Successful removal of an entrapped rotablation burr by extracting drive shaft sheath followed by balloon dilatation

Successful Retrieval of Rota Burr After Driveshaft Fracture

Rotational atherectomy is an effective procedure for heavily calcified lesions and those that cannot be crossed using conventional percutaneous coronary intervention (PCI) devices. Here, we report a rare case of intracoronary burr entrapment in the coronary artery due to burr disconnection from the driveshaft. A 67-year-old man undergoing hemodialysis for nephrosclerosis presented with exertional chest discomfort. Coronary angiography revealed stenotic lesions in the right coronary artery, and PCI was performed using a Rotawire Floppy. During the procedure, the disconnected burr was successfully removed without surgery using the child-in-mother technique with a guide extension catheter. Notably, the patient remained hemodynamically stable throughout the procedure and his recovery was uncomplicated. He was discharged on the second postprocedural day. At the 6-month follow-up, the patient remained asymptomatic with no evidence of myocardial ischemia. This report informs clinicians of the possibility of burr disconnection and the non-surgical intervention used for its removal.

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.

Aortic cusp perforation during rotational atherectomy: a case report

Background

Rotational atherectomy has become increasingly utilised over the past decade. Although a relatively safe procedure in appropriately trained physicians' hands, there are a number of recognised complications.

Case summary

We describe the case of a 64-year-old female who presented with chest pain and was diagnosed with non-ST-segment elevation acute coronary syndrome. A transthoracic echocardiogram (TTE) showed normal biventricular function and no valve disease. Invasive coronary angiogram was performed which revealed a severely calcified ostial right coronary artery (RCA) disease which was felt to be the culprit of the presentation. Balloon dilatation was unsuccessful, therefore, rotational atherectomy with an Amplatz left 0.75 guide and a 1.5 mm rota-burr was utilised and improved calcium burden. This was complicated by ostial dissection, treated with stenting. A TTE following the procedure revealed moderate aortic regurgitation (AR). The patient was discharged as she remained asymptomatic. An outpatient transoesophageal echocardiogram performed eight months later showed evidence of severe eccentric AR. Cardiac magnetic resonance imaging confirmed severe AR with left ventricular dilatation. Repeat angiogram 10 months after index procedure revealed in-stent restenosis, and the patient was accepted by heart multidisciplinary team for aortic valve replacement and grafting of RCA.

Discussion

As the field of rotational atherectomy continues to expand, we propose that novel complications such as reported in this case may become recognised. Finally, we stress the importance of multi-modality imaging in the investigation and timely planning of interventions in the management of these patients.

Electroplating a miniature diamond wheel for grinding of the calcified plaque inside arteries

A miniature grinding wheel (0.85 mm diameter) was fabricated by nickel (Ni)-diamond electroplating on a thin (0.65 mm outer diameter) flexible hollow stainless steel drive shaft to remove the calcified plaque in coronary and peripheral arteries by atherectomy procedure. To coat electrically nonconductive diamond grits, the drive shaft was submerged in a pile of diamond grit during Ni electroplating. The electroplating current density and temperature were investigated for better surface finishing and Faraday efficiency. The electroplating time to obtain the designed coating thickness was modeled based on Faraday's law of electrolysis and the geometry of drive shaft, wheel, and diamond grit. To validate the miniature wheel performance in atherectomy, grinding experiments were conducted on an atherectomy cardiovascular simulator with a calcified plaque surrogate. The wheel motion, material removal rate, and wheel surface wear were studied via high-speed camera imaging and laser confocal microscopy. The grinding wheel with 80,000 rpm rotational speed had an orbital speed of 14,300 rpm around the 1.5 mm diameter plaque surrogate lumen. After grinding for 120 s, the plaque surrogate inner diameter was enlarged to 3.03 mm, and no wear or loss of diamond abrasive was observed on the grinding wheel. This study demonstrated that the proposed electroplating process for fabricating miniature grinding wheels could effectively remove the calcified plaque surrogate. This research could lead to a more effective and safer atherectomy device with sub-mm miniature diamond wheels to treat lesions deep in coronary and peripheral arteries.

[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.

How Should I Get Prepared for and Treat Rota Burr Entrapment in a Focally Underexpanded and Restenosed Stent: A Case Report

Although high-speed rotational atherectomy has been successfully used in selected cases of stent underexpansion secondary to heavy peri-stent calcification, a higher risk of burr entrapment demands extreme caution and surgical back-up on site. The main cause of this complication is the lack of diamond dust on the back end of the burr, which prevents backward ablation of tissues when retracted. To date, only few reports of successful burr retrieval using percutaneous bailout techniques have been published. We report a case of burr entrapment within a previously implanted left circumflex artery stent which was successfully recaptured using the dual catheter technique; following the retrieval the patient underwent routine percutaneous coronary intervention.

Modifiable and unmodifiable factors associated with slow flow following rotational atherectomy

Background

Although several groups reported the risk factors for slow flow during rotational atherectomy (RA), they did not clearly distinguish modifiable factors, such as burr-to-artery ratio from unmodifiable ones, such as lesion length. The aim of this retrospective study was to investigate the modifiable and unmodifiable factors that were associated with slow flow.

Methods

We included 513 lesions treated with RA, which were classified into a slow flow group (n = 97) and a non-slow flow group (n = 416) according to the presence or absence of slow flow just after RA. The multivariate logistic regression analysis was performed to find factors associated with slow flow.

Results

Slow flow was inversely associated with reference diameter [Odds ratio (OR) 0.351, 95% confidence interval (CI) 0.205–0.600, p<0.001], primary RA strategy (OR 0.224, 95% CI 0.097–0.513, p<0.001), short single run (≤15 seconds) (OR 0.458, 95% CI 0.271–0.776, p = 0.004), and systolic blood pressure (BP) ≥ 140 mmHg (OR 0.501, 95% CI 0.297–0.843, p = 0.009). Lesion length (every 5 mm increase: OR 1.193, 95% CI 1.093–1.301, p<0.001), angulation (OR 2.054, 95% CI 1.171–3.601, p = 0.012), halfway RA (OR 2.027, 95% CI 1.130–3.635, p = 0.018), initial burr-to-artery ratio (OR 1.451, 95% CI 1.212–1.737, p<0.001), and use of beta blockers (OR 1.894, 95% CI 1.004–3.573, p = 0.049) were significantly associated with slow flow.

Conclusions

Slow flow was positively associated with several unmodifiable factors including lesion length and angulation, and inversely associated with reference diameter. In addition, slow flow was positively associated with several modifiable factors including initial burr-to-artery ratio and use of beta blockers, and inversely associated with primary RA strategy, short single run, and systolic blood pressure just before RA. Application of this information could help to improve RA procedures.

When Things Get Stuck: Gear Entrapment and Other Complications of Chronic Total Occlusion Percutaneous Coronary Intervention

Complex coronary artery intervention stresses the limits of both the operator's skills as well as the equipment being used for the procedure. This article is focused on avoiding, recognizing and dealing with device failure and gear entrapment during complex coronary intervention. The operator must understand how to avoid these complications by understanding the limits of devices and the need for adequate vessel preparation. This article focuses on giving the reader an algorithmic approach to recognizing when device failure/entrapment occurs and what specific maneuvers can be done to retrieve different devices and equipment safely.

Percutaneous Retrieval of an Entrapped Rotational Atherectomy Burr Using Novel Technique of Controlled Traction and Counter Traction

Burr entrapment is a rare but serious complication during rotational atherectomy (RA). The Japanese have termed this the Kokeshi phenomenon named after a wooden doll found in northern Japan consisted of a simple trunk but a large head akin to the Rotablator (Mechery et al., 2016; Kaneda et al., 2000). The reason underlying this complication is the lack of diamond dust on the back end of the burr (Lin et al., 2013). The burr is olive-shaped and has diamond coating at its distal surface for antegrade ablation. The proximal part is smooth without diamonds, which prevents backward ablation of tissues when retracted (Lin et al., 2013; Dahdouh et al., 2013). Rota entrapment usually needs surgical management with coronary artery bypass grafting (CABG) surgery. To date, only few cases of successful non-traumatic retrieval using nonsurgical bailout techniques have been published (Grise et al., 2002). We report a case of burr entrapment within the left anterior descending (LAD) artery which was successfully retrieved by combination of multiple maneuvers and the patient underwent routine PCI following the retrieval.

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.

A Practical Approach to the Management of Complications During Percutaneous Coronary Intervention

Percutaneous coronary intervention relieves symptoms in patients with chronic ischemic heart disease resistant to optimal medical therapy and alters the natural history of acute coronary syndromes. However, adverse procedural outcomes may occur during the intervention. Knowledge of possible complications and their timely management are essential for the practicing cardiologist and can be life-saving for the patient. In this review, the authors summarize potential complications of percutaneous coronary intervention focusing on their practical management.

Rotational Atherectomy: A Contemporary Appraisal

Rotational atherectomy (RA) is an atheroablative technology that enables percutaneous coronary intervention for complex, calcified coronary lesions. RA works on the principle of 'differential cutting' and preferentially ablates hard, inelastic, calcified plaque. The objective of RA use has evolved from plaque debulking to plaque modification to enable balloon angioplasty and optimal stent expansion. The clinical experience over the past 30 years has informed the current best practices for RA with use of smaller burr sizes, short ablation runs a 'pecking' motion, and avoidance of sudden decelerations. This has led to significant improvements in procedural safety and a reduced rate of associated complications. This article reviews the principles, clinical indications, contemporary evidence, technical considerations and complications associated with the use of RA.

Comparison of complications with a 1.25-mm versus a 1.5-mm burr for severely calcified lesions that could not be crossed by an intravascular ultrasound catheter

Since intravascular imaging such as intravascular ultrasound (IVUS) can provide useful information for rotational atherectomy (RA), intravascular imaging should be attempted before RA. However, some calcified lesions do not allow imaging catheters to cross before RA. Although small burrs (1.25 mm or 1.5 mm) should be selected for such tight lesions, it is unknown whether a 1.25-mm burr or 1.5-mm burr is safer as the initial burr. The aim of this study was to compare the incidence of complications with a 1.25-mm versus a 1.5-mm burr as the initial burr for IVUS-uncrossable lesions. This was a retrospective, single-center study. A total of 109 IVUS-uncrossable lesions were included, and were divided into a 1.25-mm group (n =52) and a 1.5-mm group (n =57). The incidence of slow flow just after RA was not different between the 2 groups (1.25-mm group: 25%, 1.5-mm group: 31.6%, P =0.45). The incidence of peri-procedural MI with slow flow was not different and equally low in the 2 groups (1.25-mm group: 1.9%, 1.5-mm group: 3.5%, P =0.61). The use of the 1.5-mm burr as the initial burr was not significantly associated with slow flow after controlling for chronic renal failure on hemodialysis and reference diameter (vs. 1.25-mm: OR 2.34, 95% CI 0.89-6.19, P =0.09). In conclusion, the incidence of complications following RA was comparable between the 1.25-mm and the 1.5-mm burrs as the initial burr for IVUS-uncrossable lesions. The present study provides insights into the selection of an appropriate burr for IVUS-uncrossable lesions.

Halfway rotational atherectomy for calcified lesions: Comparison with conventional rotational atherectomy in a propensity-score matched analysis

Background

The incidence of severe complications such as burr entrapment or perforation is considerable with rotational atherectomy (RA). Halfway RA is a novel strategy, in which an operator does not advance the burr to the end of a continuous calcified lesion, and performs balloon dilatation to treat the remaining part of the calcified lesion. The purpose of this study was to compare complications after halfway and conventional RA.

Methods

We included 307 consecutive lesions that were divided into a conventional RA group (n = 244) and halfway RA group (n = 63). In analysis 1, the incidence of complications was compared between the conventional RA and halfway RA groups. Propensity-score matching was used to match the intentional halfway RA and conventional RA. In analysis 2, the incidence of complications was compared between the matched conventional RA and intentional halfway RA groups.

Results

Burr entrapment (0.4%) and major perforation (0.8%) were observed in the conventional RA group, whereas there was no burr entrapment or perforation in the halfway RA group. The success rate of halfway RA was 90.5%, which required switching from halfway RA to conventional RA. The incidences of slow flow and periprocedural myocardial infarction with slow flow were similar between the intentional halfway RA and matched conventional RA groups.

Conclusions

There was no burr entrapment or vessel perforation following halfway RA. The incidences of slow flow and periprocedural myocardial infarction were similar between the intentional halfway RA and the matched conventional RA, indicating the safety of halfway RA.

Association of Excessive Speed Reduction with Clinical Factors During Rotational Atherectomy

BACKGROUND

Although the manufacturer recommends that excessive speed reduction (>5000 rpm) be avoided during rotational atherectomy (RA) for safety, excessive speed reduction is sometimes observed in clinical practice. The purpose of the present study was to examine the factors associated with excessive speed reduction during RA.

METHODS

Lesions (n = 300) treated by RA were divided into 3 groups: a mild speed reduction group (≤5000 rpm) (n = 182), a moderate speed reduction group (>5000-≤10,000 rpm) (n = 97), and a severe speed reduction group (>10,000 rpm) (n = 21). Two multivariate logistic regression analyses was performed to investigate the factors associated with >5000 rpm speed reduction, and factors associated with >10,000 rpm speed reduction.

RESULTS

Multivariate logistic regression analysis revealed that an ostial right coronary artery (RCA) lesion (OR 6.13, 95% CI 1.82-20.70, P = 0.004) and total ablation time (every 10 s increase: OR 1.09, 95% CI 1.05-1.14, P < 0.001) were significantly associated with >5000 rpm speed reduction. An ostial RCA lesion (OR 14.17, 95% CI 3.85-52.23, P < 0.001), use of intra-aortic balloon pump support (OR 4.19, 95% CI 1.18-14.87, P = 0.03), and systolic blood pressure just before RA (every 10 mmHg increase: OR 1.25, 95% CI 1.02-1.52, P = 0.03) were significantly associated with >10,000 rpm speed reduction.

CONCLUSIONS

RA of ostial RCA lesions was significantly associated with excessive speed reduction during RA, which implies that RA of ostial RCA lesions is technically more difficult than RA of non-ostial RCA lesions.

Intentional switch between 1.5-mm and 1.25-mm burrs along with switch between rotawire floppy and extra-support for an uncrossable calcified coronary lesion

Rotational atherectomy (RA) is considered to be the last resort for a severely calcified coronary artery lesion. Severe complications such as vessel perforation or burr entrapment is closely associated with forceful burr manipulation during RA. The instructions for use of Rotablator (Boston Scientific, Marlborough, MA, USA) prohibit forceful burr manipulation when rotational resistance occurs. Nevertheless, RA operators tend to forcefully manipulate the burr if it cannot cross the lesion, because there has been no established strategy for an uncrossable lesion. We present a case with a severely calcified coronary lesion, which was uncrossable by a burr 1.5 mm with RotaWire Floppy (Boston Scientific). We intentionally switched 2 burrs (1.5-mm and 1.25-mm) and 2 RotaWires (Floppy and Extra-support) to cross the lesion. Uniquely, we downsized the burr (from 1.5-mm to 1.25-mm) initially for better penetration force, and upsized the burr (from 1.25-mm to 1.5-mm) finally for better contact to the calcification within the lesion. Our case suggests that 4 different types of combinations might work in a mutually complementary manner for an uncrossable calcified lesion.

<Learning Objective: In rotational atherectomy, severe complications such as vessel perforation or burr entrapment are closely associated with forceful burr manipulation. We present a case with a severely calcified coronary lesion, which was uncrossable by a burr 1.5 mm with RotaWire Floppy. We intentionally switched 2 burrs and 2 RotaWires to cross the lesion. Our case suggests that 4 different types of combinations might work in a mutually complementary manner for an uncrossable calcified lesion.>

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.

Intravascular ultrasound enhances the safety of rotational atherectomy

Intravascular ultrasound (IVUS) is mainly used in PCI to treat complex lesions, such as left main bifurcation, chronic total occlusion and calcified lesions. Although IVUS yields useful information such as the presence of napkin-ring calcification, the role of IVUS in rotational atherectomy (RA) is not fully appreciated. Recently, since the deliverability and crossability of IVUS catheters have improved, IVUS should be attempted before RA. Even if the IVUS catheter cannot cross the lesion, IVUS provides information just proximal to the target lesion, which would be useful in the selection of the appropriate guidewire and burr size. IVUS can be repeated following RA, which may influence the decision to continue RA with larger burrs. Circumferential calcification is a good indication for RA, since RA can create a calcium crack that facilitates balloon dilatation. However, if the distribution of calcification is not circumferential, the indication for RA can more safely be determined based on IVUS images than angiographic information alone. Because RA burrs usually follow the route taken by the IVUS catheter, the positional relationship between the IVUS imaging core and calcification would be similar to that between the RA burrs and calcification. The relationship between the RA burrs and distribution of calcification is discussed in this review.

When a Burr Can Not Penetrate the Calcified Lesion, Increasing Burr Size as Well as Decreasing Burr Size Can Be a Solution in Rotational Atherectomy

In rotational atherectomy (RA), several burr sizes are available, such as 1.25 mm, 1.5 mm, 1.75 mm, or ≥ 2.0 mm. It is important to select an appropriate burr size for each lesion because rotational atherectomy has several unique complications regarding burrs such as entrapment or perforation. When a burr cannot penetrate the lesion, downsizing of the burr is generally recommended. Also, if the smallest burr (1.25 mm) cannot penetrate the lesion, a change to a more supportive or larger French guiding catheter has been recommended. We describe the case of a 68 year-old female who was referred to our department for percutaneous coronary intervention to the calcified stenosis in the middle of the left anterior descending coronary artery. We used the smallest burr (1.25 mm) and a supportive 7 Fr guiding catheter to penetrate the lesion. However, the smallest burr could not pass the lesion even after 14 sessions (total ablation time: 339 seconds). We intentionally increased the burr size from 1.25 mm to 1.5 mm. The 1.5 mm burr successfully passed the lesion without any perforation or burr entrapment. In this manuscript, we discuss why increasing the burr size was successful for this severely calcified lesion that was not penetrated by the smallest burr.

Incidence and Determinants of Complications in Rotational Atherectomy

Background—

The usage of rotational atherectomy (RA) is growing in the current percutaneous coronary intervention (PCI) because of the expansion of PCI indication to more complex lesions. However, the complications after RA have been linked to procedure-related morbidity and mortality. The purpose of this study was to investigate the incidence and determinants of complications in RA using a large nationwide registration system in Japan (J-PCI).

Methods and Results—

The primary composite outcome of this study was defined as the occurrence of in-hospital death, cardiac tamponade, and emergent surgery after RA. A total of 13 335 RA cases (3.2% of registered PCI cases) were analyzed. The composite outcome was observed in 175 cases (1.31%) and included 80 in-hospital deaths (0.60%), 86 tamponades (0.64%), and 24 emergent surgeries (0.18%). The clinical variables associated with occurrence of the composite outcome were age (odds ratio [OR] 1.03 per unit increment, 95% confidence interval [CI] 1.02–1.05), impaired kidney function (OR 1.59, 95% CI 1.15–2.19), previous myocardial infarction (OR 1.69, 95% CI 1.21–2.35), emergent PCI (OR 4.02, 95% CI 1.66–8.27), and triple-vessel disease (versus single-vessel disease: OR 2.17, 95% CI 1.43–3.28). Notably, institutional volume of RA cases was inversely associated with the composite outcomes (high- versus low-volume institution: OR 0.56, 95% CI 0.36–0.89).

Conclusions—

The reported incidence of important procedure-related complication rate was 1.3%, with each component ranging between 0.2% and 0.6% in J-PCI. Its determinants were both patient related (age, impaired kidney function, and previous myocardial infarction) and procedure related (emergent procedures, number of diseased vessels, and institutional volume of RA).

Comparison of mid-term clinical outcomes between on-label and off-label use of rotational atherectomy

While rotational atherectomy (RA) is used for complex lesions in percutaneous coronary intervention, there are several contraindications such as unprotected left main stenosis or left ventricular dysfunction. We previously reported that the incidence of in-hospital complications was significantly greater in off-label as compared to on-label use RA. However, the mid-term clinical outcomes between off-label and on-label RA have not been investigated. The purpose of this study was to compare the mid-term clinical outcomes between off-label (n = 156) and on-label RA (n = 94). The primary endpoint was the incidence of major adverse cardiovascular events (MACE) defined as the composite of ischemia-driven target vessel revascularization (TVR), non-fatal MI, and all-cause death. We also identified 154 patients who underwent RA and follow-up angiography within 1 year, and compared quantitative coronary analysis between the off-label group (n = 96) and on-label group (n = 58). There was no significant difference in late luminal loss between the groups (0.03 ± 0.53 mm in the off-label and -0.05 ± 0.44 mm in the on-label groups, P = 0.57). However, the incidence of MACE was less in the on-label group (3.2 %) as compared to the off-label group (9.0 %) without reaching statistical significance (P = 0.08). In conclusion, mid-term clinical outcomes tended to be worse in the off-label group than in the on-label group. We may have to follow-up the patient who underwent off-label RA more carefully than the patient who underwent on-label RA.

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.

How Should We Perform Rotational Atherectomy to an Angulated Calcified Lesion?

Rotational atherectomy to an angulated calcified lesion is always challenging. The risk of catastrophic complications such as a burr becoming stuck or vessel perforation is greater when the calcified lesion is angulated. We describe the case of an 83-year-old female suffering from unstable angina. Diagnostic coronary angiography revealed an angulated calcified lesion in the proximal segment of the right coronary artery. We performed rotational atherectomy to the lesion, but intentionally did not advance the rotational atherectomy burr beyond the top of the angulation. We controlled the rotational atherectomy burr and stopped it just before the top of the angulation to avoid complications. Following rotational atherectomy, balloon dilatation with a non-compliant balloon was performed, and drug-eluting stents were successfully deployed. In this manuscript, we provide a review of the literature on this topic, and discuss how rotational atherectomy to an angulated calcified lesion should be performed.

Successful retrieval of a firmly stuck rotablator burr by using a modified STAR technique

Rotablator burr entrapment occurring during rotational atherectomy is a rare but serious complication that can lead to coronary occlusion and require emergency cardiac surgery. Although several bailout techniques for stuck burrs have been proposed, no definitive methods for removal have been established. We report here a difficult case of a stuck rotablator burr, in which various techniques failed to retrieve the burr. It was ultimately removed using the subintimal tracking and reentry (STAR) technique with a 3-g tapered tip hydrophilic wire. This modified STAR technique, which was originally developed for percutaneous coronary intervention for chronic total occlusion, may be useful as a bailout technique in patients with a firmly stuck rotablator burr that cannot be removed by using standard procedures.

Mechanism and management of burr entrapment: A nightmare of interventional cardiologists

Entrapment of the burr within calcified lesion is an uncommon, but serious complication during rotational atherectomy and usually needs surgical retrieval. We report a case series of this complication and also review the possible mechanisms, such as kokesi phenomenon or insufficient pecking motion with decreased rotational speed. We also review the potential techniques ever proposed to rescue this complication percutaneously, including simple manual traction, balloon dilation to release the trap, snaring the burr as distal as possible for forceful local traction and wedging the burr with a child catheter to facilitate retrieval. Gentle pecking motion of the burr for sufficient ablation and shortening the run less than 15 s may avoid such complications. Interventional cardiologists using the rotablator should be familiar with the tips and tricks to avoid and rescue this complication.

[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.