Hi,Welcome to HCM,Your brother is having multiple lesion in coronary artery
system,blockage is 70 to 90% he should go for surgery, and LAD is type 3 which supplies beyond apex into the posterior inter ventricular group. Portion of the artery in inter ventricular posterior group known as a posterior recurrent inter ventricular artery which may entirely substitute PDA.In such cases angioplasty
is not advisable and good revascularization can be done with coronary Bypass surgery
.Looking to result of angiogram he is rightly advised CABG. Please go for it.I wish him good luck.Take care.