The impact of mitral stenosis on outcomes of aortic valve stenosis patient undergoing surgical aortic valve replacement or transcatheter aortic valve replacement

Background

The concomitant presence of mitral stenosis (MS) in the setting of symptomatic aortic stenosis represent a clinical challenge. Little is known regarding the outcome of mitral stenosis (MS) patients undergoing transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR). Therefore, we sought to study the outcome of MS patients undergoing aortic valve replacement (AVR).

Method

Using weighted data from the National Inpatient Sample (NIS) database between 2011 and 2014, we identified patients who were diagnosed with MS. Patients who had undergone TAVR as a primary procedure were identified and compared to patients who had SAVR. Univariate and multivariate logistic regression analysis were performed for the outcomes of in‐hospital mortality, length of stay (LOS), blood transfusion, postprocedural hemorrhage, vascular, cardiac and respiratory complications, permanent pacemaker placement (PPM), postprocedural stroke, acute kidney injury (AKI), and discharge to an outside facility.

Results

A total of 4524 patients were diagnosed with MS, of which 552 (12.2%) had TAVR and 3972 (87.8%) had SAVR. TAVR patients were older (79.9 vs 70.0) with more females (67.4% vs 60.0%) and African American patients (7.7% vs 7.1%) (P < 0.001). In addition, the TAVR group had more comorbidities compared to SAVR in term of coronary artery disease (CAD), congestive heart failure (CHF), chronic lung disease, hypertension (HTN), chronic kidney disease (CKD), and peripheral vascular disease (PVD) (P < 0.001 for all). Using Multivariate logistic regression, and after adjusting for potential risk factors, TAVR patients had lower in‐hospital mortality (7.9% vs 8.1% adjusted Odds Ratio [aOR], 0.615; 95% confidence interval [CI], 0.392–0.964, P = 0.034), shorter LOS. Also, TAVR patients had lower rates of cardiac and respiratory complications, PPM, AKI, and discharge to an outside facility compared with the SAVR group.

Conclusion

In patients with severe aortic stenosis and concomitant mitral stenosis, TAVR is a safe and attractive option for patients undergoing AVR with less complications compared with SAVR.

     

Future perspectives in transcatheter aortic valve implantation

Transcatheter aortic valve replacement (TAVR) constitutes a relatively new treatment option for the patients with severe symptomatic aortic stenosis. Evidence from registries and randomized control trials has underscored the value of this treatment in inoperable and high risk populations, while new developments in valve technology and TAVR enabling devices have reduced the risk of complications, simplified the procedure, and broadened the applications of this therapy. The initial promising clinical results and the potential of an effective less invasive treatment of aortic stenosis has not only created high expectations but also the need to address the pitfalls of TAVR technology. The evolving knowledge concerning the groups of patients who would benefit from this treatment, the limited long term follow-up data, the concerns about devices' long term durability, and the severity of complications remain important caveats which restrict the widespread clinical adoption of TAVR. The aim of this review article is to present the recent advances, highlight the limitations of TAVR technology, and discuss the future perspectives in this rapidly evolving field.     

Retrograde percutaneous aortic valve implantation for critical aortic stenosis.

Recently, a prosthetic aortic valve has been implanted percutaneously in several patients using an antegrade transseptal approach. This has been shown to be feasible and associated with dramatic hemodynamic improvement. We report a retrograde implantation of a percutaneous heart valve (PHV) in an 84-year-old man with critical aortic stenosis and refractory congestive heart failure after difficulties encountered with an initial antegrade approach. While attempting antegrade transseptal implantation of a PHV, the anterior leaflet of the mitral valve was tethered by the guidewire resulting in severe mitral regurgitation and pulseless electrical activity. Cardiac resuscitation was successful. Utilizing a retrograde approach, the PHV was successfully implanted in a stable position below the coronary ostia and well above the mitral valve leaflets. The aortic valve area increased from 0.55 to 1.7 cm2 with only mild paravalvular aortic regurgitation. Despite marked improvement in aortic valve function, the patient died secondary to guidewire-induced mitral valve anterior leaflet laceration, severe mitral regurgitation, and cardiogenic shock. Retrograde implantation of a PHV can be successfully performed with substantial increase in aortic valve area and an acceptable degree of aortic regurgitation. Although the retrograde approach may be associated with greater risk of vascular access site complications, it may be considerably safer by avoiding potential guidewire injury to the mitral valve. Further refinements in technique may establish the retrograde approach as the preferred means of PHV implantation in nonsurgical patients with critical aortic stenosis.     

Recent developments and controversies in transcatheter aortic valve implantation

Interventional cardiology has been revolutionised by transcatheter aortic valve implantation (TAVI), which has become established as the benchmark treatment for severe aortic stenosis in patients at high risk for surgical aortic valve replacement (AVR). Increased procedural familiarity and progression in device technology has enabled improvements to be made in complication rates, which have led to a commensurate expansion in the use of TAVI; it is now a viable alternative to AVR in patients at intermediate surgical risk, and has been used in cohorts such as those with bicuspid aortic valves or pure, severe aortic regurgitation. Given the rapid expansion in the use of TAVI, including cohorts of younger patients with fewer co‐morbidities, attention must be paid to further reducing remaining complications, such as cardiac tamponade or stroke. To this end, novel techniques and devices have been devised and trialled, with varying levels of success. Furthermore, significant work has gone into refining the technique with exploration of alternative imaging modalities, as well as alternative access routes to provide greater options for patients with challenging vascular anatomy. Whilst significant progress has been made with TAVI, areas of uncertainty remain such as the management of concomitant coronary artery disease and the optimum post‐procedure antiplatelet regimen. As such, research in this field continues apace, and is likely to continue as use of TAVI becomes more widespread. This review provides a summary of the existing evidence, as well as an overview of recent developments and contentious issues in the field of TAVI.     

The next era of transcatheter aortic valve replacement: A case illustrating the benefit of a fully re‐positionable,re‐sheathable,and retrievable prosthesis

While transcatheter aortic valve replacement (TAVR) is an accepted treatment modality in appropriately selected patients there remain modest complication rates. New TAVR devices, through novel design features, may overcome some of these complications. We present the first case of full re‐sheathing and retrieval of a Lotus Valve to facilitate a change in prosthesis size. © 2013 Wiley Periodicals, Inc.     

Contemporary application of cardiovascular hemodynamics: transcatheter aortic valve interventions

Over the past two decades, echocardiography has replaced cardiac catheterization for aortic valvular hemodynamic assessment. In recent years, however, there has been a rapid evolution of transcatheter aortic valve technology and, with its refinement, there has been the increasing recognition of the value of transcatheter hemodynamic assessment in complementing the information provided by contemporary echocardiography. With an emphasis on transcatheter hemodynamics, this article reviews the symbiotic application of these assessment modalities pertaining to contemporary transcatheter aortic valve implantation.     

Changes in mitral regurgitation after transcatheter aortic valve implantation

Objectives : To assess the acute and intermediate changes in mitral regurgitation (MR) severity after transcatheter aortic valve implantation (TAVI) with the CoreValve Revalving SystemTM (CRS). Background : Following surgical aortic valve replacement, improvement in MR is reported in 27–82% of the patients. The changes in MR severity following CRS implantation are unknown. Methods : Transthoracic echocardiography was performed in 79 consecutive patients before and after treatment, and at the first outpatient visit. Left ventricular dimensions and ejection fraction (LVEF), left atrial (LA) size, and aortic gradient were measured. MR was assessed by color flow mapping and was graded as none, mild, moderate, or severe. It was defined as organic or functional. The depth of CRS implantation was measured by angiography. Results : Post‐treatment, the mean gradient decreased from 48 ± 16 mm Hg to 9 ± 5 mm Hg (P < 0.0001). There was no significant change in the left ventricular dimensions, LA size, and LVEF. MR pretreatment was mild, moderate, or severe in 57%, 18%, and 1% of the patients, respectively. It was defined as organic in 27 patients (36%) and functional in 27 patients (36%). The degree of MR remained unchanged in 61% of the patients, improved in 17%, and worsened in 22%. MR improvement was associated with a lower baseline LVEF (P = 0.02). There was no association between the changes in MR severity and the depth of CRS implantation. Conclusions : Most patients who underwent TAVI had some degree of MR. Overall there was no change in the degree of MR post‐treatment. Patients in whom MR improved had a lower LVEF at baseline. © 2009 Wiley‐Liss, Inc.     

Transaortic transcatheter aortic valve implantation within a previous bioprosthetic aortic valve replacement

This report documents the first reported case of transaortic transcatheter aortic valve implantation (TAVI) using the CoreValve ReValving system (Medtronic CoreValve System, Luxembourg), within a previous bioprosthetic aortic valve replacement. TAVI has become a recognized percutaneous treatment for patients with severe native or bioprosthetic aortic valve stenosis. However, as the number of patients screened for TAVI increases, a number of patients are found with absolutely no option for peripheral arterial access, either from the femoral or subclavian routes. Transaortic CoreValve placement offers an alternate minimally invasive hybrid surgical/interventional technique when peripheral access is not possible. A CoreValve prosthesis was implanted via the transaortic route in an 81‐year‐old woman with severe bioprosthetic aortic valve stenosis (21 mm Mitroflow pericardial valve, peak instantaneous gradient of 99 mmHg, effective valve orifice area (EOA) of 0.3 cm², as ilio‐femoral and left subclavian angiography revealed small calibre vessels (<6 mm). Access was achieved via a mini thoracotomy via the left anterior second intercostal space. The procedure went without complication. Post procedure the patient was transferred directly to the Cardiac Care Unit for recuperation. Post procedure echocardiography showed that the TAVI was well positioned with no para‐valvular leak and a reduction in peak instantaneous gradient to 30 mmHg and an increase in EOA to 1.5 cm². She was discharged on the third post‐procedural day in sinus rhythm with a narrow QRS complex. CoreValve implantation within previous surgical bioprosthesis is now an established treatment. The transaortic approach to transcatheter implantation is a promising recent development, when due to anatomical reasons, transfemoral or subclavian TAVI is not feasible. © 2011 Wiley‐Liss, Inc.     

Difficulties with horizontal aortic root in transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) emerged to be a viable treatment option for failing bioprosthesis in the aortic position. Transfemoral approach is the most common access route for TAVI and associated with most favorable clinical outcome. However, in the presence of unfavorable aortic root anatomy, TAVI via transfemoral approach provides inadequate support for device manipulation during valve positioning, particularly performed for the indication of severe aortic regurgitation. We report our experience on TAVI utilizing CoreValve for a patient with regurgitant failing bioprosthesis with horizontal aortic root where we encountered difficulties during implantation and retrieval of valve delivery system. © 2012 Wiley Periodicals, Inc.     

Outcomes of patients with low‐pressure aortic gradient undergoing transcatheter aortic valve implantation

Background: The risk/benefit balance of transcatheter aortic valve implantation (TAVI) in patients with low‐gradient aortic stenosis (LGAS) remains to be well defined. Aim of the study was to investigate the impact of LGAS in patients undergoing TAVI. Methods: Medline, Cochrane Library, and Scopus were searched for articles reporting outcome of patients with LGAS undergoing TAVI. The primary endpoint was 12‐months all‐cause mortality and the secondary endpoint was 30‐day all‐cause mortality. Using event‐rates as dependent variable, a meta‐regression was performed to test for interaction between baseline clinical features (age, gender, diabetes mellitus, coronary artery disease, left ventricular ejection fraction (LVEF) and type of implanted valve) and transaortic gradient for the primary endpoint. Results: Eight studies with a total of 12,589 patients were included. Almost one‐third of the patients presented with LGAS (27.3%: 24.4–29.2). Median LVEF was 48% in patients with LGAS and 56% in patients with high‐gradient AS. Patients with LGAS were more likely to have diabetes mellitus, previous coronary artery disease, higher mean Logistic EuroSCORE, and lower EF. At 12 (12–16.6) months, low transaortic gradient emerged as independently associated with all‐cause death, both if evaluated as a dichotomous and continuous value (respectively OR 1.17; 1.11–1.23 and OR 1.02; 1–1.04, all CI 95%). Clinical variables, including EF did not affect this result. Conclusions: In a population of TAVI patients, LGAS appears to be independently related to dismal prognosis. © 2016 Wiley Periodicals, Inc.     

Severe intraprosthetic regurgitation and valve embolization after transcatheter aortic valve implantation

Transcatheter aortic valve implantation is a novel therapeutic approach for high‐risk patients with severe symptomatic aortic stenosis. The success rate of this new procedure is high; however, procedural complications can occur and may result in devastating outcomes. Here, we report a case of transfemoral catheter aortic valve implantation using the Edwards SAPIEN valve complicated by severe intravalvular leak due to immobile cusp associated with shock. We treated with a second valve that embolized and deployed in the descending aorta. A third valve was then deployed within the first with elimination of aortic regurgitation and immediate hemodynamic improvement. © 2012 Wiley Periodicals, Inc.     

Transcatheter aortic valve implantation without balloon predilatation

Balloon predilatation has been regarded as an essential step before implanting the self‐expandable prosthesis during transcatheter aortic valve implantation (TAVI). Recent evidence showed that without balloon predilatation, an implantation success rate of >95% could be achieved. We report two cases in which balloon predilatation was not performed initially during TAVI but eventually required it to facilitate device crossing and implantation. They illustrated the importance of case selection and alerted us the potential limitation in performing TAVI without balloon predilatation. © 2013 Wiley Periodicals, Inc.     

Valve prosthesis distortion after cardiac compression in a patient who underwent transcatheter aortic valve implantation (TAVI)

Transcatheter aortic valve implantation (TAVI) has been developed as an alternative to conventional aortic valve replacement for the treatment of symptomatic severe aortic stenosis in high‐risk patients. Nevertheless, TAVI has been associated with serious complications such as stroke, vascular injury, renal failure, and arrhythmia. Herein we describe a case of distortion of the Edward‐Sapien prosthesis (Edwards Lifesciences, USA), which was mounted on a balloon‐expandable stent, after chest compression for cardiac resuscitation in a patient who underwent TAVI for severe aortic stenosis. © 2012 Wiley Periodicals, Inc.     

Transcatheter aortic valve implantation by left subclavian access in the presence of a patent LIMA to LAD graft

We present a case of successful implantation of the Corevalve aortic bioprosthesis via the left subclavian artery in a patient with a patent internal mammary graft to the left anterior descending artery. This unusual choice of access, in the presence of adequate caliber femoral arteries, was justified by the presence of mobile thrombi in the abdominal aorta. The risk of thrombus dislodgement and subsequent major cholesterol embolization was deemed higher than the risk of coronary ischemia due to the large caliber sheath required for transcatheter aortic valve implantation. This case shows that presence of a LIMA to LAD graft is not an absolute contraindication for homolateral subclavian access and that the procedure is feasible and relatively safe provided that certain rules are followed. © 2010 Wiley‐Liss, Inc.