Rotational atherectomy: Technical update

Prediction of the debulking effect of rotational atherectomy using optical frequency domain imaging: a prospective study

This study determined the predictive accuracy of optical frequency domain imaging (OFDI) on debulking effects of rotational atherectomy (RA) and compared the predictive accuracy of OFDI catheter-based with Rota wire-based prediction methods. This prospective, single-center, observational study included 55 consecutive patients who underwent OFDI-guided RA. On pre-RA OFDI images, a circle, identical to the Rota burr was drawn at the center of the OFDI catheter (OFDI catheter-based prediction method) or wire (wire-based prediction method). The area overlapping the vessel wall was defined as the predicted ablation area (P-area). The actual ablated area (A-area) was measured by superimposing the OFDI images before and after RA. The overlapping P-area and A-area were defined as overlapped ablation area (O-area), and the predictive accuracy was evaluated by %Correct area (O-area/P-area) and %Error area (A-area  - O-area/A-area). The median %Correct and %Error areas were 47.8% and 41.6%, respectively. Irrelevant ablation (low %Correct-/high % Error areas) and over ablation (high %Correct-/high % Error areas) were related to deep vessel injury and intimal flap outside the P-area. The predictive accuracy was better in the OFDI catheter-based prediction method than the wire-based prediction method in the cross sections where the OFDI catheter and wire came in contact. However, it was better in the latter than the former where the OFDI catheter and wire were not in contact. OFDI-based simulation of the RA effect is feasible though accuracy may be affected by the OFDI catheter and wire position. OFDI-based simulation of RA effect might reduce peri-procedural complications during RA.

Utility of the SYNTAX Score in the risk stratification of patients undergoing rotational atherectomy

Introduction

The SYNTAX Score (SS) evaluates the angiographic complexity of coronary artery disease to assess the cardiovascular risk after coronary revascularization. The aim of the study was to evaluate whether SS results are associated with in-hospital and 1-year outcomes of patients undergoing percutaneous coronary intervention (PCI) requiring rotational atherectomy (RA).

Material and methods

We analyzed data of 207 consecutive patients who underwent PCI with RA. Patients were divided into two groups: those with high SS (> 33 points) and those with low/intermediate SS (0–33 points).

Results

In 21 (10%) patients SS was high and 186 (90%) patients had low/intermediate SS. Patients with high SS were older (76 vs. 71 years, p = 0.008) and more frequently diagnosed with chronic kidney disease (38% vs. 18%, p = 0.03) and heart failure (71% vs. 30%, p = 0.0001). In patients with high SS the RA procedure was longer (p = 0.004), required more contrast (p = 0.005) and higher radiation doses (p = 0.04), and contrast-induced nephropathy was more frequent (14% vs. 2%, p = 0.001).

Conclusions

In our RA patients there was no significant difference between the frequency of in-hospital and 1-year adverse cardiovascular events depending on the SS result. High SS correlates only with parameters describing the extensity and technical complexity of the procedure. However, the unavailability of other risk assessment tools in this population raises the need to create a new more specific risk score for patients requiring RA.

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.

Percutaneous coronary intervention of severely/moderately calcified coronary lesions using single-burr rotational atherectomy: A retrospective study

OBJECTIVE

This study evaluates the safety and efficacy of percutaneous coronary intervention in moderately and severely calcified coronary lesions, which are either not crossed or dilated using a Scoreflex balloon at nominal pressure, using single-burr rotational atherectomy (burr-artery ratio, ≤0.6) followed by scoring balloon dilatation (balloon-artery ratio, 0.9).

METHODS

We retrospectively identified 144 patients with severely and moderately calcified native coronary lesions, which were either not crossed or fully opened using an appropriately sized Scoreflex balloon at nominal pressure, from a tertiary care center in India. All patients underwent rotational atherectomy. The primary endpoint was angiographic and procedural success and in-hospital clinical outcomes. The secondary endpoint was the incidence of major adverse cardiac events (MACE) at one-year clinical follow-up.

RESULTS

The mean age of the patients was 68.75±8.37 years, and 83.33% of them were over 60 years old. Moderate calcification was present in 21.53%, and the remaining 78.47% had severe calcification. Procedural success was achieved in 139 (96.52%) patients. In-hospital death was reported in four (2.77%) patients. Multiple regression analysis revealed that in severely calcified coronary lesions, burr rotation speed and heparin dose were significantly associated with in-hospital MACE occurrence (p=0.0337).

CONCLUSION

A modified small-burr rotational atherectomy technique with scoring balloon angioplasty pre-dilatation is a safe and effective surgical procedure with favorable clinical outcomes for moderately and severely calcified coronary lesions.

A New Era for Rotational Atherectomy: An Australian Perspective

Background:

Rotational atherectomy (RA) has been used in percutaneous coronary intervention (PCI) for 30 years. With advances in technology, this observational study looks at how rates of RA have changed over the past decade in Australia in relation to PCI and coronary artery bypass graft (CABG) rates.

Methods:

Retrospective analysis of RA, PCI, and CABG rates per Australian state from Australian Government Department of Human Services’ data on Medicare items from 2007 to 2017 was carried out.

Results:

There were 149 RA procedures in 2007, increasing to 452 in 2017. Rotational atherectomy accounted for 0.67% of PCI procedures in 2007, increasing to 1.48% in 2018 (+0.81%, 95% confidence interval [CI] = [0.64%-0.91%]; P < .001). Most of this increase has come from procedures in New South Wales (441% increase). Australian PCI rate increased from 22 301 to 30 480. Rate of CABG decreased from 5418 to 5206.

Conclusions:

From 2007 to 2017, rates of RA trebled in Australia. This is despite stable rates of PCI and a fall in rates of CABG. There are several clinical explanations for this trend.

Computational Fluid Dynamics Modeling of the Burr Orbital Motion in Rotational Atherectomy with Particle Image Velocimetry Validation

Rotational atherectomy (RA) uses a high-speed rotating burr introduced via a catheter through the artery to remove hardened atherosclerotic plaque. Current clinical RA technique lacks consensus on burr size and rotational speed. The rotating burr orbits inside the artery due to the fluid force of the blood. Different from a common RA technique of upsizing burrs for larger luminal gain, a small burr can orbit to treat a large lumen. A 3D computational fluid dynamics (CFD) model was developed to simulate the burr motion and study the fluid flow and force in RA. A particle image velocimetry experiment was conducted to measure and validate the flow field including the radial and axial velocities and a pair of counter-rotating vortices near the burr equator in CFD. The hydraulic force on the burr and the contact force between the burr and the arterial wall were estimated by CFD. The contact force can be reduced by using smaller burr and lower rotational speed. Utilizing the small burr orbital motion has the potential to be an improved RA technique.

Very Long-Term Follow-Up After Coronary Rotational Atherectomy: A Single-Center Experience

We assessed the very long-term follow-up of a large cohort of unselected patients treated with coronary rotational atherectomy (RA). All 143 patients who underwent RA at our institution from 2000 to 2013 and with complete baseline and follow-up information were analyzed in a retrospective manner. Major adverse cardiac events (MACE) were defined as the composite of target vessel revascularization (TVR), acute myocardial infarction, and all-cause mortality. The mean follow-up was 8.2 years. The 10-year cumulative incidence of MACE for all patients was 57.9% (standard error [SE]: 5.0%). When comparing patients who received a drug-eluting stent (DES; n = 68) versus patients who did not (balloon only, bare-metal stent, or none of the aforementioned; n = 75), the RA + DES demonstrated very long-term MACE of 49.2% (SE: 7.5%) versus 62.7% (SE: 6.1%), P = .160 with TVR as the most discriminating factor, 10.7% (SE: 4.0%) versus 29.2% (SE: 6.0%), P = .016. Our results point to RA having reasonable long-term clinical results, especially in combined treatment with DES. To date, our study has the longest follow-up after RA.

Intensive plaque modification with rotational atherectomy and cutting balloon before drug-eluting stent implantation for patients with severely calcified coronary lesions: a pilot clinical study

BACKGROUND

This study investigated whether, for patients with severely calcified coronary lesions, use of a cutting balloon (CB) during rotational atherectomy (RA) before placing a drug-eluting stent will improve periprocedural outcomes, compared to RA with a conventional plain balloon.

METHODS

In a randomized controlled trial, patients with severely calcified lesions of calcium arc ≥180° were apportioned to receive intensive plaque modification with RA and CB (RA + CB; n = 35) or RA with conventional plain balloon (RA; n = 36). Intravascular ultrasound was applied for quantitative or qualitative analyses of percutaneous coronary intervention outcomes. The primary outcome was acute lumen gain after drug-eluting stent.

RESULTS

The RA + CB and RA groups were similar in baseline mean arcs of superficial calcium, and minimum lumen cross-sectional areas (CSAs). The mean minimum stent CSA after percutaneous coronary intervention (PCI) of the RA + CB group (5.9 ± 1.7 mm(2)) was significantly larger than that of the RA group (5.0 ± 1.4 mm(2); P = 0.021). Patients in the RA + CB group achieved significantly larger acute CSA gain after PCI (4.5 ± 1.5 mm(2)) relative to the RA group (3.8 ± 1.5 mm(2); P = 0.035). The groups were similar in rates of periprocedural complications, but at the 1-year follow-up the RA + CB had a lower rate of revascularization for restenosis of the target vessel and MACE (5.7 %) than did the RA group (22.2 %, P = 0.046).

CONCLUSION

Aggressive plaque preparation with RA and CB seems to be safe and effective for patients with severely calcified coronary lesions.

TRIAL REGISTRATION

Current Controlled Trials ChiCTR-INR-16008274 . Retrospectively registered 12 April 2016.