What is the role of septal myectomy in aortic stenosis?

Asymmetric basal septal hypertrophy is present in 10% of patients with hemodynamic significant aortic valve stenosis. From the surgeon's standpoint, it represents a dilemma as it may be implicated in suboptimal short and long-term results after aortic valve replacement (AVR), but also heighten unwarranted complications at the time of surgical correction. To provide insight about the usefulness and safety of concomitant septal myectomy in this setting, we performed a literature review searching Medline from its inception to November 2020 using the Pubmed interface. Only five low evidence retrospective analyses, comprising a total of <200 patients undergoing AVR with concomitant septal myectomy, were found in the literature. In summary, routine myectomy, in the presence of suspected or directly visualized asymmetric septal hypertrophy on echocardiogram during AVR, seems to be a safe procedure, with all authors reporting a low rate or absence of complications. Overall, myectomy in this setting is associated with superior echocardiographic results concerning surrogates of LV remodelling (LVM; LVM index; LVM/height) and diastolic function (E/E'), suggesting some benefit for hemodynamic outcomes. However, to what extent hemodynamic improvement is exclusively attributable to myectomy is uncertain, as is, the clinical significance of such an improvement, with similar short and mid-term survival rates being reported.