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The Hancock external valved conduit. A dichotomy between late clinical results and late cardiac catheterization
Insights
The Hancock external valved conduit showed significant gradients in asymptomatic children years after surgery. Regular cardiac catheterization is crucial for monitoring these patients.
Area of Science:
- Cardiology
- Pediatric Cardiac Surgery
- Biomedical Engineering
Background:
- The Hancock external valved conduit was implanted in 18 children between 1974 and 1977.
- 17 patients survived the operation, with 15 being long-term survivors (6-9 years post-op).
Purpose of the Study:
- To evaluate the long-term efficacy and complications of the Hancock external valved conduit in pediatric patients.
- To assess the need for serial cardiac catheterization in these patients.
Main Methods:
- Serial cardiac catheterization studies were performed at 1 and 6 years post-operation.
- Patient follow-up included clinical assessment (New York Heart Association Class) and medication review.
Main Results:
- A gradient of ≥50 mm Hg across the conduit was observed in 2/16 patients at 1 year and 7/15 patients at 6 years.
- Five patients (30% of long-term survivors) required conduit replacement and survived reoperation.
- A significant conduit gradient was found in one-third of essentially asymptomatic long-term survivors.
Conclusions:
- The Hancock external valved conduit can develop severe gradients over time, even in asymptomatic patients.
- Serial cardiac catheterization is essential for monitoring Hancock conduit function and detecting potential complications.
- These findings highlight the importance of vigilant follow-up in pediatric patients with prosthetic cardiac conduits.
Abstract:
The Hancock external valved conduit was inserted in 18 children between 1974 and 1977. Seventeen patients survived operation and 15 are long-term survivors of 6 to 9 years. All patients have been closely followed up by the same pediatric cardiologist and each has undergone serial cardiac catheterization studies, generally performed at 1 and 6 years after operation. All long-term surviving patients have been in either New York Heart Association Class I or II. A few continue to take digoxin or diuretics. Cardiac catheterization demonstrated a gradient of 50 mm Hg or greater across the conduit in two of 16 patients 1 year after operation and in seven of 15 patients 6 years after operation. Five patients (30% of all long-term survivors) have had this conduit replaced and each has survived reoperation. The finding of a severe conduit gradient in one third of all long-term surviving patients is particularly bothersome since these patients were essentially asymptomatic. This study emphasizes the need for serial follow-up cardiac catheterization studies in all patients who receive the Hancock conduit.