HOW I DO IT ? MODIFIED NORWOOD’S OPERATION VICHAI BENJACHOLAMAS, MD. CHULALONGKORN HOSPITAL

HYPOPLASTIC LEFT HEART SYNDROME Mitral valve atresia or stenosis Small left ventricle Aortic valve atresia or stenosis Small ascending aorta Various degree of aortic arch obstruction

HYPOPLASTIC LEFT HEART SYNDROME

HYPOPLASTIC LEFT HEART SYNDROME Perop. Management PGE-1  open PDA Avoid oxygen Correct acidosis Inotrope Diuretic Intubation if neccessary

HYPOPLASTIC LEFT HEART SYNDROME Hybrid procedure VS Modified Norwood’s operation

HYPOPLASTIC LEFT HEART SYNDROME Hybrid procedure PDA stenting Bilateral PA banding +/- balloon atrial septostomy

HYPOPLASTIC LEFT HEART SYNDROME Modified Norwood’s operation Aortic and arch reconstruction with/without homograft Atrial septectomy Shunt to pulmonary artery BT shunt or Sano shunt

HYPOPLASTIC LEFT HEART SYNDROME Timing for Norwood’s operation AGE < = 10 days

MATERIALS AND METHODS August 1996 - November 2008 Modified Norwood’s Operation was performed in 26 neonates

AGE 3 - 75 days ( median 11 days ) MATERIALS AND METHODS AGE 3 - 75 days ( median 11 days )

WEIGHT 2,000 - 4,200 grams ( median 2,850 grams ) MATERIALS AND METHODS WEIGHT 2,000 - 4,200 grams ( median 2,850 grams )

ASCENDING AORTA DIAMETER 2 - 7 mm. ( median 2.5 mm. ) MATERIALS AND METHODS ASCENDING AORTA DIAMETER 2 - 7 mm. ( median 2.5 mm. )

HOW I DO IT ?

SURGICAL TECHNIQUE Operate under cardiopulmonary bypass with profound hypothermia Arterial cannulation - at MPA for first 10 patients - at Goretex graft to right bracheo- cephalic artery for last 16 patients Venous cannulation with single venous at Rt. Atrial appendage

SURGICAL TECHNIQUE Resected PDA tissue and aortic ischmus Arch reconstruction with MPA or homograft Atrial septectomy Rt. Modified Blalock-Taussig shunt

SURGICAL TECHNIQUE Homograft = 22 patients aortic = 3/22 patients Arch reconstruction with native MPA = 4 patients Homograft = 22 patients aortic = 3/22 patients pulmonic = 19/22 patients

SURGICAL TECHNIQUE BT Shunt size selection 3.5 mm. for Body weight <= 3.5 kg. 4.0 mm. for Body weight > 3.5 kg.

SURGICAL TECHNIQUE Median CPB time = 96 min. (51-163 min.) Median DHCA time = 66 min. (51-97 min.) Median CPB+ DHCA time = 159 min. (125-216 min.)

SURGICAL TECHNIQUE BT shunt VS Sano shunt

SURGICAL TECHNIQUE Advantages/disadvantages of the modified Blalock-Taussig shunt Advantages Disadvantages No ventriculotomy Increased diastolic runoff Decreased coronary perfusion Decreased right ventricle function Decreased end organ perfusion Limits right ventricle overload Shunt stenosis/thrombosis Good pulmonary artery growth

SURGICAL TECHNIQUE Advantages/disadvantages of the Sano shunt Improved coronary perfusion Higher diastolic pressure Narrowed pulse pressure Right ventriculotomy Arrhythmias Right ventricle dysfunction Right ventricle aneurysm Tricuspid valve dysfunction Lower pulmonary to systemic ratio Early or progressive hypoxemia Pulsatile pulmonary blood flow Increased volume load on right ventricle Improved end-organ perfusion Inadequate pulmonary artery growth Shunt stenosis/thrombosis

Sano shunt benefit in AA, MA SURGICAL TECHNIQUE Sano shunt benefit in AA, MA

POSTOPERATIVE CARE RULE OF FOURTY (40) - Fi O2 ~ 0.40 - Pa CO 2 ~ 40 mmHg. - Pa O2 ~ 40 mmHg. - Hct. ~ 40 %

78 - 85 % ( average 82 % ) POSTOPERATIVE CARE Oxygen saturation after extubation 78 - 85 % ( average 82 % )

Survival rate = 76.9 % (20/26) RESULTS Hospital mortality was 23.1 % (6/26 ) (within 30 days) DOT 3/6 Survival rate = 76.9 % (20/26)

RESULTS Mortality rate by arch reconstruction technique Autologous tissue mortality rate = 50 % (2/4) survival rate = 50 % (2/4) Homograft patch mortality rate = 18.2 % (4/22) survival rate = 81.8 % (18/22)

LATE RESULTS 26 patients 20 survivors 3 loss F/U 5 BDG 1 wait for FONTAN 4 FONTAN 2 waiting for BDG 5 not suitable for BDG 5 BTS 1 FONTAN 2 F/U 2 LD 5 LD 6 HD

DISCUSSION PRE-OPERATION - Need experienced cardiologist to take care the patient before operation - Not to put ET tube in the patient - Stabilize cardiovascular, no acidosis

DISCUSSION INTRA-OPERATION - Arch reconstruction with homograft seem to be better ( smooth postoperative care, early extubation and no late coarctation, especially pulmonary homograft ) - Select proper shunt size to maintain O2 saturation ~ 75-80 %

DISCUSSION POST-OPERATION - Early catheterization at either 5 or 6 mo. old or progress cyanosis - Change to BCP shunt before out-growth of the BT shunt

SUMMARY The treatment of hypoplastic left heart syndrome need a lot effort. Despite good equipment, it needs very good team include neonatal cardiologist, neonatal cardiac anesthetist, neonatal cardiac surgeon, well- trained scrub nurse, keen perfusionist, and keen ICU nurse.