Related Experiment Videos
Porcine heterograft valve replacement in children
Insights
Hancock porcine heterografts showed a high failure rate in pediatric cardiac valve replacement, necessitating reoperation in 7.1% of cases annually. Due to calcification and dysfunction, these valves are no longer routinely used in children.
Area of Science:
- Cardiovascular Surgery
- Pediatric Cardiology
- Biomaterials Science
Background:
- The Hancock porcine heterograft was used for cardiac valve replacement in pediatric patients between 1973 and 1980.
- Long-term outcomes and durability in this young population were evaluated.
Purpose of the Study:
- To assess the long-term efficacy and durability of Hancock porcine heterografts in pediatric patients.
- To determine the rate of prosthetic valvular dysfunction and the need for reoperation.
Main Methods:
- A retrospective analysis of 44 pediatric patients (46 valves) who underwent cardiac valve replacement with Hancock porcine heterografts.
- Follow-up data collected on valve function, patient survival, and reoperation rates.
Main Results:
- Eight valves (17.4%) in seven patients failed due to severe calcification, stenosis, or leaflet disruption, requiring replacement.
- The calculated valve replacement rate was 7.1% per patient-year.
- Younger patients (mean age 8.0 years) were more likely to experience prosthetic dysfunction compared to older patients (mean age 11.2 years).
Conclusions:
- Hancock porcine heterografts demonstrated significant rates of calcification and dysfunction in pediatric patients, leading to reoperation.
- The study concluded that Hancock porcine heterografts are not ideal for long-term cardiac valve replacement in children.
- The practice has shifted towards using mechanical prostheses for pediatric cardiac valve replacement.
Abstract:
From 1973 to 1980, 49 patients under 18 years of age survived cardiac valve replacement with Hancock porcine heterografts. Complete follow-up has been obtained on 44 patients (90%) in whom 46 valves were placed. There were 30 boys and 14 girls with an age range of 2 to 18 years (mean 10.0 years). Severe prosthetic valvular dysfunction requiring valve replacement occurred in eight valves in seven patients at 15 to 60 months postoperatively (mean 34.1 months), yielding a calculated replacement rate of 7.1% per patient-year. All eight valves demonstrated severe calcification with stenosis, two valves had significant insufficiency secondary to leaflet disruption, and one valve had a large leaflet perforation. Thirty-one patients with valves in place at 7 to 90 months (mean 38.4 months) are alive, but six have clinical evidence of progressive valvular dysfunction. The mean age at the time of the original Hancock valve placement of the group of patients having undergone replacement of a failed prosthesis together with those with clinical evidence of prosthetic dysfunction was 8.0 years, which is significantly less than that of the remaining group of patients with normally functioning valves (mean 11.2 years, p = 0.043). Actuarial curves demonstrate a predicted replacement-free rate of 87.4% +/- 5.9% at 3 years. 82.3% +/- 7.5% at 4 years, and 58.5% +/- 15.7% at 5 years. On the basis of these data and other reports of early failure in the literature, we have discontinued the routine use of Hancock porcine heterografts for cardiac valve replacement in children in favor of mechanical prostheses.