A novel 32P deployable balloon system inhibits formation of neointima in porcine coronary arteries after balloon-overstretching injury.
BACKGROUND
Intracoronary radiation has shown the potential to reduce formation of neointima in porcine models of restenosis.


OBJECTIVE
To investigate the feasibility, safety, and efficacy of a new 'deployable-balloon' device with radioisotope 32P integrated into the balloon material.


METHODS
Ten swine were subjected to balloon-overstretching injury in 20 coronary arteries and were randomly allocated to receive a radiation dose of 0, 15, or 20Gy prescribed to 1 mm from the surface of the radioactive balloon material. The animals were killed 4 weeks after the procedure. Their coronaries were perfusion fixed and stained. Vessel parameters (area of intima and length of fracture) and area of thrombus area were analyzed by computer-aided histomorphometry.


RESULTS
Radiation treatment with the new 32P balloon device was performed without complications. The lengts of fracture for the three groups were similar (NS). Formation of neointima after balloon injury was less in members of the radiated groups than it was in controls (area of intima/length of fracture was 0.70 +/-0.12 mm for controls, 0.08+/-0.13mm with 15 Gy, and 0.07+/-0.17 mm with 20 Gy; P < 0.001). Vessels treated with 20 Gy had a greater total area of thrombus (0.00+/-0.00 versus 0.51+/-0.98 mm2, P< 0.01).


CONCLUSIONS
Intracoronary radiation therapy using a new 32P deployable-balloon system is feasible and safe. A radiation dose of 15 Gy was sufficient to inhibit neointimal response in the porcine coronary-balloon-injury model.
Kim
H S
HS
Cardiovascular Research Institute, Washington Hospital Center, DC 20010, USA.
Kollum
M
M
Chan
R C
RC
Trauthen
B
B
Cottin
Y
Y
Bhargava
B
B
Fournadjiev
J
J
Yazdi
H A
HA
Waksman
R
R
D015906:Angioplasty, Balloon, Coronary / Q000295:instrumentation*; D000818:Animals; D001918:Brachytherapy / Q000379:methods; D003327:Coronary Disease / Q000517:prevention & control* / Q000532:radiotherapy; D003331:Coronary Vessels / Q000293:injuries / Q000528:radiation effects*; D005240:Feasibility Studies; D006083:Graft Occlusion, Vascular / Q000517:prevention & control; D010761:Phosphorus Radioisotopes / Q000494:pharmacology*; D011897:Random Allocation; D055502:Secondary Prevention; D013552:Swine; D017539:Tunica Intima / Q000254:growth & development / Q000528:radiation effects
D010761:Phosphorus Radioisotopes