Survival benefit of aortic valve replacement in patients with severe aortic stenosis with low ejection fraction and low gradient with normal ejection fraction

Impact of Baseline Left Ventricular Ejection Fraction on Midterm Outcomes in Women Undergoing Transcatheter Aortic Valve Implantation: Insight from the WIN-TAVI Registry

Limited evidence exists concerning the prognostic impact of baseline left ventricular ejection fraction (LVEF) on outcomes among women undergoing transcatheter aortic valve implantation (TAVI), which we aimed to investigate in the present analysis. Patients from the Women's International Transcatheter Aortic Valve Implantation (WIN-TAVI) registry were categorized according to baseline LVEF into 3 groups: reduced (LVEF ≤40%), mildly reduced (LVEF between 41% and 49%), and preserved (LVEF ≥50%) LVEF. The primary (Valve Academic Research Consortium 2 [VARC-2]) efficacy point was defined as a composite of mortality, stroke, myocardial infarction, hospitalization for valve-related symptoms or heart failure, or valve-related dysfunction at 1 year. The primary (VARC-2) safety end point included all-cause mortality, stroke, major vascular complication, life-threatening bleeding, stage 2 to 3 acute kidney injury, coronary artery obstruction requiring intervention, or valve-related dysfunction requiring repeated procedures. A Cox regression model was performed using the preserved LVEF group as the reference. Among the 944 patients included, 764 (80.9%) exhibited preserved, 80 (8.5%) had mildly reduced, and 100 (10.6%) had reduced LVEF. The 1-year incidence of VARC-2 efficacy end point was numerically higher in patients with reduced LVEF, albeit not resulting in a significant risk difference. Notably, reduced LVEF was associated with a higher risk of the 1-year VARC-2 safety end point, still significant after adjustment (28.0% vs 19.6%, Hazard Ratio 1.78, 95% Confidence Interval 1.12- 2.82, p = 0.014). These differences were primarily driven by trends toward increased rates of all-cause mortality, cardiovascular mortality, and major vascular complications. Clinical outcomes were similar between patients with mildly reduced and preserved LVEF. In conclusion, when performed in women with reduced LVEF, TAVI was associated with a worse (VARC-2) safety profile at 1-year follow-up. In contrast, patients with mildly reduced LVEF appeared to align more closely with outcomes observed in the preserved LVEF group than with the reduced LVEF group.

Mechanical circulatory support for high-risk surgical aortic valve and ascending aortic replacement in severe bicuspid aortic valve stenosis: a case series

Background

Bicuspid aortic valve (BAV) is the most common congenital heart defect (reported incidence of 0.5%-2%) and is commonly associated with proximal aortic dilation. Patients with severe aortic stenosis (AS) of BAV have been shown to have worse pre-operative left ventricular (LV) function as well as a higher incidence of post-operative heart failure hospitalization when compared with analogous patients with tri-leaflet aortic valve disease. While surgical aortic valve replacement (SAVR) may be favoured over transcatheter aortic valve implantation (TAVI) due to anatomical factors or concomitant aortopathy and coronary artery disease, surgical candidacy is often limited by prohibitive operative risk.

Case summary

We report on three cases of severe AS in BAV with concomitant aortopathy and severe left ventricular dysfunction in whom we proceeded with SAVR with a priori planned venoarterial extracorporeal membrane oxygenation (VA-ECMO) support and inotrope-assisted wean. All patients had severe LV dysfunction (ejection fraction < 25%) at baseline with gradual substantial improvement or normalization after successful SAVR.

Discussion

These cases demonstrate the utility of planned VA-ECMO with SAVR and aortic root replacement as an integral component of the operative strategy for high surgical risk patients with severe BAV AS not amenable to TAVI. Appropriate pre-operative planning and consent for VA-ECMO as well as a multi-disciplinary approach involving anaesthesia, intensive care, and heart failure cardiology are the key to offering this option as an alternative to palliative medical therapy to a selected group of patients.

Asymptomatic Aortic Stenosis: From Risk Stratification to Treatment

Our understanding of the natural history of aortic stenosis has significantly increased over the last decade. There have been considerable advances in the diagnosis and risk stratification of patients with aortic stenosis and in surgical and anesthetic techniques. In addition, transcatheter aortic valve replacement has established itself as a viable alternative to surgical management. Inevitably, these developments have raised questions regarding the merits of waiting for symptom onset in asymptomatic patients with severe aortic stenosis before offering treatment. Recent observational and randomized trial data suggest that early intervention in asymptomatic patients with severe aortic stenosis and normal left ventricular function may confer a prognostic advantage to a watchful waiting strategy. In this review, we highlight advances in the management and risk stratification of patients with asymptomatic severe aortic stenosis with particular consideration of recent findings supporting early valvular intervention.

Early Intervention in Asymptomatic Aortic Stenosis: What Are We Waiting For?

Aortic stenosis (AS) contributes to significant cardiovascular morbidity and mortality worldwide, and the natural history from symptoms to ventricular decompensation, heart failure, and death has been well documented. For more than 2 decades, technologies including imaging and biomarkers have shown a promising ability to detect myocardial damage associated with AS before symptoms arise. Current treatment guidelines rely heavily on symptoms or ventricular decompensation as triggers for aortic valve intervention. There is increasing appreciation of the relationship between myocardial damage due to AS before the emergence of symptoms, and a number of published randomised trials suggest a benefit to early intervention in asymptomatic AS, with additional trials actively enrolling. Future treatment paradigms may incorporate early detection of ventricular damage by noninvasive new technologies as triggers for asymptomatic intervention. Enthusiasm for early aortic valve replacement should be tempered by consideration of the competing risks of early valve intervention, but an increasing preponderance of evidence continues to suggest that earlier intervention in AS is warranted.

Asymptomatic Severe and Moderate Aortic Stenosis: Time for Appraisal of Treatment Indications

Over the last decades, we have witnessed considerable improvements in diagnostics and risk stratification of patients with significant aortic stenosis (AS), paralleled by advances in operative and anesthetic techniques. In addition, accumulating evidence points to the potential benefit of early valve replacement in such patients prior to the onset of symptoms. In parallel, interventional randomized trials have proven the benefit of transcatheter aortic valve replacement in comparison to a surgical approach to valve replacement over a broad risk spectrum in symptomatic patients with AS. This article reviews contemporary management approaches and scrutinizes open questions regarding timing and mode of intervention in asymptomatic patients with severe AS. We also discuss the challenges surrounding the management of symptomatic patients with moderate AS as well as emerging dilemmas related to the concept of a life-long treatment strategy for patients with AS.

Aortic Valve Area and Strain Measurements by Cardiac MRI and Transthoracic Echocardiography in Severe Aortic Stenosis with Normal Left Ventricular Function

BACKGROUND

Transthoracic echocardiography (TTE) is the recommended imaging technique for the evaluation of patients with aortic stenosis (AS). However, in cases with inconclusive findings, cardiac magnetic resonance (CMR) planimetry is used to grade AS severity. This study aimed to compare the results derived from TTE and CMR in patients with severe AS with normal left ventricular (LV) function.

METHODS

In a prospective study, 20 patients with severe AS were recruited and data derived from TTE and CMR modalities were compared with the archived records of 28 age- and sex-matched healthy controls. The data included aortic valve area (AVA), MRI-derived biventricular global strains, and TTE-derived global longitudinal strain (GLS). SPSS software was used to analyze the data with independent samples t test, intraclass correlation coefficient (ICC), and Pearson correlation. P<0.05 was considered statistically significant.

RESULTS

An excellent agreement was found in AVA values derived from CMR and TTE with an average ICC of 0.932 (95% CI=0.829-0.973). There was a significant difference in LV-GLS, LV global radial strain (GRS), right ventricular (RV) GRS, and RV global circumferential strain between the groups. A good correlation was found between CMR- and TTE-derived GLS with an average ICC of 0.721 (95% C=0.255-0.896). The mean aortic valve pressure gradient in TTE had a significant inverse linear correlation with LV-GRS in CMR (r=-0.537). All P values were <0.05.

CONCLUSION

There was a good agreement between AVA and strain values derived from cardiac MRI and TTE. The myocardial strain was impaired in patients with severe AS and normal LV function and correlated with disease severity.

Transcatheter Aortic Valve Replacement in Elderly Patients: Opportunities and Challenges

Over the past two decades, the rapid evolution of transcatheter aortic valve replacement (TAVR) has revolutionized the management of severe aortic stenosis (AS) in the elderly. The prevalence of comorbidities in elderly AS patients presents a considerable challenge to the effectiveness and prognosis of patients after TAVR. In this article, we aim to summarize some of the clinical aspects of the current use of TAVR in elderly patients and attempt to highlight the challenges and issues that need further consideration.

Effectiveness and safety of transcatheter aortic valve replacement in elderly people with severe aortic stenosis with different types of heart failure

BACKGROUND

Impaired left ventricular function is an independent predictor of adverse clinical outcomes in patients with aortic stenosis. The aim of this study is to evaluate the short-term changes of echocardiographic parameters, New York Heart Association (NYHA) class and B-type natriuretic peptide (BNP) level and adverse events amongst patients with heart failure (HF) after transcatheter aortic valve replacement (TAVR) procedure.

METHODS

This was a retrospective cohort study conducted at affiliated Yantai Yuhuangding Hospital of Qingdao University between September 2017 and September 2022. TAVR cases were stratified into three groups [heart failure with reduced ejection fraction (HFrEF), heart failure with mildly reduced ejection fraction (HFmrEF), heart failure with preserved ejection fraction (HFpEF)] by left ventricular ejection fraction (LVEF). Baseline characteristics, changes in echocardiographic parameters (1 week and 1 month), BNP (1 month), and NYHA class (6 months) post-TAVR were compared across the three groups. Meanwhile, we observed the adverse events of the patients after TAVR.

RESULTS

A total of 96 patients were included, of whom 15 (15.6%) had HFrEF, 15 (15.6%) had HFmrEF, and 66 (68.8%) had HFpEF. Compared to the HFpEF subgroup, patients in the HFrEF subgroup were younger (p < 0.05), and with a higher BNP (p < 0.05). The left ventricular end-diastolic dimension (LVEDD) in HFrEF group decreased significantly after TAVR. HFmrEF and HFrEF patients showed significant improvements in LVEF after TAVR. The pulmonary artery systolic pressure (PASP), aortic valve peak gradient (AVPG) and aortic valve peak gradient (Vmax) decreased significantly 1 month after TAVR in all three groups compared to the baseline (all p < 0.05). BNP significantly reduced in HFrEF group compared to HFpEF patients after TAVR (p < 0.05). The majority of patients experienced an improvement at least one NYHA class in all three groups 6 months post-TAVR. There is no significant increase in the risk of adverse events in the HFrEF group.

CONCLUSIONS

Patients who underwent TAVR achieved significant improvements in BNP, NYHA class, LVEDD, LVEF, and PASP across the three HF classes, with a more rapid and pronounced improvement in the HFrEF and HFmrEF groups. Complication rates were low in the different HF groups. There is no significant increase in the risk of periprocedural complications in the HFrEF and HFmrEF groups.

Do all patients with asymptomatic severe aortic stenosis need treatment?

INTRODUCTION

Although guidelines recommend a watchful waiting strategy for patients with asymptomatic severe aortic stenosis, there have been considerable advancements in surgical and anaesthetic techniques along with the success of transcatheter aortic valve replacement (AVR) as a viable alternative to surgical AVR. Inevitably, these developments have raised questions as to whether or not there is still merit in waiting for symptoms to ensue before treatment may offered to these patients.

AREA COVERED

The principal purpose of this paper is to review the data supporting earlier intervention in patients with asymptomatic severe aortic stenosis, and to project the implications these and other ongoing trials will have on indications for AVR in asymptomatic patients in the future.

EXPERT OPINION

The threshold for intervention in certain subgroups of asymptomatic patients with severe AS has already been lowered. The next frontier will inevitably be determining whether all patients with severe AS should undergo AVR irrespective of their symptomatic status.

Surgical vs Transcatheter Aortic Valve Replacement in Patients With a Low Ejection Fraction

Currently, there is no preference for surgical (SAVR) vs transcatheter (TAVR) aortic valve replacement in patients with low ejection fraction (EF). The present study retrospectively compared the outcomes of SAVR vs TAVR in patients with EF ≤40% (70 SAVR and 117 TAVR patients). Study outcomes were survival and the composite endpoint of stroke, aortic valve reintervention, and heart failure readmission. The patients who had TAVR were older (median: 75 (25-75th percentiles: 69-81) vs 51 (39-66) years old; P < .001) with higher EuroSCORE II (4.95 (2.99-9.85) vs 2 (1.5-3.25); P < .001). Postoperative renal impairment was more common with SAVR (8 (12.5%) vs 4 (3.42%); P = .03), and they had longer hospital stay [9 (7-15) vs 4 (2-8) days; P < .001). There was no difference between groups in stroke, reintervention, and readmission (Sub-distributional Hazard ratio: .95 (.37-2.45); P = .92). Survival at 1 and 5 years was 95% and 91% with SAVR and 89% and 63% with TAVR. Adjusted survival was comparable between groups. EF improved significantly (β: .28 (.23-.33); P < 0.001) with no difference between groups ( P = .85). In conclusion, TAVR could be as safe as SAVR in patients with low EF.

Clinical, echocardiographic and prognostic outcomes of patients with concordant and discordant high-gradient aortic stenosis in an Asian cohort

Literature of patients with severe high-gradient aortic stenosis (HG AS) (mean pressure gradient [MPG] ≥ 40 mmHg and aortic valve area [AVA] ≥ 1.0 cm2) remains limited. This study seeks to compare the prognostic outcomes of patients with high-gradient concordant (HGCON-AS) and discordant AS (HGDIS-AS) in an Asian cohort. From 2010 to 2015, patients with moderate-to-severe AS with preserved left ventricular ejection fraction (LVEF ≥ 50%) were recruited and stratified into 3 groups based on index echocardiogram-(1) HGDIS-AS, (2) HGCON-AS and (3) moderate AS (MOD-AS). The primary study endpoints was all-cause mortality, with secondary endpoints of congestive heart failure (CHF) admissions and aortic valve replacement (AVR). Multivariable Cox regression was used and Kaplan-Meier curves were constructed to evaluate associations between HGDIS-AS, HGCON-AS and MOD-AS, and the study outcomes. A total of 467 patients were studied, comprising of 6.2% HGDIS-AS, 13.9% HGCON-AS and 79.9% MOD-AS patients. There was significantly higher AVR rates in the HGCON-AS group (58.5%), followed by HGDIS-AS (31.0%) and MOD-AS (4.6%), p < 0.001) groups. After adjusting for confounders, HGCON-AS was significantly associated with all-cause mortality (HR 3.082, 95% CI 1.479-6.420, p = 0.003) and CHF admissions (HR 12.728, 95% CI 2.922-55.440 p = 0.001) but not HGDIS-AS, with MOD-AS as the reference group. Both HGDIS-AS (HR 7.715, 95% CI 2.927-20.338; p < 0.001) and HGCON-AS (HR 21.960, 95% CI 10.833-44.515, p < 0.001) were independent predictors of AVR. After exclusion of reversible high-flow states, HGDIS-AS patients appear to have a more favourable prognostic profile compared to HGCON-AS patients. Large prospective interventional studies examining the prognostic differences between the two groups will be the next important step.

Surgical aortic valve replacement for low-gradient aortic stenosis

AIMS

Low-gradient aortic stenosis is a challenging entity that needs accurate preoperative evaluation. For this high-risk patient population, ad hoc predictive scores are not available and profile risk is currently revealed by the EuroSCOREs. Aims of this study are to verify the suitability of the ES II as predictor of mortality in low-gradient aortic stenosis and to analyse the role of surgery as a treatment.

METHODS

From June 2013 to August 2019, 414 patients underwent surgical aortic valve replacement for low-gradient aortic stenosis. Mean age was 75.78 ± 6.77 years and 190 were women. The prognostic value of Logistic EuroSCORE and EuroSCORE II were compared by receiver-operating characteristics (ROC) curve analysis.

RESULTS

In-hospital, 30-day and 1-year mortality rates were respectively 3.4, 2.9 and 4.8% (14, 12 and 20 patients over 414). In-hospital mortality risk calculated by the Additive EuroSCORE was 7.2 ± 2.7%, by the Logistic EuroSCORE was 9 ± 5.2% and by the ES II was 4.13 ± 2.56%. The prognostic values of the EuroSCORE II and of the EuroSCORE were analysed in a ROC curve analysis for the prediction of in-hospital mortality [area under the curve (AUC): 0.62 vs. 0.58], 30-day mortality (AUC: 0.63 vs. 0.64) and 1-year mortality (AUC: 0.79 vs. 0.65). Both scores did not show significant differences with the only exception of 1-year mortality, for which EuroSCORE II had a better predictive ability than the Logistic EuroSCORE (P < 0.05).

CONCLUSION

In low-gradient aortic stenosis undergoing surgery, the EuroSCORE II is a strong predictor of 1-year mortality.

Clinical outcomes of transcatheter aortic valve replacement stratified by left ventricular ejection fraction: A single centre pilot study

Introduction

To define baseline echocardiographic, electrocardiographic (ECG) and computed tomographic (CT) findings of patients with heart failure undergoing transcatheter aortic valve replacement (TAVR) and analyze their overall procedural outcomes.

Methods

Between 2018 and 2021, patients with severe aortic stenosis (AS) who performed transcatheter aortic valve replacement (TAVR) in Sabah Al Ahmad Cardiac Centre, Al Amiri Hospital were identified. A retrospective review of patients' parameters including pre-, intra-, and post-procedural data was conducted. Patients were grouped in 2 subgroups according to their EF: EF <40% (HFrEF) and EF ≥ 40%. The data included patients’ baseline characteristics, electrocardiographic and echocardiographic details along with pre-procedural CT assessment of aortic valve dimensions. Primary outcomes including post-operative disturbances, pacemaker implantation and in-hospital mortality following TAVR were additionally analyzed.

Results

A total of 61 patients with severe AS underwent TAVR. The mean age was 73.5 ± 9, and 21 (34%) of the patients were males. The mean ejection fraction (EF) was 55.5 ± 9.7%. Of 61 patients, 12 (20%) were identified as heart failure with reduced EF (<40%). These patients were younger, more often males, and were more likely to have coronary artery disease (75% versus 53.1%). Left ventricular hypertrophy and diastolic dysfunction was documented in 75% and 58.3% of patients with heart failure with reduced ejection fraction (HFrEF) respectively. Post TAVR conduction disturbances, with the commonest being LBBB was observed in 41.7%. Permanent pacemaker was implanted in 3 of patients with HFrEF (25%). There were no significant differences between the two groups with regards to in hospital mortality (p = 0.618).

Conclusion

Severe AS with EF <40% constitute a remarkable proportion of patients undergoing TAVR. Preliminary results of post-operative conduction disturbances and in hospital mortality in HFrEF patients were concluded to not differ from patients with LVEF ≥40%.

•

This is the first reported outcome study of TAVR in patients with heart failure in Kuwait.

•

Conduction disturbances induced by TAVR was observed in almost half of the patients.

•

Systolic dysfunction was not a predictor of in hospital complications or mortality outcomes.

Perceval S, sutureless aortic valve: cost-consequence analysis

INTRODUCTION

Sutureless aortic valve prostheses have the potential of shortening ischemic time.

AIM

We conducted the present study to assess the clinical and economic impact of the biological, sutureless, self-expanding Perceval S valve since the effect of shortened operative times on hospital costs remains unclear.

MATERIAL AND METHODS

This is a retrospective analysis. From January 2018 to January 2019, 29 patients underwent isolated aortic valve replacement with the Crown PRT bioprosthetic Aortic Valve, whereas 35 patients underwent aortic valve replacement with Perceval S (auto-expanded, sutureless, bioprosthesis). Preoperative data, hospital outcome, and health care resource consumption were compared, using χ2 and t-test.

RESULTS

Aortic cross-clamp, cardiopulmonary bypass, and operation times were significantly shorter in the Perceval S group (p < 0.001). Patients in the sutureless group required blood transfusion less frequently (p = 0.03) and had a shorter intensive care unit (ICU) stay (p = 0.01). Hospital stay (p = 0.57) and pacemaker implantation were similar between groups. The reduction of aortic cross-clamp, extracorporeal circulation times, and ICU stay resulted in reduced resource consumption in the sutureless group.

CONCLUSIONS

The use of the Perceval S valve is clinically safe and effective. A shorter procedural time in the sutureless group is associated with better clinical outcomes and reduced hospital costs.

Clinical and Echocardiographic Results of Aortic Valve Replacement in the Failing Ventricle: Do Aortic Stenosis and Aortic Regurgitation Differ?

BACKGROUND

We hypothesized that long-term clinical and echocardiographic recovery of the impaired ventricle from pressure (aortic stenosis [AS]) and volume (aortic regurgitation [AR]) overload would be different after aortic valve replacement (AVR).

METHODS

We compared the results of AVR in patients with a preoperative ejection fraction (EF) of 0.35 or less due to AS, AR, or mixed disease. We constructed a mixed-effects model of EF and left ventricular (LV) end-diastolic diameter (LVEDD) to understand ventricular recovery over the short- (in-hospital), intermediate- (3-6 months), and longer- (>24 months) terms. We sought to identify factors associated with clinical and echocardiographic recovery using multivariable analysis.

RESULTS

Between July 2011 and 2017, 136 patients with a preoperative EF of 0.35 or less and severe AS (n = 83), severe AR (n = 18), or mixed AS and AR (n = 35) underwent AVR. There were 2 (1.5%) early deaths in the AS group. Survival at 1, 2, and 5 years did not differ between groups. Baseline EF did not differ between the groups but improved with markedly different trajectory and time course in the AS, AR, and mixed groups over time. LVEDD regressed in all patient cohorts, following a different pattern for AS and AR. Baseline EF and LVEDD predicted the long-term fate of the LV but did not determine survival. We identify factors associated with long-term survival.

CONCLUSIONS

The pattern of LV recovery appears to be early in AS and delayed in AR. Baseline clinical factors, rather than echocardiographic status of the LV, appear to determine late survival.

Timing of aortic valve replacement in high-gradient severe aortic stenosis: impact of left ventricular ejection fraction

BACKGROUND

Patients with high-gradient (HG) severe aortic stenosis (AS) and left ventricular (LV) dysfunction are at high risk of death. The optimal timing for aortic valve replacement (AVR) is not defined by guidelines. The objective was to define the optimal timing to perform isolated AVR in patients with HG-AS and severe LV dysfunction.

METHODS

We retrospectively included 233 consecutive patients admitted for severe HG-AS (aortic valve area <1cm² and mean gradient ≥40mmHg). Severe LV dysfunction was defined by LV ejection fraction ≤35% (LVEF). All-cause mortality while waiting for AVR and after the intervention (30 days) was compared in patients with (n = 28) and without (n = 205) LVEF ≤35%.

RESULTS

Patients with HG-AS and severe LV dysfunction had a higher risk profile than those with LVEF >35%. AVR was performed in 93% (218/233) of patients, 41% by surgery (SAVR) and 53% by transcatheter (TAVR). TAVR was the preferred method to treat HG-AS patients with LVEF ≤35%. All-cause mortality while waiting for AVR was higher in patients with severe LV dysfunction (22% vs. 2.0%, p < 0.001) and occurred within a shorter time (12 [8-26] days vs. 63 [58-152] days, p = 0.010) compared to those with LVEF >35%. All death in HG-AS patients with a severe LV dysfunction occurred within the first month. Postoperative mortality was low (1.3%), irrespective of LVEF.

CONCLUSIONS

AVR should be performed promptly after Heart Team decision in patients with HG severe AS and LVEF ≤35% because of a very high and premature risk of death while waiting for intervention.

Valvular Disease and Heart Failure with Preserved Ejection Fraction

Heart failure with preserved ejection fraction (HFpEF) is a clinical syndrome of shortness of breath and/or exercise intolerance secondary to elevated left ventricular filling pressures at rest or with exertion either as a result of primary diastolic dysfunction (primary HFpEF) or secondary to specific underlying causes (secondary HFpEF). In secondary HFpEF, early intervention of underlying valvular heart disease generally improves symptoms and prolongs survival. In primary HFpEF, there is increasing awareness of the existence and prognostic implications of secondary atrioventricular valve regurgitation. Further studies will clarify their mechanisms and the effectiveness of valvular intervention in this intriguing HFpEF subgroup.

Impact of Surgical and Transcatheter Aortic Valve Replacement in Low-Gradient Aortic Stenosis: A Meta-Analysis

OBJECTIVES

The aim of this study was to assess the impact of aortic valve replacement (AVR) on survival in patients with each subclass of low-gradient (LG) aortic stenosis (AS) and to compare outcomes following surgical AVR (SAVR) and transcatheter AVR (TAVR).

BACKGROUND

LG severe AS encompasses a wide variety of pathophysiology, including classical low-flow, LG (LF-LG), paradoxical LF-LG, and normal-flow, LG (NF-LG) AS, and uncertainty exists regarding the impact of AVR on each subclass of LG AS.

METHODS

PubMed and Embase were queried through October 2020 to identify studies comparing survival with different management strategies (SAVR, TAVR, and conservative) in patients with LG AS. Pairwise meta-analysis comparing AVR versus conservative management and network meta-analysis comparing SAVR versus TAVR versus conservative management were performed.

RESULTS

Thirty-two studies with a total of 6,515 patients and a median follow-up time of 24.2 months (interquartile range: 36.5 months) were included. AVR was associated with a significant decrease in all-cause mortality in classical LF-LG (hazard ratio [HR]: 0.42; 95% confidence interval [CI]: 0.36 to 0.48), paradoxical LF-LG (HR: 0.41; 95% CI: 0.29 to 0.57), and NF-LG (HR: 0.41; 95% CI: 0.27 to 0.62) AS compared with conservative management. SAVR and TAVR were each associated with a decrease in all-cause mortality in classical LF-LG (HR: 0.46 [95% CI: 0.38 to 0.55] and 0.49 [95% CI: 0.37 to 0.64], respectively), paradoxical LF-LG (HR: 0.42 [95% CI: 0.28 to 0.65] and 0.42 [95% CI: 0.25 to 0.72], respectively), and NF-LG (HR: 0.40 [95% CI: 0.21 to 0.77] and 0.46 [95% CI: 0.26 to 0.84], respectively) AS compared with conservative management. No significant difference was observed between SAVR and TAVR.

CONCLUSIONS

In all subclasses of LG AS, AVR was associated with a significant decrease in all-cause mortality regardless of surgical or transcatheter approach.

Speckle tracking echocardiography in severe patient-prosthesis mismatch

BACKGROUND

Although aortic valve replacement (AVR) when successfully performed boasts low mortality rates in selected patients, prosthesis-patient mismatch (PPM) can be found in the majority of these individuals. Limited research is available supporting the benefit of two-dimensional speckle tracking echocardiography (2D-STE) in patients with severe PPM. This study sought to assess myocardial strain using 2D-STE to determine the relationship between subclinical left ventricular (LV) dysfunction and aortic PPM in patients undergoing AVR with preserved LV ejection fraction.

MATERIAL AND METHODS

We retrospectively examined all consecutive patients with isolated AVR who presented to our center from 2005 to 2018. The data of 1086 patients were analyzed. Severe PPM was defined as an indexed effective orifice area of 0.65 cm²/m² or less. As a result of the detailed assessment, 54 patients meeting the eligibility criteria were included in the study. Baseline data were collected and compared between the two groups of patients with severe PPM (n = 27) and those with normofunctional aortic prosthesis valve as a control group (n = 27). All patients underwent baseline echocardiography. Global longitudinal strain (GLS) and global circumferential strain (GCS) were evaluated by 2D-STE.

RESULTS

When compared with controls, patients with severe PPM had significantly decreased GLS (18.6 ± 2.9 vs. 21.4 ± 2.1; p < 0.01) and GCS (17.2 ± 3.6 vs. 21.7 ± 2.1; p < 0.01) values.

CONCLUSION

In addition to standard clinical and echocardiographic parameters, GLS and GCS suggest subclinical dysfunction and have incremental value in patients with severe PPM.

Patient survival in severe low-flow, low-gradient aortic stenosis after aortic valve replacement or conservative management

BACKGROUND AND AIM

Classical and paradoxical low-flow, low-gradient (LFLG) aortic stenosis (AS) are the most challenging subtypes of AS. The current therapeutic options are aortic valve replacement (AVR) and conservative management: AVR promotes long-term survival but is invasive, while conservative management yields a poor prognosis but is noninvasive since it uses no aortic valve replacement (noAVR). The present meta-analysis investigated the rate of survival of patients with LFLG AS undergoing either AVR or noAVR interventions.

METHODS

The meta-analysis compared the outcomes of AVR with those of noAVR in terms of patient survival. In both groups, a meta-regression was conducted to investigate the impact on patient survival of the left ventricular ejection fraction (LVEF), either preserved (paradoxical LFLG AS) or reduced (classical LFLG AS).

RESULTS

The relative risk of survival between the AVR and noAVR groups was 1.99 [1.40, 2.82] (p = .0001), suggesting that survival tends to be better in AVR patients than in noAVR patients. The meta-regression revealed that a reduced LVEF may be related to a higher survival in AVR patients when compared to a preserved LVEF (p = .04). Finally, the analysis indicated that LVEF seems not to be prognostic of survival in noAVR patients (p = .18).

CONCLUSIONS

Patients with LFLG AS have better survival if they undergo AVR. In AVR patients, reduced LVEF rather than preserved LVEF is related to better survival, whereas there seems to be no difference in prognostic value between reduced and preserved LVEF in noAVR patients.

Aortic pulse wave velocity and its relationship with transaortic flow and gradients in patients with severe aortic stenosis undergoing aortic valve replacement

Background

Low-flow, low-gradient severe aortic stenosis (LFLGAS) is a common clinical entity and is associated with poor prognosis. Increased left ventricular (LV) afterload is one of the mechanisms contributing to low LV stroke volume index (SVi) in these patients. Aortic stiffness is an important determinant of LV afterload, but no previous study has evaluated its relationship with LVSVi in patients with AS.

Methods

Fifty-seven patients (mean age 66 ± 8 years, 71.9% men) with severe AS [aortic valve area (AVA) < 1.0 cm²] undergoing aortic valve replacement (AVR) were included in this study. Echocardiographic parameters of AS were correlated with carotid-femoral pulse wave velocity (cfPWV), a measure of aortic stiffness, derived using PeriScope® device.

Results

Mean AVA was 0.63 ± 0.17 cm² with mean and peak transvalvular gradient 56.5 ± 18.8 mmHg and 83.2 ± 25.2 mmHg, respectively. Nearly half (26 of 57, 45.6%) of the subjects had SVi <35 mL/m², indicative of low-flow severe AS. These subjects had lower AVA, lower aortic valve gradient, and LV ejection fraction. CfPWV was numerically lower in these subjects [median 1467 (interquartile range 978, 2259) vs 1588 (1106, 2167)] but the difference was not statistically significant (p = 0.66). However, when analyzed as a continuous variable, cfPWV had significant positive correlation with SVi (Pearson's r 0.268, p = 0.048) and mean aortic valve gradient (Pearson's r 0.274, p = 0.043).

Conclusions

In patients with severe AS undergoing AVR, aortic stiffness measured using cfPWV is not a determinant of low-flow state. Instead, an increasing cfPWV tends to be associated with increasing transvalvular flow and gradient in these patients.

Impact of Left-Ventricular Dysfunction in Patients With High- and Low- Gradient Severe Aortic Stenosis Following Transcatheter Aortic Valve Replacement

BACKGROUND

Outcomes of transcatheter aortic valve replacement (TAVR) in patients with high-gradient (HG) severe aortic stenosis (AS) and reduced left-ventricular (LV) ejection fraction (EF) are unknown.

METHODS

Patients undergoing TAVR for native severe AS between 2009 and 2018 were retrospectively included and classified into 3 groups: HG (≥ 40 mm Hg) and preserved EF (≥ 50%), HG low EF (< 50%), and low gradient (LG < 40 mm Hg) low EF. The primary endpoint was a composite of cardiovascular mortality and readmission for heart failure at 1 year after TAVR.

RESULTS

Of the 526 patients included, 323 (61%) had HG preserved EF, 69 (13%) had HG low EF, and 134 (26%) had LG low EF. HG low EF group had higher prevalence of atrial fibrillation and heart failure and higher Society of Thoracic Surgeons score compared with the HG preserved EF group. Patients in the LG low EF group were older and had higher prevalence of coronary artery disease compared with those in the HG groups. All-cause mortality at 30 days (4.0%) was similar across the 3 groups. After adjustment, the risk of primary endpoint was similar in the HG low-EF vs preserved EF groups. Conversely, the risk of primary endpoint was higher in the LG low EF group vs the HG preserved EF group (hazard ratio [HR], 2.24; 95% confidence interval [CI],1.36-3.70; P = 0.002) and vs HG low EF group (HR, 3.50; 95% CI, 1.55-7.90; P = 0.003), whereas the risk of all-cause mortality was similar across the 3 groups.

CONCLUSIONS

The outcome of patients with HG low EF severe AS following TAVR is as good as that of patients with HG preserved EF.

Minimally Invasive Sutureless Aortic Valve Replacement is Associated With Improved Outcomes in Patients With Left Ventricular Dysfunction

Objective

Patients with severe aortic stenosis and reduced left ventricular ejection fraction (LVEF) have a poor prognosis compared with patients with preserved LVEF. To evaluate the impact of sutureless Perceval (LivaNova, Italy) aortic bioprosthesis on LVEF and clinical outcomes in patients with baseline left ventricular (LV) dysfunction who underwent isolated aortic valve replacement (AVR).

Methods

Between March 2011 and August 2017, 803 patients underwent AVR with Perceval bioprosthesis implantation. Fifty-two isolated AVR had preoperative LVEF ≤45%. Mean age of these patients was 77 ± 6 years, 24 patients were female (46%), and mean EuroSCORE II was 9.4% ± 4.8%. Perceval bioprosthesis was implanted in 9 REDO operations. In 43 patients (83%), AVR was performed in minimally invasive surgery with an upper ministernotomy ( n = 13) or right anterior minithoracotomy ( n = 30).

Results

One patient died in hospital. Cardiopulmonary bypass and aortic cross-clamp times were 85.5 ± 26 minutes and 55.5 ± 19 minutes, respectively. At mean follow-up of 33 ± 20 months (range: 1 to 75 months), survival was 90%, freedom from reoperation was 100%, and mean transvalvular pressure gradient was 11 ± 5 mmHg. LVEF improved from 37% ± 7% preoperatively to 43% ± 8% at discharge ( P < 0.01) and further increased to 47% ± 9% at follow-up ( P = 0.06), LV mass decreased from 149.8 ± 16.9 g/m2 preoperatively to 115.3 ± 11.6 g/m2 at follow-up ( P < 0.001), and moderate paravalvular leakage occurred in 1 patient without hemolysis not requiring any treatment.

Conclusions

AVR with sutureless aortic bioprosthesis implantation in patients with preoperative LV dysfunction demonstrated a significant immediate and early improvement in LVEF.

Meta-Analysis of Outcomes of Transcatheter Aortic Valve Implantation Among Patients With Low Gradient Severe Aortic Stenosis

Transcatheter aortic valve implantation (TAVI) has emerged as an effective therapy for patients with severe aortic stenosis (AS). However, data on TAVI outcomes in patients with low gradient (LG) AS are limited. We performed a meta-analysis of studies comparing TAVI outcomes between patients with classic high gradient (HG) and LG AS through November 2018. The 30-day mortality, mid-term all-cause, and cardiovascular mortality at maximum follow-up were compared between patients with HG and LG AS (Pairwise meta-analysis), and between the three distinct groups of AS including HG, paradoxical low-flow low-gradient and low gradient with reduced ejection fraction (rEF-LG) (Network meta-analysis). Nineteen studies (n = 27,204 patients) met the inclusion criteria. The HG group had less 30-day, mid-term all-cause and cardiovascular mortality compared with the low-gradient AS group overall, (6% vs 7.5%, OR 0.76, 95% CI 0.66 to 0.87, I² = 18%), (21% vs 29%, OR 0.59, 95% CI 0.52 to 0.67, I² = 62%), and (12.6% vs 18.7%, OR 0.61, 95% CI 0.49 to 0.76, I² = 62%), respectively, p <0.0001. These outcomes were confirmed in a trial sequential analysis in which the cumulative Z-curve crossed the conventional test boundary as well as the trial sequential monitoring boundary for all outcomes. The network meta-analysis revealed that patients with rEF-LG had similar outcomes to those with pLFLG, and both had worse outcomes than patients with classic HG AS. In conclusion patients with classic HG have better 30-day mortality, mid-term all-cause and cardiovascular mortality compared with LG patients following TAVI. Among patients with LG severe AS, TAVI outcomes were similar in patients with rEF-LG and pLFLG.

Coronary Microcirculation in Aortic Stenosis

Aortic stenosis is a heterogeneous disorder. Variations in the pathological and physiological responses to pressure overload are incompletely understood and generate a range of flow and pressure gradient patterns, which ultimately cause varying microvascular effects. The impact of cardiac-coronary coupling depends on these pressure and flow effects. In this article, we explore important concepts concerning cardiac physiology and the coronary microcirculation in aortic stenosis and their impact on myocardial remodeling, aortic valve flow patterns, and clinical progression.

Effect of Baseline Left Ventricular Ejection Fraction on 2-Year Outcomes After Transcatheter Aortic Valve Replacement

Background:

Impaired left ventricular function is associated with worse prognosis among patients with aortic stenosis treated medically or with surgical aortic valve replacement. It is unclear whether reduced left ventricular ejection fraction (LVEF) is an independent predictor of adverse outcomes after transcatheter aortic valve replacement.

Methods and Results:

Patients who underwent transcatheter aortic valve replacement in the PARTNER 2 trials (Placement of Aortic Transcatheter Valves) and registries were stratified according to presence of reduced LVEF (<50%) at baseline, and 2-year risk of cardiovascular mortality was compared using Kaplan–Meier methods and multivariable Cox proportional hazards regression. Of 2991 patients, 839 (28%) had reduced LVEF. These patients were younger, more often males, and were more likely to have comorbidities, such as coronary disease, diabetes mellitus, and renal insufficiency. Compared with patients with normal LVEF, patients with low LVEF had higher crude rates of 2-year cardiovascular mortality (19.8% versus 12.0%, P <0.0001) and all-cause mortality (27.4% versus 19.2%, P <0.0001). Mean aortic valve gradient was not associated with clinical outcomes other than heart failure hospitalizations (hazard ratio [HR], 0.99; CI, 0.99–1.00; P =0.03). After multivariable adjustment, patients with reduced versus normal LVEF had significantly higher adjusted risk of cardiovascular death (adjusted HR, 1.42, 95% CI, 1.11–1.81; P =0.005), but not all-cause death (adjusted HR, 1.20; 95% CI, 0.99–1.47; P =0.07). When LVEF was treated as continuous variable, it was associated with increased 2-year risk of both cardiovascular mortality (adjusted HR per 10% decrease in LVEF, 1.16; 95% CI, 1.07–1.27; P =0.0006) and all-cause mortality (adjusted HR, 1.09; 95% CI, 1.01–1.16; P =0.02).

Conclusions:

In this patient-level pooled analysis of PARTNER 2 patients who underwent transcatheter aortic valve replacement, baseline LVEF was an independent predictor of 2-year cardiovascular mortality.

Clinical Trial Registration:

URL: https://www.clinicaltrials.gov . Unique identifiers: NCT01314313, NCT02184442, NCT03222128, and NCT02184441.

Self-Expanding Transcatheter Aortic Valve Replacement in Patients With Low-Gradient Aortic Stenosis

OBJECTIVES

The authors sought to compare clinical and hemodynamic outcomes in patients receiving transcatheter aortic valve replacement (TAVR) for low-gradient (LG) aortic stenosis in the CoreValve EUS (Expanded Use Study) versus those with high-gradient (HG) aortic stenosis from the CoreValve U.S. Pivotal Extreme Risk Trial and CAS (Continued Access Study).

BACKGROUND

The EUS examined the impact of TAVR in patients unsuitable for surgical aortic valve replacement who were excluded from the U.S. Pivotal Extreme Risk Trial due to LG aortic stenosis.

METHODS

EUS patients were stratified by left ventricular ejection fraction: normal (≥50%, LG-normal ejection fraction), and low (<50%, did not respond to dobutamine by generating a mean gradient >40 mm Hg and/or velocity >4.0 m/s, "nonresponders"), and compared with extreme-risk patients from U.S. Pivotal and CAS that had either low resting gradient and responded to dobutamine ("responders"), or a high resting gradient (HG) or velocity. The primary endpoint was all-cause mortality or major stroke at 1 year. Hemodynamics and quality of life are reported at 30 days and 1 year.

RESULTS

At 30 days, patients with LG/low left ventricular ejection fraction (nonresponders and responders) had significantly higher rates of all-cause mortality or major stroke, all-cause mortality, and cardiovascular mortality than both HG and LG-normal ejection fraction patients. At 1 year, only the responders had higher rates of these outcomes in comparison to the other 3 groups. Mean gradient and effective orifice area improved significantly in all patients and were maintained through 1 year. New York Heart Association functional classification and Kansas City Cardiomyopathy Questionnaire overall summary scores improved (p < 0.05) in all cohorts through 1 year. When all 4 subgroups were pooled, both decreasing mean gradient and stroke volume index were associated with increased mortality. Pre-procedural mean gradient was the only hemodynamic independent predictor of 1-year mortality by multivariate analysis.

CONCLUSIONS

In this study, TAVR provided EUS patients significant hemodynamic relief with both 1-year survival and quality of life outcomes comparable to Pivotal and CAS patients (Safety & Efficacy Study of the Medtronic CoreValve System-Treatment of Symptomatic Severe Aortic Stenosis With Significant Comorbidities in Extreme Risk Subjects Who Need Aortic Valve Replacement, NCT01675440; Safety and Efficacy Study of the Medtronic CoreValve System in the Treatment of Symptomatic Severe Aortic Stenosis in High Risk and Very High Risk Subjects Who Need Aortic Valve Replacement, NCT01240902; Safety and Efficacy Continued Access Study of the Medtronic CoreValve System in the Treatment of Symptomatic Severe Aortic Stenosis in Very High Risk Subjects and High Risk Subjects Who Need Aortic Valve Replacement, NCT01531374).

Trans-catheter aortic valve replacement program in a community hospital - Comparison with US national data

Symptomatic aortic stenosis remains a surgical disease, with aortic valve replacement resulting in symptom reduction and improvement in survival. For patients who are deemed a higher surgical risk, Transcatheter aortic-valve replacement (TAVR) is a viable, less invasive and increasingly common alternative. The study compares early outcomes in patients treated within one year of the commencement of TAVR program in a community hospital against outcomes of TAVR patients from nationwide reported data (Society of Thoracic Surgeons/ American College of Cardiology TVT registry). Preoperative characteristics and standardized procedural outcomes of all patients who underwent TAVR in Cape Cod Hospital between June 2015 and May 2016 (n = 62, CCH group) were compared using standardized data format to those of TAVR patients operated during the same time period in other centers within the United States participating in the STS/ACC TVT Registry (n = 24,497, USA group). Most preoperative patient characteristics were similar between groups. However, CCH patients were older (age≥80 years: 77.4% versus 64.3%, p = 0.032) and more likely to be non-elective cases (37.1% versus 9.7%, p<0.001). All 62 TAVR procedures in CCH were performed in the catheterization laboratory unlike most (89.7%) of the procedures in the USA group that were performed in hybrid rooms. A larger proportion of patients in the USA registry underwent TAVR under general anesthesia (78.2% vs.37.1%, P<0.001). Early aortic valve re- intervention rate was 0/62 (0%) in the CCH group VS. 74/ 24,497 (0.3%) in the USA group. In hospital mortality, which was defined as death of any cause during thirty days from date of operation, (CCH: 0% vs. USA: 2.5%, p = 0.410) and occurrence of early adverse events (including postoperative para-valvular leaks, conduction defects requiring pacemakers, neurologic and renal complications) were similar in the two groups. The study concludes that with specific team training and co-ordination, and with active support of experienced personnel, high risk patients with severe aortic valve stenosis can be managed safely with a TAVR procedure in a community hospital.

Automated fastener (Core-Knot) versus manually tied knots in patients undergoing aortic valve replacement: Impact on cross-clamp time and short-term echocardiographic results

The Core-Knot device is an automatic fastener used mainly in minimally invasive heart valve surgery procedures, to facilitate knot tying. The purpose of this report is to compare ischemic time and outcomes of surgical aortic valve replacements (SAVRs) utilizing the Core-Knot device compared with manually tied knots.Between January, 2014 and December, 2016, 119 patients underwent SAVR in Cape Cod Hospital. We compared patient's characteristics, cross-clamp time, and outcomes of 75 patients who underwent SAVR using Core-Knot to those of 44 operated using manually tied knots.Patient characteristics were similar between groups. Patients in the Core-Knot group had higher preoperative aortic valve area and higher ejection fraction. The use of Core-Knot was associated with reduced aortic cross-clamp time (median 70 vs 84 minutes; P < .001). Patients undergoing SAVR using Core-Knot were less likely to have postoperative aortic regurgitation (P < .001). Early mortality, and also the rates of early adverse events (including all cardiac, neurologic, and renal complications), and the immediate postprocedure echo findings were similar in the 2 groups. In multivariate analysis, the use of Core-Knot was associated with reduced postoperative mean gradient across the aortic valve and reduced occurrence of postoperative aortic regurgitation. Older age and larger valve size were other predictors of reduced postoperative mean gradients.The use of an automatic fastener (Core-Knot) in surgical aortic valve replacement cases reduce aortic cross-clamp time and help eliminate postoperative paravalvular aortic regurgitation.

Sex-Specific Considerations in Women with Aortic Stenosis and Outcomes After Transcatheter Aortic Valve Replacement

Aortic stenosis (AS) is the most common valvular disease in the elderly and is associated with poor outcomes. Transcatheter aortic valve replacement (TAVR) is an alternative to surgical aortic valve replacement (SAVR) in high-risk patients. Herein, we describe the gender-related differences in baseline characteristics and pathophysiologic response to severe AS, imaging considerations unique to females, and short- and long-term outcomes after TAVR. Women undergoing TAVR are older and frailer, have less cardiovascular comorbidities, smaller femoral artery size, better left ventricular systolic function, hypertrophied and small left ventricles leading to a higher incidence of paradoxical low-flow low-gradient AS, and a greater prevalence of porcelain aorta, smaller aortic annulus size, and lower coronary ostia heights. Imaging and histopathological data also suggests a sex-related myocardial response to pressure overload from AS. Women experience more vascular complications and blood transfusion requirements, serious procedural complications, and a greater incidence of stroke, but have better long-term outcomes than men. Patient-prosthesis mismatch, which is a concern in patients with a small aortic annulus size undergoing SAVR, has not been problematic with TAVR. The aforementioned findings suggest that TAVR may be preferable for women with severe AS. Further studies are warranted to directly compare TAVR with SAVR in women.

Risk of conventional cardiac surgery among patients with severe left ventricular dysfunction in the era of mechanical circulatory support

BACKGROUND

Despite suggestions that severe left ventricle dysfunction may warrant selection of durable mechanical circulatory support over conventional surgery, comparative studies are lacking due to incomplete characterization of patients at highest risk after conventional surgery. We sought to define subsets of patients with severe left ventricle dysfunction who are at greatest mortality risk following conventional cardiac surgery.

METHODS

We studied 892 patients aged ≥ 18 years who underwent conventional coronary or valve surgery from 1993 to 2014, with preoperative ejection fraction ≤ 25%. Exclusions were transcatheter interventions, major concomitant procedures, active endocarditis, and prior/concurrent durable mechanical circulatory support use. Logistic and Cox regression identified determinants of early and late mortality.

RESULTS

Median age was 70 years (interquartile range, 62-76 years), 46% (n = 411) had New York Heart Association (NYHA) functional class IV symptoms, and 16% (n = 142) had undergone prior surgery. Operative mortality was 7.5%. NYHA functional class IV (odds ratio [OR], 1.88; P = .033), prior cardiac surgery (OR, 2.13; P = .017), peripheral vascular disease (OR, 2.55; P = .001), emergency status (OR, 2.68; P = .024), and intra-aortic balloon pump use (OR, 4.95; P < .001) independently predicted operative death. Risk imparted by presence of both NYHA functional class IV symptoms and prior surgery was additive, with a 4-fold increase in early mortality risk (OR, 3.95; P = .003). Prior surgery increased the hazard of late death by 60% (P < .001). In patients without prior surgery, late mortality was greatest in those aged ≥ 70 years (hazard ratio, 1.86; P < .001), especially if NYHA functional class IV symptoms were concurrently present (hazard ratio, 2.25; P < .001). Surgery type (coronary artery bypass graft surgery, aortic valve surgery, or mitral valve surgery) did not predict long-term outcome.

CONCLUSIONS

In patients referred for conventional surgery with an ejection fraction ≤ 25%, prior cardiac surgery, and/or NYHA functional class IV symptoms-particularly in those aged ≥ 70 years-confer significant and sustained survival disadvantages. Such high-risk subsets may benefit from durable mechanical circulatory support consideration.

Management of Patients With Aortic Valve Stenosis

With increased life expectancy and aging of the population, aortic stenosis is now one of the most common valvular heart diseases. Early recognition and management of aortic stenosis are of paramount importance because untreated symptomatic severe disease is universally fatal. The advent of transcather aortic valve replacement technologies provides exciting avenues of care to patients with this disease in whom traditional surgical procedures could not be performed or were associated with high risk. This review for clinicians offers an overview of aortic stenosis and updated information on the current status of various treatment strategies. An electronic literature search of PubMed, MEDLINE, EMBASE, and Scopus was performed from conception July 1, 2016, through November 30, 2017, using the terms aortic stenosis, aortic valve replacement, transcatheter aortic valve replacement (TAVR), transcatheter aortic valve insertion (TAVI), surgical aortic valve replacement, aortic stenosis flow-gradient patterns, low-flow aortic valve stenosis, natural history, stress testing, pathophysiology, bicuspid aortic valve, and congenital aortic valve disease.

The role of echocardiography in transcatheter aortic valve implantation

Transcatheter aortic valve implantation (TAVI) is an effective and less invasive treatment for the increasing population of individuals with severe aortic stenosis (AS). Echocardiography is crucial in the assessment of AS patients from pre- to post-procedure. Transthoracic echocardiography (TTE) may be used to assess patient suitability for TAVI, as well as evaluate the severity of AS, the aortic valve complex, aortic valve morphology, mitral regurgitation (MR), and left ventricular function. Transesophageal echocardiography (TEE) is usually used as an intra-procedural monitoring tool to provide feedback during the procedure, to assess prosthetic valve function, and to detect complications rapidly before and after balloon aortic valvuloplasty (BAV) or transcatheter heart valve (THV) deployment. In this review, the role of echocardiography in the pre-, intra-, and post-TAVI procedure periods is described in detail.

Mechanical Intervention for Aortic Valve Stenosis in Patients With Heart Failure and Reduced Ejection Fraction

The risk and benefit of mechanical interventions in valvular heart disease have been primarily described among patients with normal ejection fraction. The advent of nonsurgical mechanical interventions for aortic stenosis (transcatheter aortic valve replacement) may alter the risk-benefit ratio for patients who would otherwise be at increased risk for valve surgery. This review describes the epidemiology and pathophysiology of aortic stenosis with heart failure and reduced ejection fraction and summarizes the current registry and clinical trial data applicable to this frequently encountered high-risk group. It concludes with discussion of ongoing trials, new approaches, emerging indications, and a potential clinical algorithm incorporating optimal mechanical intervention for patients with aortic stenosis and concomitant reduced ejection fraction.