Function of Contegra valved grafts after unifocalization

BACKGROUND

Can Contegra grafts withstand high pressure?

METHODS

The function of Contegra grafts implanted after unifocalization of major aortopulmonary collateral arteries (MAPCAs) in 10 patients was evaluated. Median age at repair was 194 days and two conduit sizes were used: 12 mm (n = 8) and 14 mm (n = 2). Echocardiography and heart catheterization findings were reviewed.

RESULTS

Two patients died: one early after repair, one late. Death was not graft related. The median duration of observation for survivors was 31 (range 4 - 42) months. The postoperative right ventricular/left ventricular pressure ratio was greater than 75 % in 9 patients. High pressures persisted in 6 survivors. Seven patients underwent interventional dilatation/stenting of pulmonary arteries on 19 occasions. No obstruction was detected in the conduit. Graft valve regurgitation increased in 5 patients, but never exceeded grade 2 (n = 4). Freedom from reoperation for conduit dysfunction/failure was 100 % at month 42.

CONCLUSION

At mid-term follow-up, the Contegra grafts withstood high pressure without significant dysfunction or aneurysmal dilatation requiring surgery. Contegra appears to be an acceptable alternative to the aortic homograft for use after unifocalization of MAPCAs in infancy.

The fate of small-diameter homografts in the pulmonary position

BACKGROUND

Limited durability is expected for small homograft valves that are used to correct congenital cardiac disease.

METHODS

All 76 homograft valves with an internal annulus diameter ranging from 8 to 13 mm that were implanted from 1987 through 2000 in the pulmonary position were retrospectively analyzed. In each case, homograft size was normalized to the patient's body surface area: z-value. For 93% (14 of 15) of the 8 to 9 mm grafts, z was less than 2. For 56% (5 of 9) of the 10 mm grafts and 98% (51 of 52) of the 11 to 13 mm allografts, z was greater than 2. Survival and freedom from complications were estimated by the Kaplan-Meier method. Homograft failure was defined as homograft replacement or late death; significant dysfunction, as homograft obstruction with an echo-Doppler gradient greater than 50 mm Hg or grade III or IV valvular insufficiency. The log-rank test was used to compare outcomes.

RESULTS

Seven patients died early after operation; three, late. Survival was 86.5% +/- 3.8% at 1 year and remained stable during the succeeding years. Freedom from failure for all homografts was 90.6% +/- 3.7%, 71.8% +/- 6.9%, and 61.8% +/- 9.0% at 1, 5, and 10 years, respectively. Corresponding freedom from significant dysfunction was 87.6% +/- 4.1%, 51.2% +/- 7.4%, and 10.1% +/- 8.3%. The smaller homografts (z less than 2) failed and deteriorated faster (p < 0.0001): only 32.1% +/- 13.0% were still functioning at 24 months. The larger grafts (z at least 2) retained function for the first 4 years, and 73.7% +/- 10.4% had not yet failed at 10 years.

CONCLUSIONS

Smaller (z less than 2) homografts (the great majority of 8 to 9 mm grafts) have to be replaced early, usually within 2 years of implantation. Larger (z at least 2) grafts (nearly all 11 to 13 mm grafts) show remarkable durability and are suitable valved conduits for establishing right ventricle to pulmonary artery continuity in neonates and young infants.

[Heart surgery under cardiopulmonary bypass during the neonatal period remains a high-risk procedure]

Congenital Heart disease with a poor prognosis has to be operated early but with an acceptable surgical risk and a good chance of survival. The aim of this study was to analyse the indications, the operative mortality and medium-term survival of neonates undergoing cardiac surgery under cardiopulmonary bypass from 1991 to 1998. Three hundred and twenty nine operations were programmed in 326 neonates, 18% (329/1805) of all open heart surgical procedures. Anatomical detransposition of the great arteries was the commonest operation (N = 226). Correction was complete (biventricular) in 97% of cases (317/326). Twenty-eight neonates died. The operative mortality was 8.5%, much higher than that of children of 3 months or over (1.5%; p < 0.0001). There were 8 late deaths, all in the first postoperative year. The overall medium-term survival rate was 88.9 +/- 1.7%. It was 100% after correction of truncus arteriosus without interruption of the aortic arch; 94.2 +/- 1.5% after anatomical detransposition; 85.7 +/- 9.4% after commissurotomy of aortic stenosis; 79.2 +/- 8.3% for all the complex forms of interruption of the aortic arch; 75 +/- 9.7% for total anomalous pulmonary venous drainage and 42.9 +/- 18.7% after the Norwood palliative procedure of hypoplastic left heart syndrome. The authors conclude that early cardiac surgery saves the large majority of neonates suffering from complex congenital cardiac disease with poor prognosis. Survival stabilises one year after the operation. Other techniques or treatments are necessary to lower present surgical risk (8.5%) to that of surgery under cardiopulmonary bypass of children over 3 months of age (1.5%).

Early and long-term results for correction of total anomalous pulmonary venous drainage (TAPVD) in neonates and infants

OBJECTIVE

To present our 17-year experience of surgical repair of total anomalous pulmonary venous drainage (TAPVD) in 71 consecutive neonates and infants, with particular emphasis on the role of preoperative pulmonary venous obstruction (PVO), the management of postoperative pulmonary hypertensive crises and the long-term results.

PATIENTS AND METHODS

From July 1977 to May 1994, 36 newborns and 35 infants, aged between 1 and 300 days, had repair TAPVD in our Department. Fifty-four patients had decompensated heart failure, whereas three were moribund. The anomalous drainage was supracardiac in 32 (45%), cardiac in 17 (24%), infracardiac in 17 (24%) and mixed in 5 infants (7%). Major associated cardiac anomalies coexisted in nine cases. Forty-five (63%) exhibited signs of PVO. The repair was performed under moderate hypothermia in 15 and deep hypothermic arrest in 56 patients. In case of postoperative pulmonary hypertensive crises, artificial hyperventilation with high oxygen concentration, sedation and relaxation, inotropic support and afterload reduction with phentolamine were applied selectively. The actual follow-up is based on functional symptomatology and cardiac echo-doppler studies.

RESULTS

Six children (8.5%) died early: four perioperatively, two on the 2nd and 10th postoperative day, respectively. Poor preoperative condition, operation before 1987 and preoperative PVO were the main incremental risk factors for death. No death occurred among the last 38 cases. There were complications in 45 patients, in particular pulmonary hypertensive crises in 27. Two patients died late, after 80 and 118 days, respectively, of progressive intrapulmonary vein fibrosis: the second despite reoperation. The risk of late death approaches zero after 6 months. Among the 63 survivors, 56 (86%) are asymptomatic and without medication, 3 months-17 years after operation. Five have mild symptoms with ordinary physical activity. Two are lost to follow-up.

CONCLUSIONS

Early repair of TAPVD with aggressive management of pulmonary hypertensive crises carries low operative mortality nowadays. Preoperative PVO as a risk factor has been neutralized since 1987. Long-term results are gratifying: no late death after 6 months, no reoperation and functional good results. Progressive pulmonary vein fibrosis remains an unpredictable rare cause of death within the 1st year after surgery.