Atherectomy Devices for the Treatment of Calcified Coronary Lesions

ShOckwave ballooN or Atherectomy with Rotablation in calcified coronary artery lesions: Design and rationale of the SONAR trial

BACKGROUND

The percutaneous treatment of calcified coronary lesions remains challenging and is associated with worse clinical outcomes. In addition, coronary artery calcification is associated with more frequent peri-procedural myocardial infarction.

STUDY DESIGN AND OBJECTIVES

The ShOckwave ballooN or Atherectomy with Rotablation in calcified coronary artery lesions (SONAR) study is an investigator-initiated, prospective, randomized, international, multicenter, open label trial (NCT05208749) comparing a lesion preparation strategy with either shockwave intravascular lithotripsy (IVL) or rotational atherectomy (RA) before drug-eluting stent implantation in 170 patients with moderate to severe calcified coronary lesions. The primary endpoint is difference in the rate of peri-procedural myocardial infarction. Key secondary endpoints include rate of peri-procedural microvascular dysfunction, peri-procedural myocardial injury, descriptive study of IMR measurements in calcified lesions, technical and procedural success, interaction between OCT calcium score and primary endpoint, 30-day and 1-year major adverse clinical events.

CONCLUSIONS

The SONAR trial is the first randomized controlled trial comparing the incidence of peri-procedural myocardial infarction between 2 contemporary calcium modification strategies (Shockwave IVL and RA) in patients with calcified coronary artery lesions. Furthermore, for the first time, the incidence of peri-procedural microvascular dysfunction after Shockwave IVL and RA will be evaluated and compared.

Systematic Review of the Efficacy of Orbital Atherectomy in Improving the Outcome of Percutaneous Corornary Intervention in People With Diabetes

The optimal approach to deal with severe coronary artery calcification (CAC) in people with diabetes remains ill-defined. People with diabetes have a significant risk of developing severe vessel calcification and coronary artery disease (CAD). CAD is the leading cause of death in people with diabetes. Individuals with diabetes mainly present with severe multivessel stenosis, diffuse coronary calcification, and severe atherosclerosis, which are poor prognostic factors of revascularization procedures. Studies have shown that the revascularization of arteries in people with diabetes often results in worse outcomes than in people without diabetes. Coronary artery bypass grafting (CABG) has been recommended as the standard of care for people with DM and complex anatomic diseases, including left main CAD. However, percutaneous coronary intervention (PCI) is more acceptable to patients in clinical practice because of decreased trauma and rapid recovery. Severe CAC has traditionally been challenging for PCI and a frequent indication for surgical revascularization. This study aims to determine the effectiveness of orbital atherectomy (OA) in improving PCI outcomes in patients with diabetes and identify possible adverse effects that preclude its use.  The study is reported according to PRISMA and analyzed according to Cochrane guidelines on synthesis without meta-analysis. A comprehensive literature search of EMBASE, Scopus, Web of Science, Cochrane Library, CINAHL, and MEDLINE was conducted for studies that utilized OA before PCI in people with diabetes. A reference list of the eligible articles was also screened. A narrative synthesis was done by representing the data on the effect direction plot, followed by vote counting. Eighteen studies were included in the analysis. Success rate/successful stent delivery was >90%, while freedom from angiographic complication and major adverse cardiovascular and cerebrovascular events (MACCE) were both >80% on the effect direction plot for people with diabetes and those without diabetes. People with diabetes had low event rates similar to those without diabetes. OA appears to be a viable treatment approach for people with diabetes. However, RCTs with a longer duration of follow-up are required to establish the appropriate treatment strategy for severe CAC in people with diabetes.

Clinical Outcomes of Different Calcified Culprit Plaques in Patients with Acute Coronary Syndrome

Background: Previous studies have found that coronary artery calcification is closely associated with the occurrence of major adverse cardiac events (MACE). This study aimed to investigate the characteristics and clinical outcomes of different calcified plaques in patients with acute coronary syndrome (ACS) by using optical coherence tomography (OCT). Methods: 258 ACS patients with calcified culprit plaques who underwent OCT-guided stent implantation were enrolled. They were divided into three subtypes based on the calcified plaque morphology, including eruptive calcified nodules, calcified protrusion, and superficial calcific sheet. Results: Compared with superficial calcific sheet and calcified protrusion, eruptive calcified nodules had the greatest calcium burden and a higher rate of stent edge dissection (p < 0.001) and incomplete stent apposition (p < 0.001). In a median follow-up period of 2 years, 39 (15.1%) patients experienced MACE (a composite event of cardiac death, target-vessel myocardial infarction, ischemia-driven revascularization), with a significantly higher incidence in the eruptive calcified nodules group (32.1% vs. 10.1% vs. 13.0%, p = 0.001). A multivariate Cox analysis demonstrated that the eruptive calcified nodules (hazard ratio 3.14; 95% confidence interval, 1.64−6.02; p = 0.001) were an independent predictor of MACE. Conclusions: MACE occurred more frequently in ACS patients with eruptive calcified nodules, and the eruptive calcified nodules were an independent predictor of MACE.

Optical coherence tomography: fundamentals and clinical utility

Although coronary angiography is the standard method employed to assess the severity of coronary artery disease and to guide treatment strategies, it provides only 2D image of the intravascular lesions. In contrast, intravascular imaging modalities such as optical coherence tomography (OCT) produce cross-sectional images of the coronary arteries at a far greater spatial resolution, capable of accurately determining vessel size as well as plaque morphology, eliminating many of the disadvantages inherent to angiography. This review will discuss the role of OCT in the catherization laboratory for the assessment and management of coronary disease.

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.

Plaque modification of severely calcified coronary lesions via orbital atherectomy: Single-center observations from a complex Veterans Affairs cohort

BACKGROUND

Orbital atherectomy (OA) is a known alternative to other atherectomy devices. However, some complex patient demographics (eg, left ventricular ejection fraction <25%) were excluded from the first-in-human trial (ORBIT I) and the pivotal FDA device approval trial (ORBIT II) which evaluated the safety and efficacy of OA in severely calcified de novo coronary lesions. This single-operator cohort study aimed to examine the impact of OA on a real-world complex Veterans Affairs patient subset.

METHODS

Retrospective analysis was completed on 40 consecutive patients with severely calcified coronary lesions who underwent OA prior to drug-eluting stent placement at the Atlanta Veterans Affairs Medical Center from January 2015 to June 2017.

RESULTS

Orbital atherectomy plus drug-eluting stent placement was successful in all 40 cases. Chocolate focal force balloon angioplasty was the most commonly used post-atherectomy balloon (N = 34, 85%). Few complications were observed, including one case (2.5%) of perforation and one case (2.5%) of no-reflow. Neither acute stent thrombosis nor emergent coronary artery bypass grafting was observed. The intravascular ultrasound (IVUS)-determined median [IQR] pre-procedure minimum lumen area and post-procedure minimum stent area (MSA) were 2.8 [2.2, 3.0] mm2 and 8.7 [7.7, 10.0] mm2, respectively (P < 0.0001, Mann-Whitney test). Major adverse cardiovascular events, including all-cause mortality, at 30 days and at a median [IQR] follow-up of 197.5 [35.5, 461.3] days, was 5% and 10%, respectively. During that period, one target vessel revascularization (2.5%) was observed.

CONCLUSIONS

This study indicates that OA is a useful tool in performing high-risk percutaneous coronary intervention effectively in VA patients with severely calcified coronary lesions. OA plaque modification in combination with a high utilization rate of IVUS and Chocolate focal force angioplasty facilitates stent delivery and optimal stent expansion, resulting in a large MSA.

Percutaneous Left Main Coronary Intervention: A Review of Plaque Modification in Left Main Percutaneous Coronary Intervention

Left main coronary artery (LMCA) stenosis has long been recognized as a marker of increased morbidity and mortality. Current treatment algorithms for LMCA stenosis consider both percutaneous coronary intervention (PCI) with drug eluting stents (DES) and coronary bypass surgery, each with advantages based on individual patient characteristics. Since the LMCA is the largest artery in the coronary tree, plaque volume and calcification is greater than other coronary segments and often extends to the distal bifurcation segment. In LMCA bifurcation lesions, larger minimal stent area is strongly associated with better outcome in the DES era. Plaque modification strategies such as rotational, orbital, or laser atherectomy are effective mechanisms to reduce plaque volume and alter compliance, facilitating stent delivery and stent expansion. We present a case of a calcified, medina class 1,1,1 LMCA lesion where intravascular ultrasound (IVUS) and orbital atherectomy were employed for optimal results. In this context, we review the evidence of plaque modification devices and the rationale for their use in unprotected left main PCI.