Surgical Relief of Left Ventricular Outflow Tract Obstruction in Adults With Congenital Aortic Stenosis and Associated Aortic Annulus Hypoplasia and/or Subaortic Obstruction

Abstract

In children and adolescents, a Ross/Konno operation is commonly done to both enlarge the aortic root and provide a competent aortic valve with relief of left ventricular outflow tract obstruction (LVOTO). Optimum management is not so straightforward in adults. Between 1995 and 2014, 16 patients of mean age 39.4 years (18-57 years) with hypoplastic aortic annulus (AA) measuring 20mm and less, and mean aortic valve/LVOT gradient of 61mmHg (30-70mmHg) presented for surgery. Eight patients with mean LVOT/AA diameter 19.6mm (18-20mm) underwent an "inclusion-cylinder" type Ross procedure (RP). Eight patients with more severe LVOT/AA obstruction, with mean diameter of 17.4mm (16-19mm) underwent mechanical aortic valve replacement (AVR) with standard Konno-type aortoventriculoplasty. There was zero early and late mortality; with mean follow-up of 11.6 years (3-21 years) in the Ross group and 6 years (2-10 years) in the Konno-AVR group. One patient in the Konno-AVR group had reoperation after 2 years for RVOT obstruction. The postoperative echocardiograms of these patients at last follow-up show residual mean gradient across LVOT/AA of 4.4mmHg (2-6mmHg) after RP, and 11.9mmHg (8-17mmHg) after Konno-AVR. In adults, the "inclusion-cylinder" Ross-procedure is a good alternative for mild to moderate aortic root hypoplasia. However, for cases with severe LVOT obstruction, a Ross-Konno is not possible with the same method of autologous support used in a non-Konno RP, and this could be expected to have an impact on late durability and the need for further intervention, in a group that has already undergone multiple procedures in childhood. Both methods of RP and Konno-AVR lead to excellent early and late results.