Laser coronary angioplasty: history, present and future

The Role of Calcified Nodules in Acute Coronary Syndrome: Diagnosis and Management

Calcified nodules (CNs) are increasingly recognized as critical contributors to the pathophysiology of acute coronary syndrome (ACS). This review provides a comprehensive synthesis of the recent literature, focusing on the prevalence of CNs, their underlying mechanisms, and their implications for the clinical management of coronary artery disease (CAD). CNs are characterized by unique pathophysiological processes, and the diagnosis and treatment of CNs during percutaneous coronary interventions (PCIs) underscore the importance of advanced intravascular imaging techniques, such as optical coherence tomography (OCT) and intravascular ultrasound (IVUS), for precise identification and prognostic evaluation. Current therapeutic strategies aim to modulate CN characteristics, enhance arterial wall stability, and reduce the risk of ACS and sudden cardiac death. This review highlights the impact of CNs in ACS, the role of intravascular imaging in diagnosis, and the importance of targeted interventions to improve clinical outcomes, as by bridging diagnostic insights with emerging atherectomy modalities, this review also seeks to advance the understanding and management of CNs in PCI, fostering improved patient outcomes.

Vascular Calcification: Where is the Cure?

With the progress of aging, the incidence of vascular calcification (VC) gradually increases, which is correlated with cardiovascular events and all-cause death, aggravating global clinical burden. Over the past several decades, accumulating approaches targeting the underlying pathogenesis of VC have provided some possibilities for the treatment of VC. Unfortunately, none of the current interventions have achieved clinical effectiveness on reversing or curing VC. The purpose of this review is to make a summary of novel perspectives on the interventions of VC and provide reference for clinical decision-making.

Treatment of Calcified Lesions Using a Dedicated Super-High Pressure Balloon: Multicenter Optical Coherence Tomography Registry

BACKGROUND

Calcified lesions often lead to difficulty achieving optimal stent expansion. OPN non-compliant (NC) is a twin layer balloon with high rated burst pressure that may modify calcium effectively.

METHODS

Retrospective, multicenter registry in patients undergoing optical coherence tomography (OCT) guided intervention with OPN NC. Superficial calcification with > 180o arc and > 0.5 mm thickness, and/or nodular calcification with > 90o arc were included. OCT was performed in all cases before and after OPN NC, and after intervention. Primary efficacy endpoints were frequency of expansion (EXP) ≥80 % of the mean reference lumen area and mean final EXP by OCT, and secondary endpoints were calcium fractures (CF), and EXP ≥90 %.

RESULTS

50 cases were included; 25 (50 %) superficial, and 25 (50 %) nodular. Calcium score of 4 in 42 (84 %) cases and 3 in 8 (16 %). OPN NC was used alone, or after other devices if further modification was needed, NC in 27 (54 %), cutting in 29 (58 %), scoring in 1 (2 %), IVL in 2 (4 %); or if non-crossable lesion, rotablation in 5 (10 %) cases. EXP ≥80 % was achieved in 40 (80 %) cases with mean final EXP post intervention of 85.7 % ± 8.9. CF were documented in 49 (98 %) cases; multiple in 37 (74 %). There were 1 flow limiting dissection requiring stent deployment and 3 non-cardiovascular related deaths in 6 months follow-up. No records of perforation, no-reflow or other major adverse events.

CONCLUSION

Among patients with heavy calcified lesions undergoing OCT guided intervention with OPN NC, acceptable expansion was achieved in most cases without procedure related complications.

Contemporary Management of Severely Calcified Coronary Lesions

Coronary artery calcification is increasingly prevalent in our patient population. It significantly limits the procedural success of percutaneous coronary intervention and is associated with a higher risk of adverse cardiovascular events both in the short-term and long-term. There are several modalities for modifying calcified plaque, such as balloon angioplasty (including specialty balloons), coronary atheroablative therapy (rotational, orbital, and laser atherectomy), and intravascular lithotripsy. We discuss each modality’s relative advantages and disadvantages and the data supporting their use. This review also highlights the importance of intravascular imaging to characterize coronary calcification and presents an algorithm to tailor the calcium modification therapy based on specific coronary lesion characteristics.

Calcium Modification in Percutaneous Coronary Interventions

Moderate-severe calcification increases procedural complications and impairs long-term prognosis post-PCI. Intravascular imaging (particularly optical coherence tomography [OCT]) is useful in guiding the treatment of calcified lesions. Weighted sum of calcium length, arc, and thickness on OCT can predict adequate stent expansion, identifying when atherectomy is required. With intravascular imaging guidance, various techniques alone or in combination may be used in an algorithmic fashion to modify calcified lesions. Calcium fracture by balloon angioplasty, cutting/scoring balloons, intravascular lithotripsy (IVL), atherectomy devices, or Excimer laser improves stent expansion. Intravascular imaging is essential in the treatment of in-stent restenosis when luminal and/or abluminal peri-strut calcium is present.

Excimer laser technology in percutaneous coronary interventions: Cardiovascular laser society's position paper

Excimer Laser Coronary Atherectomy (ELCA) is a well-established therapy that emerged for the treatment of peripheral vascular atherosclerosis in the late 1980s, at a time when catheters and materials were rudimentary and associated with the most serious complications. Refinements in catheter technology and the introduction of improved laser techniques have led to their effective use for the treatment of a wide spectrum of complex coronary lesions, such as thrombotic lesions, severe calcific lesions, non-crossable or non-expandable lesions, chronic occlusions, and stent under-expansion. The gradual introduction of high-energy strategies combined with the contrast infusion technique has enabled us to treat an increasing number of complex cases with a low rate of periprocedural complications. Currently, the use of the ELCA has also been demonstrated to be effective in acute coronary syndrome (ACS), especially in the context of large thrombotic lesions.

A systematic review of experimental and clinical studies reporting on in situ laser fenestration of aortic endografts

OBJECTIVE

To summarize available in-situ laser fenestration (ISLF) literature, including experimental studies with their subsequent recommendations regarding optimal fenestration technique and fabric; as well as the short and mid-term results of clinical studies.

METHODS

A systematic review of English articles was performed in MEDLINE, the Cochrane Database and EMBASE, following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines by two researchers. The search period was without starting date until the 31^st August 2020, and search terms included were in situ, laser, fenestration, and endograft. Quality assessment of the studies was performed using the Newcastle-Ottawa scale by two other independent researchers.

RESULTS

A total of 19 clinical studies were included, with a total of 428 patients (390 supra-aortic trunk ISLF, 38 visceral vessel ISLF). The technical success was 96.9% and 95.6% supra-aortic and visceral vessel ISLF, respectively. Most studies have less than 12-month follow-up, and the longest available follow-up (in one study) was 5-years for left-subclavian fenestration and 17-months for visceral vessel ISLF. Overall, the quality of the evaluated clinical studies was low. Six experimental studies were included, with the highest level of evidence suggesting fenestration of multifilament polyethylene terephthalate grafts, followed by dilation with either a 6- or 8-mm non-compliant balloon.

CONCLUSION

Experimental studies favour the use of multifilament polyethylene terephthalate , followed by dilation with non-compliant balloons as the most durable "in-vitro" technique for ISLF. Short-term outcomes for arch and visceral vessel revascularization are promising, with low rates of in-hospital mortality, stroke, and end-organ ischemia. Nonetheless, the long-term durability of ISLF is yet to be determined and they should be limited to selected symptomatic or urgent cases.

Review of Laser Therapy in Cardiovascular Diseases

Introduction: In recent years, there has been a rise in laser therapy for the treatment of cardiovascular diseases. Methods: This paper attempted to represent recent advances in laser therapy in cardiovascular tissue repairs. Three standard techniques have been explicitly described here in cardiovascular tissue repairs by laser. Results: One of the advantages of using laser therapy in cardiovascular diseases is its non-invasiveness. It also reduces the treatment process pain and prevents massive surgical incisions and bleeding throughout the operation. Laser therapy can ensure an alternative method to treat the ischemic region of the heart and creating anastomosis of vessels. Conclusion: With professional technologies and endoscopic surgery method development, the role of using lasers has become much more precise and more transparent in cardiovascular diseases.

New Advances in the Treatment of Severe Coronary Artery Calcifications

Coronary artery calcifications are always challenging scenarios for interventional cardiologists. Calcium content in coronary tree directly correlates with male sex, age, Caucasian ethnicity, diabetes, and chronic kidney disease. Intracoronary imaging is useful and necessary to understand calcific lesion features and plan the best percutaneous coronary intervention strategy. Thus, accurate evaluation of patient and lesion characteristics is crucial. For this reason, definition of calcific arc, length, and thickness can suggest the best procedure before stenting and final optimization. In our modern era, different devices are available and all are surprisingly promising.

Therapeutic Approach to Calcified Coronary Lesions: Disruptive Technologies

PURPOSE OF REVIEW

Moderate or severe calcification is present in approximately one third of coronary lesions in patients with stable ischemic heart disease and acute coronary syndromes and portends unfavorable procedural results and long-term outcomes. In this review, we provide an overview on the state-of-the-art in evaluation and treatment of calcified coronary lesions.

RECENT FINDINGS

Intravascular imaging (intravascular ultrasound or optical coherence tomography) can guide percutaneous coronary intervention of severely calcified lesions. New technologies such as orbital atherectomy and intravascular lithotripsy have significantly expanded the range of available techniques to effectively modify coronary calcium and facilitate stent expansion. Calcium fracture improves lesion compliance and is essential to optimize stent implantation. Intravascular imaging allows for detailed assessment of patterns and severity of coronary calcium that are integrated into scoring systems to predict stent expansion, identifying which lesions require atherectomy for lesion modification. Guided by intravascular imaging, older technologies such as rotational atherectomy and excimer laser can be incorporated with newer technologies such as orbital atherectomy and intravascular lithotripsy into an algorithmic approach for the safe and effective treatment of patients with heavily calcified coronary lesions.

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.

Real-life experience of a stent-less revascularization strategy using a combination of excimer laser and drug-coated balloon for patients with acute coronary syndrome

OBJECTIVES

We aimed to test a novel stent-less revascularization strategy using a combination of excimer laser coronary angioplasty (ELCA) and drug-coated balloon (DCB) for patients with acute coronary syndrome (ACS).

BACKGROUND

Percutaneous coronary intervention with drug eluting stents is a standard invasive treatment for ACS. Some unsolved issues however remain, such as stent thrombosis and bleeding risks associated with dual antiplatelet therapy.

METHODS

Consecutive ACS patients were planned to receive either a DCB application following ELCA without a stent implantation or conventional revascularization with a coronary stent. The endpoints were (i) major cardiac adverse events (MACEs), defined as the composite of cardiac death, myocardial infarctions, and target lesion revascularization; (ii) target vessel revascularization (TVR); and (iii) angiographic outcome.

RESULTS

Since a greater than expected number of patients allocated to the stent-less treatment arm eventually received a bailout stenting, the following 3 as-treated groups were compared; DCB with ELCA group (N = 60), Stent with ELCA group (N = 23), and Stent without ELCA group (N = 85). During a mean follow-up period of 420 ± 137 days, and with angiographic 6- and 12-month-follow-up rates of 96.7%, 87%, and 81.2%, and 50%, 65.2%, and 45.9%, respectively, the MACE rate did not differ across the groups (10%, 4.3%, and 3.5%; P = 0.22) while an incidence of TVR was more common (15%, 0, and 4.7%; P = 0.02) and the diameter stenosis at 6-months of follow-up was greater (25.7 ± 18.2, 14.9 ± 13.1 and 16.2 ± 15.4%; P = 0.002) in the DCB with ELCA group.

CONCLUSIONS

The stent-less revascularization strategy with DCB and ELCA was associated with a higher occurrence of restenosis in ACS patients.

Coronary Intervention with the Excimer Laser: Review of the Technology and Outcome Data

Excimer laser coronary atherectomy (ELCA) is a long-established adjunctive therapy that can be applied during percutaneous coronary intervention (PCI). Technical aspects have evolved and there is an established safety and efficacy record across a number of clinical indications in contemporary interventional practice where complex lesions are routinely encountered. The role of ELCA during PCI for thrombus, non-crossable or non-expandable lesions, chronic occlusions and stent under-expansion are discussed in this review. The key advantage of ELCA over alternative atherectomy interventions is delivery on a standard 0.014-inch guidewire. Additionally, the technique can be mastered by any operator after a short period of training. The major limitation is presence of heavy calcification although when rotational atherectomy (RA) is required but cannot be applied due to inability to deliver the dedicated RotaWire^TM (Boston Scientific), ELCA can create an upstream channel to permit RotaWire passage and complete the case with RA - the RASER technique.

Aspirin reduces platelet aggregation during high-energy excimer laser

BACKGROUND AND OBJECTIVES

Excimer laser is used clinically in arterial revascularization procedures. This study evaluated the efficacy of aspirin in reducing platelet aggregation during high-energy excimer lasing.

STUDY DESIGN/MATERIALS AND METHODS

Platelet rich plasma (PRP) from seven rabbits was circulated in a dual organ chamber with aspirin added to one and the other was control. PRP was irradiated using an excimer laser (308 nm; 45 mJ/mm(2); 25 Hz; 5 minutes) via a 2.0 mm laser catheter. Platelet aggregation (particle volume) was measured by laser-light scattering. Morphology was evaluated by phase contrast and electron microscopy.

RESULTS

Baseline platelet volume was 3.4 microm(3) for both control and aspirin groups. Following lasing, platelet volume peaked at 102.2 +/- 18.5 microm(3) for control compared to 43.1 +/- 49.2 microm(3) for aspirin-treated PRP (P < 0.0001).

CONCLUSION

Aspirin reduces large platelet aggregates but not small aggregates by 58% during lasing of PRP.

First clinical experience of a novel penetration catheter for patients with severe coronary artery stenosis

The study aimed to evaluate the efficacy of a novel penetration catheter for severe coronary artery disease. Severe coronary artery diseases such as chronic total occlusions or severe calcified stenoses sometimes obstruct the subsequent crossing of balloon catheter after successful wire crossing. A novel penetration over-the-wire catheter has been developed for severe coronary artery disease. The main shaft is a coreless stainless coil that consists of eight stranded stainless wires to cross through a severe stenosis by manual rotation. This device was applied during percutaneous coronary intervention for patients with severe coronary artery disease obstructing the subsequent crossing of balloon or microcatheters after successful wire crossing. Initial results were examined. Fourteen eligible patients were enrolled consecutively. Among those, 10 patients had chronic total occlusion and 7 patients showed severe angiographical calcification. The device was successfully crossed through the lesion and enabled subsequent dilatation in all patients without any complication. This new device enables the crossing of severe coronary artery stenoses and therefore favors further dilatation in this lesion subset.