Vol:23

TREATMENT OPTIONS FOR PULMONARY HOMOGRAFT CONDUIT DYSFUNCTION AFTER ROSS SWITCH PROCEDURE

MADEEHA SHAHAZADI, WAQAR AHMAD

Bicuspid Aortic Valve is the most common type of aortic valve abnormality. The Ross procedure is an attractive option in the treatment of aortic valve disease in infants, children, and young adults.

1 The Ross procedure has been performed with low mortality in children and adolescents with isolated aortic valve disease.

2 Long-term outcomes after the Ross procedure remain uncertain. Although the pulmonary autograft is capable of growth, the pulmonary homograft placed in the right ventricular outflow tract (RVOT) does not grow; thus, reintervention can be expected in one quarter of these patients.

3 Given the progressive homograft stenosis, careful follow-up of these patients is warranted in the second decade after operation. In this article we will discuss the types of RVOT interventions after Ross Procedure and significance of ballon dilatation in pulmonary homograft conduit dysfunction.


KEYWORDS:
Ross Switch Procedure, Homograft (a graft obtained from an organism of the same species),
RVOT (right ventricular outflow tract), autograft.
PJC 2012; 23: 41-45

Correspondence:
Madeeha Shahazadi, M.B;B.S, PG. Waqar Ahmad MCPS, FCPS(PAK), MRCP(UK), FRCP. Kulsum International Hospital,
2020-Blue Area, Islamabad, Pakistan.
Email: madeeha_kemu@yahoo.com

INTRODUCTION
The autograft procedure was introduced by Donald Ross in 1967.4 The Ross procedure (or pulmonary autograft) is a cardiac surgery operation where a diseased aortic valve is replaced with the person's own pulmonary valve. A
pulmonary homograft (valve taken from a cadaver) is then used to replace the patient's own pulmonary valve. In comparison with mechanical and homograft valves, anticoagulation is not required and the pulmonary autograft is capable of growth.

5 Several studies reported satisfactory mid-term and long-term results of the Ross operation.

6-9 Right ventricle to pulmonary artery conduit obstruction is a common postoperative sequelae, requiring intervention. There are different options like stenting, balloon dilatation and replacement available for RVOT interventions depending upon the underlying cause. Here, we will discuss a case of 22 yr of male who underwent balloon dilatation of pulmonary valve after 14 yrs of Ross Switch procedure.

CASE REPORT
22 year old male, who had congenital bicuspid aortic valve, underwent ROSS SWITCH PROCEDURE 14 years ago at AFIC. He presented with complaint of exertional dysnea associated with chest pain in out patient department. His clinical examination was insignificant except ejection systolic murmur of 4/6 grade at pulmonary area.
Patient was admitted in Kulsum International Hospital for coronary angiography which showed Ross Surgery with Conduit Dysfunction with normal right ventricular function. Valved RV to PA Conduit Replacement was advised.
Ballooning of pulmonary Homograft conduit was done by using 12mm*4cm Cordis Balloon . It reduced the gradient across pulmonary valve to 49 mmHg. Post ballooning echocardiography showed satisfactory result with no complication.


DISCUSSION
The Ross procedure is named after Dr. Donald Ross - a pioneer in cardiac surgery in the UK - who proposed the procedure in 196210 and first performed it in 1967. Here is brief diagrammatic explanation of this procedure.
Advantages of this procedure are freedom from thromboembolism without the need for anticoagulation, valve grows as the patient grows (i.e. children), favourable hemodynamics and no foreign material present in the valve. The Ross
procedure is usually performed on patients younger than ages 40 to 50 who want to avoid taking long-term anticoagulant medications after surgery. Disadvantage is Single valve disease (aortic) treated with a two valve procedure (aortic and pulmonary).

One of the main objections to the Ross procedure is the genesis of pulmonary valve disease in addition to aortic valve disease. Proponents have argued that biological valves implanted in the pulmonary position would be slow to develop dysfunction, and any dysfunction would be well tolerated due to the lower pressures in the right side of the heart. Survival of homografts in the pulmonary position is good (20-year freedom from reoperation of 80%), and

Step 1: Measurement of the aortic and pulmonic valves