Asymptomatic aortic stenosis: management revisited

Aortic stenosis (AS) is common and is the commonest reason for valve surgery in the Western hemisphere. Calcific or a degenerative process is the most common cause of this pathological process and increases with aging population. The current guidelines recommend aortic valve replacement (AVR) only for symptoms or LV dysfunction unless a concomitant cardiac surgery is planned There are no randomized studies to guide therapy. AVR is forbidden by guidelines in severe AS patients with no symptoms. The guidelines are based on an analysis of natural history studies of AS and risk and durability of AVR. We will analyze the basis of current recommendations, unreliability of symptoms for such an important decision and more contemporary data on the natural and unnatural history of asymptomatic aortic stenosis. Based on these data, we recommend that asymptomatic AS should not be a class III recommendation for AVR and surgical options should be considered in most of severe AS patients with high risk profiles.     

Transcatheter aortic valve implantation using direct aortic access: first procedures in Poland

Transcatheter aortic valve implantation (TAVI) is an alternative option for the treatment of severe aortic stenosis in patients carrying an elevated operative risk of conventional surgical aortic valve replacement (AVR). Recently, data from randomised clinical trials confirmed superiority of TAVI when compared with the conservative treatment in inoperable patients, and its non-inferiority when compared with AVR in a high-risk population. Transfemoral vascular access remains the preferred route for delivering the bioprosthesis. However, in a significant proportion of patients, the presence of severe iliac-femoral arteriopathy or small vessel diameter render the transfemoral approach unusable. In this article, we report the first Polish experience of two successful TAVI procedures with bioprostheses (both balloon- and self-expandable) delivered using direct aortic access.     

Stroke associated with surgical and transcatheter treatment of aortic stenosis: a comprehensive review

Stroke is a potential complication of treating patients with aortic stenosis via surgical aortic valve replacement (AVR), transcatheter aortic valve replacement (TAVR), and balloon aortic valvuloplasty. Because there are limited and heterogeneous data on the incidence, risk factors, and outcomes of stroke among patients being treated for aortic stenosis, we performed a comprehensive review of the literature. The risk of stroke after AVR in the general population is approximately 1.5%, and the risk is increased (to approximately 2% to 4%) in older and higher-risk patients. Strokes were reported in 1.5% to 6% of patients treated with TAVR, and in the only randomized trial of AVR versus TAVR, there was an increased risk of 30-day strokes (minor and major strokes and transient ischemic attacks) with TAVR (5.5% vs. 2.4%, p = 0.04).     

Outcomes of patients with severe aortic stenosis at high surgical risk evaluated in a trial of transcatheter aortic valve implantation

Recent randomized clinical trials have demonstrated that transcatheter aortic valve implantation (TAVI) reduces mortality in high-risk patients with aortic stenosis who are not candidates for aortic valve replacement (AVR). In similar patients who are acceptable candidates for AVR, TAVI provides equivalent outcomes to AVR. In this study, 900 patients with severe aortic stenosis at high surgical risk were evaluated as possible candidates for TAVI. Of these, 595 (66.1%) had neither TAVI nor AVR and constituted the medical arm. In addition to the best available conservative care, 345 patients (39.3%) in this group had balloon aortic valvuloplasty. The AVR arm consisted of 146 patients (16.2%) and the TAVI arm of 159 patients (17.6%). The AVR group had significantly lower clinical risk compared to the medical and TAVI groups, with lower mean age, Society of Thoracic Surgeons score, and logistic European System for Cardiac Operative Risk Evaluation score. Patients in the medical and balloon aortic valvuloplasty group had significantly higher B-type natriuretic peptide levels compared to those in the AVR and TAVI groups and had, on average, lower ejection fractions. The medical and balloon aortic valvuloplasty group was followed for a median of 206 days; the mortality rate was 46.6% (n = 277). The AVR group was followed for 628 days; 39 patients died (26.7%). In 399 days of follow-up, the mortality rate in the TAVI group was 30.8% (n = 49). In conclusion, patients with severe AS who did not undergo TAVI or AVR had high mortality. In properly selected patients, TAVI and AVR improve outcomes. Renal failure is the strongest correlate for adverse outcomes, irrespective of treatment group.     

Our experience with surgical minimally invasive aortic valve replacement

BackgroundIn the context of the development of modern cardiac valve interventional methods (TAVI, TMVI, MitraClip), miniinvasivity in cardiac surgery is becoming increasingly important. An alternative approach to complete sternotomy in isolated aortic valve replacement (AVR) is access from anterior thoracotomy or upper ministernotomy. In CKTCH Brno, is performed an isolated aortic valve replacement (AVR) from the upper hemisternotomy (UHS) from 2013 onwards.MethodsBetween 2013 and 2016, isolated AVR was perfomed in our institution 666 patients. Full median sternotomy approach was used in 565 patients, minimally invasive approach (UHS) in 101 patients. In the ministernotomy group, classical biological or mechanical prosthesis was implanted in 55 patients; in 46 patients we used rapid deployment (sutureless) bioprosthesis Sorin Perceval S. In our study we compare the results of full sternotomy a hemisternotomy approach and also describe our surgical technique of minimally invasive aortic valve replacement.ResultsWe registered gradual increase in minimally invasive AVR between 2013 and 2016 (9 patients in 2013, 59 patients in 2016). The combined hospitalization and 30-day mortality was 0.53% (3 patients) in the full sternotomy group and 0.99% (1 patient) in the ministernotomy group. In the most risky patients, we indicated ministernotomy with implantation of rapid deployment bioprosthesis (Euroscore II. 3,0 vs. 1,6 in the group of patients with full sternotomy AVR). As published, we confirmed longer aortic cross clamp time (AoX) and lenght of extracorporal circulation (ECC) in the patients with ministernotomy and implantation of sutured aortic prosthesis in comparison with full sternotomy AVR. Conversely, shorter AoX time and ECC time was observed in patients with rapid deployment prosthesis implantation from ministernotomy. We also recorded smaller postoperative blood loss in patients with ministernotomy apporach. The other monitored parameter were comparable.ConclusionIn this study we describe our technique and results of minimally invasive aortic valve replacement in our institution. Based on our results, we evaluate this technique as safe and well reproducible.     

Aortic valve replacement for patients with mild to moderate aortic stenosis undergoing coronary artery bypass surgery

Aortic valve replacement (AVR) is not normally recommended in asymptomatic patients, even if aortic stenosis is severe. However, as the population ages, an increasing number of patients with mild or moderate aortic stenosis will require coronary artery bypass grafting (CABG). In these cases, risk of "prophylactic" AVR needs to be weighed against risks of subsequent worsening of the mildly or moderately diseased aortic valve. If unoperated, aortic stenosis will worsen at an average of 6-8 mmHg per year (-0.1 cm2/year valve area), and one-quarter of such patients will require late AVR with a high operative mortality (14-24%). If AVR is performed at the time of CABG, operative risk is increased only slightly (from 1-3% to 2-6%), as are late mortality (1-2% per year) and morbidity (1-2% per year), mainly from hemorrhagic complications. Intrinsic gradients of most prosthetic valves are sufficiently low that even patients with low aortic valve gradients are likely to derive hemodynamic benefit from AVR. Thus, if there is a measurable (>20-25 mmHg) gradient across the aortic valve in a patient who requires CABG, the patient is at considerable risk for developing symptomatic aortic stenosis prior to reaching the end of expected benefit from CABG; in this case AVR should be considered. It may be reasonable in patients with very mild gradients (<25 mmHg) to defer aortic valve surgery; however, it should be noted that aortic stenosis progression is generally more rapid when the initial gradient is small.     

Percutaneous aortic valve in severe valvular regurgitation caused by infective endocarditis

Recently, the feasibility and safety of percutaneous aortic valve replacement (PAVR) have been reported in the treatment of degenerative aortic valve stenosis in patients at high-risk for surgical aortic valve replacement (AVR). However, so far this therapy has been limited to patients with severe stenosis of the native valve. We report the case of an 84 year old patient with severe aortic regurgitation caused by infective endocarditis who was successfully treated by implantation of a CoreValve (CoreValve Inc, Irvine. Calif) prosthesis with a totally percutaneous approach.     

Cardiac transplantation in adults with aortic valve disease with focus on the bicuspid aortic valve

The frequency of congenitally bicuspid aortic valves in patients having cardiac transplantation (CT) is unknown. We reviewed 243 explanted hearts in patients having CT at Baylor University Medical Center, Dallas from June 1997 through November 2011 to determine the frequency of a bicuspid aortic valve in this population. Of the 243 explanted hearts, 7 (2.9%) were found to have a congenitally bicuspid aortic valve: 3 had severe aortic valve stenosis and before CT had had the aortic valve replaced; the other 4 had normally functioning bicuspid valves and underwent CT for cardiomyopathy (ischemic in 1, idiopathic in 2, and hypertrophic in 1). Review of previously published reports of CT and aortic valve disease disclosed that 4 patients had had aortic valve replacement (AVR) from 2 to 8 years before CT, 3 had AVR or aortic valve repair of the donor heart at the time of CT, and 4 had AVR or transcatheter aortic valve implantation from 1 to 14 years after CT. Some of these aortic valve replacements, before, at the time of, or after CT were in patients with congenitally bicuspid aortic valves. In conclusion, congenitally bicuspid aortic valves were found in 7 of 243 explanted hearts in patients having CT at a single medical center in a 14-year period: 4 had functioned normally and 3 were severely stenotic. Previous reports of patients having AVR or repair before, during, and after CT were reviewed.     

Transcatheter aortic valve implantation in patient with cardiogenic shock

Transcatheter aortic valve implantation (TAVI) is an established treatment option in patients with symptomatic severe aortic stenosis, who are at high or intermediate risk for surgical aortic valve replacement. The vast majority of TAVI are performed on patients without acute decompensated heart failure. In this case report we present the successful TAVI in a patient with a cardiogenic shock.     

Considerations in antithrombotic therapy among patients undergoing transcatheter aortic valve implantation

Aortic stenosis (AS) accounts for the majority of valvular abnormalities requiring surgical intervention. Platelet dysfunction has been demonstrated among patients with severe aortic stenosis which may predispose patients to bleeding or ischemic events. Surgical aortic valve replacement (AVR) is the standard therapy for severe symptomatic AS; however, a number of patients have very high or prohibitive surgical risk. Transcatheter aortic valve implantation (TAVI) has been shown to be superior to medical therapy among inoperable patients and non-inferior to AVR in patients with high surgical risk. In comparison to AVR, TAVI has been associated with a higher incidence of ischemic cerebrovascular events, conduction abnormalities necessitating permanent pacemaker placement, and vascular complications. Current practice guidelines recommend dual antiplatelet therapy (DAPT) following TAVI using a combination of low dose aspirin and clopidogrel for 3–6 months. This regimen may be adjusted in patients with clinical bleeding events or indications for concomitant systemic anticoagulation. Recent and ongoing trials aim to clarify the optimum antithrombotic regimen and duration of therapy following TAVI. Collectively, early studies have not revealed additional benefit of adding clopidogrel to aspirin therapy in regards to reducing ischemic events, but have shown a trend towards increase in major bleeding. TAVI has proven successful, and as its breadth of utility is expanded, further studies are needed to define optimum antithrombotic therapy following TAVI. This article will review the current data for antiplatelet and anticoagulant therapy following TAVI.     

Long-term risk of aortic events following aortic valve replacement in patients with bicuspid aortic valves

Bicuspid aortic valve (BAV) is associated with ascending aortopathy predisposing to aneurysmal dilatation and dissection, even after successful aortic valve replacement (AVR). There is, however, scant evidence on which to make recommendations for prophylactic replacement of the ascending aorta at the time of AVR. The medical records of patients who underwent AVR for BAV without aortic replacement or repair from 1960 to 1995 were reviewed. Follow-up was by review of the medical record and postal questionnaire. Among 1,286 patients, the mean age at operation was 58 ± 14 years. During the follow-up interval (median 12 years, range 0 to 38), there were 13 documented aortic dissections (1%), 11 ascending aortic replacements (0.9%), and 127 documented cases of progressive aortic enlargement (9.9%). Fifteen-year freedom from aortic dissection, enlargement, or replacement was 89% (95% confidence interval [CI] 87% to 91%) and was lower in patients with documented aortic enlargement at the time of AVR (85%, 95% CI 81% to 89%) compared to those whose aortic dimensions were normal (93%, 95% CI 90% to 96%) (p = 0.001). Multivariate predictors of aortic complications included interval (subsequent) AVR (hazard ratio [HR] 3.5, 95% CI 2.3 to 5.4, p <0.001), concomitant coronary artery bypass grafting (HR 2.6, 95% CI 1.7 to 4.0, p <0.001), enlarged aorta (HR 1.8, 95% CI 1.3 to 2.6, p = 0.001), and history of tobacco abuse (HR 1.8, 95% CI 1.2 to 2.6, p = 0.003). Aortic dilatation did not predict mortality. In conclusion, despite a true risk for aortic events after AVR for BAV, the occurrence of aortic dissection was low. Any incremental surgical risk imposed by prophylactic replacement of the ascending aorta must be equally low.     

Infective endocarditis following transcatheter aortic valve implantation

Trans-catheter aortic valve implantation (TAVI) has recently emerged as a less invasive alternative to surgical aortic valve replacement (SAVR) in high risk patients. Although several procedures have been performed worldwide, infective endocarditis (IE) has been reported to be a rare TAVI complication, nevertheless if IE occurs it represents a life-threatening condition and treatment is challenging. TAVI-IE are thus normally treated conservatively by targeted antibiotic therapy with a high reported mortality (40%). Surgical explant represent the definitive strategy but, the intervention is at a high risk (risk of complication 87%, with an in hospital mortality of about 47%). In the present paper, we report the case of a 71-year-old patient affected by an early endocarditis after TAVI (TAVI-IE) treated at our Institution by surgical explant. The case highlights a paradox: if TAVI procedures are indicated over traditional surgical valve replacement in treatment of high surgical risk patients, what should be the best management when TAVI-IE occurs in these same population of patients?     

Transcatheter aortic valve implantation under conscious sedation – the first Indian experience

Transcatheter aortic valve implantation (TAVI) is maturing strongly as an alternative to surgical aortic valve replacement (SAVR) in patients who are inoperable/high risk for open heart surgery. General anesthesia (GA) is the usual mode of anesthesia in these patients, but local anesthesia with conscious sedation (LACS) has recently been described as a safe alternative with some added advantages. We report 2 cases who were unfit for GA and were done successfully under LACS.     

Combined surgical and catheter‐based treatment of extensive thoracic aortic aneurysm and aortic valve stenosis

An extensive thoracic aortic aneurysm (TAA) is a potentially life‐threatening condition and remains a technical challenge to surgeons. Over the past decade, repair of aortic arch aneurysms has been accomplished using both hybrid (open and endovascular) and totally endovascular techniques. Thoracic endovascular aneurysm repair (TEVAR) has changed and extended management options in thoracic aorta disease, including in those patients deemed unfit or unsuitable for open surgery. Accordingly, transcatheter aortic valve replacement (TAVR) is increasingly used to treat patients with symptomatic severe aortic valve stenosis (AS) who are considered at high risk for surgical aortic valve replacement. In this report, we describe the combined surgical and catheter‐based treatment of an extensive TAA and AS. To our knowledge, this is the first report of hybrid TAA repair combined with TAVR. © 2014 Wiley Periodicals, Inc.     

Emergency balloon aortic valvuloplasty in patients with critical aortic stenosis presenting with cardiogenic shock.

This report describes 2 cases of aortic valvuloplasty performed as emergency treatment in patients with critical aortic stenosis presenting with cardiogenic shock. This procedure can be life-saving, and allows the patients to undergo further evaluation for aortic valve replacement, or other definitive treatments such as the recently developed percutaneous heart valve implantation for patients with unacceptably high surgical risk.     

Risk profile and outcomes of aortic valve replacement in octogenarians

AIM: To investigate the patient characteristics, relationship between the Logistic EuroSCORE (LES) and the observed outcomes in octogenarians who underwent surgical aortic valve replacement (AVR). METHODS: Two hundred and seventy three octogenarians underwent AVR between 1996 and 2008 at Bristol Royal Inf irmary. Demographics, acute outcomes,length of hospital stay and mortality were obtained. The LES was calculated to characterize the predicted operative risk. Two groups were def ined: LES ≥ 15 (n = 80) and LES < 15 (n = 193). RESULTS: In patients with LES ≥ 15, 30 d mortality was 14% (95% CI: 7%-23%) compared with 4% (95% CI: 2%-8%) in the LES < 15 group (P < 0.007). Despite the increase in number of operations from 1996 to 2008, the average LES did not change. Only 5% of patients had prior bypass surgery. The LES identifi ed a low risk quartile of patients with a very low mortality (4%, n = 8, P < 0.007) at 30 d. The overall surgical results for octogenarians were excellent. The low risk group had an excellent outcome and the high risk group had a poor outcome after surgical AVR. CONCLUSION: It may be better treated with transcatheter aortic valve implantation.     

Contemporary balloon aortic valvuloplasty: Changing indications and refined technique

Even if un to improve long-term prognosis, balloon aortic valvuloplasty (BAV) may be useful in selected patients with symptomatic severe aortic stenosis either as a bridge to surgical or transcatheter valve replacement (aortic valve replacement [AVR] or transcatheter aortic valve implantation [TAVI]) or as a triage strategy for patients with uncertain indications. International guidelines recommend BAV as: a “bridge” to AVR/TAVI, a “trial” in patients with undetermined symptoms, or a “bridge-to-decision” in case of comorbidities. However, in clinical practice, BAV is also used as a palliative measure to improve hemodynamics and quality of life in many patients who are excluded from AVR/TAVI. Finally, BAV is often performed during TAVI to facilitate prosthesis delivery, optimize frame expansion, or for bioprosthetic valve fracture in selected valve-in-valve procedures. Technical innovations, which allow for a mini-invasive approach via transradial access and pacing delivered through the wire, have led to a decrease in complications over time. This review focuses on contemporary BAV with a specific emphasis on new indications, innovative techniques, and specific complex patient subgroups.     

Transcatheter aortic valve replacement in elderly patients

Aortic stenosis is the most common native valve disease, affecting up to 5% of the elderly population. Surgical aortic valve replacement reduces symptoms and improves survival, and is the definitive therapy in patients with symptomatic severe aortic stenosis. However, despite the good results of classic surgery, risk is markedly increased in elderly patients with co-morbidities. Transcatheter aortic valve replacement (TAVR) allows implantation of a prosthetic heart valve within the diseased native aortic valve without the need for open heart surgery and cardiopulmonary bypass, offering a new therapeutic option to elderly patients considered at high surgical risk or with contraindications to surgery. To date, several multicenter registries and a randomized trial have confirmed the safety and efficacy of TAVR in those patients. In this chapter, we review the background and clinical applications of TAVR in elderly patients.     

Transcatheter aortic valve implantation

Aortic stenosis is the most important valvular heart disease affecting the elderly population. Surgical aortic valve replacement is the mainstay of treatment, although a substantial number of patients are considered high risk for surgery. Many of these patients do not undergo surgery and have poor outcomes from medically treated symptomatic, severe aortic stenosis. Transcatheter aortic valve implantation (TAVI) provides a promising treatment option for some of these patients. Several devices are under investigation. The Edwards Sapien valve (Edwards Lifesciences, Irvine, CA) and the CoreValve (Medtronic, Minneapolis, MN) have the largest human experience to date. Initial data suggest that these devices have an acceptable safety profile and provide excellent hemodynamic relief of aortic stenosis. The Edwards Sapien valve is currently under investigation in the United States in the PARTNER (Placement of Aortic Transcatheter Valve) trial in high-risk surgical or inoperable patients; TAVI is available for clinical use in both Canada and Europe. TAVI is not used in low- or intermediate-risk surgical patients; however, future studies may prove its applicability in these subsets. The major complications of TAVI include access site-related problems and device malpositioning/migration. There are several new-generation prosthetic valves and delivery systems designed to be low profile and repositionable. Technical advances and refinement of the implantation methods may make TAVI even safer and ultimately a better treatment option, not only for patients with high surgical risk but also for those with moderate or low risk.     

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.