Bailout From Sinus Jailing: In-Series TAVR-in-TAVR to Avoid Coronary Flow Obstruction.

Redo transcatheter aortic valve replacement (TAVR) may pose the risk of coronary flow obstruction. We report 2 cases of severe TAVR regurgitation due to different physiopathological mechanisms in which TAVR-in-TAVR could be at high risk for sinus sequestration. Both cases were successfully treated by in-series implantation of a second transcatheter heart valve, thus avoiding sinus sequestration. (Level of Difficulty: Intermediate.).

Introduction

As indications for transcatheter aortic valve replacement (TAVR) are expanding to include younger patients with life expectancy exceeding transcatheter heart valve (THV) durability, TAVR-in-TAVR procedures are increasingly being performed (1). However, depending on the patient’s anatomy and the type of THV implanted, a “redo TAVR” may pose a high risk of coronary flow obstruction due to sinus of Valsalva sequestration, a complication characterized by impairment of blood flow to the sinus and, consequently, to the coronaries (2). Sinus sequestration may occur after redo TAVR if the degenerated THV leaflets are pushed against the sinotubular junction (STJ) and are maintained in an open position by the new THV, thus preventing perfusion of the sinuses of Valsalva (3).

Learning Objectives

To recognize the mechanism for underlying risk of coronary flow obstruction due to sinus of Valsalva sequestration during TAVR-in-TAVR.

To identify anatomic characteristics on pre-procedural CT scan that place a patient at high risk for sinus of Valsalva sequestration.

To manage patients with regurgitant degenerated THV who are at high risk for coronary flow obstruction during the TAVR-in-TAVR procedure.

Herein we present 2 successful cases of TAVR-in-TAVR at high risk for sinus sequestration treated by implantation of a second device below the nadir of the leaflets of the first THV, thus preserving the motion of the degenerated TAVR leaflets and sinus perfusion.

Case 1

An 81-year-old man who had undergone TAVR with the ACURATE neo L aortic valve (Boston Scientific, Marlborough, Massachusetts) in 2017 was admitted to our intensive care unit 3 years later for cardiogenic shock.

Transesophageal echocardiography showed severe aortic regurgitation due to leaflet tearing following untreated infective endocarditis. Because the patient’s clinical status was declining despite inotropic support, after 3 negative blood cultures a TAVR-in-TAVR was planned after discussion within the local heart team. Pre-TAVR computed tomography (CT) showed THV commissure level (area below which a pericardial cylinder is created when the leaflets are tilted up) above the STJ and a narrow valve to STJ distance posing a risk of coronary obstruction due to sinus of Valsalva sequestration (Figures 1A and 1B) (2).

Figure 1

Procedural Planning and Post-Procedural Evaluation in Case 1

(A) Pre-TAVR CT scan showing TAV commissure level (red dashed line) above the STJ (yellow dashed line) in both the left coronary sinus (LCS) and right coronary sinus (RCS). (B) Distance between the THV (red dashed line) and STJ is only “virtual” in both LCS and RCS. (C, D) Schematic illustrations of procedural planning. Red × and green × indicate first and second implanted THV commissure level, respectively. (E to G) Post-TAVR CT scan confirming coronary patency (E) and in-series leaflet positions and patency of both the left coronary artery (LCA) and right coronary artery (RCA) (F, G). Red × indicates ACURATE neo leaflets. Green × indicates MyVal leaflets. CT = computed tomography; STJ = sinotubular junction; TAV = transcatheter aortic valve; TAVR = transcatheter aortic valve replacement; THV = transcatheter aortic heart valve.

Because the mechanism of valve failure was aortic regurgitation and not stenosis, there was no need to hold the degenerated TAVR leaflets in a fixed open position with a new THV but only to reduce the central regurgitant volume from returning to the left ventricular cavity. In order to avoid sinus sequestration by pushing the leaflets of the first implanted THV against the STJ, the THV with the lowest height available on the market was chosen for TAVR-in-TAVR, aiming to implant the new THV completely below the nadir of the leaflets of the degenerated ACURATE neo (Figures 1C and 1D). Despite the impact on durability of the second implanted THV due to the regurgitant jet impacting on the cusp at each cardiac cycle, which cannot be estimated, the procedure was performed because of the patient’s rapidly degenerating clinical status and because the procedure could serve as a bridge to complete recovery.

The procedure was performed under general anesthesia and transesophageal echocardiographic guidance, with the coronaries protected by guidewires and undeployed stents. The balloon-expandable MyVal 26-mm valve (body height 18.85 mm; Meril, Vapi, India) was implanted within the ACURATE neo stent frame (height 19.5 mm). Hemodynamic evaluation showed no transvalvular gradient or paravalvular leak (PVL). Coronary patency was confirmed by final angiography and post-TAVR CT scan (Figures 1E to 1G, Video 1). Due to a theoretically higher risk of leaflet thrombosis associated with in-series TAVR-in-TAVR and given the low bleeding risk (HAS-BLED [Hypertension, Abnormal Renal/Liver Function, Stroke History, Bleeding Predisposition, Labile INR, Elderly Age, Drugs/Alcohol Use] score: 2), the patient was discharged home on oral anticoagulation. At 1-month follow-up, good performance of the implanted THV (transprosthetic mean gradient: 7 mm Hg; no PVL) and overall good patient clinical status (New York Heart Association functional class II; Canadian Cardiovascular Society class I) were noted.

Case 2

An 80-year-old man who 1 year earlier at another center had undergone TAVR with an Evolut R 26-mm valve (Medtronic Inc., Minneapolis, Minnesota) complicated by aortic migration leading to severe PVL was admitted for refractory heart failure 10 months after the original procedure. After evaluation by the heart team, the patient was deemed at very high risk for surgery (Society of Thoracic Surgeons risk score: 9.4%), and TAVR-in-TAVR was planned. Pre-TAVR CT scan showed a valve to STJ distance in the right coronary sinus of 0.2 mm (safety cut-off >2.0 mm) and a neocommissure level above the STJ posing a risk of coronary obstruction by sinus of Valsalva sequestration (Figures 2A and 2B) (2).

Figure 2

Procedural Planning and Post-Procedural Evaluation in Case 2

(A) Pre-TAVR CT scan showing a TAV commissure level (red dashed line) above the STJ (yellow dashed line), particularly in the right coronary sinus (RCS). (B) Distance between the THV (red dashed line) and STJ is 0.2 mm in the RCS, but is acceptable (>2.0 mm) in the LCS and noncoronary sinus. (C, D) Schematic illustrations of procedural planning. Red andgreen × indicate first and second implanted THV commissure level, respectively. (E to G) Post-TAVR CT scan confirming coronary patency (E) and in-series leaflet positions and patency of both the left coronary artery (LCA) and right coronary artery (RCA) (F, G). Red × indicates Evolut R leaflets. Green × indicates Lotus leaflets. Abbreviations as in Figure 1.

As in case 1, a second THV implant below the nadir of the leaflets of the first implanted device was planned. Because the Evolut R had migrated in the aorta, there was sufficient room (distance from virtual basal ring to leaflet nadir: 20.5 mm) to implant a 23-mm Lotus (Boston Scientific), a fully repositionable device with a low PVL rate (frame height: 19 mm) (Figures 2C and 2D). The Lotus, when implanted in the anatomically correct position, sealed the PVL without interfering with the Evolut R leaflets. After Lotus deployment, selective angiography confirmed patency of the right coronary artery before final release. Final aortic root angiography and post-TAVR CT scan confirmed coronary patency without sinus jailing (Figures 2E to 2G, Video 2). As in case 1, the patient was discharged home on oral anticoagulation. One-month follow-up confirmed good hemodynamic results (transprosthetic mean gradient: 9 mm Hg; trivial PVL) and good patient clinical status (New York Heart Association functional class II; Canadian Cardiovascular Society class I).

Discussion

When planning TAVR-in-TAVR, the risk of coronary flow obstruction should be carefully evaluated, especially in patients with low STJ and high THV commissures. In the reported cases, in order to avoid sinus sequestration and because the first THV presented with severe regurgitation without stenosis, we opted to implant a second intra-annular device below the first THV leaflet nadir, resulting in 2 valves in series.

In case 1, due to the high position of the supra-annular leaflets of the ACURATE neo, we were able to implant the MyVal, which has the lowest frame height available, within the first THV stent frame and below the nadir of the leaflets. In case 2, due to excessive aortic displacement of the implanted Evolut R, anatomically correct positioning of the Lotus resulted in PVL sealing.

In both cases, a tailored approach resulting in “in-series” THV-in-THV was successful in treating severe regurgitation, regardless of physiopathological mechanism, and avoiding sinus jailing with coronary flow obstruction. Of note, this approach is safe and feasible only in cases of regurgitant degenerated THV. To treat THV stenosis, the degenerated leaflets should be maintained in an open position by the second implanted device. To the best of our knowledge, we report the first 2 cases in which this safe and effective technique has been applied.

Funding Support and Author Disclosures

The performance of this study was supported exclusively by internal institutional funds. Drs. Bedogni and De Marco are proctors for Medtronic and Boston Scientific. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.