Modified Konno for Recurrent Subaortic Membrane

Subaortic membrane is a notoriously recurrent problem, with rates as high as 25%. Modified Konno is recommended for tunnel-type subaortic stenosis with normal aortic leaflets. The risk factors for recurrence are a high preoperative gradient (>80 mmHg), or closeness of the membrane to the aortic valve leaflets. The addition of myectomy has been recommended to reduce recurrence, but this has been controversial. A 2013 study from the Netherlands showed that adding myectomy does not reduce recurrence, but increases the risk of heart block (1).

The authors propose that there can be a subset of patients with discrete subaortic stenosis and a high risk of recurrence who may benefit from modified Konno. The advantages of modified Konno are that it can be done with little additional bypass time and virtually no risk of injury to the conduction system. In this surgical video, a modified Konno for recurrent discrete subaortic stenosis is shown. The indications for surgery were a gradient of 60 mmHg and onset of mild AR.

References:

1. van der Linde D, et al. Surgical outcome of discrete subaortic stenosis in adults: a multicenter study.Circulation 2013;127(11):1184-91.