Thirty-day TAVR Results from the Evolut Low Risk Bicuspid Study

Educational Objectives

After completing the activity, the clinician will be better able to discuss the safety and efficacy of transcatheter aortic valve replacement in patients with bicuspid aortic valve stenosis who are at low surgical risk.

Summary

Interviewer: Deepak L. Bhatt, MD, MPH, FACC

Take-home Messages:

• Much has been learned from studies evaluating transcatheter aortic valve replacement (TAVR), but patients with bicuspid disease were excluded from nearly all these trials.
• Now there are early results from the Evolut Low Risk Bicuspid Study, suggesting that TAVR with the self-expanding Evolut platform is safe and effective.
• The choice between TAVR and surgical replacement should be based on a multidisciplinary heart team discussion that includes anatomic, clinical, and patient social factors.

Numerous large-scale and randomized clinical trials have demonstrated the safety and effectiveness of TAVR as compared with surgical aortic valve replacement (SAVR). TAVR has now been approved as a therapy for patients with severe symptomatic aortic stenosis regardless of their surgical risk profile.

In the Evolut Low Risk Trial, TAVR with a self-expanding supra-annular bioprosthesis was noninferior to surgery with respect to the composite endpoint of death or disabling stroke at 24 months.¹

However, one limitation of the available data has been that patients with bicuspid aortic stenosis were generally excluded from TAVR trials. Investigators were concerned about asymmetric calcification, elliptical shape, potential incomplete valve expansion, procedural technical issues, and other matters.

It is also important to acknowledge that bicuspid aortic valve disease differs from tricuspid disease not only in the number of leaflets present but also in several other anatomic and pathophysiologic areas, including:

• an increased incidence of aortopathy with dilation of the aortic root and ascending aorta,
• frequent atypical location of coronary artery ostia,
• asymmetric leaflet calcification,
• larger-sized annuli, and
• higher calcium scores with bulky leaflet calcification and fused raphe.

Probably as a result of these anatomic differences, the results of early-generation TAVR systems in patients with bicuspid aortic valve disease were notable for worse in-hospital outcomes, decreased device success, and an increased incidence of paravalvular leak, device malpositioning, and aortic injury.

Since then, system modifications have addressed many of these issues, producing subsequent generations of devices with various improvements, such as improved sealing at the level of the annulus and the ability to recapture and reposition the valve to assist with obtaining the optimal implant depth before final release.

Now there is a need to prospectively analyze results from these newer devices in patients with bicuspid aortic stenosis who are at low surgical risk.

Preliminary Data

There was a preliminary analysis from the Society of Thoracic Surgeons/American College of Cardiology (STS/ACC) Transcatheter Valve Therapy (TVT) Registry of patients with bicuspid aortic valve disease who underwent TAVR with the balloon-expandable SAPIEN 3 transcatheter aortic valve.² These patients showed no significant differences in 30-day or 1-year mortality compared with a propensity-matched group of patients with tricuspid valve stenosis.

Now there are prospective data from the Evolut Low Risk Bicuspid Study, which was conducted at high-volume, experienced centers. While the study had a nonrandomized design, investigators used a standardized implantation technique, consistent annular sizing, and pre-TAVR balloon dilation, and they maintained rigorous adherence to patient selection parameters.

Data from 150 patients showed that TAVR using the Evolut supra-annular self-expanding valve achieved excellent early results. Device success occurred in 95.3% of these low-risk bicuspid patients. Mortality and stroke were very low at 30 days (Table 1); there were low rates of aortic regurgitation (no moderate/severe regurgitation) and consistent hemodynamics across Sievers classification types. Patients will continue to be followed for up to 10 years.

In presenting the data at ACC.20 virtual, Basel Ramlawi, MD (Valley Health System, Winchester, Virginia), noted that the choice between TAVR and SAVR should be based on a multidisciplinary heart team discussion that includes the condition of the valve itself, anatomic and clinical variables, as well as patient age and social factors.

Higher Surgical Risk

Dr. Ramlawi and colleagues have now analyzed Evolut data from the STS/ACC TVT Registry comparing TAVR in bicuspid and tricuspid aortic valves in patients at increased surgical risk.³ They analyzed data from 932 patients with bicuspid aortic valve stenosis who underwent elective TAVR with the self-expanding, repositionable, Evolut R or Evolut PRO valve. These results were then compared with a group of 26,154 patients with tricuspid aortic stenosis who underwent TAVR during the same period (July 2015 to September 2018).

At baseline, patients with bicuspid valves were younger, had fewer cardiac comorbidities, and had lower Society of Thoracic Surgeons Predicted Risk of Mortality scores (5.3 ± 4.2% vs. 6.9 ± 4.8%; p < 0.001). To account for these differences, propensity matching was performed, which resulted in 929 matched pairs. Within these matched groups, results were comparable for all-cause mortality at 30 days and 1 year, as were the rates of stroke (Table 2).

The number of patients in the bicuspid group who required aortic valve reintervention was slightly larger than in the tricuspid group at 30 days and at 1 year (Table 2). But, overall, in patients at increased surgical risk, TAVR for bicuspid aortic valve stenosis indicates acceptable safety outcomes with low complication rates.

References:

1. Popma JJ, Deeb GM, Yakubov SJ, et al. Transcatheter aortic-valve replacement with a self-expanding valve in low-risk patients. N Engl J Med 2019;380:1706-15.
2. Makkar RR, Yoon SH, Leon MB, et al. Association Between Transcatheter Aortic Valve Replacement for Bicuspid vs Tricuspid Aortic Stenosis and Mortality or Stroke. JAMA 2019;321:2193-202.
3. JK, Kaple RK, Ramlawi B, et al. Transcatheter Aortic Valve Replacement in Bicuspid Versus Tricuspid Aortic Valves from the STS/ACC TVT Registry. JACC Cardiovasc Interv 2020 May 27 [published online ahead of print]. doi: 10.1016/j.jcin.2020.03.022 https://interventions.onlinejacc.org/content/early/2020/05/23/j.jcin.2020.03.022

   

Table 1. Evolut Low Risk Bicuspid Study

          Outcomes at 30 Days (N = 150)

All-cause mortality or disabling stroke	2 (1.3%
All-cause mortality	1 (0.7%)
Disabling stroke	1 (0.7%)
Nondisabling stroke	5 (3.3%)
Major vascular complication	2 (1.3%)
Aortic dissection	0 (0%)
Annular rupture	0 (0%)
New permanent pacemaker	22 (15.1%)
Coronary artery obstruction	1 (0.7%)

 

 

Table 2. TAVR in Bicuspid vs. Tricuspid Aortic Valves in Patients at Increased Surgical Risk: Select Clinical Outcomes at 30 Days and 1 Year (Adjusted Cohort)

	30 Days			1 Year
	Bicuspid	Tricuspid	p Value	Bicuspid	Tricuspid	p Value
All-cause mortality	2.6%	1.7%	0.18	10.4%	12.4%	0.63
Stroke	3.4%	2.7%	0.41	3.9%	4.4%	0.93
Pacemaker implantation	15.4%	13.7%	0.30	16.4%	15.9%	0.52
AV reintervention	0.8%	0.1%	0.03	1.7%	0.3%	0.01

AV = aortic valve.

Readings

Disclosures

Basel Ramlawi, MD, FACC, FACS, Winchester, VA

LivaNova PLC (A,C); Medtronic (A,C); AtriCure Inc (A,C)

Interviewer: Deepak L. Bhatt, MD, MPH, FACC

Abbott (G); Afimmune Limited (G); Amarin Corporation (G); Amgen Inc (G); AstraZeneca (G); Bristol-Myers Squibb Corporation (G); Chiesi USA Corp (G); Eisai Co Ltd (G); Eli Lilly and Co (G); Ethicon (G); FlowCo (G); Forest Laboratories (G); Fractyl Laboratories (G); Idorsia Pharmaceuticals Ltd (G); Ironwood Medical Information Technologies (G); Ischemix, Lexicon Pharmaceuticals Inc (G); Medtronic (G); Novo Nordisk A/S (G); Pfizer Inc (G); PhaseBio Pharmaceuticals Inc (G); PLx Pharma Inc (G); Regeneron (G); Roche (G); Sanofi Aventis (G); Synaptic Medical Inc (G);Takeda Pharmaceutical Co Ltd (G); The Medicines Company (G); Cereno Scientific AB (A); PhaseBio Pharmaceuticals Inc (A)

Acknowledgements

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0 CE contact hours.

Lecture ID:

AC520904

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.

More Details - Certification & Accreditation