Lown's classification: Lown's class I undertook 46.7%, Lown's class II 53.3%, Lown's class III 23.3%, Lown's class IVA 63.3%, Lown's class IVB 36.7%, V 6.7%, p < 0.01.
Phân độ Lown có: Lown I chiếm 46,7%, Lown II chiếm 53,3%, Lown III chiếm 23,3%, Lown IVA chiếm 63,3%, Lown IVB chiếm 36,7%, Lown V chiếm 6,7%, p < 0,01.