Bicuspid aortic valve (BAV) is among the most common congenital malformations, though its true prevalence in the population is likely underestimated, as it often functions normally and may remain asymptomatic when pathological changes occur, thus being diagnosed incidentally. One of its clinical presentations, which is also the focus of this study, is aortic stenosis (AS). It is noteworthy that there is a strong association between BAV and aneurysmal pathology of the aortic root and ascending aorta. 

When younger patients with BAV present AS, several factors must be considered in determining an appropriate approach. These include choosing a prosthesis that provides durable valve replacement and strategies to address the potential need for future interventions. This article aims to evaluate short- and long-term outcomes of surgical aortic valve replacement (SAVR) in patients under 65 with AS, focusing on bioprosthetic valve durability and reintervention needs. Additionally, it compares the combined approach of AVR and aneurysm repair in patients with BAV to AVR alone. 

All patients under 65 who underwent SAVR for AS were included, excluding those who underwent concomitant treatments (except aneurysm repair and atrial fibrillation ablation) or had mechanical valves or non-elective surgeries. 

Unicentric data from 498 patients under 65 years, collected between April 2004 and September 2022, were analyzed. Patient follow-up included clinical and echocardiographic data, with a mean echocardiographic follow-up of 5.0 years (range: 2.0–9.6 years), during which patients received an average of four echocardiograms. Clinical follow-up averaged 5.0 years (range: 1.8–9.9 years). 

Among BAV anatomic presentations, 83% displayed Sievers type I morphology, predominantly with left-right fusion. Patients undergoing valve replacement with simultaneous aneurysm repair (AR) had a higher likelihood of moderate/severe aortic insufficiency (35%) compared to those who underwent AVR alone (25%; p = 0.02). The mean aortic diameter of patients undergoing AVR compared to those with concurrent aneurysm repair was 3.8 cm and 4.8 cm, respectively (p = 0.001). 

In terms of operative mortality, no significant differences were found between the two cohorts, with an overall operative mortality of 1.0% (0.7% AVR vs. 1.4% AVR + AR; p = 0.77). Similarly, permanent pacemaker implantation prior to hospital discharge was required in 1.8% of patients with isolated AVR vs. 1.4% in those with AVR + AR. However, patients undergoing AR exhibited a higher incidence of post-surgical strokes: 3.2% AVR + AR vs. 1.1% AVR; p = 0.99. 

Patients undergoing isolated AVR had shorter hospital stays compared to those who had both AVR and AR, with a mean of 4 vs. 5 days, respectively (p = 0.001). Only 5% of patients who underwent AVR experienced bioprosthetic valve failure within the first three years post-surgery. 

After an average follow-up of 5 years, only 37 patients required reintervention. At 10 years, overall survival was 90%, with no differences between groups. The cumulative probability of reintervention at 5 years was 0.3%. No mortality trend differences were observed between patients based on age and sex. 

Based on the data, researchers concluded that, given the high prevalence of AS due to BAV in patients under 65, excellent postoperative results, and the minimal reintervention needs presented by both isolated AVR and AVR + AR, surgical intervention with bioprosthetic implantation remains a sound approach for initial treatment of these patients, whether the valve pathology is isolated or associated with concomitant aortic disease. 

COMMENTARY: 

This article advances the discussion on care approaches for valve pathology, specifically AS associated with BAV. The findings reinforce that surgical intervention aligns with recommendations from previous studies for addressing AS in patients with low surgical risk and minimal comorbidities, such as those under 65. 

Another notable aspect is the comparison between patients undergoing isolated AVR and those who had concurrent aortic aneurysm repair, demonstrating comparable outcomes in most variables, including mortality, reintervention needs, and immediate postoperative outcomes. This lack of statistically significant differences supports a more aggressive surgical approach in low-risk patients with aneurysmal disease (repair at 4.5 cm systematically). However, it is also significant that in isolated AVR patients, the onset of aortic pathology did not occur post-correction of valve disease, suggesting a linkage between both pathologies until surgical intervention. Thus, if the aorta shows no significant pathology at the time of surgery, isolated AVR may be safely considered. 

In summary, this article builds upon our understanding of managing this pathology and opens avenues for future research on valvular disease in younger patients and on the clinical heterogeneity of bicuspid aortic valve (BAV). 

REFERENCE: 

Mehta CK, Liu TX, Baldridge AS, Kruse J, Puthumana J, Bonow RO; Long term durability of bioprosthetic aortic valve replacement in young patients with bicuspid aortic stenosis, JTCVS Structural and Endovascular (2024), doi: https://doi.org/10.1016/j.xjse.2024.100004.