Modified Ross-Konno procedure in children: subcoronary implantation technique with Konno incision for annular and subannular hypoplasia

The Ross-Konno procedure for congenital aortic stenosis

Left ventricular outflow tract (LVOT) obstruction can result from supravalvular, valvular and/or subvalvular etiologies. Congenital aortic valvular stenosis is frequently associated with aortic annular hypoplasia. Aortoventriculoplasty with pulmonary autograft, "The Ross-Konno" operation, provides more or less a radical solution to multilevel LVOT obstruction by enlarging the aortic annulus and the subvalvular area, thus relieving both valvular and subvalvular obstructions. In addition to this, the procedure carries the major advantage of having a competent autograft in the LVOT. An autograft that has the potential for growth and provides excellent quality of life without the need for anticoagulation. The procedure is most commonly performed as a complete root implantation, harvesting the coronary arteries as buttons, and harvesting the autograft with a muscle skirt to allow a single unit reconstruction of the LVOT. The procedure has been modified over time to minimize the risk of conduction tissue injury and the development of complete heart block by modifying the interventricular septal incision. The Ross-Konno procedure has changed the approach to patients with complex multilevel LVOT obstruction. However, while it can be performed early in life, one should be aware that this procedure is technically demanding and can be associated with a higher surgical risk. Nevertheless, it is considered "the ultimate solution" for those with complex multilevel LVOT obstruction.

Subcoronary Ross/Ross-Konno operation in children and young adults: initial single-centre experience

OBJECTIVES

We sought to evaluate the outcome after modified subcoronary Ross/Ross-Konno operation in children and young adults.

METHODS

Between January 2013 and January 2019, a total of 50 patients with median age of 6.3 years (range 0.02-36.5 years, 58% males), including 10 infants (20%), received modified subcoronary Ross/Ross-Konno operation at our institution. Survival, morbidity, reinterventions, aortic valve function and aortic root dimensions were analysed.

RESULTS

At a median follow-up of 31.2 months (range 14.4-51 months), there were 1 early death and 1 late death, both in the infant group. The overall survival at 5 years after the operation was 95%. Two patients needed aortic valve replacement, 11 and 15 months after their Ross operation. At 5 years, freedoms from reoperation on the autograft and on the right ventricle to pulmonary artery conduit were 94% and 97%, respectively. Freedom from aortic valve regurgitation greater than mild was 97% at 5 years. Median dimensions of the aortic root at all levels remained in normal range at last visit. Forty-four patients (95%) were in New York Heart Association class I with normal left ventricular function.

CONCLUSIONS

The initial experience with the subcoronary Ross/Ross-Konno operation in children and young adults showed excellent outcome. The mortality and morbidity among infants remain significant. The described technique is reproducible and might be advantageous in situations when prosthetic supporting techniques interfere with somatic growth.

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

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.