Outcomes After Aortic Valve Replacement for Asymptomatic Severe Aortic Regurgitation and Normal Ejection Fraction

Transcatheter aortic valve implantation in patients with high-risk symptomatic native aortic regurgitation (ALIGN-AR): a prospective, multicentre, single-arm study

BACKGROUND

Surgery remains the only recommended intervention for patients with native aortic regurgitation. A transcatheter therapy to treat patients at high risk for mortality and complications with surgical aortic valve replacement represents an unmet need. Commercial transcatheter heart valves in pure aortic regurgitation are hampered by unacceptable rates of embolisation and paravalvular regurgitation. The Trilogy transcatheter heart valve (JenaValve Technology, Irvine, CA, USA) provides a treatment option for these patients. We report outcomes with transfemoral transcatheter aortic valve implantation (TAVI) in patients with pure aortic regurgitation using this dedicated transcatheter heart valve.

METHODS

The ALIGN-AR trial is a prospective, multicentre, single-arm study. We recruited symptomatic patients (aged ≥18 years) with moderate-to-severe or severe aortic regurgitation at high risk for mortality and complications after surgical aortic valve replacement at 20 US sites for treatment with the Trilogy transcatheter heart valve. The 30-day composite primary safety endpoint was compared for non-inferiority with a prespecified performance goal of 40·5%. The primary efficacy endpoint was 1-year all-cause mortality compared for non-inferiority with a performance goal of 25%. This trial is registered with ClinicalTrials.gov, NCT04415047, and is ongoing.

FINDINGS

Between June 8, 2018, and Aug 29, 2022, we screened 346 patients. We excluded 166 (48%) patients and enrolled 180 (52%) patients with symptomatic aortic regurgitation deemed high risk by the heart team and independent screening committee assessments. The mean age of the study population was 75·5 years (SD 10·8), and 85 (47%) were female, 95 (53%) were male, and 131 (73%) were White. Technical success was achieved in 171 (95%) patients. At 30 days, four (2%) deaths, two (1%) disabling strokes, and two (1%) non-disabling strokes occurred. Using standard Valve Academic Research Consortium-2 definitions, the primary safety endpoint was achieved, with events occurring in 48 (27% [97·5% CI 19·2-34·0]) patients (pnon-inferiority<0·0001), with new pacemaker implantation in 36 (24%) patients. The primary efficacy endpoint was achieved, with mortality in 14 (7·8% [3·3-12·3]) patients at 1 year (pnon-inferiority<0·0001).

INTERPRETATION

This study shows the safety and effectiveness of treating native aortic regurgitation using a dedicated transcatheter heart valve to treat patients with symptomatic moderate-to-severe or severe aortic regurgitation who are at high risk for mortality or complications after surgical aortic valve replacement. The observed short-term clinical and haemodynamic outcomes are promising as are signs of left ventricular remodelling, but long-term follow-up is necessary.

FUNDING

JenaValve Technology.

Echocardiographic assessment of aortic regurgitation: a narrative review

Aortic regurgitation (AR) is the third most frequently encountered valve lesion and may be caused by abnormalities of the valve cusps or the aorta. Echocardiography is instrumental in the assessment of AR as it enables the delineation of valvular morphology, the mechanism of the lesion and the grading of severity. Severe AR has a major impact on the myocardium and carries a significant risk of morbidity and mortality if left untreated. Established and novel echocardiographic methods, such as global longitudinal strain and three-dimensional echocardiography, allow an estimation of this risk and provide invaluable information for patient management and prognosis. This narrative review summarises the epidemiology of AR, reviews current practices and recommendations with regards to the echocardiographic assessment of AR and outlines novel echocardiographic tools that may prove beneficial in patient assessment and management.

Long-term survival after surgical or transcatheter aortic valve replacement for low or intermediate surgical risk aortic stenosis: Comparison with general population

BACKGROUND

Long-term survival after surgery for severe aortic stenosis (AS) provides important information regarding the choice between surgical (SAVR) and transcatheter (TAVR) aortic valve replacement. This study investigated the long-term survival of AS patients with low or intermediate surgical risk who underwent SAVR or TAVR in our institution versus that of the Japanese general population.

METHODS

From 2009 to 2019, 1276 consecutive patients underwent SAVR or TAVR for severe AS. Among them, we retrospectively investigated those with low (n = 383) or intermediate (n = 137) surgical risk treated with SAVR and those with low (n = 86) or intermediate (n = 333) surgical risk treated with TAVR. Their post-intervention survival was compared with that of an age- and gender-matched Japanese general population.

RESULTS

The overall 5-year survival rate of SAVR for patients with low surgical risk (mean age, 72 ± 9 years) was not significantly different from that of the general population (90 % vs. 89 %, respectively; p = 0.58), whereas that of patients with intermediate surgical risk (77 ± 6 years) was significantly lower than that of the general population (77 % vs. 84 %, respectively; p = 0.03). After TAVR, the 5-year survival of patients with low (78 ± 8 years) or intermediate (83 ± 5 years) surgical risk was significantly lower than that of the general population (low risk, 64 % vs. 81 %, p < 0.01; intermediate risk, 66 % vs. 71 %, respectively, p = 0.01).

CONCLUSIONS

Our study demonstrated that long-term survival after SAVR for AS patients with low surgical risk was as good as that of the age- and gender-matched general population, while the long-term survival after SAVR for intermediate-risk or TAVR for low- or intermediate-risk patients was lower than that of the general population. These findings suggest that SAVR is an appropriate option for AS patients with low surgical risk and good life expectancy, especially in Japan, where the life expectancy is the longest worldwide.

Optimal Management of Chronic Severe Aortic Regurgitation - How to Determine Cutoff Values for Surgical Intervention?

Aortic regurgitation (AR) is a common valvular heart disease, but the optimal timing of surgical intervention remains controversial. In the natural history of chronic severe AR, sudden death is rare, and the annual mortality rate is comparatively low. Considering the hemodynamic features of combined volume and pressure overload and long-term compensation in patients with chronic AR, symptoms related to AR do not frequently occur. Therefore, the progression of left ventricular (LV) dysfunction is a key factor in determining the timing of surgical intervention in patients with severe chronic AR. In addition to symptoms, an ejection fraction <50% and an LV endsystolic diameter (LVESD) >45 mm are appropriate cutoff values for surgical intervention in Japanese patients, whereas LV end-diastolic diameter is not a good indicator. An LVESD index of 25 mm/m²is controversial, because adjusting for body size may cause overcorrection in Japanese patients who have a small body size compared with Westerners. Accumulation of data from the Japanese population is indispensable for establishing guidelines on optimal management of patients with chronic AR.

Optimizing Timing of Valve Intervention in Patients With Asymptomatic Severe Valvular Heart Disease

The management of valvular heart disease has changed dramatically over the past decade with advances in cardiac imaging, the use of novel biomarkers, and the development of transcatheter valve repair and replacement technology. International society guidelines have kept pace to provide recommendations for diagnosis, follow-up, and timing of intervention. The most challenging patient cohort for clinicians are patients with asymptomatic severe disease in whom the optimal timing of intervention can be ill-defined. It is a fine balance between the risks of early intervention on asymptomatic patients and improving patient outcomes by preventing long-term cardiac complications. The key in optimal patient management is gathering the necessary information on patient risk and combining that with the risk, efficacy, and durability of valve interventions to arrive at the appropriate timing for intervention. This group of patients will be the focus of this review as we delve into the natural history, recommended follow-up, and indications for intervention in patients with degenerative aortic and mitral valve disease.