To spare or not to spare—that is the question

A 49-year-old patient with no relevant comorbidities comes to the surgeon’s attention because of an aortic root aneurysm associated with mild-to-severe aortic regurgitation (AR). Will he get out of the operating room with his own valve? Should the surgeon perform a valve-sparing root replacement (VSRR) or an aortic root replacement with a Bentall procedure (ARR)? This is a very real scenario and most of the times the decision will depend on the surgeon’s preferences.

VSRR in general has proven its excellent outcomes with very long follow-up times [1] as long as the surgeon performing it is experienced [2]. If the above-mentioned patient has no relevant AR, the benefits of avoiding anticoagulant therapy and/or structural prosthesis degeneration may convince the surgeon to confidently choose VSRR. The decision is much trickier if moderate or severe AR comes into play.

That is what the study by Norton et al. [3] aims at helping with. They performed a propensity-matched comparison of VSRR and ARR in the subpopulation of patients with moderate or severe preoperative AR. Their population included 195 matched pairs who were treated from 2004 to 2021 in elective, urgent or emergent settings at 2 institutions (Emory University School of Medicine, Atlanta, GA, and Columbia University Medical Center, New York, NY) [3]. The mean age was 49 ± 15 years. Despite this, 74% of ARR used a biological prosthesis. Almost half (45%) of the patients in the VSRR group required associated aortic valve repair. The study found no differences in short-term outcomes such as in-hospital mortality and other complications, nor in 10-year survival. The mean follow-up time was 3.2 years. The need for reoperation was equal in both groups, with endocarditis as the main indication (50%) for surgery. Valve repair was not linked to reoperation. However, follow-up echocardiography showed much higher moderate-to-severe AR in the VSRR group (14% vs 2%, P = 0.002).

The study in question [3] was well conducted and engaging as it has real-world applications in guiding the surgeon to the best choice for the patient in a frequently encountered situation.

The authors reported a similar rate of bicuspid aortic valves (31% in the ARR, 28% in the VSRR group), which we know can be safely preserved in VSRR [4]. It would be interesting to know more about the regurgitation mechanisms, the aspect of the cusps, the presence of large fenestrations, the type of valve repair performed and its impact on outcomes, since this can influence the surgical strategy. All patients were studied with preoperative transoesophageal echocardiography, which has a central role in planning the valve-sparing approach.

As expected, the VSRR group showed longer CPB (233 vs 189 min) and cross-clamp times (204 vs 170 min), even though the ARR group showed higher rates of concomitant ascending aorta replacement distal to the sinotubular junction (35% vs 20%) and mitral valve procedures (6% vs 2%) [3]. This should also be considered when choosing between the 2 strategies, as especially older or fragile patients may benefit from shorter operative times.

The debate on whether preoperative AR grade influences outcomes of VSRR is still open. Several authors [5, 6] found no difference in AR recurrence related to the preoperative regurgitation grade at midterm follow-up. Others linked severe regurgitation to increased risk of significant AR at follow-up among patients treated for acute type A aortic dissection [7]. In Norton et al.’s study, incidence of moderate-to-severe AR was higher at follow-up in the VSRR group compared to the ARR group (5 years: 16% vs 4%, 10 years: 27% vs 10%). However, this did not translate in higher rates of reoperation, although we have no information on how aortic insufficiency impacted on the patients’ quality of life.

The take-home message from this study should be that in high-volume centres with the right know-how, VSRR should always be considered an option given its benefits for the patients, even in those with moderate-to-severe AR. One should also keep in mind, though, that this exposes patients to a higher risk of recurrent regurgitation.

What should the surgeon do then, before treating the patient at the beginning of this text? Replace the valve or not? The Hamletic choice should be tailored on the surgeon’s experience and, when possible, it should also take into account the patient’s preference, once they are well-informed on the benefits and risks of both options. Shakespeare would have suggested ‘Though this be madness, yet there is method in ‘t’ [8].

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