Management of Complex Left Ventricular Outflow Tract Obstruction: A Comparison of Konno and Modified Konno Techniques

Abstract

Management of complex left ventricular outflow tract obstruction (LVOTO) can be achieved with a Konno or Modified Konno procedure to enlarge the LVOT. We hypothesized that patients who undergo a Modified Konno procedure would have a higher rate of LVOT re-intervention compared to the Konno procedure. Patients who underwent a Konno or Modified Konno procedure for LVOTO at a single tertiary care center between 1990 and 2014 were retrospectively reviewed. The primary outcome was LVOT re-intervention post-discharge from index Konno or Modified Konno procedure. Cox regression and Kaplan–Meier estimates were used for time-to-event analysis of LVOT re-interventions, any unplanned re-interventions, and transplant-free survival. The study included 122 patients: 51 (41.8%) in the Konno group and 71 (58.2%) in the Modified Konno group. Median age at surgery was 8.2 (IQR 3–16) years in the Konno group and 3.9 (IQR 1.5–11) years in the Modified Konno group. Multiple left heart lesions were less prevalent in Modified Konno patients. There were 36 (29.5%) patients with LVOT re-interventions: 8 (16%) in the Konno group and 28 (39.4%) in the Modified Konno group ( p = 0.01). Transplant-free survival at five years was 87.2% for the Konno group and 93.5% for the Modified Konno group. A higher rate of LVOT re-intervention was found in the Modified Konno group although the Konno and Modified Konno techniques were applied to different patient populations. This finding suggests that careful preoperative decision-making can direct therapy appropriately and that fundamental diagnosis affects procedure choice. Supplementary Information The online version contains supplementary material available at 10.1007/s00246-020-02522-9.

Konno-Rastan procedure in surgical recurrence of congenital aortic stenosis and hypoplastic aortic annulus

“…Gerber Polo-Gutierrez 1 , Pedro Rojas-Sanchez 1 , Fernando Chavarri-Velarde 1 , Wildor Samir Cubas 2 Various case series have shown that the K-R procedure together with aortic valve replacement provides optimal postoperative results with minimal associated mortality rates (< 1%), low mean gradient (< 10 mm Hg), and remission of NYHA IV-III symptoms to I-II [1,3,5]. Likewise, the safety of this technique has been highlighted with a survival greater than 85% and without deterioration of ventricular function in a 20-year follow-up (LVEF, 58-62%) [1,2,6].…”

“…Aortic stenosis (AS) with hypoplastic aortic annulus (HAA), recurrence after percutaneous treatment, progression to severe heart failure, and its association with significant valve insufficiency make it complex and require timely aortic valve surgery [1][2][3]. The Konno-Rastan (K-R) technique consists of enlarging the aortic ring, and provides an aortic annular area compatible with the current hemodynamic requirement of the patient and its subsequent development [4,5]. It is currently considered the most effective for widening the aortic ring and the left ventricular outflow tract, constituting an enormous surgical challenge for today's pediatric cardiac surgeon.…”

“…A complex recurrent HAA, and AS are conditions constituting a serious surgical problem during valve replacement, due to the need to offer an adequate effective valve area for the patient’s requirement, and that offers a lower rate of restriction during growth [ 3 , 5 ]. The implantation of an aortic valve prosthesis must offer an effective area greater than 0.85 cm 2 /m 2 , and in severe cases of HAA, annular enlargement of more than 50% of its diameter is necessary, to avoid prosthesis-patient disproportion (PPD) [ 6 ].…”

“…The K-R procedure is an effective and attractive treatment for LVOT enlargement, surgically incising the aortic root, the interventricular septum, and the anterior wall of the LVOT [ 5 ]. However, this technique has been associated with various complications such as ventricular dysfunction (18.9%), atrioventricular block (61.4%), and perioperative bleeding (26.3%) [ 3 ].…”