Simple percutaneous coronary interventions using the modification of complex coronary lesion with excimer laser

An analysis of long-term clinical outcome following the use of excimer laser coronary atherectomy in a large UK PCI center

BACKGROUND

Excimer laser atherectomy (ELCA) is an established adjunctive technique to facilitate acute success in percutaneous coronary intervention (PCI). Despite this there are a lack of contemporary outcome data, particulary longer-term, forpatients treated with ELCA PCI.

AIMS

To evaluate the contemporary use ofELCA in PCI, the frequency of periprocedural complications and the longer-term outcomes associated with ELCA PCI.

METHODS

This was a retrospective study that included all patients undergoing PCI (with or without ELCA) between April 2005 and May 2021. Relevant features from all cases were downloaded from the patient record and matched to hospital data on mortality on November 22, 2022. Kaplan Meier curves were used to compare mortality between the ELCA PCI and non-ELCA PCI cohorts with a landmark at 1 year. Multivariable Cox regression was performed to assess whether ELCA PCI was independently associated with long-term mortality.

RESULT

There were 21,256 patients in this analysis, of which 448 (2.1%) were treated with ELCA PCI. ELCA PCI was associated with a higher frequency of any periprocedural complication. Median follow-up was 2812 days (IQR, 1577-4245 days) with higher mortality in ELCA PCI (38.2% vs. 29.0%, p < 0.001). However, on multivariable analysis, ELCA PCI was not independently associated with long-term mortality. The TVR frequency in ELCA PCI was 16.7% but TVR was significantly higher for cases of in-stent restenosis (ISR) (29.5%).

CONCLUSION

Despite ELCA PCI being used in higher risk populations with complex coronary artery disease there was no long-term increased mortality associated with the use of this device. ELCA PCI for ISR is highly effective and safe although TVR in this cohort remains high in long-term follow-up.

Endovascular Debulking of Human Carotid Plaques by Using an Excimer Laser Combined With Balloon Angioplasty: An ex vivo Study

Purpose: We aimed to evaluate the safety and effectiveness of applying an excimer laser in debulking human carotid atherosclerotic plaques by investigating the distal debris, plaque luminal gain, and micromorphology of the plaque surface.

Methods: Eighteen plaque samples obtained from carotid endarterectomy (CEA) were randomly allocated to the excimer laser ablation (45 mJ/mm², 25 Hz) alone group (group 1), balloon angioplasty (8 atm) alone group (group 2), and excimer laser ablation combined with balloon angioplasty group (group 3). Hematoxylin–eosin staining and Movat's pentachrome staining were performed on the collected particles to quantify the size and composition of the debris. The superficial micromorphological structure of the plaque lumen surface after device treatments was observed using a scanning electron microscope. Micro-CT, tissue sections, and pathological stainings were applied to the treated plaques. The plaque lumen and artery lumen were three-dimensionally reconstructed using clinical computed tomography angiography and the micro-CT images. Lumen enlargement was set as the main measurement of effectiveness.

Results: Group 3 produced the highest luminal gain (5.40 ± 4.51 mm²), while the other two groups had gains of 4.05 ± 3.20 and 3.77 ± 2.55 mm². Both devices caused disruptions to the plaque lumen surface. Laser ablation exposed the fibers under the endothelium and balloon angioplasty cracked the surface. The mean amounts were 3,611 ± 1,475.4 for group 1, 2,828 ± 1,266.7 for group 2, and 4,400 ± 2,567.9 for group 3. More than 90% of the distal debris was smaller than 10 μm. Group 2 produced the most debris with Feret (maximum caliper diameter) ≥ 40 μm; group 1 had the least. There was little difference in the contents of collagen and reticular fiber in the debris in each group, but a big difference was observed in the contents of fibrin and mucin.

Conclusion: Excimer laser ablation could significantly increase the luminal gain of carotid plaque with high stenosis. Excimer laser combined with balloon angioplasty achieved the highest lumen enlargement. Our result also suggests that the embolic protection strategy needs to be renewed for the application of a plaque debulking device in the future.

Excimer Laser Atherectomy in Percutaneous Coronary Intervention: A Contemporary Review

Excimer laser coronary atherectomy (ELCA) during percutaneous coronary intervention (PCI) has been in use for more than twenty years. While early experiences were not favorable over balloon angioplasty alone, with improvement in operator technique, patient selection and technology, ELCA has established its own niche in contemporary PCI as a safe and effective atherectomy strategy. With growing experience in complex coronary interventions worldwide, ELCA has become one of the essential atherectomy tools offering unique advantages over other atherectomy devices. In the modern era, ELCA is commonly used for patients with in-stent restenosis, stent under expansion, balloon uncrossable lesions and chronic total occlusions. Technical success rates are reported to be >80% in most situations while procedural complication rates such as vessel dissection and perforation among others are reported to average 9% over the past 25 years with improvement over time. In this review, we provide a comprehensive systematic review of the ELCA system, its practical use, indications, and procedural techniques in the contemporary PCI era.

Excimer laser coronary atherectomy prior to paclitaxel-coated balloon angioplasty for de novo coronary artery lesions

This study aimed to evaluate the efficacy and safety of excimer laser coronary atherectomy (ELCA) prior to paclitaxel-coated balloon angioplasty for de novo coronary artery lesions. This retrospective observational study analyzed 118 eligible patients with de novo coronary artery disease whose only percutaneous coronary intervention was a drug-coated balloon angioplasty (i.e., no subsequent stent placement). Data related to our primary outcomes of interest—incidence of major adverse cardiovascular and cerebral events (MACCE), and incidence of procedural complications (bailout stenting and minor complications)—were collected and retrospectively analyzed. ELCA was used significantly more often in the cases of main branch and ostial lesions (i.e., of the circumflex, right coronary, or left anterior descending arteries, or high lateral branch), normally associated with poor treatment outcomes (55.6% vs. 14.3%, p < 0.0005). However, the two groups were not different in terms of cumulative incidence as estimated by the Kaplan–Meier method (log-rank test, p = 0.603) and a causal relationship between ELCA and MACCE was not identified (OR, 2.223; 95% CI, 0.614–8.047; p = 0.223). This study confirms the safety of ELCA prior to paclitaxel DCB angioplasty to treat de novo coronary artery lesions. While difficult-to-treat lesions were significantly more prevalent in the group treated by ELCA, the study revealed similar efficiency as conventional pre-dilation methods. Our findings provide grounds for a prospective randomized trial with consistent lesion and procedural characteristics to evaluate the potential benefits of combining paclitaxel DCB angioplasty following ELCA for de novo coronary artery lesions.

A Hypothetical Vascular Stent with Locally Enlarged Segment and the Hemodynamic Evaluation

Among the interventional stenting methods for treating coronary bifurcation lesions, the conventional treatments still have disadvantages, which include increased intervention difficulties or inadequate supply of blood flow to side branches and may alter the physiological function of downstream organs. Thus, the optimized design of stent geometry needs to be improved based on the specific shape of branches to minimize the complications of inadequate blood flow to the downstream organs and tissues. Our research used 3D modeling and fluid dynamics simulation to design and evaluate a new stent with locally enlarged segment by altering the proportion and length of enlarged surface area based on Bernoulli's equation. The aim is to increase the pressure and blood flow supply at side branches. According to series of blood flow simulations, the stent with 10% enlargement of surface area and length of 3 folders of stent diameter was assigned as the optimized design. The results revealed that by using this design, according to the simulation results, the average pressure on side branches increased at the rate of 43.6%, which would contribute to the adequate blood supply to the downstream organs. Besides, the average wall shear stress (WSS) at sidewalls increased at 9.2% while the average WSS on the host artery wall decreased at 14.1%. There is in the absent of noticeable rise in the total area of low WSS that blows the threshold of 0.5 Pa. Therefore, the present study provides a new method to optimize the hemodynamics features of stent for bifurcation arteries.

Primary percutaneous coronary intervention for a left main bifurcation lesion without stenting using excimer laser with optical coherence tomography guidance: a case report

Background

Optimal strategy for treating bifurcation lesions or lesions with large thrombus in left main disease remains elusive. Excimer laser coronary angioplasty (ELCA) is a therapeutic option for thrombotic lesions in acute coronary syndrome.

Case summary

A 68-year-old man with chest pain was transferred to our emergency department, and subsequently diagnosed as inferior ST-segment elevation myocardial infarction (STEMI). Emergent coronary angiography revealed a 75% stenosis in the left main trunk (LMT). Optical coherence tomography (OCT) showed massive thrombus at the distal LMT to the ostial left anterior descending artery (LAD) and left circumflex artery (LCx). ELCA was performed in the three directions from LMT to proximal LAD, proximal LCx, and obtuse marginal branch. OCT after ELCA showed reduction of thrombus and no apparent plaque rupture or calcification, implying that coronary thrombosis was caused by OCT-defined plaque erosion. Intracoronary electrocardiogram of the LCx showed ST-segment elevation which corresponded to inferior ST-segment elevation, whereas no intracoronary electrocardiogram ST-segment elevation was detected for LAD. Taking all of the data including angiographic appearance, OCT-derived residual lumen size and residual thrombus volume, and strategic options into consideration, we completed percutaneous coronary intervention without stent deployment. He has been free from any cardiac events thereafter for 8 months.

Discussion

Optimal strategy of coronary intervention for bifurcation lesions, especially LMT bifurcations, remains elusive. ELCA may have a potential to safely reduce intracoronary thrombus in patients presenting with acute coronary syndrome with OCT guidance.