1. Ventricular Septal Defect & Aortic Incompetence Seoul National University Hospital Department of Thoracic & Cardiovascular Surgery

2. VSD & Aortic Incompetence 1. Definition VSD and AI syndrome includes hearts in which aortic incompetence is of congenital origin, although rarely present at birth, due to cusp prolapse or a bicuspid aortic valve. The VSD is either doubly committed subarterial or perimembraneous 2. History Laubry & Pezzi : Initial description in 1921 Garamella, Starr : 1st operation in 1960 Spencer, Trusler : Renewed publication of leaflet reconstruction in 1973 preceded by Frater

3. Morphology of VSD & AI 1. Conoventricular (perimembraneous), juxtaaortic, juxtatricuspid VSD are the most prevalent in Caucasian patients. 2. Less commonly, the VSDs are in RV outlet and are juxtaaortic and a few are juxtaarterial. 3. Among Asians, VSDs in RV outlet and particularly juxtaarterial VSDs are more prevalent. 4. Most commonly the right cusp (60-70%) has prolapsed. The noncoronary cusp prolapses in 10-15% both in 10-20%. Uncommonly no cusp is prolapsing, but aortic valve is bicuspid and incompetent. 5. Variable RVOTO are present in many patients. 6. Sinus of Valsalva adjacent to prolapsed leaflet is enlarged.

4. Clinical Features & Diagnosis 1. The exact prevalence of leaflet prolapse with or without AI in conoventricular VSDs is unknown(5%) 2. Younger patients with mild AI The signs of VSD dominate the clinical picture, but as AI increases, the shunt decreases. Such patients have a to-and-fro murmur. 3. Assessed by noting possible presence of aortic leaflet prolapse at cineangiography, echocardiography

5. Etiology of Valve Prolapse Uncertain but ; 1. Lack of support of the aortic sinus and annulus by infundibular septum 2. Structural defect in the base of the sinus itself 3. Hemodynamic influence during both systole and diastole

6. Aortic Valve Prolapse  Pathogenesis 1. Anatomic factors for normal competence Commissary support from above Leaflet support by diastolic apposition Infundibular support from below (Van Praagh) 2. Intrinsic structural abnormality Progressive discontinuity between aortic valve annulus and the aortic media (Yacoub) 3. Hemodynamic factor Venturi effect during early systole – turbulent flow displace the cusp

7. Natural History of VSD and AI 1. Unknown exact prevalence, but is related in part to the age and rare before 2 years 2. AI does not usually appear until 2-5 years of age. 3. Once incompetence appears, it gradually increases and within 10 years is usually severe. 4. More severe because of additional volume load from the VSD than the isolated lesion. 5. Aneurysm of sinuses of Valsalva may develop as part of the natural history in outlet type VSD.

8. Indications for Operation 1. When a child with VSD first shows any signs of development of prolapse, and the murmur of AI, repair of VSD should be promptly accomplished. 2. Even if prolapse has not occurred, juxtaarterial, and RVoutflow juxaaortic VSD should be closed to prevent prolapse. 3. When AI is above moderate, the operation should be undertaken promptly.

9. Technique of Operation 1. When AI is trivial or absent, the VSD only is repaired 2. When AI is significant, and often when mild, the VSD and aortic valve is repaired. 3. The aortic valve must usually be repaired or replaced in adult when AI is moderate or severe. * Trusler’s method of plication * Frater stitch * Triangular excision & reconstruction

10. Trusler Technique Repair of prolapsed aortic valve cusp

11. Yacoub Technique Repair of aortic valve in syndrome of VSD & aortic valve regurgitation

12. Results of Operation 1. Survival 2. Heart block 3. Relief of aortic incompetence 1) Preoperative severity 2) Conoventricular (perimembraneous) VSD 3) Bicuspid valve 4) Old age 4. Freedom from aortic valve replacement 81% in 20 years