Old Dog, New Tricks: Redefining the Role for Balloon Aortic Valvuloplasty in the Transcatheter Aortic Valve Replacement Era

The recent publication of the Placement of Aortic Transcatheter Valves (PARTNER) trial and subsequent FDA approval of the Edwards Sapien balloon-expandable transcatheter aortic valve replacement (TAVR) system have shed new light on the treatment of aortic stenosis in patients deemed either at extreme risk (“inoperable”) or at high risk for open surgical aortic valve replacement (AVR). Previously, the role of balloon aortic valvuloplasty (BAV) in patients with aortic stenosis was limited to symptom palliation or as a bridge to surgical AVR.¹ Although an established procedure, BAV was not commonly performed as the results are not durable and the long-term mortality following BAV remains poor.²

With the PARTNER trial experience and the subsequent commercial release of the Edwards Sapien transcatheter aortic valve system, there has been a resurgence in the use of BAV in patients considered inoperable or at high surgical risk. In the pivotal PARTNER trial, BAV was performed as part of standard therapy in 84% of 179 inoperable subjects who were compared to those undergoing TAVR.³ Interestingly, 21 of these patients initially deemed inoperable successfully underwent surgical AVR, TAVR, or conduit placement after being bridged with BAV. Furthermore, in the standard therapy cohort, those undergoing BAV along with medical therapy had lower mortality at 3 months as compared to those who did not receive BAV,⁴ although this nonrandomized comparison is likely confounded by selection bias.

In this issue of the Journal of Invasive Cardiology, Daly et al examined their single-center BAV experience in 64 patients.⁵ They reported a 97% survival rate to hospital discharge and a 13% 30-day mortality rate. The 2 patients who did not survive until hospital discharge were noted to have cardiogenic shock prior to BAV.  In this analysis, they identified pre-BAV NYHA Class >II, left ventricular ejection fraction <45%, and a transaortic peak gradient of <80 mm Hg as multivariate predictors of mortality.  The indications for BAV in this study included symptom palliation in 44 patients and as a bridge to potential AVR (either surgical or transcatheter) in 15 patients. Among 59 patients evaluated at 1 month, only 8 ended up with either surgical or transcatheter AVR. Furthermore, only 1 of 44 patients in whom BAV was performed for symptom palliation eventually received an aortic valve.

What is striking about this analysis, albeit in a relatively small number of patients, is that despite clinical re-assessment within 30 days following BAV, the majority of patients post BAV did not go on to receive a more definitive treatment for their disease process. While the reason for this remains unclear, the authors do mention that some patients declined further treatment due to “frailty, comorbidity, and satisfaction with the improvement achieved by BAV alone.”

The lack of long-term efficacy of BAV was well established in the pre-TAVR era. However, procedural improvements over time, including initiation of rapid pacing during balloon inflations, smaller profile balloons, and the use of closure devices for vascular access, have improved the safety profile of the procedure. While BAV does not appear to alter the natural history of the disease process, its role in the TAVR era deserves further consideration. Drawing from the analysis by Daly et al, it appears that in patients in whom the purpose of BAV is to provide symptom palliation, BAV is unlikely to alter the clinical decision-making process toward a more definitive form of treatment because of factors such as age, frailty, and other comorbid conditions. Furthermore, even in patients who are considered potential candidates for AVR, fewer than half progressed to either surgical or transcatheter AVR, consistent with previous reports.⁶

The 2008 Focused Update to the American College of Cardiology/American Heart Association (ACC/AHA) Guidelines on Valvular Heart Disease address the fact that BAV is not a substitute for AVR, and that the role for BAV should be limited to serving as a bridge to surgery in those with compromised hemodynamic status (Class IIb) or as a method for palliation of symptoms in those who are not candidates for AVR (Class IIb).⁷ With the commercial release of the Edwards Sapien transcatheter aortic valve system and increasing availability of TAVR, it is likely that the recent increase in the utilization of BAV will be blunted. Patients previously bridged into the trial with BAV might proceed more directly to TAVR. However, it is also clear that many patients in the PARTNER trial (~30%) died within 1 year of TAVR despite successful therapy of their aortic stenosis. An important challenge for practitioners of this new transcatheter therapy will be to better define the relative role for TAVR in extreme-risk patients as compared to the role of palliative BAV in patients who are unlikely to gain a survival benefit despite successful TAVR due to other life-threatening comorbid conditions.

References

1. Brady ST, Davis CA, Kussmaul WG, et al. Percutaneous aortic balloon valvuloplasty in octogenarians: morbidity and mortality. Ann Intern Med. 1989;110(10):761-766.
2. Block PC, Palacios IF. Clinical and hemodynamic follow-up after percutaneous aortic valvuloplasty in the elderly. Am J Cardiol. 1988;62(10 Pt 1):760-763.
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(17):1597-1607.
4. Leon MB, Smith CR, Tuczu EM. Correspondence: the author’s reply. N Engl J Med. 2011;364;179-181.
5. Daly MJ, Monaghan M, Hamilton A, et al.  Short-term efficacy of palliative balloon aortic valvuloplasty in selected patients with high operative risk.  J Invasive Cardiol. 2012;24(2):58-62.
6. Saia F, Marrozzini C, Moretti C, et al. The role of percutaneous balloon aortic valvuloplasty as a bridge for transcatheter aortic valve implantation. Eurointervention. 2011;7(6):723-729.
7. Bonow RO, Carabello BA, Chatterjee KA, et al. 2008 focused update incorporated into the ACC/AHA 2006 guidelines for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines. J Am Coll Cardiol. 2008;52(13): E1-E142.

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From the Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
Disclosure: The authors have completed and returned the ICMJE Form for Disclosure of Potential Conflicts of Interest. The authors report no conflicts of interest regarding the content herein. Dr. Herrmann is a consultant for St. Jude Medical and has received grants/honoraria from Edwards Lifesciences, Inc.
Address for correspondence: Howard C. Herrmann, MD, University of Pennsylvania, Cardiology, 9038 Gates Pavilion, 3400 Spruce Street, Philadelphia, PA 19104. Email: Howard.Herrmann@uphs.upenn.edu