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.

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.

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.

Disassembly of a rotablator: getting out of a trap.

The rotablator burr rarely becomes trapped within calcified lesions. Manual traction can be ineffective and dangerous. We report a case that illustrates a novel technique involving use of a percutaneous snare in conjunction with partial disassembly of the rotablator device to remove a trapped burr without need for open surgical intervention.

7-hexanoyltaxol-eluting stent for prevention of neointimal growth: an intravascular ultrasound analysis from the Study to COmpare REstenosis rate between QueST and QuaDS-QP2 (SCORE).

BACKGROUND: Inhibition of neointimal tissue growth has been demonstrated in preliminary human feasibility studies with a stent-based polymer sleeve delivering 7-hexanoyltaxol. The Study to COmpare REstenosis rate between QueST and QuaDS-QP2 (SCORE) trial is a human, randomized, multicenter trial comparing 7-hexanoyltaxol (QP2)-eluting stents (qDES) with bare metal stents (BMS) in the treatment of de novo coronary lesions. The purpose of this substudy was to evaluate the acute expansion property and long-term neointimal responses of qDES compared with BMS as assessed by intravascular ultrasound (IVUS). METHODS AND RESULTS: A total of 122 (qDES 66, BMS 56) patients were enrolled into the IVUS substudy. All IVUS images (immediately after the procedure and at 6-month follow-up) were analyzed at an independent core laboratory in a blind manner. At baseline, qDES achieved stent expansion similar to BMS. At follow-up, qDES showed reduced neointimal growth by 70% at the tightest cross section and by 68% over the stented segment (P<0.0001 for both), resulting in a significantly larger lumen in qDES than in BMS. Unlike intracoronary brachytherapy, there was no evidence of negative edge effects, unhealed dissections, or late stent-vessel wall malapposition over the stented and adjacent references segments in either group. CONCLUSIONS: Detailed IVUS analysis revealed that qDES had comparable acute mechanical and superior long-term biological effects to BMS. Although the long-term benefits and limitations of this technology require further investigation, the reduction in neointimal thickenings demonstrated that local delivery of 7-hexanoyltaxol through polymer sleeves augments conventional mechanical treatment of atherosclerotic disease.