Konno Aortoventriculoplasty Research Articles

Technique for Adaptation of Konno Aortoventriculoplasty in Patient-Prosthesis Mismatch.

The patient-prosthesis mismatch has been reported as an important cause of adverse outcome following aortic valve replacement. The relief of patient-prosthesis mismatch generally requires a reoperation of comprehensive nature, which necessitates an extensive aortic root enlargement. The Konno aortoventriculoplasty represents an efficient treatment option, as this technique provides both extreme root enlargement and relief of the frequently associated subvalvular obstruction. However, the application and conduct of the procedure may somewhat differ from the pediatric Konno procedures. This article describes our surgical technique adaptation in Konno-aortoventriculoplasty for adult patient-prosthesis mismatch cases, highlighting the differing points from the pediatric-Konno.

The Externally-Supported Ross Procedure With Konno Aortoventriculoplasty

The Ross procedure remains the best aortic valve replacement option for children and young adults due to the superior hemodynamics, resistance to infection, durability, and lack of thrombogenicity when compared to bioprostheses and mechanical valve options. In particular, avoiding anticoagulation in this patient population is especially advantageous. Modifications to the technique have been developed to ameliorate the most common problem following the Ross procedure: dilatation of the autograft with development of aortic regurgitation. External support of the autograft with a Dacron tube graft have demonstrated excellent early- and mid-term outcomes. In cases of left ventricular outflow tract obstruction, the externally supported Ross procedure can be combined with a Konno aortoventriculoplasty with a few simple modifications. This paper describes the technique of the externally supported Ross procedure with a Sinus of Valsalva Dacron graft (Gelweave Terumo Cardiovascular Group, Ann Arbor, MI) in patients with aortic stenosis. This paper will specifically address the subset of patients with hypoplastic aortic annuli requiring a Konno aortoventriculoplasty.

A Modified Technique of Konno Aortoventriculoplasty for Redo Aortic Valve Replacement Procedures

This article puts forward a modified technique of Konno aortoventriculoplasty for repeat procedures. After incision of the ventricular septum, this approach involves aortic valve replacement using a mechanical valved conduit, reimplantation of the coronary arteries, and graft replacement of the ascending aorta. This modification allows the removal of the diseased ascending aortic wall caused by a previous patch enlargement or poststenotic dilation.

Konno Aortoventriculoplasty Following Arterial Switch Operation Requires Pulmonary Valve Disruption and Right Ventricular Outflow Tract Reconstruction

In the presence of a small aortic annulus, aortic valve replacement can be challenging. Several annular enlarging techniques have been described to allow placement of an adequately sized prosthesis. In patients who have undergone prior cardiac surgery, particularly for congenital heart defects, standard techniques may require modification. This case describes the challenges of enlarging the aortic annulus after previous arterial switch operation for transposition of the great arteries. Specifically, the Konno aortoventriculoplasty following arterial switch operation requires pulmonary valve disruption and right ventricular outflow tract reconstruction.

Konno Procedure for Prosthetic Aortic Valve Endocarditis: 34-Year Follow-Up

A 34-year follow-up is described after a Konno aortoventriculoplasty to correct a restricted aortic annulus and a recurrent aortic prosthetic valve endocarditis with subannular and interventricular abscesses.

The Mini-Ross–Konno procedure

Combining the Konno aortoventriculoplasty with the Ross procedure is being used increasingly for the management of infants and children with complex left-ventricular outflow tract obstruction (LVOTO) associated with aortic valve disease and/or aortic annular hypoplasia. We have successfully used a modification of the technique, effectively relieving the LVOTO without creating a ventricular septal defect (VSD). This modification we refer to as 'Mini-Ross-Konno' simplified the procedure and provided an optimal and long-lasting relief of the LVOTO.

Konno aortoventriculoplasty in children and adolescents: from prosthetic valves to the ross operation

Background. In children with complex multilevel left ventricular outflow tract obstruction (LVOTO), the Konno aortoventriculoplasty is used to enlarge the aortic root and increase the size of the aortic valve implanted. We present our experience with the evolution of this surgical approach from prosthetic valves to the Ross operation. Methods. Between March 1982 and July 2000, 60 patients (36 males and 24 females) had 72 Konno aortoventriculoplasties (prosthetic valve and Konno group [57 patients; redo, 12] and Ross-Konno group [15 patients]). The patients’ ages ranged from 5 days to 18 years (mean, 8.2 years). The underlying anatomic diagnoses were congenital aortic stenosis and LVOTO in 51 patients, coarctation of the aorta with bicuspid aortic valve in 13, severe aortic insufficiency associated with a ventricular septal defect in 8, interrupted aortic arch in 6, mitral stenosis in 6, atrioventricular septal defect in 5, and endocarditis in 3. There was no statistical difference in age or diagnosis between the two groups. The prosthetic valve group included 42 mechanical valves, 9 homografts, and 6 xenografts. Results. Follow-up ranged from 10 months to 18.5 years (mean, 9.7 years) in the prosthetic valve and Konno group compared with 5 months to 3.7 years (mean, 2.1 years) in the Ross-Konno group ( p < 0.05). There were 10 early deaths and four late deaths in the prosthetic valve and Konno group as compared with one early death and two late deaths in the Ross-Konno group ( p = not significant). Reoperations for LVOTO and aortic valve replacement were significantly higher in the prosthetic valve and Konno group as opposed to the Ross-Konno group (16 vs 0, p < 0.05) mainly because of the biological valve and Konno subgroup. There were no statistical differences in reexploration for bleeding, pacemaker insertion, and reoperations for indications other than LVOTO and aortic valve replacement between the two groups. Conclusions. The Konno aortoventriculoplasty is a good surgical option for complex LVOTO. Patients with a prosthetic valve and Konno carry a high rate of reoperation. Early operative results with the Ross-Konno operation seem promising.

The Konno aortoventriculoplasty for repeat aortic valve replacement.

To evaluate the outcome of aortic root augmentation by the Konno-aortoventriculoplasty technique as part of reoperative aortic valve replacement. Since 1983, 15 patients, 12 males and three females, had repeat aortic valve replacement (AVR) with concomitant Konno aortoventriculoplasty. Age ranged from 1.2 to 18 years (mean 12.5 years). The underlying anatomic diagnoses were valve and subvalvar aortic stenosis in 11, truncal valve insufficiency in one, endocarditis in one, Shone's complex in one and severe aortic insufficiency associated with a ventricular septal defect in one patient. All patients had had previous AVR. The causes for reoperation were prosthetic valve stenosis due to growth in ten and paravalvular leak in one, homograft failure in two, xenograft failure in one, and left ventricular outflow tract obstruction (LVOTO) after mitral valve replacement in one patient. The mean size of explanted prostheses was 19.2 mm (13-23 mm) while the mean size of the implanted prostheses was 24.3 mm (19-27 mm) (P<0.01). Previous aortic root enlargement had been performed in 11 patients in conjunction with AVR. The Manougian technique was used previously in two, Konno aortoventriculoplasty in eight, and both techniques in one patient. The newly implanted aortic valves were a homograft in one patient and mechanical prostheses in 14 patients. There was one operative death (1 of 15 or 6.6%) in a 17.5 year old patient with previous AVR and posterior root enlargement, due to low cardiac output state. Follow-up ranged from 6 months to 17 years (mean 7.2 years). The only late death occurred in an 11.6-year-old patient due to prosthetic valve endocarditis. Two patients had complete heart block and had permanent pacemaker insertion (2 of 15 or 13.3%). One patient had pulmonary valve replacement because of combined stenosis and insufficiency 5 years after operation. All 13-surviving patients are asymptomatic at latest follow up. Konno aortoventriculoplasty with repeat AVR may be safely performed. Excellent results may be achieved despite previous aortic root enlargement. It is a good surgical option for complex LVOTO and may even reduce reoperation in children by allowing placement of a larger prosthesis.

Extended aortic root replacement with aortic allografts or pulmonary autografts in children

Objectives: To evaluate the early results and effectiveness of left ventricular outflow tract enlargement with aortic allograft or pulmonary autograft in children with complex left ventricular outflow tract obstruction. Method: The records of 30 children who underwent aortic root enlargement and replacement with either an aortic allograft (22 patients) or pulmonary autograft (8 patients) between January 1987 and June 1997 were reviewed. The predominant diagnosis was complex left ventricular outflow tract obstruction (n = 19), associated with aortic incompetence in 11 children. Before root enlargement, 27 children underwent surgical valvotomy (14 patients), balloon dilatation (10 patients), or both interventions (3 patients). Mean age at root enlargement was 5.4 ± 3.5 years (range, 2 days–16 years). Most of the children (27 patients) underwent a Konno aortoventriculoplasty. Concomitant septal myectomy was performed in 4 children, mitral valve procedure in 5 children, and endocardial fibroelastosis resection in 1 child. Results: Five children (17%) died in hospital. Four of these were infants less than 2 months old. All had acute aortic incompetence as the result of recent intervention necessitating urgent operation. The fifth child, aged 10 years, died of myocardial failure 2 weeks after the operation. During the follow-up period (mean length, 4.1 ± 2.8 years), sudden death occurred in 1 child 3 months after the operation. Follow-up echocardiograms (obtained for 23 of the surviving 24 children within 3 ± 2.3 years) showed a left ventricular outflow tract gradient reduced from a mean of 65 to 11 mm Hg ( P = .001); Z value increased from a mean of –0.5 to 4.1 ( P < .001), and aortic incompetence was trivial or mild except in 2 children. Conclusion: Urgent aortic root enlargement in decompensating neonates carries higher mortality rates. In older children, the early results of root enlargement and implantation of allograft or autograft are good. (J Thorac Cardiovasc Surg 1999;118:503-9)

Commentary: Reoperations after Konno aortoventriculoplasty

Commentary: Reoperations after Konno aortoventriculoplasty

Aortic Valve Replacement with Concomitant Aortoventriculoplasty in Children and Young Adults: Long-term Follow-up

Sixteen patients (9 male, 7 female) underwent aortic valve replacement (AVR) with a Konno aortoventriculoplasty at the University of Nebraska Medical Center from August, 1976, to May, 1986. There was 1 early death (6%), but no operative deaths have occurred since 1977. There was 1 late death from unknown cause 51 months postoperatively. One patient has been lost to follow-up. Long-term follow-up of 14 patients was 923 months (mean, 66 months; range, 9 to 120 months). Of the 16 patients, 12 (75%) had had previous cardiovascular procedures. A total of thirty-five operations, including the aortoventriculoplasties, were done in the 16 patients. Of the aortic valves inserted, 11 were tissue valves (Carpentier-Edwards, 10; Ionescu-Shiley, 1) and 5 were mechanical valves (St. Jude, 3; Björk-Shiley, 2). Patient age at the time of aortoventriculoplasty ranged from 2 years 3 months to 24 years (median, 11 years 8 months). Size of the aortic annulus ranged from 10 to less than 21 mm (median, 16 mm). Valves inserted ranged from 21 to 29 mm; 13 (81%) of them were 25 mm or larger. In 2 patients, degenerated tissue valves were replaced with mechanical valves after 110 and 33 months. At present, all patients are in New York Heart Association Functional Class I. One female patient married and delivered a normal child approximately five years after AVR with a Carpentier-Edwards valve plus aortoventriculoplasty; she never received anticoagulant medications. We conclude that AVR with a concomitant Konno aortoventriculoplasty can be safely performed in the pediatric and young-adult age groups with satisfactory results for up to ten years.

Aortic atresia and aortico–left ventricular tunnel: Successful surgical management by Konno aortoventriculoplasty in a neonate

A newborn infant with aortic atresia and aortico-left ventricular tunnel was successfully treated by Konno aortoventriculoplasty. A 15 mm Ionescu-Shiley pericardial xenograft was inserted when the patient was 5 days old and it was replaced with a 19 mm St. Jude Medical prosthesis at 2 years of age.

Reoperation for prosthetic valve degeneration after Konno aortoventriculoplasty

Since the introduction of the aortoventriculoplasty procedure by Konno in 1975, 16 patients have undergone aortic root augmentation by this method at the Woodruff Medical Center of Emory University. In four patients bioprosthetic valve degeneration 2 to 5 years after the Konno procedure has necessitated repeat operation and replacement of the prosthetic aortic valve. Modification of the septal patch or repeat right ventriculotomy has not been required. One patient required an additional lateral anulus-enlargement procedure (Manouguian) whereas the other three have demonstrated stability or growth of the aortic anulus. We have not observed recurrent subvalvular stenosis or problems with the right ventricular outflow tract. Repeat operation after aortoventriculoplasty has been relatively simple and has usually involved only the supra-annular aorta.

Aortoventriculoplasty ad modum Konno. Experience with five cases.

We have performed Konno's aortoventriculoplasty in 5 children with congenital valvular aortic stenosis and extreme annular narrowing. There was one hospital death, unrelated to the surgical procedure per se. Bleeding from the stitch holes along the patches immediately after bypass was the sole problem associated with the Konno operation in our 4 surviving patients. Preclotting of the dacron patch or use of calf pericardium did not significantly influence this type of bleeding complication. Konno's aortoventriculoplasty permitted considerable enlargement of the original annular circumference and insertion of a size of prosthesis appropriate for adult life (at least 21 mm tissue diameter) in the 4 survivors. The results were still good 1 to 5 (mean 3) years after surgery. The Konno operation is a safe procedure, which widens the hypoplastic aortic annulus to a possible maximum, relieves most forms of ventricular outflow tract obstruction and maintains the prosthetic valve in anatomic sub-coronary position, so that a left ventricular apical-aortic conduit is not required.