Repeated Aortic Balloon Valvuloplasty in Elderly Patients With Aortic Stenosis Who Are Not Candidates for Definitive Treatment

Severe aortic stenosis (AS) in the elderly population is a condition associated with high morbidity and mortality, particularly after patients become symptomatic from their valvular disease. Worldwide, prevalence of severe AS in the elderly is noted to be 4.6%, equating to over 2.7 million patients over the age of 75 years in North America alone.^1,2 Surgical valve replacement remains the mainstay of treatment for severe AS patients, with clear superiority over medical therapy. However, as individuals continue to age, comorbidities increase, and risk profiles can dramatically shift, making surgical risk prohibitively high for some patients. With the introduction of transcatheter aortic valve replacement (TAVR), a larger number of patients originally thought to be inoperable can now be treated, with dramatic improvement in both quality of life and mortality when compared with medical management alone.³ That being said, there remains a group of patients who are even too high risk for TAVR, the so-called “Cohort C.” This patient subset consists of those individuals who have such significant cardiovascular or other comorbid conditions that the risks associated with TAVR would be too high for this patient population.⁴ It is in this subset of patients that balloon aortic valvuloplasty (BAV) becomes a viable treatment option, as described in this new study by Bordoni and colleagues.⁵ 

BAV was originally described by Dr Cribier in 1986, and consists of balloon dilation of the severely stenotic valve and fracturing the calcific raphes of the leaflets, resulting in increased aortic valve area.⁶ The acute area gain, however, is only temporary as there is prompt aortic recoil, which minimizes any acute dilatory benefit. Even with noted immediate improvement in patient symptomatology, initial enthusiasm for this procedure was quickly hampered as a result of only modest improvement in aortic hemodynamic parameters and limited durability, in the setting of significant periprocedural complications.⁷ Despite a resurgence of BAV in the TAVR era, the most recent iteration of the American Heart Association/American College of Cardiology valvular guidelines restricts BAV performance to a class-IIb, level of evidence C recommendation, to be considered only as a bridge for surgical valve replacement or TAVR in symptomatic severe AS patients.⁸ In spite of this, several centers have broadened the potential application of stand-alone BAV to include use in acutely unstable patients, including pregnant women with class-III/IV heart failure symptoms, those who need non-elective, high-risk, non-cardiac surgery, those with end-organ dysfunction secondary to severe AS, and most importantly, for symptomatic palliation in those without other treatment options.⁹ In recent years, BAV has increased in frequency given the increasing number of patients eligible for non-surgical aortic therapy.¹⁰  

Despite its increased use, BAV is not without risk. Initial experiences noted substantial patient morbidity and mortality, with significant complication rates as high as 25%.¹¹ These complications at the time of the procedure were related to stroke (3%), myocardial infarction (2%), moderate to severe aortic insufficiency (1%), arrhythmia or heart block with need for permanent pacemaker placement (4%-10%), prolonged hypotension (8%), cardiac tamponade (1%), and death (3%). Vascular complications related to device introduction and large sheath size including bleeding, limb ischemia, perforation, pseudoaneurysm, and fistula formation were also not uncommon, with surgery required in up to 7% of patients. Current balloon technology (Table 1) and improved procedural technique continue to decrease the risk posed to patients, with current major complication rates noted between 1%-2%.^5,12

In the current article, Bordoni and colleagues have sought to evaluate the potential efficacy and safety of repeated BAV procedures in a high-risk elderly population who were not candidates for more definitive therapy. In this retrospective analysis, the authors noted reduction in mean transaortic gradient of >50% in 26.7% of cases, with in-hospital death noted in 3.5% of patients, myocardial infarction occurring in 4%, stroke occurring in 0.9%, and major bleeding, major vascular complications requiring surgical intervention, and significant aortic insufficiency occurring in 2.7% of procedures. With repeat BAV, no increase in complications was noted; however, efficacy of the procedure measured by both resultant aortic valve area and mean transaortic gradient reduction was noted to decrease with subsequent BAVs. Interestingly, while significant peripheral vascular complications remained low, and comparable to those seen in other interventional procedures requiring large-bore arterial access, those patients who experienced significant vascular complications during their first BAV procedure seemed to be at higher risk for similar significant complications on subsequent BAVs. Importantly, however, overall survival was noted to be 84.2%, 58.7%, and 42.8% at 1, 2, and 3 years, respectively, which is notably higher than other similar contemporary studies.³ 

As noted previously, despite initial symptomatic improvement, BAV results in only short-term relief of the obstruction caused by the severely calcified and stenotic aortic valve. If a resultant post-valvuloplasty aortic valve area of >1.0 cm² can be achieved, a patient’s symptomatic outcome can be more durable, but is still in no way permanent.¹² For patients in whom BAV is the only structural treatment available to relieve their symptomatology, repeat BAV performance is one of the only means to maintain symptomatic control in an otherwise very high-risk patient population. This paper by Bordoni and colleagues is a notable step forward, demonstrating the efficacy and safety in performing repeat BAV in a high-risk patient population with no other treatment options.

References

1.    Nkomo VT, Gardin JM, Skelton TN, et al. Burden of valvular heart disease: a population-based study. Lancet. 2006;368:1005-1011.

2.    Osnabrugge RL, Mylotte D, Head SJ, et al. Aortic stenosis in the elderly: disease prevalence and number of candidates for transcatheter aortic valve replacement: a meta-analysis and modeling study. J Am Coll Cardiol. 2013;62:1002-1012.

3.    Leon MB, Smith CR, Mack M, et al. Transcatheter aortic valve implantation for aortic stenosis in patients who cannot undergo surgery. N Engl J Med. 2010;363:1597-1607.

4.    Araque JC, Greason KL, Suri RM, et al. The role of balloon aortic valvuloplasty in patient with aortic valve stenosis and society of thoracic surgeons risk of 15% or higher. Ann Thorac Surg. 2015 Sep 23 (Epub ahead of print).

5.    Bordoni B, Moretti C, Morrozzini C, et al. Repeated aortic balloon valvuloplasty in elderly patients with aortic stenosis who are not candidates for definitive treatment. J Invasive Cardiol. 2015;27:E277-E284 (Epub 2015 Sept 15).

6.    Cribier A, Savin T, Saoudi N, Rocha P, Berland J, Lectac B. Percutaneous transluminal valvuloplasty of acquired aortic stenosis in elderly patients: an alternative to valve replacement? Lancet. 1986;1:63-67.

7.    Safian RD, Berman AD, Diver DJ, et al. Balloon aortic valvuloplasty in 170 consecutive patients. N Engl J Med. 1988;319:125-130.

8.    Nishimura RA, Otto CM, Bonow RO, et al. 2014 AHA/ACC guideline for the management of patients with valvular heart disease: a report of the America College of Cardiology/American Heart Association task force on practice guidelines. J Am Coll Cardiol. 2014;63:e57-e185.

9.    Pederson W, Sorajja P. Balloon aortic valvuloplasty: current indications and use in unique clinical settings. Cardiac Interventions Today. 2015;9:56-60; 73.

10.    Saia F, Marrozzini C, Ciuca C, et al. Emerging indications, in-hospital and long-term outcome of balloon aortic valvuloplasty in the transcatheter aortic valve implantation era. EuroIntervention. 2013;8:1388-1397.

11.    NHLBI Balloon Valvuloplasty Registry Participants. Percutaneous balloon aortic valvuloplasty: acute and 30-day follow-up results in 674 patients from the NHLBI balloon valvuloplasty registry. Circulation. 1991;84:2383-2397.

12.    Ben-Dor I, Pichard AD, Satler LF, et al. Complications and outcome of balloon aortic valvuloplasty in high-risk or inoperable patients. JACC Cardiovasc Interv. 2010;3:1150-1156.

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From the Section of Cardiology, Cardiac Catheterization Laboratory, The University of Chicago, Chicago, Illinois.

Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. They report no conflicts of interest regarding the content herein.

Address for correspondence: Atman P. Shah, MD, FACC, FSCAI, Clinical Director, Section of Cardiology, Co-Director, Cardiac Catheterization Laboratory, Associate Professor of Medicine, The University of Chicago, Chicago, IL 60637. Email: ashah@bsd.uchicago.edu