Can We Use Valve-In-Valve Transcatheter Aortic Valve Replacement in an Unstable Patient?

After the publication of the PARTNER trial, transcatheter aortic valve replacement (TAVR) has become an option for treatment of patients with severe aortic stenosis (AS) who are at high risk of undergoing surgery.¹ Since then, several off-label indications for TAVR have emerged. TAVR has been shown to be feasible in patients with pure aortic valve insufficiency (AI) who are high-risk candidates for surgery² and as a valve-in-valve procedure either over a previous TAVR or over a previously implanted bioprosthetic valve. 

Valve-in-valve after TAVR. Paravalvular leak is a recognized complication of TAVR, and is most commonly caused by malpositioning of the prosthesis. Once deployed, it is not possible to reposition the prosthesis. Hence, the transcatheter valve-in-valve (TV-in-TV) technique has been described in cases of acute AI due to malpositioning of the first prosthesis.^3-5 A recent study published from the PARTNER trial showed that TV-in-TV was performed in 2.5% of patients and was associated with a higher incidence of conduction abnormalities, pacemaker implantation, and increased cardiovascular mortality at 1 year.³ However, most of the TV-in-TVs in this study were done in an acute, emergent setting during or immediately after the first TAVR. Other studies^4,5 have shown satisfactory outcomes and no clinically significant hemodynamic gradients at long-term follow-up in patients undergoing TV-in-TV compared to standard TAVR.

Valve-in-valve after surgical bioprosthetic valve. Similarly, TAVR has been performed in patients with failed surgically implanted bioprosthetic valves who are at high risk for re-operation. A study published in 2012 from the Global Valve-in-Valve registry included 202 patients undergoing TAVR for failed bioprosthetic valves.⁶ The mode of failure was stenosis in 42%, regurgitation in 34%, and combined stenosis and regurgitation in 24% of patients. The procedure was successfully performed in 93% of patients and the most common adverse outcomes were device malposition (15%) and ostial coronary obstruction (3.5%). There were high peak and mean gradients of 28.4 and 15.9 mm Hg, respectively; however, the clinical significance of this is unclear. High gradients are believed to be due to underexpansion of the transcatheter valve due to the relatively undilatable sewing ring of the bioprosthetic valve.^6,7 Hence, use of this technique in small <21 mm bioprosthetic valves may result in significantly high residual gradients.^7,8 The size of the valve selected for TAVR depends upon the internal diameter of the bioprosthetic valve, mechanism of failure (regurgitation vs stenosis), and location of calcification or pannus.⁷ AI appears to be absent or mild in cases of valve-in-valve over bioprosthetic valves, possibly because the circular sewing ring of the bioprosthesis facilitates intervalvular sealing.⁷ Currently, valve-in-valve TAVR over a bioprosthetic valve is done electively in hemodynamically stable patients.

The case series published in the current issue of the Journal of Invasive Cardiology by Fudim et al⁹ details 2 cases of severe AI due to failed degenerated bioprosthetic valves causing acute congestive heart failure (CHF) and cardiogenic shock. Since both these patients were deemed high risk for surgery, the therapeutic options were limited and TAVR was performed. In both cases, TAVR was successful with reductions in pulmonary pressures, but was complicated by high-grade heart block requiring a pacemaker. Although patients with cardiogenic shock or those on inotropic support were excluded from the PARTNER trial, the TV-in-TV procedures performed after device malpositioning leading to acute severe AI were mostly done in an emergent setting with likely hemodynamic compromise.³ It is therefore logical to extend this scenario in patients with failed bioprosthetic valves causing acute severe AI. Moreover, the effect of the annulus of the bioprosthesis in reducing post-TAVR AI⁷ makes it even more attractive to use TAVR in this population. The authors demonstrate feasibility and success of this procedure in 2 such patients at their institution. With AI causing hemodynamic instability in a patient with an acutely failing bioprosthetic valve, the therapeutic options are limited and TAVR may be implemented as a salvage procedure after careful patient selection. It is important to bear in mind etiology of the prosthetic failure, nature of the prosthetic failure, size of the implanted valve, and anatomy of the aorta and peripheral vascular system prior to using TAVR in these patients.

References

1. 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.
2. Roy DA, Schaefer U, Guetta V, et al. Transcatheter aortic valve implantation for pure severe native aortic valve regurgitation. J Am Coll Cardiol. 2013;61(15):1577-1584.
3. Makkar RR, Jilaihawi H, Chakravarty T, et al. Determinants and outcomes of acute transcatheter valve-in-valve therapy or embolization: a study of multiple valve implants in the U.S. PARTNER trial (Placement of AoRTic TraNscathetER Valve Trial Edwards SAPIEN Transcatheter Heart Valve). J Am Coll Cardiol. 2013;62(5):418-430.
4. Toggweiler S, Wood DA, Rodes-Cabau J, et al. Transcatheter valve-in-valve implantation for failed balloon-expandable transcatheter aortic valves. JACC Cardiovasc Interv. 2012;5(5):571-577.
5. Ussia GP, Barbanti M, Ramondo A, et al. The valve-in-valve technique for treatment of aortic bioprosthesis malposition an analysis of incidence and 1-year clinical outcomes from the Italian CoreValve registry. J Am Coll Cardiol. 2011;57(9):1062-1068.
6. Dvir D, Webb J, Brecker S, et al. Transcatheter aortic valve replacement for degenerative bioprosthetic surgical valves: results from the global valve-in-valve registry. Circulation. 2012;126(19):2335-2344.
7. Gurvitch R, Cheung A, Ye J, et al. Transcatheter valve-in-valve implantation for failed surgical bioprosthetic valves. J Am Coll Cardiol. 2011;58(21):2196-2209.nbsp;
8. Ferrari E. Transcatheter aortic “valve-in-valve” for degenerated bioprostheses: choosing the right TAVI valve. Ann Cardiothorac Surg. 2012;1(2):260-262.
9. Fudim M, Markley RR, Robbins MA, et al. Transcatheter aortic valve replacement for aortic bioprosthetic valve failure with cardiogenic shock. J Invasive Cardiol. 2013;25(11):625-626.