Analysis of low-speed rotational atherectomy for the reduction of platelet aggregation

The Incidence of Complication in the Perioperative Period of Rotational Atherectomy in Patients With Acute Coronary Syndrome: A Retrospective Study of Low Speed Versus High Speed

The safety and efficacy of rotational atherectomy (RA) in patients with acute coronary syndrome (ACS) treated with different rotational speeds remain unclear. This was an observational retrospective registry study. Between February 2017 and January 2022, a total of 283 patients with ACS were treated with RA. The patients were divided into 2 groups: the low-speed group (130,000 to 150,000 rotations/min [rpm],182 cases) and the high-speed group (160,000 to 220,000 rpm, 101 cases) according to the maximum RA speed. The outcomes analyzed were procedural complications; incidence of heart failure, stent thrombosis, and cardiac death during hospitalization; and 30-day major cardiovascular and cerebrovascular events. Patients in the low-speed RA group had a higher incidence of vasospasm during RA (15.4% vs 6.9%, p = 0.040), whereas the incidence of slow blood flow was higher in the high-speed RA group (16.5% vs 27.7%, p = 0.031). There was no significant difference in other complications or in 30-day major cardiovascular and cerebrovascular events between the 2 groups. Moreover, logistic regression analysis identified rotational speed (160,000 to 220,000 rpm) as a predictor of slow flow during RA (odds ratio 1.900, 95% confidence interval 1.006 to 3.588, p = 0.048). For every 10,000-rpm increase in rotational speed, the risk of slow flow increased by 27% (odds ratio 1.273, 95% confidence interval 1.047 to 1.547, p = 0.015). In conclusion, patients with ACS treated with a lower RA speed (130,000 to 150,000 rpm) had a higher risk of vasospasm, whereas those treated with higher speeds (160,000 to 220,000 rpm) had a higher incidence of slow flow. High rotational speed (160,000 to 220,000 rpm) is an independent risk factor for slow flow during RA in patients with ACS.

Feasibility of rotational atherectomy in patients with acute coronary syndrome: favorable in-hospital outcomes and clinical importance of complexed coronary atherosclerosis

The feasibility of rotational atherectomy (RA) during percutaneous coronary intervention (PCI) in patients who present with acute coronary syndrome (ACS) remains fully unsettled. We retrospectively evaluated 198 consecutive patients who underwent RA during PCI from 2009 to 2020. All patients underwent intracoronary imaging (intravascular ultrasound 96.5%, optical coherence tomography 9.1%, both 5.6%) during PCI. Patients who underwent RA during PCI were divided into two groups: ACS (n = 49; unstable angina pectoris, n = 27; non-ST-elevation myocardial infarction, n = 18, and ST-elevation myocardial infarction, n = 4) and chronic coronary syndrome (CCS) (n = 149). The RA procedural success rate was comparable between in the ACS and CCS groups (93.9 vs. 89.9%, P = 0.41). No significant differences were observed in procedural complications and in-hospital death between the groups. The incidence of major adverse cardiovascular event (MACE) after 2 years was significantly higher in ACS group compared with CCS group (38.7 vs. 17.4%, log-rank P = 0.002). Multivariable Cox regression analysis identified SYNTAX score or CABG SYNTAX score > 22 (hazard ratio (HR) 2.66, 95% confidence interval (CI) 1.40-5.06, P = 0.002) and mechanical circulatory support during the procedure (HR 2.61, 95% CI 1.21-5.59, P = 0.013) as predictors of MACE at 2 years, but not ACS on index admission (HR 1.58, 95% CI 0.84-2.99, P = 0.151). RA procedure is feasible as a bail-out strategy for ACS lesions. However, more complexed coronary atherosclerosis and mechanical circulatory support during RA procedure, but no ACS lesions were associated with worse mid-term clinical outcomes.

Rotational atherectomy of calcified coronary lesions: current practice and insights from two randomized trials

With growing experience, technical improvements and use of newer generation drug-eluting stents (DES), recent data showed satisfactory acute and long-term results after rotational atherectomy (RA) in calcified coronary lesions. The randomized ROTAXUS and PREPARE-CALC trials compared RA to balloon-based strategies in two different time periods in the DES era. In this manuscript, we assessed the technical evolution in RA practice from a pooled analysis of the RA groups of both trials and established a link to further recent literature. Furthermore, we sought to summarize and analyze the available experience with RA in different patient and lesion subsets, and propose recommendations to improve RA practice. We also illustrated the combination of RA with other methods of lesion preparation. Finally, based on the available evidence, we propose a simple and practical approach to treat severely calcified lesions.

Intravascular Lithotripsy for the Treatment of Severely Calcified Coronary Artery Disease: A DISRUPT CAD III Intravascular Ultrasound Substudy

BACKGROUND

Coronary intravascular lithotripsy (IVL) has emerged as a novel technique for the treatment of severely calcified coronary lesions. We evaluated the mechanism and efficacy of IVL in facilitating optimal stent implantation in heavily calcified coronary lesions using intravascular ultrasound (IVUS).

METHODS

Forty-six patients were initially enrolled as a part of the Disrupt CAD III study. Of these, 33 had pre-IVL, 24 had post-IVL, and 44 had post-stent IVUS evaluation. The final analysis was performed on 18 patients who had IVUS images interpretable at all three intervals. The primary endpoint was increase in minimum lumen area (MLA) from pre-IVL to post-IVL treatment to post-stenting.

RESULTS

Pre-IVL, MLA was 2.75 ± 0.84 mm2, percent area stenosis was 67.22 % ± 20.95 % with maximum calcium angle of 266.90° ± 78.30°, confirming severely calcified lesions. After IVL, MLA increased to 4.06 ± 1.41 mm2 (p = 0.0003), percent area stenosis decreased to 54.80 % ± 25.71 % (p = 0.0009), and maximum calcium angle decreased to 239.40° ± 76.73° (p = 0.003). There was a further increase in MLA to 6.84 ± 2.18 mm2 (p < 0.0001) and decrease in percent area stenosis to 30.33 % ± 35.08 % (p < 0.0001) post-stenting with minimum stent area of 6.99 ± 2.14 mm2. The success rate of stent delivery, implantation, and post-stent dilation was 100 % post-IVL.

CONCLUSION

In this first study evaluating the mechanism of IVL using IVUS, the primary endpoint of increase in MLA from pre-IVL to post-IVL treatment to post-stenting was successfully achieved. Our study showed that the use of IVL-assisted percutaneous coronary intervention is associated with improved vessel compliance, facilitating optimal stent implantation in de novo severely calcified lesions.

Clinical expert consensus document on rotational atherectomy from the Japanese association of cardiovascular intervention and therapeutics: update 2023

The Task Force on Rotational Atherectomy of the Japanese Association of Cardiovascular Intervention and Therapeutics (CVIT) proposed the expert consensus document to summarize the techniques and evidences regarding rotational atherectomy (RA) in 2020. Because the revascularization strategy to severely calcified lesions is the hottest topic in contemporary percutaneous coronary intervention (PCI), many evidences related to RA have been published since 2020. Latest advancements have been incorporated in this updated expert consensus document.

TIcagrelor in Rotational Atherectomy to Reduce TROPonin Enhancement: The TIRATROP Study, A Randomized Controlled Trial

BACKGROUND

Because rotational atherectomy (RA) is associated with arterial trauma and platelet activation, patients treated with RA may benefit from more potent antiplatelet drugs. The aim of this trial was to assess the superiority of ticagrelor over clopidogrel in reducing post procedure troponin release.

METHODS

TIRATROP (TIcagrelor in Rotational Atherectomy to reduce TROPonin enhancement) is a multicenter double-blind randomized controlled trial that included 180 patients with severe calcified lesions requiring RA who received either clopidogrel (300 mg loading dose, then 75 mg/d) or ticagrelor (loading dose 180 mg then 90 mg twice daily). Blood samples were collected at the beginning (T0), and 6, 12, 18, 24 and 36 h after the procedure. Primary end point was troponin release within the first 24 h using area under the curve analysis (troponin level as a function of time).

RESULTS

The mean age of patients was 76 ± 10 years, 35% had diabetes. RA was used to treat 1, 2 or 3 calcified lesions in 72%, 23% and 5% of patients, respectively. Troponin release within the first 24 h was similar in both the ticagrelor (adjusted mean ±SD of ln AUC 8.85 ± 0.33) and the clopidogrel (8.77 ± 0.34, p = 0.60) arms. Independent predictors for troponin enhancement were acute coronary syndrome presentation, renal failure, elevated C-Reactive protein and multiple lesions treated with RA.

CONCLUSION

Troponin release did not differ among treatment arms. Our results suggest that greater platelet inhibition does not affect periprocedural myocardial necrosis in the setting of RA.

Shock Wave Intravascular Lithotripsy: Shock the Rock

Complex coronary artery disease with severe coronary calcification can be challenging to treat, with a higher risk of procedural complications and major adverse cardiac events. Intravascular lithotripsy (IVL) is a pioneering technology for the treatment of critically calcified coronaries. IVL utilizing localized pulsatile sonic pressure waves at low pressure provides a novel approach for lesion preparation of severely calcified plaques. The deliverability and ease of use are also likely to increase access and use of IVL, and combination therapy with other devices shows promise.

Clinical and angiographic success and safety comparison of coronary intravascular lithotripsy: An updated meta-analysis

Background

Intravascular lithotripsy (IVL) can be used to assist stent deployment in severe coronary artery calcifications (CAC).

Methods

Studies employing IVL for CAC lesions were included. The primary outcomes included clinical and angiographic success. The secondary outcomes, including lumen gain, maximum calcium thickness, and calcium angle at the final angiography site, minimal lumen area site, and minimal stent area site, were analyzed by the random-effects model to calculate the pooled standardized mean difference. Tertiary outcomes included safety event ratios.

Results

Seven studies (760 patients) were included. The primary outcomes: pooled clinical and angiographic success event ratio parentage of IVL was 94.4% and 94.8%, respectively. On a random effect model for standard inverse variance for secondary outcomes showed: minimal lumen diameter increase with IVL was 4.68 mm (p-value < 0.0001, 95% CI 1.69–5.32); diameter decrease in the stenotic area after IVL session was −5.23 mm (95 CI –22.6–12.8). At the minimal lumen area (MLA) and final minimal stent area (MSA) sites, mean lumen area gain was 1.42 mm² (95% CI 1.06–1.63; p < 0.00001) and 1.34 mm² (95% CI 0.71–1.43; p < 0.00001), respectively. IVL reduced calcium thickness at the MLA site (SMD −0.22; 95% CI −0.40–0.04; P = 0.02); calcium angle was not affected at the MLA site. The tertiary outcomes: most common complication was major adverse cardiovascular events (n = 48/669), and least common complication was abrupt closure of the vessel (n = 1/669).

Conclusions

Evidence suggests that IVL safely and effectively facilitates stent deployment with high angiographic and clinical success rates in treating severely calcified coronary lesions.

White thrombi on optical coherence tomography after rotational atherectomy of severely calcified coronary lesions

PURPOSE

Rotational atherectomy (RA) has improved percutaneous treatment of severely calcified coronary lesions, but the "no-reflow" phenomenon remains a serious complication. Platelet activation by RA may contribute to no-reflow, and the use of optical coherence tomography (OCT) to test the effect of RA on white thrombus could confirm platelet activation indirectly.

METHODS

We analyzed 53 consecutive patients with severely calcified lesions on coronary angiography. All patients were examined with OCT. In total, 20 patients who received RA and for whom OCT imaging was performed before and after RA and stent implantation comprised the RA group. The remaining 33 patients formed the control group, for whom OCT imaging was performed before balloon dilatation and after stent implantation.

RESULTS

The patients in the RA group were older and had a higher incidence of diabetes mellitus. In the control group, there was no thrombogenesis during the procedure, whereas in the RA group, all the target vessels had white thrombi on OCT after RA. The average number of white thrombi per lesion after RA was 7.23 ± 4.4, and the average length of white thrombus was 0.51 ± 0.33 mm. Statistical analysis with Pearson's correlation coefficient showed that thrombus load was related to burr size (r = 0.575, p = 0.040) and number of rotations (r = 0.599, p = 0.031).

CONCLUSION

White thrombi during RA can be verified by performing OCT. Treating calcified lesions with RA may enhance thrombogenesis. These data suggest using appropriate therapy to avoid no-reflow during RA.

Calcium Modification Therapies in Contemporary Percutaneous Coronary Intervention

Coronary Artery Calcification (CAC) has been known to be associated with worse Percutaneous Coronary Intervention (PCI) short- and long-term outcomes. Nowadays, with the increased prevalence of the risk factors leading to CAC in the population and also more PCI procedures done in older patients and with the growing number of higher-risk cases of Chronic Total Occlusion (CTO) PCI and PCI after Coronary Artery Bypass Grafting (CABG), severe cases of CAC are now encountered on a daily basis in the catheterization lab and remain a big challenge to the interventional community, making it crucial to identify cases of severe CAC and plan a CAC PCI modification strategy upfront. Improved CAC detection with intravascular imaging helped identify more of these severe CAC cases and predict response to therapy and stent expansion based on CAC distribution in the vessel. Multiple available therapies for CAC modification have evolved over the years. Familiarity with the specifics and special considerations and limitations of each of these tools are essential in the choice and application of these therapies when used in severe CAC treatment. In this review, we discuss CAC pathophysiology, modes of detection, and different available therapies for CAC modification.

[Focus on high speed rotational atherectomy by Rotablator in 2021 and datas from France PCI registry]

Developed in the late 1980s, rotational atherectomy has raised a lot of hope for its innovative principle of selective ablation, allowing volume reduction (instead of redistribution) of atherosclerotic plaque, while sparing healthy tissue. Long shunned for its disappointing results on restenosis, the Rotablator finally reasserted itself in the 2000s; era of drug eluting stents and coronary angioplasty boom, thus generating emergence of complex lesions. Indeed, the Rotablator has demonstrated an undeniable benefit in complex (type C) and calcified lesions preparation (before stenting), with a procedural success rate of 95%. Although these lesions only represent a small amount (2-3%) of percutaneous coronary interventions (PCI), they remain a technical impasse for plain-old balloon angioplasty strategy, making the Rotablator more suitable for these resistant lesions' treatment. Registry data attest the safety of this therapy, with a rate of peri-procedural complications and in-hospital mortality comparable to conventional angioplasty (France PCI register). However, certain specific, rare but serious complications (burr entrapment, broken Rotawire, coronary perforation) justify trained teams, perfect knowledge of the equipment, and strict compliance with good practice guidelines. In 2018, the rise of a new method of atherectomy by intra-vascular lithotripsy (Shockwave) has coincided with Rotablator decreasing activity (this finding being biased by a general decrease in PCI activity due to Covid pandemic). This therapeutic range's enhancement revolutionizes calcified lesions treatment, tending towards precise targeting of each indication, depending in particular on calcium distribution's anatomy in the plaque.

Safety and efficacy of rotational atherectomy in heavily calcified lesions involving coronary aneurysms

Percutaneous transluminal rotational atherectomy (PTRA) is one of the most used techniques to facilitate percutaneous coronary intervention in heavily calcified coronary lesion (CCL). Coronary aneurysms (CAs) are detected in 1.2-4.9% of coronary angiogram. The presence of CA and CCL is infrequent but not rare, where the use of PTRA may be mandatory despite the high risk. After a complex procedure of PTRA in a CCL with CA we decided to investigate about this particular condition. We identified a total of six patients among 174 consecutive percutaneous coronary intervention (3.4%). All the procedures showed good stent expansion in the absence of major complications, such as no-reflow or coronary perforation. Cardiovascular death, rehospitalization for myocardial infarction and target lesion failure were not reported at follow-up (252 ± 152 days).

Safety and efficacy of coronary intravascular lithotripsy for calcified coronary arteries- a systematic review and meta-analysis

Objectives: Intravascular lithotripsy (IVL) clinical efficacy and safety in the treatment of calcified coronary artery disease (CAC) is not well known. We sought to assess IVL safety and efficacy in CAC. Methods: A comprehensive online databases search were performed to identify intravascular lithotripsy studies in patients with coronary artery disease. The primary outcome was IVL related change in the mean pre and post-procedural diameter of the coronary artery. Results: A total of 4 studies with 282 patients were included. The mean pre-IVL coronary diameter for all patients was 1.01 mm, while the mean post-IVL coronary diameter was 2.70 mm. The mean pre-post IVL diameter difference of coronary arteries on the pooled analysis was significantly lower by 4.08 mm (95% CI -4.94 to -3.30, p ≤ 0.00001). The Overall increase in the post-IVL lumen diameter was significantly higher than the pre-IVL diameter with a mean difference of -4.16 (95% CI -5.08 to -3.24, p = 0.000001). However, compared to pre-IVL, there was a significant reduction in the overall mean difference of luminal calcium angle after IVL of the stented coronary arteries (0.09, 95% CI 0.002-0.16, p = 0.01). Conclusion: Intravascular lithotripsy can offer a significant improvement in the vessel lumen to facilitate coronary stent delivery and deployments in severely calcified coronary arteries.

Clinical expert consensus document on rotational atherectomy from the Japanese association of cardiovascular intervention and therapeutics

Rotational atherectomy (RA) has been widely used for percutaneous coronary intervention (PCI) to severely calcified lesions. As compared to other countries, RA in Japan has uniquely developed with the aid of greater usage of intravascular imaging devices such as intravascular ultrasound (IVUS) or optical coherence tomography (OCT). IVUS has been used to understand the guidewire bias and to decide appropriate burr sizes during RA, whereas OCT can also provide the thickness of calcification. Owing to such abundant experiences, Japanese RA operators modified RA techniques and reported unique evidences regarding RA. The Task Force on Rotational Atherectomy of the J apanese Association of Cardiovascular Intervention and Therapeutics (CVIT) has now proposed the expert consensus document to summarize the contemporary techniques and evidences regarding RA.

Novel Micro Crown Orbital Atherectomy for Severe Lesion Calcification: Coronary Orbital Atherectomy System Study (COAST)

Supplemental Digital Content is available in the text.

Percutaneous coronary intervention of severely calcified lesions carries a high risk of adverse events despite the use of contemporary devices. The Classic Crown Orbital Atherectomy System (OAS) was safe and effective for severely calcified lesion preparation in the ORBIT II study (Evaluate the Safety and Efficacy of OAS in Treating Severely Calcified Coronary Lesions) but was not optimized for tight lesions. COAST (Coronary Orbital Atherectomy System Study) evaluated the safety and efficacy of calcified lesion preparation before stent implantation with the Diamondback 360 Micro Crown Coronary OAS, designed for use in tighter lesions.

Rotablation in the Very Elderly - Safer than We Think?

BACKGROUND/PURPOSE

Calcified coronary artery stenosis remains a challenge for Percutaneous Coronary Intervention (PCI). Calcium modification is facilitated by rotablation and is used in 1-3% of cases. Data on rotablation in patients ≥80 years is limited and perceived to be high risk. We compared PCI with rotablation and outcomes between patients ≥80 years and those <80 years.

METHODS/MATERIALS

Retrospective analysis was performed of consecutive patients who underwent rotablation and PCI from 3 United Kingdom (UK) PCI Centres (2014-2017). In-hospital outcomes (composite of stroke, myocardial infarction, death, emergency coronary artery bypass graft surgery, vascular damage, coronary perforation, advanced AV-block, bleeding and renal impairment) and 30 day mortality risk score was compared between groups.

RESULTS

213 patients were included. 33.3% (n = 71) were ≥80 years. Baseline and angiographic characteristics were similar in the two groups. Older patients were more likely to present with acute coronary syndrome (ACS) (≥80 years 53.5% vs. 33.8% in <80 years, p = 0.006) and had increased hospital stay (≥80 years 2.8 days (±6.0) vs. 1.3 days (±1.9) <80 years, p = 0.009). Majority of PCI were performed through radial access (≥80 years 91.5% vs. 88.0% <80 years, p = 0.43). In-hospital composite outcomes were similar between the groups (≥80 years 5.6% vs. 4.9% <80 years, p = 1.0). The 30-day mortality risk score demonstrated a higher average risk of 2.5% in ≥80 years versus under 1% risk in <80 years (p < 0.001).

CONCLUSION

This study demonstrates that outcomes after rotablation in the very elderly are similar to younger patients despite being high risk and presenting with ACS.

Reappraisal Value of a Modified Rotational Atherectomy Technique in Contemporary Coronary Angioplasty Era

Objectives

To introduce a modified rotational atherectomy (RA) procedure and investigate the early and midterm outcomes of the RA-facilitating diversified percutaneous coronary intervention (PCI) in a large group of aged patients with higher cardiovascular risk.

Background

Previous studies about the outcomes of RA were limited with small sample size and low-risk population.

Methods

Between January 2013 and November 2015, 1169 consecutive patients treated with modified RA-facilitated PCI were retrospectively enrolled, including de novo calcified lesions and in-stent restenosis. Patients were regularly followed up for at least 1 year. Major adverse cardiac events (MACE) were analyzed for all participants by different strategies. Cox regression analysis was performed to identify risk factors for the events.

Results

The median age of patients was 75 years, with 11.7% of patients on maintenance hemodialysis. Most lesions (99.9%) were complex (American Heart Association type B2/C), and 68.3% were treated with RA + drug-eluting-stent (DES). Successful angiography was achieved in 97.8% cases, with 1.7% (20/1169) experiencing coronary perforation (including guidewire perforation). The incidence of MACE was 20.5% and 26.8% at 1-year and 2-year follow-up and were mainly driven by target lesion revascularization (TLR) (10.3% and 12.5%, respectively). The strategy of RA + DES had the lowest 2-year MACE, compared with the RA + drug-coated balloon and RA + plain old balloon angioplasty (14.5%, 30.5%, and 26.0%, respectively).

Conclusions

The modified RA technique is a safe and effective tool in the contemporary PCI era, even in high-risk patients. The TLR rate was relatively high but acceptable in such complex lesions.

Minimizing thermal damage to vascular nerves while drilling of calcified plaque

OBJECTIVE

Drilling of calcified plaque (DCP) inside the artery is a method for removing calcified plaques. This study investigated the effect of drill. To validate the maximum temperature calculated by computer simulation, this value was also measured by an experimental on a phantom model.

RESULTS

Increasing drill bit diameter during drilling would increase the temperature in vascular nerves. In a drill bit with a diameter of 4 mm, the risk of thermal necrosis in vascular nerves of the artery wall decreased by 8.57% by changing the drill from WC to NT. The same value for a drill bit with a diameter of 6 mm was 10.17%. However, the trend of the generated temperature in the vascular nerves did not change significantly with change of the material and diameter of the drill bit. The results showed that for DCP with the least risk of thermal necrosis in vascular nerves and subsequently the lowest risk of restenosis, coagulation and thermal stroke of the patient, the best option is to use a drill bit with a diameter of 4 mm and NT material for drilling.

A Novel Rotablator Technique (Low-Speed following High-Speed Rotational Atherectomy) Can Achieve Larger Lumen Gain: Evaluation Using Optimal Frequency Domain Imaging

Background

While the evaluation of burr speed was discussed regarding platelet aggregation, the association between platform speed and acute lumen gain of rotational atherectomy remains unknown.

Methods

Through the evaluation of the potential of low-speed rotational atherectomy (LSRA) in in-vitro experiments, minimum lumen diameter (MLD) and minimum lumen area (MLA) after conventional high-speed rotational atherectomy (HSRA group) and those after LSRA following HSRA (LSRA+HSRA group) treated by 1.5 mm burrs were measured by optical frequency domain imaging (OFDI) in 30 consecutive human lesions.

Results

The in-vitro experiments demonstrated that MLD and MLA after LSRA+HSRA were significantly larger (MLD: LSRA+HSRA=1.50 ±0.05 mm, HSRA= 1.43 ±0.05 mm, p=0.015; MLA: LSRA+HSRA= 1.90 ±0.17 mm², HSRA= 1.71±0.11 mm², and p= 0.037), requiring more crossing attempts (LSRA= 134 ±20 times, HSRA= 72 ±11 times, and p< 0.001). In human studies, there was no significance in reference vessel diameter and lesion length before the procedure between two groups. MLDs after LSRA+HSRA were significantly larger than those in HSRA (LSRA+HSRA= 1.22 ±0.16 mm, HSRA= 1.07 ±0.14 mm, and p= 0.0078), while MLAs after LSRA+HSRA tended to be larger (LSRA+HSRA= 1.79 ±0.51 mm², HSRA= 1.55 ±0.47 mm², and p= 0.19). There was no significance in the occurrence of in-hospital complication, including slow flow or no reflow, major dissection, and procedural myocardial infarction, between LSRA+HSRA and HSRA.

Conclusions

LSRA can achieve larger lumen gain compared, whereas HSRA can pass calcified lesions easily. Combination of LSRA and HSRA is a safe and feasible strategy for severely calcified lesions in clinical practice.

The Current Status of Lithoplasty in Vascular Calcifications: A Systematic Review

Background. Lithoplasty is a method of alleviating vessel stenosis by using localized high-speed pressure waves to disrupt calcium deposits. A systematic review of the literature was performed to summarize the early outcomes of lithoplasty in peripheral and coronary artery disease. Methods. We searched EMBASE, MEDLINE, and the Cochrane Central Register of Controlled Trials from database inception to July 2018 for original studies describing the use of lithoplasty. Study selection and data extraction were performed in duplicate, with a third author resolving discrepancies. Results. A total of 9 records were included from the 201 studies eligible for screening. In total, 211 patients with vascular calcification lesions underwent lithoplasty. The patients on average had an age of 73.2 years and had a maximum follow-up period of 5.5 months. Most lesions (72%, 152/212) were in peripheral artery beds, with the remainder occurring in coronary vessels. Lesioned vessels typically had severe calcium burden 62.6% (131/210), with an average initial stenosis of 76.6% (range, 68.1%-77.8%). After treatment, the average residual stenosis was 21.0% (range, 13.3%-26.2%), with a mean acute gain of vessel diameter of 2.5 mm. A limited number of type D dissections occurred, with a total of 2.4% (5/211) of patients requiring stent implantation. Conclusions. Recent studies suggest that lithoplasty is a promising intervention to decrease vessel stenosis in both peripheral artery disease and coronary artery disease, with minimal occurrence of major adverse events. Further research studies, with more rigorous study designs, are needed to determine the effectiveness of lithoplasty in vascular calcifications.

Association between debulking area of rotational atherectomy and platform revolution speed-Frequency domain optical coherence tomography analysis

OBJECTIVES

In this study, we sought to investigate the association between revolution speed of rotational atherectomy (RA) and debulking area assessed by frequency domain-optical coherence tomography (FD-OCT).

BACKGROUND

The number of patients with severe calcified coronary artery disease requiring treatment with calcium ablation, such as RA, is increasing. However, there is little evidence available regarding the association between debulking area and revolution speed during RA.

METHODS

We retrospectively investigated 30 consecutive severely calcified coronary lesions in 29 patients who underwent RA under FD-OCT guidance. The association between preset revolution speed of RA and burr size-corrected debulking area of the calcified lesion was evaluated using a multivariable regression model with nonlinear restricted-cubic-spline, which can help assess nonlinear associations between variables.

RESULTS

The median age of study participants was 73 years (quartile 65-78); 82.8% were male. The median burr size was 1.5 mm (1.5-1.75); median total duration of ablation was 120 s (100-180). FD-OCT revealed that the post-procedural minimum lumen area increased significantly from 1.64 mm² (1.40-2.09) to 2.45 mm² (2.11-2.98) (p < .001). In addition, the burr size-corrected debulking area increased significantly as the preset revolution speed decreased (p = .018), especially when the revolution speed was less than 150,000 rpm. This result implies that additional lumen gain will be obtained by decreasing rpm when the burr speed is set at <150,000 rpm.

CONCLUSIONS

FD-OCT demonstrated that RA with lower revolution speed, below 150,000 rpm, has the potential to achieve greater calcium debulking effect in patients with severe calcified coronary lesions.

Stentablation with Rotational Atherectomy for the Management of Underexpanded and Undilatable Coronary Stents

Stentablation with rotational atherectomy for the management of undilatable underexpanded coronary stents is a unique application associated with excellent periprocedural and in-hospital outcomes. Data regarding long-term outcomes remains limited, however the procedure appears to be associated with high prevalence of target lesion revascularization. Given the complexity of such lesions and few available interventional remedies; it is a reasonably safe and widely available approach of which operators should be aware. When stentablation is performed, the principles which guide contemporary rotational atherectomy and percutaneous coronary intervention, including intravascular imaging, should be applied.

Acute coronary syndrome - Still a valid contraindication to perform rotational atherectomy? Early and one-year outcomes

BACKGROUND

Rotational atherectomy (RA) is an acknowledged method of percutaneous treatment of highly calcified or fibrotic coronary lesions. However, using the rotablator system in patients presenting with acute coronary syndromes (ACS) remains controversial and is considered as a relative contraindication. The aim of our study was to assess in-hospital and 1-year outcomes in patients undergoing RA presenting with ACS, in comparison to elective RA procedures.

METHODS

This single-center observational study included all consecutive patients who underwent RA and PCI in our institution from April 2008 to October 2015. All patients were subsequently divided into two groups based on clinical presentation: stable angina group (SA) and ACS group. Primary endpoints were in-hospital and 1-year all-cause mortality and 1-year major adverse cardiac events (MACE). Secondary endpoints were procedural success and in-hospital complications.

RESULTS

The study included 207 patients, 164 (79%) in SA group and 43 (21%) in ACS group. In-hospital mortality was higher in patients with ACS (4.7% vs. 0%, p=0.01). Procedural success was similar in both groups, 93% in ACS groups vs. 92.7% in SA group, p=0.94. There were no significant differences in the rate of periprocedural complications (4.7% vs. 10.4%, p=0.25), however postprocedural complications were more frequent in ACS group. At 1-year follow-up MACE rate and mortality were numerically higher, however statistically not significant (25.6% vs. 16.5%, p=0.17 and 16.3% vs. 7.9%, p=0.10; respectively).

CONCLUSIONS

Despite higher mortality and complication rate in ACS group observed in postprocedural period, we found no significant difference in 1-year outcomes in comparison to elective patients. Procedural success of RA in ACS patients is similar to elective patients with SA and this procedure should be considered in case of urgent indications, if no other options of treatment exist.

The incidence of slow flow after rotational atherectomy of calcified coronary arteries: A randomized study of low speed versus high speed

OBJECTIVES

The purpose of this randomized trial was to compare the incidence of slow flow between low-speed and high-speed rotational atherectomy (RA) of calcified coronary lesions.

BACKGROUND

Preclinical studies suggest that slow flow is less frequently observed with low-speed than high-speed RA because of less platelet aggregation with low-speed RA.

METHODS

This was a prospective, randomized, single center study. A total of 100 patients with calcified coronary lesions were enrolled and randomly assigned in a 1:1 ratio to low-speed (140,000 rpm) or high-speed (190,000 rpm) RA. The primary endpoint was the occurrence of slow flow following RA. Slow flow was defined as slow or absent distal runoff (Thrombolysis in Myocardial Infarction [TIMI] flow grade ≤ 2).

RESULTS

The incidence of slow flow in the low-speed group (24%) was the same as that in the high-speed group (24%) (P = 1.00; odds ratio, 1.00; 95% confidence interval, 0.40-2.50). The frequencies of TIMI 3, TIMI 2, TIMI 1, and TIMI 0 flow grades were similar between the low-speed (TIMI 3, 76%; TIMI 2, 14%; TIMI 1, 8%; TIMI 0, 2%) and high-speed (TIMI 3, 76%; TIMI 2, 14%; TIMI 1, 10%; TIMI 0, 0%) groups (P = 0.77 for trend). The incidence of periprocedural myocardial infarction was the same between the low-speed (6%) and high-speed (6%) groups (P = 1.00).

CONCLUSIONS

This randomized trial did not show a reduction in the incidence of slow flow following low-speed RA as compared with high-speed RA (UMIN ID: UMIN000015702). © 2016 Wiley Periodicals, Inc.

Safety and Efficacy of Immediate Rotational Atherectomy in Nondilatable Calcified Coronary Lesions Complicated by Coronary Artery Dissection (RAISE)

OBJECTIVES

To examine the safety and efficacy of immediate rotational atherectomy (RA) in nondilatable calcified coronary lesions complicated by coronary dissection during percutaneous coronary intervention (PCI).

BACKGROUND

In the presence of coronary dissection in nondilatable calcified coronary lesions, conservative management is suggested to permit the dissection to heal prior to treatment with RA. However, many patients have frequent angina attacks and some patients develop serious complications during this period.

METHODS

One hundred and nighty-eight patients with severe coronary calcification underwent PCI, and were randomized into immediate (n = 105) or delayed RA group (n = 93) when coronary dissections occur. The primary endpoint of the present study was all-cause death including cardiac and non-cardiac death in 4 years follow-up. Non-fatal myocardial infarction, stent thrombosis, cardiac tamponade, stroke, target lesion revascularization, New York Heart Association (NYHA) class IV heart failure were analyzed as secondary end points.

RESULTS

At a follow-up of 4 years, event-free survival rates were not statistically different between the immediate and delayed RA group (81.9% vs 80.6%, P = 0.820). Rates of PCI- and RA-related major adverse cardiac events (MACE) and severe RA-related complications were not statistically different between groups. Luminal loss was not significantly different between the immediate and delayed RA group as evaluated by Intravascular ultrasound (IVUS). Two cases in the delayed RA group experienced myocardial infarction during the 4-week waiting.

CONCLUSION

This study indicates that immediate RA during PCI is safe and effective in patients with coronary artery dissection.

Orbital Atherectomy for Treating De Novo Severely Calcified Coronary Narrowing (1-Year Results from the Pivotal ORBIT II Trial)

Percutaneous coronary intervention of severely calcified lesions has historically been associated with major adverse cardiac event (MACE) rates as high as 30%. In the ORBIT II (Evaluate the Safety and Efficacy of OAS in Treating Severely Calcified Coronary Lesions) trial, treatment of de novo severely calcified lesions with the Diamondback 360° Coronary Orbital Atherectomy System (OAS) resulted in low rates of procedural and 30-day adverse ischemic events. The long-term results from this trial have not been reported. We sought to determine the 1-year outcomes after orbital atherectomy of severely calcified coronary lesions. ORBIT II was a single-arm trial enrolling 443 subjects at 49 US sites with severely calcified lesions usually excluded from randomized trials. OAS utilizes a centrifugal differential sanding mechanism of action for plaque modification prior to stent implantation. After OAS drug-eluting stents were implanted in 88.2% of the patients. The primary safety end point was 30-day MACE, the composite of cardiac death, myocardial infarction, or target vessel revascularization [TVR]. The present analysis reports the 1-year follow-up results from ORBIT II. One-year data were available in 433 of 443 patients (97.7%), with median follow-up time of 16.7 months. The 1-year MACE rate was 16.4%, including cardiac death (3.0%), myocardial infarction (9.7%), and target vessel revascularization (5.9%). The 1-year target lesion revascularization rate was 4.7%, and stent thrombosis occurred in 1 patient (0.2%). Independent predictors of 1-year MACE and target vessel revascularization were diameter stenosis at baseline and the use of bare-metal stents. In patients with severely calcified lesions who underwent percutaneous coronary intervention, the use of OAS was associated with low rates of 1-year adverse ischemic events compared with historical controls. This finding has important clinical implications for the selection of optimum treatment strategies for patients with severely calcified lesions.

Rotational atherectomy: Technical update

Percutaneous coronary intervention is currently the most common form of revascularization for symptomatic coronary artery disease. In elderly, diabetic and renal patients, there is an increased prevalence of calcified coronary disease. Rotational atherectomy (RA) can be useful in the treatment of these lesions. Plaque removal was initially proposed as an alternative to balloon angioplasty, hence RA required high-velocity protocols with large-sized burrs (over 2.0 mm). With a high incidence of acute complications and disappointing restenosis rates, the use of RA dwindled. However, the advent of drug-eluting stents, which significantly decreased the rate of restenosis, led to the repositioning of RA as an adjunctive technique in the preparation of densely calcified lesions, improving stent delivery and expansion. In recent years, a better understanding of the mechanism of action of RA has changed it from a plaque debulking to a compliance modifying technique. As a result, RA has become less aggressive, using smaller size burrs and lower rotational speeds. This conservative approach has improved immediate results, with increased safety and better long-term outcomes. In this review paper, the technique of RA is explained in the light of current knowledge.

[The indispensable instrument for rotational atherectomy]

Rotational atherectomy is the treatment of choice for calcified coronary lesions. It should not be used routinely but only in some appropriate cases, especially when the successful deployment of a stent may be uncertain. Complications are rare but serious. Several cases of "off label" use, however, have been reported in the literature without additional complications.

Rotational atherectomy: a "survivor" in the drug-eluting stent era

Mechanical debulking of coronary plaques with rotational atherectomy (RA) has been used for more than 20 years during percutaneous coronary interventions (PCI). Modification of plaque characteristics may be accomplished with selective ablation of inelastic fibrocalcific tissue. The use of RA, though reduced with the development of bare-metal stents (BMS) and even more with drug-eluting stents (DES), has never been completely abandoned. The present review will analyze reasons for conflicting results obtained in large series and randomized trials on this topic in the past, and will identify criteria for an appropriate use in current times.

Study to determine the clinical significance of HEmolysis During Orbital AtheRectomy (CLEAR study)

PURPOSE

To evaluate the incidence of clinically evident hemolysis associated with orbital atherectomy used to treat severe peripheral artery disease.

METHODS

The observational CLEAR study enrolled 31 subjects (16 men; mean age 71 ± 10 years, range 44-92) with claudication (58.1%) or critical limb ischemia (38.7%) who underwent orbital atherectomy with the Diamondback 360 system at 4 US centers. The 42 lesions in 31 limbs were located in the superficial femoral (n = 19, 45.2%), popliteal (n = 8, 19.0%), and tibial arteries (n = 15, 35.8%). The majority of lesions (34, 81.0%) were de novo; moderate or severe calcification was identified in 90.5% of cases. Lesion and procedural parameters were analyzed at a core laboratory. Blood samples were collected during and post procedure and analyzed for markers of hemolysis. The primary endpoint was the occurrence of clinically significant hemolysis. The secondary endpoints included the occurrence of any clinical symptoms/signs potentially related to hemolysis. Statistical analysis was performed to identify predictors for hemolysis.

RESULTS

Laboratory evidence of hemolysis was seen in 11 (35.5%) subjects. No one met the clinical event criteria, and so the primary endpoint of the study was not reached. The secondary endpoints were hypertensive crisis (1, 3.2%) and transient hemoglobinuria (3, 9.7%). Lower glomerular filtration rates, calcified plaque, long atherectomy runs, and solid crown selection were independent predictors of hemolysis.

CONCLUSION

There was no clinically significant hemolysis after orbital atherectomy. The results of this study will enable users to predict conditions that predispose to high levels of red cell hemolysis following orbital atherectomy and to take appropriate measures to limit its occurrence.

Increase in serum troponin-I following rotational atherectomy reliably predicts the occurrence of reversible wall motion abnormalities

BACKGROUND

There is growing evidence that microdebris pulverized by rotational atherectomy (RA) may have a deleterious effect on coronary microcirculation and ventricular contraction. However, the incidence and the predictors of worsening of left ventricular wall motion following RA are unknown.

METHODS

Thirty patients without a known previous anterior wall myocardial infarction who underwent RA-facilitated angioplasty for de novo lesions of left anterior descending coronary artery were evaluated. Global and anterior wall regional left ventricular ejection fraction (LVEF and AREF) were analyzed before and after RA. Serum troponin-I, CK, and CK-MB concentrations were assayed.

RESULTS

Target lesion length was greater (P=0.03), post-procedural minimal lumen diameter was smaller (P<0.01), and serum troponin-I immediately after RA was higher (P=0.01) in 16 patients with a decrease in the AREF of at least 15% than in those without. Stepwise logistic regression analysis identified one independent predictor of such worsening of AREF, troponin-I> or =0.1 ng/ml immediately after the procedure (P<0.01), with sensitivity of 81%, specificity of 79%, and relative risk of 3.8.

CONCLUSIONS

Our results suggest that RA can cause substantial deterioration in left ventricular wall motion. Serum troponin-I, a sensitive indicator of myocardial damage, may be useful in predicting reversible LV wall motion abnormalities following RA.

Rotational Coronary Atherectomy in Acute ST-Segment Elevation Myocardial Infarction

The usual large thrombus load encountered in acute ST-elevation myocardial infarctions increases the likelihood for slow-flow or no-reflow during percutaneous coronary intervention. The use of rotational atherectomy in this clinical scenario is usually prohibitive due to the potential for further induction of platelet activation and aggregation by the rotating burr. In this case presentation, primary percutaneous coronary intervention for an acute ST-elevation myocardial infarction was performed. Due to the complex vessel geometry, pretreatment with atherectomy was mandatory with the only available atherectomy device in the laboratory: Rotablator. This case represents the first report on the successful use of rotational coronary atherectomy in the setting of acute ST-elevation myocardial infarction.

Meta-Analysis of randomized trials of percutaneous transluminal coronary angioplasty versus atherectomy, cutting balloon atherotomy, or laser angioplasty

OBJECTIVES

We conducted a systematic overview (meta-analysis) of randomized trials of balloon angioplasty versus coronary atherectomy, laser angioplasty, or cutting balloon atherotomy to evaluate the effects of plaque modification during percutaneous coronary intervention.

BACKGROUND

Several mechanical approaches have been developed that ablate or section atheromatous plaque during percutaneous coronary interventions to optimize acute results, minimize intimal injury, and reduce complications and restenosis.

METHODS

Sixteen trials (9,222 patients) constitute the randomized controlled experience with atherectomy, laser, or atherotomy versus balloon angioplasty with or without coronary stenting. Each trial tested the hypothesis that ablative therapy would result in better clinical or angiographic results than balloon dilation alone.

RESULTS

Short-term death rates (<31 days) were not improved by the use of ablative procedures (0.3% vs. 0.4%, odds ratio [OR] 0.94 [95% confidence interval 0.46 to 1.92]), but periprocedural myocardial infarctions (4.4% vs. 2.5%, OR 1.83 [95% CI 1.43 to 2.34]) and major adverse cardiac events (5.1% vs. 3.3%, OR 1.54 [95% CI 1.25 to 1.89]) were increased. Angiographic restenosis rates (6,958 patients) were not improved with the ablative devices (38.9% vs. 37.4%, OR 1.06 [95% CI 0.97 to 1.17]). No reduction in revascularization rates (25.2% vs. 24.5%, OR 1.04 [95% CI 0.94 to 1.14]) or cumulative adverse cardiac events rates up to one year after treatment were seen with ablative devices (27.8% vs. 26.1%, OR 1.09 [95% CI 0.99 to 1.20]).

CONCLUSIONS

The combined experience from randomized trials suggests that ablative devices failed to achieve predefined clinical and angiographic outcomes. This meta-analysis does not support the hypothesis that routine ablation or sectioning of atheromatous tissue is beneficial during percutaneous coronary interventions.

Beneficial effect of rotational atherectomy with low platform speed on late outcomes

BACKGROUND

Modification of rotational atherectomy (RA) procedures might be expected to alter restenosis rates.

METHODS AND RESULTS

From June 1998 (period 2), platform speed was decreased to 150,000-160,000 rpm from the 170,000-190,000 rpm performed from August 1997 to May 1998 (period 1). Patients for the two periods (period 1: 62 patients, 70 lesions; period 2: 85 patients, 91 lesions) demonstrated comparable clinical and angiographic baseline data, allowing immediate and late outcomes to be evaluated for comparison. Restenosis rates in periods 1 and 2 were 57.9% and 33.8%, respectively (P=0.01). Platform speed and lesion length were independent predictors of restenosis by multivariate logistic regression analysis.

CONCLUSIONS

RA with a low platform speed (150,000-160,000 rpm) can be performed with a high success rate and with a lower incidence of restenosis than with a high platform speed (170,000-190,000 rpm).

Current status of rotational atherectomy

Despite the increasing use of percutaneous transluminal coronary angioplasty and intracoronary stent placement for the treatment of obstructive coronary artery disease, a large subset of coronary lesions cannot be adequately treated with balloon angioplasty and/or intracoronary stenting alone. Such lesions are often heavily calcified or fibrotic and undilatable with the present balloon technology and attempts to treat them with balloon angioplasty or intracoronary stent placement often lead to vessel dissection or incomplete stent deployment with resultant adverse outcomes. Rotational atherectomy remains a useful niche device for the percutaneous treatment of such complex lesions, usually as an adjunct to subsequent balloon angioplasty and/or intracoronary stent placement. In contrast to balloon angioplasty or stent placement that widen the coronary lumen by displacing atherosclerotic plaque, rotational atherectomy removes plaque by ablating the atherosclerotic material, which is dispersed into the distal coronary circulation. Other lesion subtypes amenable to treatment with this modality include ostial and branch-ostial lesions, chronic total occlusions, and in-stent restenosis. This review discusses the technique and principles of rotational atherectomy, the various treatment strategies for its use (including adjunctive pharmacotherapy), the lesion-specific applications for this device, and the complications unique to this modality. Recommendations are also made for its use in the current interventional era.

Randomized trial of Rotational Atherectomy Versus Balloon Angioplasty for Diffuse In-stent Restenosis (ROSTER)

BACKGROUND

Various autopsy and intravascular ultrasound (IVUS) studies have shown neointimal proliferation as the main mechanism of in-stent restenosis (ISR) responsible for >95% of luminal narrowing while stent struts are not compressed. ISR of diffuse type has a high incidence of recurrence (up to 70%) after balloon angioplasty (PTCA). Tissue ablation with percutaneous rotational coronary atherectomy (PRCA) may be more efficacious compared to tissue compression or extrusion after PTCA for the interventional treatment of diffuse ISR.

METHODS

The Rotational Atherectomy Versus Balloon Angioplasty for Diffuse In-Stent Restenosis (ROSTER) trial is a single-center, randomized trial comparing PRCA to PTCA (both with IVUS guidance) in the treatment of diffuse ISR in 200 patients. In the PRCA group (n = 100), rotablation was performed using a burr-to-artery ratio >0.7 followed by adjunctive balloon dilatation at low pressure (4-6 atm). In the PTCA group (n = 100), high-pressure (>12 atm) balloon dilatation was performed using an optimal size balloon. The study's primary end point was target lesion revascularization (TLR) at 9 months and secondary end points included clinical events at 1 year and angiographic restenosis in a substudy of the last 75 patients enrolled.

RESULTS

Baseline clinical and angiographic variables were comparable between the 2 groups with similar procedural and angiographic success, but a higher rate of repeat stenting occurred in the PTCA group (31% vs 10%; P <.001). Although the angiographic acute luminal gain was similar between the 2 groups, IVUS analysis revealed lower residual intimal hyperplasia area after PRCA versus PTCA (2.1 +/- 0.9 mm2 vs. 3.3 +/- 1.8 mm2; P =.005). At a mean follow-up of 12 +/- 2 months, there were 2 deaths, 3 myocardial infarctions, and 3 coronary artery bypass graft procedures in each group. TLR incidence was 32% in the PRCA group and 45% in the PTCA group (P =.042), with a similar trend noted in the angiographic substudy.

CONCLUSION

The ROSTER trial for diffuse ISR revealed both PRCA and PTCA to be safe and effective, but PRCA resulted in less residual intimal hyperplasia, lower repeat stent use, and decreased TLR.

A comparative study of rotational atherectomy in acute and stable coronary syndromes in the modern era

Percutaneous rotational coronary atherectomy (PRCA) is commonly used in the percutaneous treatment of diffuse, calcified coronary lesions in stable coronary syndromes (SCSs) and facilitates successful delivery and deployment of balloons and stents. Early experience with PRCA cautioned its use in acute coronary syndromes (ACSs). However, the evolution of the PRCA technique and improved antiplatelet pharmacotherapy has broadened its use in ACSs also. A total of 1,112 consecutive patients with an ACS (n=269) or SCS (n=843) who underwent PRCA of 1,483 lesions were examined retrospectively to evaluate the angiographic and short-term clinical outcomes. Troponin-I was elevated in 33.3% of the ACS group and in 0.6% of the SCS group at baseline (p<0.001). Angiographic complications occurred more frequently in the ACS group (18.6% vs 13.1%, p=0.02). There was no difference in major complications between the groups (ACS 1.1% vs SCS 0.8%; p=0.44). The incidence of any periprocedural creatinine kinase-MB elevation was 17.1% versus 18.9% (p=NS) and 30-day major adverse cardiac events (death, disabling stroke, creatine kinase-MB >3 times the upper limit of normal, urgent revascularization) was 5.9% versus 4.6% (p=NS) when comparing the ACS and SCS groups, respectively. With current techniques and antiplatelet therapy, PRCA can be safely performed in ACSs when lesion morphology dictates, with outcomes comparable to that achieved in SCSs. Although angiographic complications occurred more frequently in the ACS group, this did not result in a significantly higher incidence of postprocedural myonecrosis or 30-day major adverse cardiac events.

Acute and Long-Term Outcomes of Rotational Atherectomy in Small (<3.0 mm) Coronary Arteries

Conventional balloon angioplasty (BA) of small coronary arteries (SCA) is followed by a high rate of restenosis. Rotational atherectomy may be effective as an alternate treatment of stenoses unsuitable for other devices. The purpose of this study was to assess the efficacy of RA in the treatment of SCA. A retrospective analysis was performed of 226 lesions in 159 consecutive patients who underwent RA of SCA (mean diameter = 2.36 +/- 0.49 mm). One hundred forty-eight lesions (65.5%) were type B2 or C of AHA/ACC criteria. Follow-up angiography was performed at 3 and 6 months after the procedure. Procedural success was achieved in 96.9% of patients. The mean burr-to-artery ratio was 0.74 +/- 0.17. Adjunctive BA and stent implantation were needed in 94.2% and 22.6% of lesions, respectively. Minimal lumen diameter (MLD) increased from 0.66 +/- 0.35 mm to 1.97 +/- 0.58 mm (P < 0.01). Angiographic complications consisted of acute reclosure (3.5%), no reflow/slow flow (12.4%), and coronary artery perforation (1.8%). No death, Q-wave myocardial infarction (MI), or coronary artery bypass graft (CABG) occurred during the initial hospitalization. Restenosis rates at 3 and 6 months were 40.6% and 44.2%, respectively, and target lesion revascularization (TLR) rates were 28.5% and 33.0%, respectively. Restenosis and TLR rates during follow-up were comparable among patients who underwent RA + adjunctive BA versus patients who underwent RA + stenting. Long-term clinical follow-up was complete in 143 patients over a mean period of 348 +/- 166 days. The survival free from cardiac death, MI, CABG or repeated BA was 59.6% at 1 year. In conclusion, RA of SCA has relatively high restenosis rates, but may be appropriate for more complex, calcified lesions unsuitable for other devices.