-dilated at high pressures and treated with a drug-eluting balloon. Thirty-one lesions with undilatable stents were included at a single centre with experienced operators from March 2016 to February 2021. The mean number of prior procedures for in-stent restenosis was three and 14 lesions had multiple layers of stent. Procedural success (>50% increase in minimal stent diameter [MSD]) and adequate stent expansion (MSD >70% of reference vessel diameter) was achieved in all lesions. At six-month follow-up (N=26 lesions), there were six periprocedural myocardial infarctions due to slow flow, two cardiac deaths and one target lesion revascularisation. There were no perforations. Conclusions: Our niche experience at a centre with experienced operators demonstrated that ELCA led to larger final lumen and stent dimensions in highly selected patients with undilatable stents and recurrent restenosis at the cost of relatively frequent slow flow.

Rotational Atherectomy Combined with Drug Coated-Balloons for in-Stent Restenosis.

BACKGROUND: Refractory coronary in-stent restenosis remains a clinically relevant problem in interventional cardiology despite the use of drug coated balloon angioplasty and further drug eluting stent deployment. In this study, we investigated whether the novel approach of lesion debulking with rotational atherectomy prior to drug coated balloon angioplasty for challenging coronary in-stent restenosis is safe and effective. METHODS: Procedural and registry data was retrospectively analysed for 26 patients who underwent rotational atherectomy immediately followed by drug coated balloon angioplasty to 43 coronary in-stent restenosis lesions with mean follow up of 19 months. RESULTS: Lesion success was achieved in all cases with no major procedural complications. There were no instances of death or myocardial infarction in the follow up period. Target lesion revascularisation occurred in six patients and target vessel revascularisation occurred in eight patients. All target lesion revascularisation occurred in lesions that had already failed drug coated balloon angioplasty without debulking previously while four such lesions were free of lesion failure in the follow up period. CONCLUSIONS: Lesion debulking with rotational atherectomy followed by drug coated balloon angioplasty is a feasible treatment option for selected cases of in-stent restenosis. Further study is needed to fully assess its efficacy in comparison to conventional treatment.

Instantaneous VO2 from a wearable device.

We present a method for calculating instantaneous oxygen uptake (VO2) through the use of a non-invasive and non-obtrusive (i.e. without a face mask) wearable device, together with its clinical evaluation against a standard technique based upon expired gas calorimetry. This method can be integrated with existing wearable devices, we implemented it in the "Device for Reliable Energy Expenditure Monitoring" (DREEM). The DREEM comprises a single lead electrocardiogram (ECG) device combined with a tri-axial accelerometer and is worn around the waist. Our clinical evaluation tests the developed method against a gold standard for VO2, expired gas calorimetry, using an ethically approved protocol comprising active exercise and sedentary periods. The study was performed on 42 participants from a wide sample population including healthy people, athletes and an at-risk health group including persons affected by obesity. We developed an algorithm combining heart rate (HR) and the integral of absolute acceleration (IAA), with results showing a correlation of r = 0.93 for instantaneous VO2, and r = 0.97 for 3 min mean VO2, this is a considerably improved estimation of VO2 in comparison to methods utilising HR and IAA independently.

Balloon Aortic Valvuloplasty in the Transcatheter Valve Era: Single Centre Indications and Early Safety Data in a High Risk Population.

BACKGROUND: The introduction of transcatheter aortic valve implantation (TAVI) has generated a renewed interest in the techniques available to treat high-risk patients with severe aortic stenosis (AS). We report our single centre experience with balloon aortic valvuloplasty (BAV) focussing on indications, procedural success and 30-day outcomes. METHODS: We retrospectively reviewed all patients that underwent BAV procedures at our institution between August 2012 and August 2014. Procedural success and complications were adjudicated according to VARC-2 criteria. RESULTS: Fifty-one consecutive adult patients with severe symptomatic AS underwent a total of 55 BAV procedures. The patients had a mean age of 88±5.7 years and all had extensive comorbidities with a high surgical risk (mean logistic EuroSCORE of 25.22%±14.5%). Indications for BAV included palliation of symptoms n=42 (76%); bridge to definitive valve replacement (n=6, 11%); and evaluation of response (n=6, 11%). The procedure was completed in all patients with no intraprocedural deaths (within 24hours) and low 30-day mortality at 3.9% (n=2). Minor vascular complications occurred in 11.8% (n=6), whilst permanent pacemaker implantation was required in 5.8% (n=3). There were no cases of myocardial infarction, stroke, tamponade, severe aortic regurgitation or major vascular complications during 30-day follow-up. CONCLUSIONS: Balloon aortic valvuloplasty may be performed safely and effectively with high procedural success and low 30-day complications, even in a very high-risk and elderly cohort of patients in whom the role of TAVI is uncertain or inappropriate.

A comparison of entrance skin dose delivered by clinical angiographic c-arms using the real-time dosimeter: the MOSkin.

Coronary angiography is a procedure used in the diagnosis and intervention of coronary heart disease. The procedure is often considered one of the highest dose diagnostic procedures in clinical use. Despite this, there is minimal use of dosimeters within angiographic catheterisation laboratories due to challenges resulting from their implementation. The aim of this study was to compare entrance dose delivery across locally commissioned c-arms to assess the need for real-time dosimetry solutions during angiographic procedures. The secondary aim of this study was to establish a calibration method for the MOSkin dosimeter that accurately produces entrance dose values from the clinically sampled beam qualities and energies. The MOSkin is a real-time dosimeter used to measure the skin dose delivered by external radiation beams. The suitability of the MOSkin for measurements in the angiographic catheterisation laboratory was assessed. Measurements were performed using a 30 × 30 × 30 cm(3) PMMA phantom positioned at the rotational isocenter of the c-arm gantry. The MOSkin calibration factor was established through comparison of the MOSkin response to EBT2 film response. Irradiation of the dosimeters was performed using several clinical beam qualities ranging in energy from 70 to 105 kVp. A total of four different interventional c-arm machines were surveyed and compared using the MOSkin dosimeter. The phantom was irradiated from a normal angle of incidence using clinically relevant protocols, field sizes and source to image detector distance values. The MOSkin was observed to be radiotranslucent to the c-arm beam in all clinical environments. The MOSkin response was reproducible to within 2 % of the average value across repeated measurements for each beam setting. There were large variations in entrance dose delivery to the phantom between the different c-arm machines with the highest observed cine-acquisition entrance dose rate measuring 326 % higher than the lowest measured cine-acquisition entrance dose rate and with the highest measured fluoroscopic entrance dose rate measuring 346 % higher than the lowest measured fluoroscopic entrance dose rate. This comparison of entrance dose delivery across local clinical c-arms demonstrated the disparity in entrance dose delivery across catheterisation laboratories and outlined a need for real-time dose monitoring systems for patients during angiographic procedures. Through use of our calibration method, an average MOSkin calibration of 7.37 mV/cGy was established. The calibration method allowed entrance dose to be measured across a range of beam energies and beam qualities without the input of the c-arm beam characteristics. This calibration factor was proven to reproduce entrance dose values to within 5 % value of the reference dosimeter's response, suggesting potential for further studies and utilisation of the dosimeter in this field.

Twelve-Month Outcomes With a Bioresorbable Everolimus-Eluting Scaffold: Results of the ESHC-BVS Registry at Two Australian Centers.

BACKGROUND: The Absorb bioresorbable vascular scaffold (BVS; Abbott Vascular) is a relatively new type of coronary stent designed to provide temporary vessel scaffolding following percutaneous coronary intervention. International use of the device has grown despite a relative paucity of clinical data regarding the performance of the device and the optimal strategy for its use. We report 12-month clinical data on the Absorb BVS from a real-world registry in order to contribute to the overall understanding of the BVS device. METHODS AND RESULTS: Absorb BVS implantation was attempted in 152 lesions in 100 patients at two Sydney hospitals, as part of the prospective ESHC-BVS registry. Patients selected harbored a range of complex lesions as encountered in real-world practice. Type-C lesions made up 37% of all lesions treated, with 64% of these being long lesions (>20 mm). Device success was achieved in 98.8% of cases. Predilation was performed in all scaffolds and postdilation was performed in 95% of scaffolds to a mean of 19.6 ± 4.6 atm. Twelve-month follow-up data were available for 99% of patients. At 12 months, the cumulative incidence of target-lesion revascularization was 4%, while the incidence of myocardial infarction was 2% and the incidence of scaffold thrombosis was 1%. There were no deaths in the follow-up period. CONCLUSION: In a cohort including complex lesions encountered in real-world practice, the Absorb BVS was associated with low rates of target-lesion revascularization, myocardial infarction, and scaffold thrombosis at 12 months when used with a strategy of meticulous lesion preparation, routine postdilation, and 12 months of dual-antiplatelet therapy.

Everolimus-eluting Bioresorbable Vascular Scaffold Implantation in Real World and Complex Coronary Disease: Procedural and 30-day Outcomes at Two Australian Centres.

BACKGROUND: The Absorb BVS is a new generation of coronary stent designed to provide coronary arteries with mechanical support of a temporary nature, following balloon angioplasty. Clinical trials of the device have shown promising results thus far, however concern surrounds the deliverability of the device in real-world and complex coronary disease, and the possible higher incidence of early scaffold thrombosis when compared to conventional metallic drug-eluting stents. METHODS: Implantation of the Absorb BVS was attempted in 152 lesions in 100 patients at two Sydney teaching hospitals, as part of a prospective registry. Lesions treated reflected a wide spectrum of real-world disease. Young patient age, long lesion length and involvement of the mid-portion of the left anterior descending artery were the strongest factors likely to influence the decision to use the Absorb BVS over conventional metallic stents. There were no restrictions on the lesion length, or on the number of lesions or vessels treated. Type C lesions made up 37% of all lesions treated with 64% of these being long lesions (>20mm). The Absorb BVS was successfully implanted in 98.8% of cases. Post-dilatation was performed in 95% of scaffolds. Peri-procedural non-ST elevation myocardial infarction occurred in four cases. Scaffold thrombosis did not occur in any patient at 30 days follow-up. There was no death, or need for target lesion revascularisation in-hospital or at 30 days. CONCLUSIONS: High rates of procedural success were achieved with minimal complications with use of the Absorb BVS in real-world coronary disease, including complex disease. These results suggest that the reduced deliverability of the device can be largely overcome by meticulous lesion preparation, and that early scaffold thrombosis may be minimised through scaffold post-dilatation.

Prognostic Significance of Peri-procedural Myocardial Infarction in the Era of High Sensitivity Troponin: A Validation of the Joint ACCF/AHA/ESC/WHF Universal Definition of Type 4a Myocardial Infarction with High Sensitivity Troponin T.

AIMS: This study aims to validate the joint ACCF/AHA/ESC/WHF Universal Definition of peri-procedural myocardial infarction (PMI) with high sensitivity troponin T (hsTnT). METHODS: A retrospective cohort study encompassing patients admitted to our institution between May 2012 and April 2013 was performed. RESULTS: 630 patients underwent percutaneous coronary interventions during the study period. Among them, 459 patients met the inclusion criteria and were eligible for analyses. 76.9% of these patients were male, while the mean age was 68.6. PMI was observed in 4.3% of the patients based on the Universal Definition. The predictors of PMI were chronic kidney disease (OR: 3.0, p=0.026), family history of cardiovascular disease (OR: 2.7, p=0.043) and use of IIb/IIIa inhibitors (OR 4.2, p=0.01). MACE was reported in 4.4% of the patients at 12 months, and was significantly and independently associated with PMI (OR 7.3, p=0.003) in a multivariate model which accounted for lesion complexity, patients' baseline clinical information, dual-antiplatelet status at follow-up and various procedural characteristics. The post-procedural hsTnT was much higher in those who suffered MACE than those who did not (156 v.s. 43 ng/L, p<0.001). CONCLUSION: PMI as defined by the current Universal Definition using hsTnT is an independent predictor of adverse clinical outcome at 12 months in patients undergoing PCI. Accordingly, PMI remains a clinically relevant factor in current practice and should be considered a key outcome measure in clinical trials and a potential target for therapy.

Major stent deformation/pseudofracture of 7 Crown Endeavor/Micro Driver stent platform: incidence and causative factors.

AIMS: This is the initial report of stent deformation/pseudofracture of the 7 crown Endeavor/Micro Driver stent platform (2.25-2.75 mm), whereby the post-dilation balloon catches and causes major stent deformation angiographically appearing as a large stent fracture. We sought to determine frequency and cause. METHODS AND RESULTS: Analysis of 1,000 consecutive Endeavor/Micro Driver stents (7 crown) deployed at our institution. Bench testing was also performed by deploying 10 stents in 2.5 mm tubing and then attempting re-crossing with non-compliant balloons. CLINICAL RESULTS: There were 14 cases of major stent deformation/pseudofracture representing an incidence of 1.4% or 1.8% of 775 stents that were post-dilated. Of the 14 deformed stents, re-stenting was required in nine and MACE occurred in five (36%.). Benchtop results: Balloon "catch" was reproducible at an initial frequency of 9% and affected three of the 10 stents. With the use of provocative measures stent deformation occurred in 50% of test stents. CONCLUSIONS: Stent deformation/pseudofracture of the 7 crown Endeavor/Micro Driver platform occurred in 1.8% of cases that were post-dilated. Of these, 36% experience MACE. Deformation can be reproduced on the benchtop. Operators should be aware of the complication, and develop strategies to deal with it.

Final myocardial blush grade predicts troponin I elevation in unstable angina patients undergoing percutaneous intervention.

BACKGROUND: Improved myocardial blush grade is associated with better MACE outcomes in acute myocardial infarction patients but there are no data on myocardial blush grade (MBG) assessment in unstable angina (UA) patients treated with coronary intervention. We sought to evaluate the use of angiographic MBG assessment in a cohort of UA patients treated with angioplasty. METHODS: Three hundred and seventy-two consecutive UA patients (mean age 68+/-1 years) treated with PCI were included. No patients had a pre-procedural troponin I (TnI) elevation. Final MBG was recorded for the territory subserving the PCI treated culprit lesion in each patient and graded 0 (no blush), 1 (minimal blush), 2 (moderate blush) and 3 (normal blush). TnI (normal range <0.1 microg/L) was measured 24h post-procedure. Patients who did not have a TnI elevation (i.e. <0.1 microg/L) were ascribed a value of 0.1 microg/L. Patients were followed up (mean 962+/-83 days) by postal questionnaire. RESULTS: Baseline risk factors were comparable between final MBG groups. There was no significant difference in mortality rate between groups. Post-procedural troponin I elevations were 0.34+/-0.12, 0.68+/-0.26, 0.14+/-0.01 and 0.11+/-0.01 for MBG groups 0, 1, 2 and 3 (p<0.001). Patients with minimal MBG underwent proportionately more target vessel revascularisation (p<0.05). CONCLUSIONS: Improved blush grade in UA patients undergoing PCI is associated with lower post-procedural TnI elevation. Identification of UA patients with poor final MBG may allow a window of opportunity for the administration of adjuvant therapies to improve microvascular perfusion in the future.

New bifurcation stenting technique: shunt stenting.

The optimal treatment of bifurcation lesions remains controversial. We describe a new technique we term shunt stenting. This technique incorporates both the new technology of drug-eluting stents and a novel procedure for optimizing the ostial side branch stent positioning. To date, early angiographic and clinical follow-up have been encouraging.

Actinomycin-eluting stent for coronary revascularization: a randomized feasibility and safety study: the ACTION trial.

OBJECTIVES: We sought to demonstrate the safety and performance of the actinomycin D-coated Multilink-Tetra stent(Guidant Corp., Santa Clara, California) in the treatment of patients with single de novo native coronary lesions. BACKGROUND: Drug-eluting stents (DES) releasing sirolimus or paclitaxel dramatically reduce restenosis. The anti-proliferative drug, actinomycin D, which is highly effective in reducing neointimal proliferation in preclinical studies, was selected for clinical evaluation. METHODS: The multi-center, single-blind, three-arm ACTinomycin-eluting stent Improves Outcomes by reducing Neointimal hyperplasia (ACTION) trial randomized 360 patients to receive a DES (2.5 or 10 microg/cm(2) of actinomycin D) or metallic stent (MS). The primary end points were major adverse cardiac events (MACE) at 30 days, diameter stenosis by angiography, tissue effects, and neointimal volume by intravascular ultrasound (IVUS) at six months. When early monitoring revealed an increased rate of repeat revascularization, the protocol was amended to allow for additional follow-up for DES patients. Angiographic control of MS patients was no longer mandatory. RESULTS: The biased selection of DES patients undergoing IVUS follow-up invalidated the interpretation of the IVUS findings. The in-stent late lumen loss and that at the proximal and distal edges were higher in both DES groups than in the MS group and resulted in higher six-month and one-year MACE (34.8% and 43.1% vs. 13.5%), driven exclusively by target vessel revascularization without excess death or myocardial infarction. CONCLUSIONS: The results of the ACTION trial indicate that all anti-proliferative drugs will not uniformly show a drug class effect in the prevention of restenosis.

High-dose 7-hexanoyltaxol-eluting stent with polymer sleeves for coronary revascularization: one-year results from the SCORE randomized trial.

OBJECTIVES: The Study to COmpare REstenosis Rate between QueST and QuaDDS-QP2 (SCORE) trial was a multicenter, randomized, open-label trial comparing the safety and performance of 13- and 17-mm QuaDDS stents (n = 126) (Quanam Medical Corp., Santa Clara, California/Boston Scientific Corp., Natick, Massachusetts) versus uncoated control stents (n = 140) in focal, de novo coronary lesions. BACKGROUND: The pioneering drug-delivery QuaDDS stent used four to six acrylate polymer sleeves, each loaded with 800 microg of the paclitaxel derivative 7-hexanoyltaxol. METHODS: Clinical end points were assessed at 1, 6, and 12 months post procedure. Quantitative coronary angiography and intravascular ultrasound were performed post procedure and at six-month follow-up. RESULTS: In the QuaDDS group, early stent thrombosis and myocardial infarction (MI) rates were significantly higher, leading to premature cessation of enrollment. For the QuaDDS group, the stent thrombosis rate increased from 3.2% to 10.3% between 1 and 12 months, associated with increased non-Q-wave MI and death rates. The angiographic restenosis rate at six months was reduced from 32.7% (control) to 7.4% (p < 0.0001). However, the primary end point was not met with six-month target vessel revascularization (TVR) rate as well as the composite major adverse cardiac event rates (cardiac death, MI, and TVR) comparable between groups. CONCLUSIONS: Despite angiographic indications of potential anti-restenotic benefit, increased rates of stent thrombosis, MI, and cardiac death associated with the QuaDDS stent show an unacceptable safety profile.

Actinomycin-eluting stent for coronary revascularization: a randomized / feasibility and safety study: the ACTION trial

OBJECTIVES: We sought to demonstrate the safety and formance of the actinomycin D-coated Multilink-Tetra stent(Guidant Corp., Santa Clara,California) in the treatment of patients with single de novo native coronary lesions. BACKGROUND: Drug-eluting stents (DES) releasing sirolimus or paclitaxel dramatically reduce restenosis. The anti-proliferative drug, actinomycin D, which is highly effective in reducing neointimal proliferation in preclinical studies, was selected for clinical evaluation. METHODS: The multi-center, single-blind,three-arm ACTinomycin-eluting stent Improves Outcomes by reducing Neointimal hyperplasia (ACTION) trial randomized 360 patients to receive a DES (2.5 or 10 microg/cm(2) of actinomycin D) or metallic stent (MS). The primary end points were major adverse cardiac events (MACE) at 30days, diameter stenosis by angiography, tissue effects, and neointimal volume by intravascular ultrasound (IVUS) at six months. When early monitoring revealed an increased rate of repeat revascularization, the protocol was amended to allow for additional follow-up for DES patients. Angiographic control of MS patients was no longer mandatory. RESULTS: The biased selection of DES patients undergoing IVUS follow-up invalidated the interpretation of the IVUS findings. The in-stent late lumen loss and that at the proximal and distal edges were higher in both DES groups than in the MS group and resulted in higher six-month and one-year MACE (34.8% and 43.1% vs. 13.5%), driven exclusively by target vessel revascularization without excess death or myocardial infarction...