Coronary Orbital Atherectomy in Patients With Severe Aortic Stenosis

Abstract

Objectives. Orbital atherectomy (OA) has been shown to be safe and effective in patients with severe calcific coronary artery disease; however, there is a paucity of data on OA use in patients with concomitant severe aortic stenosis (AS). Methods. A retrospective analysis of consecutive patients undergoing coronary OA treatment of severely calcified lesions, from January 2014 to September 2020 at the Mount Sinai Medical Center, Miami Beach, Florida (MSMCMB), was completed. Data were analyzed to assess rates of angiographic complications, successful stent placement, and in-hospital major adverse cardiovascular event (MACE; defined as the composite of cardiac death, myocardial infarction, ischemic cerebrovascular accident [CVA], and hemorrhagic CVA) in AS vs non-AS patients. Results. A total of 609 patients underwent OA; of those, 32 (5.3%) had severe AS. The AS patient cohort was significantly older (80.3 years vs 73.7 years; P<.001), with a significantly higher percentage of Hispanic or Latino individuals (75% vs 56.5%; P=.04) and lower estimated glomerular filtration rate (64.6 mL/min/1.73 m² vs 76.6 mL/min/1.73 m²; P =.03) than the non-AS cohort. Angiographic complication rates were similar and both groups resulted in 100% successful stent placement. There was no difference in MACE rates between the AS and non-AS cohorts (3.1% vs 1.4%; P=.39). Conclusions. This study represents the largest real-world comparison of OA use in AS vs non-AS patients. OA appears feasible, safe, and effective prior to stent placement in patients with severe AS. Prospective randomized trials are needed to determine the ideal revascularization strategy for AS patients.

Keywords: calcified plaque modification, coronary artery calcium, orbital atherectomy, percutaneous coronary intervention, severe aortic stenosis

Aortic stenosis (AS) is the most prevalent valvular disease in older adults, reaching 10% in octogenarians.¹ Risk factors for AS, such as dyslipidemia, hypertension, diabetes mellitus, and chronic kidney disease, are similar to those for calcified atherosclerotic cardiovascular disease.^2,3 Furthermore, the prevalence of significant coronary artery disease (CAD) in patients with severe AS is approximately 75%.⁴ Transcatheter aortic valve replacement (TAVR) in severe AS patients with concomitant significant CAD is challenging; however, it has been shown that percutaneous coronary intervention (PCI) can be performed in patients with AS and CAD without an increased risk of short-term mortality compared with patients without AS.⁵ In fact, current guidelines recommend PCI in patients with severe AS and significant CAD (luminal reduction >70% diameter, fractional flow reserve <0.8, instantaneous wave-free ratio <0.89) for the management of valvular heart disease.⁶

Atherectomy is an effective treatment for significant CAD, especially for severely calcified coronary lesions prior to PCI.⁷ Orbital atherectomy (OA) has been shown to be safe and effective in calcified plaque modification prior to PCI in complex and/or high-risk patients.^8-10 In addition, OA allows continuous blood flow during treatment, which may improve the ability for patients with severe AS to tolerate atherectomy.¹¹ However, there is a paucity of safety and efficacy data regarding OA treatment of patients with severe AS.¹² The main goal of this retrospective comparative study is to evaluate the clinical outcomes of OA in patients with and without severe AS.

Methods

Study design and endpoints. All patients who underwent ­coronary OA at Mount Sinai Medical Center in Miami Beach, Florida (MSMC) from January 2014 through June 2020 were included in this retrospective analysis. The study was approved by the MSMC institutional review board. Patients with severe AS, based on either clinical history or echocardiogram within 6 months of PCI, comprised the AS group, while all others were included in the non-AS group. All procedures were performed using the Diamondback 360 Coronary Orbital Atherectomy System (Cardiovascular Systems, Inc)⁷ prior to stent placement. Data were retrospectively abstracted from MSMC’s CathPCI National Cardiovascular Data Registry (NCDR) database and analyzed to assess the rates of angiographic complications, successful stent placement, and in-hospital major adverse cardiovascular event (MACE; defined as the composite of cardiac death, myocardial infarction [MI], ischemic cerebrovascular accident [CVA], and hemorrhagic CVA) in AS vs non-AS patients.

Statistical analysis. Baseline and procedural characteristics are presented as n (%) for binary variables or mean ± standard deviation for continuous variables. Freedom from MACE, bleeding, cardiogenic shock, and heart failure values were determined via Kaplan-Meier and Peto’s method—values are shown as % (95% confidence interval [CI]). Missing data for baseline characteristics were imputed via single imputation using the Markov Chain Monte Carlo method with a single chain. The starting value for the chain was computed from the expectation-maximization algorithm. The resulting P-value of the comparison of AS vs non-AS was calculated via Fisher’s Exact test for frequency variables or Student’s t test for continuous variables. A P-value <.05 was considered statistically significant. Analyses were conducted in SAS, version 9.4.

Results

Demographics. A total of 609 patients underwent plaque modification with OA prior to stenting over a 6-year period, and of those, 32 patients (5.3%) had severe AS. The AS patient cohort was significantly older (80.3 years vs 73.7 years; P<.001), with a significantly higher percentage of Hispanic or Latino individuals (75% vs 56.5%; P=.04) than the non-AS cohort. Furthermore, the estimated glomerular filtration rate (eGFR) was significantly lower in the AS cohort (64.6 mL/min/1.73 m² vs 76.6 mL/min/1.73 m²; P=.03). Interestingly, the non-AS cohort had a numerically greater history of prior coronary artery bypass graft surgery (CABG) than the AS cohort (14.4% vs 6.3%; P=.29). Otherwise, there were no differences in the remaining baseline characteristics between the 2 cohorts (Table 1).

Procedural results. The lesion and vessel characteristics were similar between the cohorts (Table 2). The most common vessels treated were the left anterior descending coronary artery, the right coronary artery (RCA), and the left circumflex (LCX) artery (Table 2). Numerically, however, there were more LCX lesions in the non-AS cohort (11.7% vs 22.6%; P=.05) and more RCA lesions in the AS cohort (33.3% vs 23.5%; P=.09). Overall, on average the lesions were highly stenotic (85%), long (22.4 mm), and complex, with over 50% of the lesions classified as type C via the American College of Cardiology/American Heart Association lesion classification system (Table 2). All patients were treated with OA to optimize stent placement and expansion during PCI, resulting in successful stent placement in all patients (Table 3). No severe angiographic complications occurred in the AS cohort and there was a high rate of freedom from bleeding, cardiogenic shock, and heart failure in both cohorts (Table 3). Lastly, preprocedural persistent slow flow/no reflow (10%/1.7% vs 9.5%/0.8%) decreased to 0% post procedure in both the AS and non-AS cohorts.

In-hospital MACE. The in-hospital rate of freedom from MACE, a composite of cardiac death, MI, and stroke (ischemic or hemorrhagic CVAs), was high overall, with no significant difference between AS and non-AS patients (96.9% vs 98.6%; P=.39) (Table 4).

Discussion

This retrospective study of 609 patients, which compared coronary OA use in AS vs non-AS PCI patients, confirms a previous small cohort report¹² that plaque modification with OA before stenting can be performed successfully in AS patients. Furthermore, there was no increase in angiographic complication or in-hospital MACE rates as compared with non-AS patients.

CAD, often with heavy calcification, is highly prevalent in patients with severe AS referred for TAVR.⁴ The management of calcific CAD in these patients is still a matter of debate.¹³ Historically, coronary atherectomy prior to stent placement has not been performed routinely in severe AS patients as the outcomes of atherectomy/PCI in these patients have remained understudied.⁴ Some believe that most AS patients will not benefit from pre-TAVR PCI and that these procedures could be dangerous, especially in older and ill TAVR patients with severe AS.¹⁴ Others think that even though the treatment of calcified lesions prior TAVR could be challenging, PCI can be a way to improve procedural safety and outcomes of TAVR.⁵ Since there is a paucity of OA use in AS patients, we sought to retrospectively assess the utilization of OA in heavily calcified coronary lesions of AS patients compared with non-AS patients.

Baseline demographic comparison of AS vs non-AS patients. Similar to the findings in this analysis, AS patients with concomitant calcified coronary lesions have been shown previously to be older with multiple comorbidities, such as dyslipidemia, hypertension, and diabetes mellitus.^2,3 Besides age, eGFR was the only other significant difference in baseline characteristics observed in this retrospective analysis.

Interestingly, patients were 1.3 times more likely to identify themselves as Hispanic or Latino (HL) in the AS cohort as compared with the non-AS cohort (75% vs 56.5%; P=.04). This trend is a novel finding and important to note. Previous studies indicate that under-represented racial and ethnic groups experience a paradoxically lower prevalence or incidence of AS relative to white subjects, despite having a higher prevalence of traditional risk factors.¹⁵ Most studies of severe AS have focused largely on data from Black and White racial groups; thus, data from Hispanic populations with severe AS are limited. Given the changing demographics of the United States population, understanding the public health impact of AS across racial and ethnic groups is necessary.¹⁵ In a more recent analysis of the Transcatheter Valve Therapy registry from 2011 to 2016 by Alkhouli et al,¹³ relative to White patients, Black, Hispanic, and other non-White groups remained under-represented among patients undergoing TAVR in the United States. The reasons for this difference in TAVR receipt are likely multifactorial, but the lack of access to care and qualified services likely play a role in differences in receipt of TAVR procedures.¹⁶ Thus, when the HL population has appropriate access to care, as seen at this single center, there may actually be a higher prevalence of AS in this patient population compared with other ethnicities.

AS vs non-AS cohort outcomes. There were no severe dissections, perforations, or postprocedure slow flow/no reflow in the AS cohort and the rates of dissection and perforation were less than 1% in the non-AS cohort. It is important to emphasize that the preprocedural persistent slow flow/no reflow decreased to 0% post procedure, from 10% and 9.5% in the AS and non-AS cohorts, respectively. These outcomes were similar to those reported by Kassas et al¹⁷ (n = 24) and Beohar et al¹² (n = 18) in patients with severe AS and severely calcified CAD. In the current comparative retrospective analysis, none of the patients in the AS cohort had in-hospital MI, ischemic CVA or hemorrhagic CVA, heart failure, or any type of bleeding. Only 1 AS patient had in-hospital cardiac death and another patient suffered from cardiogenic shock. Less than 2% of the patients in the non-AS cohort had in-hospital MACE, cardiogenic shock, heart failure, or any type of bleeding. The rate of in-hospital death was much lower than the rate reported by Kassas et al;¹⁷ however, they stated that none of the in-hospital mortalities were related to the PCI.

To the best of our knowledge, these small single-arm cohort studies are the only published articles^12,17 where patients with severe AS and concomitant calcific CAD were treated with OA prior to TAVR. These previous single-center retrospective studies showed that OA-facilitated PCI can be safely performed in patients with severe AS and heavily calcified coronary lesions, resulting in low risk of complications and acceptable in-hospital, 30-day, and 1-year outcomes. The results of the current comparative study are novel in that they show that treating severely calcified coronary lesions of AS patients with OA is as safe and effective as the treatment of non-AS patients.

Study limitations. Our study has several limitations. First, the retrospective cohort study design may have increased the risk for selection bias. Second, the patient number between cohorts is imbalanced (32 AS patients vs 577 non-AS patients); however, the small number of AS patients is likely due to their high complexity and the single-center nature of the study. Third, a propensity-score matched analysis between the 2 groups was not completed. However, propensity matching did not seem warranted since there were no major differences in the baseline and/or procedural characteristics between the 2 groups. Finally, as this work was a single-center, observational, retrospective study, the results should be interpreted within the context of observational research and its limitations.

Conclusion

Patients with AS are at greater risk for complications during PCI than those without AS. In this large, real-world OA study, the in-hospital freedom from MACE rates in AS patients who underwent OA were high and similar to the non-AS patients. This study suggests that OA is a reasonable treatment strategy for AS patients with severe coronary artery calcification. Prospective randomized trials are needed to determine the ideal revascularization strategy for AS patients.

Affiliations and Disclosures

From ¹Columbia University Division of Cardiology at the Mount Sinai Medical Center, Miami Beach, Florida; ²Yale University Medical Center, New Haven, Connecticut; ³Clinical Scientific Affairs, Cardiovascular Systems, Inc, St Paul, Minnesota; and ⁴Columbia University Irving Medical Center, New York, New York.

Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. Dr Martinsen and Dr Igyarto are employed by and own stock in Cardiovascular Systems, Inc. The remaining authors report no conflicts of interest regarding the content herein.

Manuscript accepted March 17, 2022.

Address for correspondence: Nirat Beohar, MD, Mount Sinai Medical Center, 4300 Alton Rd, Miami Beach, FL 33140. Email: nirat.beohar@msmc.com

References

1. Fattouch K, Castrovinci S, Carità P. Aortic valve stenosis: treatments options in elderly high-risk patients. J Geriatr Cardiol JGC. 2016;13(6):473-474. doi:10.11909/j.issn.1671-5411.2016.06.008

2. Carabello BA, Paulus WJ. Aortic stenosis. Lancet Lond Engl. 2009;373(9667):956-966. doi:10.1016/S0140-6736(09)60211-7

3. Otto CM. Calcific aortic stenosis—time to look more closely at the valve. N Engl J Med. 2008;359(13):1395-1398. doi:10.1056/NEJMe0807001

4. Goel SS, Ige M, Tuzcu EM, et al. Severe aortic stenosis and coronary artery disease—implications for management in the transcatheter aortic valve replacement era: a comprehensive review. J Am Coll Cardiol. 2013;62(1):1-10. doi:10.1016/j.jacc.2013.01.096

5. Goel SS, Agarwal S, Tuzcu EM, et al. Percutaneous coronary intervention in patients with severe aortic stenosis: implications for transcatheter aortic valve replacement. Circulation. 2012;125(8):1005-1013. doi:10.1161/CIRCULATIONAHA.111.039180

6. Otto CM, Nishimura RA, Bonow RO, et al. 2020 ACC/AHA Guideline for the management of patients with valvular heart disease: executive summary: a report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2021;143(5):e35-e71. doi:10.1161/CIR.0000000000000932

7. Shlofmitz E, Martinsen BJ, Lee M, et al. Orbital atherectomy for the treatment of severely calcified coronary lesions: evidence, technique, and best practices. Expert Rev Med Devices. 2017;14(11):867-879. doi:10.1080/17434440.2017.1384695

8. Chambers JW, Feldman RL, Himmelstein SI, et al. Pivotal trial to evaluate the safety and efficacy of the orbital atherectomy system in treating de novo, severely calcified coronary lesions (ORBIT II). JACC Cardiovasc Interv. 2014;7(5):510-518. doi:10.1016/j.jcin.2014.01.158

9. Lee MS, Shlofmitz E, Kaplan B, Alexandru D, Meraj P, Shlofmitz R. Real-world multicenter registry of patients with severe coronary artery calcification undergoing orbital atherectomy. J Interv Cardiol. 2016;29(4):357-362. doi:10.1111/joic.12310

10. Desai R, Mirza O, Martinsen BJ, Kumar G. Plaque modification of severely calcified coronary lesions via orbital atherectomy: single-center observations from a complex Veterans Affairs cohort. Health Sci Rep. 2018;1(12):e99. doi:10.1002/hsr2.99

11. Shlofmitz E, Goldberg AH, Pollack S, et al. 100.41 Safety and feasibility of orbital atherectomy in patients with aortic stenosis. JACC Cardiovasc Interv. 2019;12(Suppl 4):S12-S13. doi:10.1016/j.jcin.2019.01.046

12. Beohar N, Mohammed N, Kherada N, Igyarto Z, Martinsen BJ. Percutaneous coronary intervention of complex calcific coronary lesions utilizing orbital atherectomy prior to transcatheter aortic valve replacement. Cardiovasc Revasc Med. 2022;37:82-85. Epub 2021 Jun 22. doi:10.1016/j.carrev.2021.06.117

13. Alkhalil M, Jabri A, Puri R, Kalra A. Revascularization in the transcatheter aortic valve replacement population. Interv Cardiol Clin. 2021;10(4):553-563. doi:10.1016/j.iccl.2021.06.003

14. van den Boogert TPW, Vendrik J, Gunster JLB, et al. The impact of percutaneous coronary intervention on mortality in patients with coronary lesions who underwent transcatheter aortic valve replacement. J Invasive Cardiol. 2021;33(10):E823-E832.

15. Wilson JB, Jackson LR, Ugowe FE, et al. Racial and ethnic differences in treatment and outcomes of severe aortic stenosis: a review. JACC Cardiovasc Interv. 2020;13(2):149-156. doi:10.1016/j.jcin.2019.08.056

16. Bob-Manuel T, Sharma A, Nanda A, Ardeshna D, Skelton WP, Khouzam RN. A review of racial disparities in transcatheter aortic valve replacement (TAVR): accessibility, referrals and implantation. Ann Transl Med. 2018;6(1):10. doi:10.21037/atm.2017.10.17

17. Kassas I, Nagy A, Alonso A, et al. Orbital atherectomy for calcific coronary artery disease in patients with severe aortic stenosis: a safety and feasibility study. J Invasive Cardiol. 2019;31(7):E205-E210.

Related Reading

• Real-World Multicenter Coronary Lithotripsy Registry: Long-Term Clinical Follow-Up 
• Auryon Laser in Peripheral Arterial Interventions: A Single-Center Experience (Auryon-SCE)
• Intravascular Ultrasound Insights Into Perforation After Coronary Atherectomy
• Outcomes of Radial Versus Femoral Access in Patients With Severe Aortic Stenosis Undergoing Percutaneous Coronary Intervention Prior to Transcatheter Aortic Valve Replacement
• Transcatheter Aortic Valve Replacement in Nonagenarians: A Systematic Review and Meta-Analysis
• Efficacy and Safety of Postdilation for a Self-Expanding Transcatheter Heart Valve