Effectiveness and safety of a novel intravascular lithotripsy system for severe coronary calcification: CALCI-CRACK trial

BACKGROUND

Intravascular lithotripsy is effective and safe for managing coronary calcification; however, available devices are limited, and complex lesions have been excluded in previous studies. This study aimed to investigate the effectiveness and safety of a novel intravascular lithotripsy system for severe calcification in a population with complex lesions.

METHODS

CALCI-CRACK (ChiCTR2100052058) is a prospective, single-arm, multicenter study. The primary endpoint was the procedural success rate. Major safety endpoints included major adverse cardiovascular events (MACE) and target lesion failure (TLF) at 30 days and 6 months, and severe angiographic complications. Calcification morphology was assessed in the optical coherence tomography (OCT) subgroup.

RESULTS

In total, 242 patients from 15 high-volume Chinese centers were enrolled, including 26.45% of patients with true bifurcation lesions, 3.31% with severely tortuous vessels, and 2.48% with chronic total occlusion, respectively. The procedural success rate was 95.04% (95% confidence interval 91.50-97.41%), exceeding the pre-specified performance goal of 83.4% (p<0.001). The 30-day and 6-month MACE rates were 4.13% and 4.55%, respectively. TLF rates at these time-points were 1.24% and 1.65%, respectively. Severe angiographic complications occurred in 0.42% of patients. In the OCT subgroup (n=93), 93.55% of calcified lesions were fractured, and minimal lumen area increased from 1.55 ± 0.55 mm2 to 4.91 ± 1.22 mm2 after stent implantation, with acute gain rate of 245 ± 102%.

CONCLUSIONS

The novel intravascular lithotripsy system is effective and safe for managing severely calcified coronary lesions in a cohort that included true bifurcation lesions, severely tortuous vessels, and chronic total occlusion. (ChiCTR2100052058).

Direct Comparison of Rotational vs Orbital Atherectomy for Calcified Lesions Guided by Optical Coherence Tomography

BACKGROUND

There are several retrospective studies comparing rotational atherectomy (RA) and orbital atherectomy (OA), but all percutaneous coronary interventions (PCIs) in those studies were not performed under intracoronary imaging guidance.

OBJECTIVES

This study sought to compare the efficacy and safety of optical coherence tomography (OCT)-guided PCI with RA vs OA.

METHODS

The DIRO (To directly compare RA and OA for calcified lesions, a prospective randomized trial) trial was conducted. We enrolled patients with de novo calcified lesions (arc >180°) assessed by OCT or angiographically moderate or severe calcifications if the OCT catheter could not cross the lesion before any intervention. Eligible patients were randomly 1:1 allocated to lesion preparation with RA vs OA. Stent expansion was defined as the minimum stent area divided by the distal reference area multiplied by 100. Tissue modification was assessed using preatherectomy and postatherectomy OCT images. Procedural outcomes including periprocedural myocardial infarctions were evaluated. Furthermore, clinical events and vascular healing evaluated by OCT at 8 months postprocedure were assessed.

RESULTS

The stent expansion was significantly greater in the RA group vs the OA group (99.5% vs 90.6%; P = 0.02). The maximum atherectomy area was significantly larger in the RA group than in the OA group (1.34 [IQR: 1.02-1.89] mm2 vs 0.83 [IQR: 0.59-1.11] mm2; P = 0.004). The procedural outcomes and clinical events at 8 months did not differ between the groups. The vascular healing was sufficient in both groups.

CONCLUSIONS

The prospective randomized DIRO trial revealed that RA could produce a more favorable tissue modification, which may lead to a larger stent expansion than OA in heavily calcified lesions.

Contemporary percutaneous management of coronary calcification: current status and future directions

Severe coronary artery calcification is one of the greatest challenges in attaining success in percutaneous coronary intervention, limiting acute and long-term results. In many cases, plaque preparation is a critical prerequisite for delivery of devices across calcific stenoses and also to achieve adequate luminal dimensions. Recent advances in intracoronary imaging and adjunctive technologies now allow the operator to select the most appropriate strategy in each individual case. In this review, we will revisit the distinct advantages of a complete assessment of coronary artery calcification with imaging and application of appropriate and contemporary plaque modification technologies in achieving durable results in this complex lesion subset.

Coronary orbital atherectomy using a five-French guiding catheter

Recently, the efficacy was demonstrated of the Diamondback 360® Coronary Orbital Atherectomy System (OAS) (Cardiovascular Systems, Inc., St. Paul, MN, USA) for treating calcified coronary lesions in percutaneous coronary intervention (PCI). The safety and feasibility of OAS application through a 5-Fr guiding catheter (GC) which is less invasive and reduces access site complications were validated. This sequential, retrospective, observational study was conducted in a single center from September 2018 to May 2020. The primary endpoint was a successful PCI with the OAS. Secondary endpoints were major adverse complications related to PCI with the OAS, including coronary dissection, perforation, side branch loss, need for an unexpected cardiac assist device, access site complications, and major adverse cardiac and cerebrovascular events. 33 PCIs in 30 patients (mean age 72 ± 11 years; male, 83.3%) were surveyed. All PCIs were successfully completed with OAS application through a 5-Fr GC. Coronary perforation after the OAS procedure occurred in one case (3.0%). Severe coronary dissection occurred in three cases (9.1%), and procedural myocardial infarction in two cases (6.1%). Regarding PCIs performed with the 5-Fr GC, the OAS is a safe and feasible strategy for calcified plaque modification.

Intravascular shockwave lithotripsy as a treatment modality for symptomatic mesenteric ischemia

Chronic mesenteric ischemia has traditionally been treated with either open surgical revascularization or endovascular therapy. Endovascular surgery has typically been preferred due to the lower rates of peri-procedural and post-procedural morbidity, yet this comes at the expense of long-term durability. Intravascular shockwave lithotripsy is a technique utilized to modify intimal and medial calcified plaque in order to improve vessel expansion and patency. Intravascular lithotripsy has been investigated as both primary and adjunctive treatment for peripheral arterial and coronary arterial lesions, however, its use in the treatment of chronic mesenteric ischemia requires further investigation. We present a case of a 75-year-old woman with symptomatic mesenteric ischemia who underwent intravascular shockwave lithotripsy of a 99% stenosis superior mesenteric artery with an excellent outcome.

Safety and effectiveness of coronary intravascular lithotripsy in eccentric calcified coronary lesions: a patient-level pooled analysis from the Disrupt CAD I and CAD II Studies

BACKGROUND

The aim of this study was to assess the safety and effectiveness of intravascular lithotripsy (IVL) in treating eccentric calcified coronary lesions.

METHODS

Between December 2015 and March 2019, 180 patients were enrolled in the Disrupt CAD I and CAD II studies across 19 sites in 10 countries. Patient-level data were pooled from these two studies (n = 180), within which 47 eccentric lesions (26%) and 133 concentric lesions were identified.

RESULTS

Clinical success, defined as residual stenosis < 50% after stenting and no in-hospital MACE, was similar between the eccentric and concentric cohorts (93.6% vs. 93.2%, p = 1.0). There were no perforations, abrupt closure, slow flow or no reflow events observed in either group, and there were low rates of flow-limiting dissections (Grade D-F: 0% eccentric, 1.7% concentric; p = 0.54). Final acute gain and percent residual stenosis were similar between the two groups. Final residual stenosis of 8.6 ± 9.8% in eccentric and 10.0 ± 9.0% (p = 0.56) in concentric stenosis confirms the significant effect of IVL in calcified coronary lesions.

CONCLUSION

In this first report from a pooled patient-level analysis of coronary IVL from the Disrupt CAD I and CAD II studies, IVL use was associated with consistent improvement in procedural and clinical outcomes in both eccentric and concentric calcified lesions.

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.

Management of Calcific Coronary Artery Lesions: Is it Time to Change Our Interventional Therapeutic Approach?

Patients with obstructive coronary lesions with a high calcium content (LHCC) have an exaggerated clinical risk, because the presence of calcification is associated with more extensive coronary atheroma and higher burden of comorbidities. Treatment of LHCC using percutaneous techniques is complex because of an increased risk of incomplete lesion preparation with suboptimal stent deployment and higher rates of acute and chronic stent failure. Rotational atherectomy has been the predominant technology for treatment of high-grade LHCC, but novel devices/technologies have entered clinical practice. It seems likely that combining enhanced intravascular imaging, which allows definition of the patterns of calcification with these new technologies, will herald a change in procedural algorithms for treatment of LHCC. This review provides an overview about LHCC with special focus on existing and emergent technologies. We also provide a proposed procedural algorithm to facilitate optimal use of technology according to specific features of LHCC and coronary anatomy.

Percutaneous endovascular delivery of calcium chloride to the intact porcine carotid artery: A novel animal model of arterial calcification

OBJECTIVE

The present study evaluated the effect of endovascular administration of calcium chloride to the carotid artery of swines, to create a model of arterial calcification.

METHODS

Fifteen Large White pigs were used for the study. Via endovascular treatment, carotid arteries were exposed during 9 min to either calcium chloride (experimental artery) or saline (control artery) with the use of the TAPAS catheter. Intravascular ultrasound (IVUS) imaging was obtained at baseline, postprocedure and at 30 days. Optical coherence tomography (OCT) imaging was obtained in vitro after carotids were harvested. Longitudinally cut parallel arterial segments were placed in a system of delicate clamps and underwent uniaxial strain test. All arteries underwent histopathological examination.

RESULTS

Calcium chloride treated segments showed extensive circumferential parietal calcification evident on both IVUS and OCT. Reduction in minimal lumen area on IVUS was evident in experimental arteries both at 24 hr and 30 days postprocedure. Histopathologic assessment (Von Kossa stain) confirmed medial calcification with mild intimal thickening. Biomechanical testing showed treated segments to have smaller breaking strength and less elastic deformation than controls.

CONCLUSION

We developed a nonexpensive, reproducible model of early carotid medial calcification in pigs. Our model has the potential to help the development of research to unravel mechanisms underlying arterial calcification, the use of current or new devices to treat calcified lesions as well as to serve as an option for training interventionalists on the use of such devices.

Lesion Preparation with Orbital Atherectomy

Despite significant improvements in stent design, severe coronary calcification continues to impede adequate stent expansion and is associated with worse clinical outcomes. Angiography is limited in its ability to detect and comprehensively characterise calcified plaque. Intravascular imaging provides information on lesion morphology guiding appropriate treatment strategies. Orbital atherectomy allows for lesion preparation of severely calcified plaque prior to stent implantation. Utilising a unique mechanism of action incorporating centrifugal forces, a standard 1.25 mm eccentrically mounted and diamond-coated burr orbits bi-directionally to ablate calcified plaque. Lesion preparation with orbital atherectomy allows for modification of calcified plaque to facilitate stent expansion.

Contemporary Approach to Heavily Calcified Coronary Lesions

Percutaneous treatment of heavily calcified coronary lesions still represents a challenge for interventional cardiology, with higher risk of immediate complications, late failure due to stent underexpansion and malapposition, and consequently poor clinical outcome. Good characterisation of calcium distribution with multimodal imaging is important to improve the successful treatment of these lesions. The use of traditional or new dedicated devices for the treatment of calcified lesions allows better lesion preparation; therefore, it is important that we know the different mechanisms and technical features of these devices.

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.

Orbital Atherectomy: A Comprehensive Review

Successful percutaneous coronary intervention (PCI) can be challenging in the presence of heavily calcified lesions. Severely calcified lesions are associated with worse clinical outcomes. Recognition of calcification is important before stenting to ensure adequate stent expansion can be attained. Orbital atherectomy is a safe and effective method to ablate calcified plaque. Lesion preparation through plaque modification with orbital atherectomy before stent implantation can help to optimize the results of PCI in these complex lesions.