One-Year Outcomes of Peripheral Endovascular Device Intervention in Critical Limb Ischemia Patients: Sub-Analysis of the LIBERTY 360 Study.

BACKGROUND: High-risk patients with advanced peripheral artery disease (PAD), including critical limb ischemia (CLI), are often excluded from peripheral endovascular device intervention clinical trials, leading to difficulty in translating trial results into real-world practice. There is a need for prospectively assessed studies to evaluate peripheral endovascular device intervention outcomes in CLI patients. METHODS: LIBERTY 360 is a prospective, observational, multi-center study designed to evaluate the procedural and long-term clinical outcomes of peripheral endovascular device intervention in real-world patients with symptomatic lower-extremity PAD. One thousand two hundred and four patients were enrolled and stratified based on Rutherford Classification (RC): RC2-3 (N=501), RC4-5 (N=603), and RC6 (N=100). For this sub-analysis, RC5 and RC6 patients (RC5-6; N=404) were pooled and 1-year outcomes were assessed. RESULTS: Procedural complications rarely (1.7%) resulted in post-procedural hospitalization and 89.1% of RC5-6 patients were discharged to home. Considering the advanced disease state in RC5-6 patients, there was a high freedom from 1-year major adverse event rate of 65.5% (defined as target vessel revascularization, death to 30 days, and major target limb amputation). At 1 year, freedom from major amputation was 89.6%. Wounds identified at baseline on the target limb had completely healed in 172/243 (70.8%) of the RC5-6 subjects by 1 year. Additionally, the overall quality of life, as measured by VascuQoL, improved from baseline to 1 year. CONCLUSION: LIBERTY investigated real-world PAD patients with independent oversight of outcomes. This analysis of LIBERTY RC5-6 patients demonstrates that peripheral endovascular device intervention can be successful in CLI patients, with low rates of major amputation and improvement in wound healing and quality of life through 1-year follow-up.LIBERTY 360, https://clinicaltrials.gov/ct2/show/NCT01855412, ClinicalTrials.gov Identifier: NCT01855412.

Orbital Atherectomy for the Treatment of Long (≥25-40 mm) Severely Calcified Coronary Lesions: ORBIT II Sub-Analysis.

BACKGROUND: Orbital atherectomy (OA) is an effective method of lesion preparation of severely calcified vessels prior to stent deployment. Long calcified lesions may lead to higher risk of post-procedural complications, yet the optimal treatment strategy has not been established. In this study we sought to determine the safety and efficacy of OA in patients with long (≥25-40 mm) calcified target lesions. METHODS: ORBIT II was a single-arm trial that enrolled 443 patients at 49 U.S. sites. De novo, severely calcified coronary lesions were treated with OA prior to stenting. Patients treated with the OA device were stratified into two groups according to target lesion length as visually estimated by the investigator: those with short (<25 mm; N = 314) vs. long (≥25-40 mm; N = 118) lesions. Lesions >40 mm were excluded per protocol. The primary endpoint was the 3-year major adverse cardiac event (MACE) rate, defined as a composite of cardiac death, myocardial infarction (MI), and target vessel revascularization (TVR). RESULTS: The 3-year MACE rates in patients with short (<25 mm) vs. long (≥25-40 mm) lesions were 21.1% vs. 29.9% respectively (p = 0.055). The rate of cardiac death (6.5% vs. 7.8%, p = 0.592) and TVR (8.5% vs. 13.7%, p = 0.153) did not significantly differ. The rate of MI (CK-MB > 3× ULN) at 3 years was significantly higher in patients with long (≥25-40 mm) lesions (9.0% vs. 17.0%, p = 0.024), with the majority occurring in-hospital (7.0% vs. 13.6%, p = 0.037). CONCLUSIONS: Patients with long (≥25-40 mm) calcified target lesions had similar outcomes in terms of MACE at 3 years despite higher rates of MI, which mostly occurred in-hospital. Using the more contemporary SCAI definition of MI, there was no significant difference in rates of MI between the short (<25 mm) and long (≥25-40 mm) groups. Further studies are warranted to determine how OA compares to focal force balloon angioplasty, rotational atherectomy and other novel treatment options for long severely calcified lesions. SUMMARY FOR ANNOTATED TABLE OF CONTENTS: Percutaneous coronary intervention of long calcified lesions is inherently more complex and higher risk and may require more intensive lesion preparation. This sub-analysis of ORBIT II revealed that orbital atherectomy treatment of longer (≥25-40 mm) lesions was associated with a higher rate of MACE at 30 days, but not at 3 years. This difference, however, was driven primarily by a higher in-hospital non-Q-wave MI rate; using the more contemporary SCAI definition of MI, there was no significant difference in rates of MI between the short (<25 mm) and long (≥25-40 mm) groups.

Orbital Atherectomy for Treatment of Complex Severely Calcified Coronary Artery Lesions: Insights from a Veterans Affairs Cohort.

BACKGROUND: Coronary artery calcification remains a significant challenge to successful percutaneous coronary intervention (PCI). Orbital atherectomy (OA) is an effective treatment for severely calcified coronary artery lesions during PCI, but few data are available in the Veterans Affairs (VA) system which has an increasingly complex subset of patients. METHODS: Data were obtained from retrospective analysis of patients with severe coronary artery calcification who underwent OA followed by stent implantation from February of 2015 to July of 2018 at a single VA Medical Center. Kaplan-Meier analysis was utilized to assess the primary endpoints of 30-day and 1-year freedom from major adverse cardiac events [MACE: Cardiac Death, myocardial infarction (MI), or target vessel revascularization (TVR)]. RESULTS: Among 151 patients, baseline comorbidities included diabetes (57%), prior PCI (51%), congestive heart failure (36.4%), and prior coronary artery bypass grafting (23.2%). The most common indication for intervention was stable angina (54.3%). Seventeen percent of cases required hemodynamic support. Angiographic complication rates were low. Overall freedom from MACE was 96% at 30 days and 87.7% at 1 year. CONCLUSION: This single-center VA cohort demonstrates that patients with severely calcified and anatomically complex coronary artery lesions treated with OA had a low rate of angiographic complications and a high rate of one-year freedom from MACE. Moreover, this study included demographics underrepresented in clinical trials, including those with acute myocardial infarction, left main coronary artery disease, and bifurcation lesions.

Direct Stenting in Patients Treated with Orbital Atherectomy: An ORBIT II Subanalysis.

BACKGROUND: Direct stenting offers many potential advantages in appropriately selected lesions. Coronary artery calcification increases the complexity and risk of adverse events associated with percutaneous coronary intervention. This study aimed to examine the feasibility of direct stenting after treatment with orbital atherectomy (OA). METHODS: ORBIT II was a single-arm trial enrolling 443 subjects with de novo severely calcified coronary lesions treated with OA; direct stenting was utilized in 59.0% of cases. Procedural outcomes and 3-year major adverse cardiac event (MACE) rates were compared in subjects treated with pre-stent balloon dilatation versus direct stenting after OA. RESULTS: Procedural success (84.2% vs. 93.3%; p = 0.004) was significantly higher in the direct stenting cohort. 3-year MACE occurred less frequently in the direct stenting cohort (29.9% vs. 19.1%; p = 0.006), driven by lower rates of myocardial infarction and target lesion revascularization. In a propensity matched analysis, procedural success and 3-year MACE rates were similar in the pre-stent balloon dilatation and direct stenting groups (85.0% vs. 91.8%; p = 0.122 and 28.2% vs. 19.6%; p = 0.078, respectively). CONCLUSIONS: Orbital atherectomy facilitates direct stenting and is associated with high procedural success and favorable 3-year outcomes in carefully selected patients. Randomized studies are needed to assess the optimal strategy after lesion preparation with OA.

Orbital atherectomy for calcified femoropopliteal lesions: a current review.

The orbital atherectomy system is a novel form of atherectomy that uses orbital sanding and pulsatile forces, an effective method of treatment for peripheral atherosclerotic lesions with varying levels of occlusion. Although the devices only has a general indication from the FDA to treat atherosclerotic lesions, they are effective in treating all kinds of lesions, and can therefore mitigate effects of all severities of peripheral artery disease. This approach to endovascular therapy involves the use of differential sanding to preferentially ablate fibrous, fibrofatty and calcified lesions, while deflecting healthy intima away from the crown. The eccentrically mounted crown design allows the device to employ rhythmic pulsating forces that penetrate the medial layer, and cause cracking in the lesions in order to facilitate easier balloon inflation and intravascular drug elution. The combination of vessel modification and lumen enlargement through sanding can effectively restore blood flow to the extremities, and can eliminate risk of critical limb ischemia, as well as subsequent amputation. Extensive lab testing and clinical trials have confirmed the high success rates and low major adverse events associated with this form of treatment. The device is economically viable as well, since its cost is offset by the lower frequency of adjunctive therapy sessions when compared to other devices. Considering the results outlined in this manuscript, the Diamondback 360° is an effective form of atherectomy therapy for peripheral artery disease. In-depth understanding of the operation preparation, procedure, and best imaging techniques can help to optimize outcomes.

Outcomes after Atherectomy Treatment of Severely Calcified Coronary Bifurcation Lesions: A Single Center Experience.

BACKGROUND: Coronary bifurcation and calcified lesions account for 15-20% and 6%-20% of percutaneous coronary interventions (PCI), respectively. Treatment of these lesions is associated with high periprocedural complication rates and unfavorable long-term clinical outcomes, including high rates of revascularization. This retrospective, single-center study evaluated the outcomes of atherectomy treatment for heavily calcified coronary bifurcation lesions. METHODS: Patients who underwent a coronary atherectomy procedure to treat a heavily calcified lesion between January 2010 and March 2016 at Metropolitan Heart and Vascular Institute (Minneapolis, MN) were included in this retrospective study. Data were stratified to compare atherectomy treatment of coronary bifurcation lesions vs non-bifurcation lesions. Additionally, data were compared based on type of atherectomy utilized during the index procedure, either orbital (OAS) or rotational (RA) atherectomy. Major adverse cardiac events (MACE), defined as a composite of death, myocardial infarction (MI), and target vessel revascularization (TVR), were assessed at 30 days post-procedure. RESULTS: Among the 177 patients treated with atherectomy, 72 patients had bifurcation lesions. Compared to patients with non-bifurcation lesions, patients with bifurcation lesions were more likely to have a history of prior PCI or coronary artery bypass grafting. Bifurcation lesions required a higher volume of contrast. There were similar low rates of slow flow/no-reflow (2.8% bifurcations vs 1.0% non-bifurcation; p = 0.355). The 30-day rates of death (1.4% vs 1.9%; p = 0.794), MI (0% vs 0%; p = NA), and TVR (0% vs 1.0%; p = 0.406) were similar in patients with bifurcation lesions versus those without, respectively. An atherectomy sub-analysis (OAS vs RA) of the patients with bifurcation lesions showed that OAS utilization was associated with shorter procedure time (81 min vs 109 min; p = 0.026) and fluoroscopy time (18 min vs 27 min; p = 0.007) compared to RA, respectively-no significant differences in baseline demographic or lesion characteristics were noted in the bifurcation atherectomy sub-groups, except for higher beta/calcium blocker use in RA bifurcation subjects. CONCLUSIONS: The results of this study demonstrated that atherectomy treatment in patients with heavily calcified coronary bifurcation lesions is feasible, resulting in similar low 30-day MACE rates as compared to patients with non-bifurcation lesions. In addition, in this study OAS utilization versus RA in bifurcation lesions was associated with significantly shorter procedure and fluoroscopy time. Further studies are needed to assess the safety and efficacy of atherectomy in patients with severely calcified bifurcation lesions. SUMMARY FOR ANNOTATED TABLE OF CONTENTS: This retrospective, single-center study evaluated the outcomes of orbital and rotational atherectomy treatment for heavily calcified coronary bifurcation lesions as compared to non-bifurcation lesions. The results demonstrate that atherectomy treatment in patients with heavily calcified coronary bifurcation lesions is feasible, resulting in similarly low 30-day MACE rates as compared to patients with non-bifurcation lesions. In addition, in this study OAS utilization versus RA in bifurcation lesions was associated with significantly shorter procedure and fluoroscopy time.

Procedural and Long-Term Ischemic Outcomes of Tight Subtotal Occlusions Treated with Orbital Atherectomy: An ORBIT II Subanalysis.

BACKGROUND/PURPOSE: Orbital atherectomy is an effective treatment strategy to modify severely calcified coronary lesions prior to stent placement. Traversing a severely calcified subtotal occlusion with the crown may be more challenging compared with a less severely stenotic lesion. The purpose of this ORBIT II subanalysis was to evaluate outcomes post-orbital atherectomy (OA) treatment of lesions with ≥95% stenosis. METHODS/MATERIALS: ORBIT II, a single-arm, prospective, multicenter trial, enrolled 443 subjects with severely calcified coronary lesions. Patients with chronic total occlusions were excluded from the trial. Subjects with the OA device activated were stratified based on pre-procedure percent stenosis: ≥95% stenosis (N = 91) and <95% stenosis (N = 341). Procedural success and 3-year major adverse cardiac event (MACE) rates were compared. RESULTS: The severe angiographic complications rates were 6.6% and 6.7% in the ≥95% and <95% stenosis groups, respectively. There was no significant difference in procedural success (94.5% vs. 88.3%, p = 0.120). 3-year MACE rates were similar (27.1% vs. 22.5%, p = 0.548), as were the rates of cardiac death (5.7% vs. 7.1%, p = 0.665) and MI (7.9% vs. 12.1%, p = 0.244). The TVR rate was higher in the ≥95% stenosis group (19.1% vs. 7.5%, p = 0.004). CONCLUSIONS: In ORBIT II, OA treatment of lesions with ≥95% stenosis resulted in a high rate of procedural success. Although the 3-year revascularization rate was higher in the ≥95% stenosis group, it is not unexpected given the challenge of treating such complex lesions. The results of this analysis suggest that OA may be a reasonable treatment strategy for tight, severely calcified subtotal occlusions. SUMMARY: The purpose of this ORBIT II subanalysis was to evaluate outcomes post-orbital atherectomy (OA) treatment of lesions with ≥95% stenosis. In ORBIT II, OA treatment of lesions with ≥95% stenosis resulted in a high rate of procedural success. Although the 3-year revascularization rate was higher in the ≥95% stenosis group, it is not unexpected given the challenge of treating such complex lesions. The results of this analysis suggest that OA may be a reasonable treatment strategy for tight, severely calcified subtotal occlusions.

Acute outcomes after coronary orbital atherectomy at a single center without on-site surgical backup: An experience in diabetics versus non-diabetics.

BACKGROUND: Percutaneous coronary intervention (PCI) of severely calcified lesions is associated with a high risk of angiographic complication, incomplete stent expansion, and restenosis. The prevalence of calcification is increased in diabetics (DM) and the PCI outcome in this population is often suboptimal. Treatment with orbital atherectomy (OA) in severely calcified lesions has been shown to result in favorable procedural outcomes and low reintervention rates; in DM and non-DM. We sought to determine the acute safety of OA in a center without on-site surgical backup in DM and non-DM. METHODS: All comers treated with OA at Sanford Bemidji Heart and Vascular Center (Bemidji, MN) from 8/30/16 to 4/14/17 were included in this retrospective analysis. Baseline, procedure, and acute outcome data were compared in DM and non-DM patients. RESULTS: Of the 70 patients treated with OA, 40% were DM. History of hypertension and chronic renal disease were more prevalent in the DM group. Successful stent delivery occurred in 96.4% of DM and 100% in non-DM, respectively. None of the patients treated with OA died or experienced abrupt closure, severe dissection, embolization, or no reflow. The overall perforation and slow flow rates were 1.4%. One non-DM patient had a non-target vessel MI due to side branch closure. CONCLUSIONS: Our study demonstrates the safety of OA in a center without on-site surgical backup. In this study, OA treatment resulted in a high rate of successful stent delivery and low rates of angiographic complications and acute MACE, in DM and non-DM patients. SUMMARY: In this retrospective study we sought to determine the acute safety of coronary orbital atherectomy treatment in a center without on-site surgical backup in diabetic and non-diabetic patients. None of the patients treated with orbital atherectomy died or experienced abrupt closure, severe dissection, embolization, or no reflow; the overall perforation and slow flow rates were 1.4% and one non-diabetic patient had a non-target vessel myocardial infarction due to side branch closure. Our study demonstrates the safety of orbital atherectomy in a center without on-site surgical backup; orbital atherectomy treatment resulted in a high rate of successful stent delivery and low rates of angiographic complications and acute major adverse cardiac events in diabetic and non-diabetic patients.

Impact of diabetes mellitus on procedural and one year clinical outcomes following treatment of severely calcified coronary lesions with the orbital atherectomy system: A subanalysis of the ORBIT II study.

OBJECTIVES: The goal of the study was to investigate the safety and efficacy of the coronary orbital atherectomy system to treat severe coronary artery calcification (CAC) prior to stent placement in diabetic and non-diabetic patients. BACKGROUND: The ORBIT II study reported the safety and efficacy of orbital atherectomy treatment in 443 patients with severe CAC. Percutaneous coronary intervention in diabetic patients is associated with an increased risk of major adverse cardiac events (MACE) compared with non-diabetics. The outcomes of diabetic patients who undergo orbital atherectomy are unknown. METHODS: Patients were sub-grouped as either diabetic (160/443, 36.1%) or non-diabetic (283/443, 63.9%). The MACE rate, defined as cardiac death, myocardial infarction (MI; CK-MB > 3X ULN), and target vessel revascularization, was examined at 30 days and 1 year after treatment. RESULTS: Procedural success was similar in the diabetic and non-diabetic groups (89.3 vs. 88.6%, P = 0.88). There was no significant difference in the 30-day and 1-year MACE rates between the diabetic and non-diabetic groups (30 day: 8.8 vs. 11.3%; P = 0.40; 1 year: 17.1 vs. 16.7%, P = 0.97). The individual components of cardiac death (3.9 vs. 2.9%, P = 0.58), MI (9.4 vs. 11.3%, P = 0.52), and target vessel revascularization (5.9 vs. 5.8%, P = 0.99) were also similar in both groups at 1 year. CONCLUSIONS: The rates of adverse clinical events in diabetic patients who underwent orbital atherectomy were low and similar to non-diabetic patients. This study suggests orbital atherectomy is a reasonable treatment strategy for diabetic patients with severe CAC.

Utilizing intravascular ultrasound imaging prior to treatment of severely calcified coronary lesions with orbital atherectomy: An ORBIT II sub-analysis.

OBJECTIVES: We sought to assess the clinical outcomes when intravascular ultrasound (IVUS) was used prior to orbital atherectomy treatment (OA) versus angiography alone for lesion assessment. BACKGROUND: Percutaneous coronary intervention (PCI) of severely calcified lesions is associated with high rates of major adverse cardiac events (MACE). IVUS provides additional diagnostic information to optimize PCI. METHODS: ORBIT II was a single-arm study of 443 patients with de novo, severely calcified coronary lesions treated with OA before stent placement. Patients with IVUS imaging prior to OA (N = 35) were compared to patients without IVUS imaging for initial lesion assessment (N = 405). In this post-hoc sub-analysis procedural outcomes and the 3-year MACE rate were evaluated. RESULTS: The rates of severe angiographic complications were low in patients with and without IVUS imaging prior to OA. There was a significant reduction in the number of stents used in patients with IVUS imaging prior to OA (1.0 ± 0.2 vs 1.3 ± 0.6; P = 0.006) and increased post-OA mean minimal lumen diameter (MLD) (1.6 ± 0.6 mm vs 1.2 ± 0.5 mm; P < 0.001). The 3-year MACE rate was similar in both groups (IVUS: 14.3% vs No IVUS: 24.2%; P = 0.26). CONCLUSIONS: There were significantly fewer stents placed, increased post-OA MLD, and similar 3-year MACE outcomes in patients with IVUS assessment of the degree of lesion calcification prior to OA as compared to patients with angiographic assessment of the degree of lesion calcification. Further studies are needed to determine the optimal integration of intravascular imaging with OA.

Atherectomy Devices for the Treatment of Calcified Coronary Lesions.

The presence of moderate and severe coronary artery calcification (CAC) is associated with higher rates of angiographic complications during percutaneous coronary intervention (PCI), as well as higher major adverse cardiac events compared with noncalcified lesions. Diabetes mellitus, a risk factor for CAC, is increasing in the United States. Vessel preparation before PCI with atherectomy can facilitate successful stent delivery and expansion that may otherwise not be possible. We review here CAC prevalence, risk factors, and impact on PCI, as well as the currently available coronary atherectomy devices including rotational atherectomy, orbital atherectomy, and laser atherectomy.

Sox7 is regulated by ETV2 during cardiovascular development.

Vasculogenesis/angiogenesis is one of the earliest processes that occurs during embryogenesis. ETV2 and SOX7 were previously shown to play a role in endothelial development; however, their mechanistic interaction has not been defined. In the present study, concomitant expression of Etv2 and Sox7 in endothelial progenitor cells was verified. ETV2 was shown to be a direct upstream regulator of Sox7 that binds to ETV2 binding elements in the Sox7 upstream regulatory region and activates transcription. We observed that SOX7 over-expression can mimic ETV2 and increase endothelial progenitor cells in embryonic bodies (EBs), while knockdown of Sox7 is able to block ETV2-induced increase in endothelial progenitor cell formation. Angiogenic sprouting was increased by ETV2 over-expression in EBs, and it was significantly decreased in the presence of Sox7 shRNA. Collectively, these studies support the conclusion that ETV2 directly regulates Sox7, and that ETV2 governs endothelial development by regulating transcriptional networks which include Sox7.

Nkx2-5 mediates differential cardiac differentiation through interaction with Hoxa10.

The regulation of cardiac differentiation is complex and incompletely understood. Recent studies have documented that Nkx2-5-positive cells are not limited to the cardiac lineage, but can give rise to endothelial and smooth muscle lineages. Other work has elucidated that, in addition to promoting cardiac development, Nkx2-5 plays a larger role in mesodermal patterning although the transcriptional networks that govern this developmental patterning are undefined. By profiling early Nkx2-5-positive progenitor cells, we discovered that the progenitor pools of the bisected cardiac crescent are differentiating asynchronously. This asymmetry requires Nkx2-5 as it is lost in the Nkx2-5 mutant. Surprisingly, the posterior Hox genes Hoxa9 and Hoxa10 were expressed on the right side of the cardiac crescent, independently of Nkx2-5. We describe a novel, transient, and asymmetric cardiac-specific expression pattern of the posterior Hox genes, Hoxa9 and Hoxa10, and utilize the embryonic stem cell/embryoid body (ES/EB) model system to illustrate that Hoxa10 impairs cardiac differentiation. We suggest a model whereby Hoxa10 cooperates with Nkx2-5 to regulate the timing of cardiac mesoderm differentiation.

Nkx2-5 Regulates Tdgf1 (Cripto) Early During Cardiac Development.

Congenital Heart Disease (CHD) is the most frequent and deadly birth defect. Patients with CHD that survive the neonatal period often progress to develop advanced heart failure requiring specialized treatment including cardiac transplantation. A full understanding of the transcriptional networks that direct cardiac progenitors during heart development will enhance our understanding of both normal cardiac function and pathological states. These findings will also have important applications for emerging therapies and the treatment of congenital heart disease. Furthermore, a number of shared transcriptional pathways or networks have been proposed to regulate the development and regeneration of tissues such as the heart. We have utilized transgenic technology to isolate and characterize cardiac progenitor cells from the developing mouse heart and have begun to define specific transcriptional networks of cardiovascular development. Initial studies identified Tdgf1 as a potential target of Nkx2-5. To mechanistically dissect the regulation of this molecular program, we utilized an array of molecular biological techniques to confirm that Nkx2-5 is an upstream regulator of the Tdgf1 gene in early cardiac development. These studies further define Nkx2-5 mediated transcriptional networks and enhance our understanding of cardiac morphogenesis.