If the blockages are suspected to be borderline certain tests can be done prior to treatment with angioplasty. These tests may include ultrasound of the blocked artery ( IVUS), or other test (FFR),
If the blockages are significant by any of the above measures then intervention treatment with angioplasty and stent is necessary and knowing to reduce risk of heart attack, death, and other serious events. This is based on evidence from research.
Medications are necessary after stent or surgery,but would not get ride of the blockages .
Where are the blockages, i.e. in what arteries?
Did your brother have some sort of objective ischemic evaluation with a stress test done with an imaging modality?
Heart blockages cannot be cleared with medicine and lifestyle alterations alone. However, that does not mean they need to be treated with angioplasty. Is your brother being treated by a board-certified cardiologist who is up to date on the literature regarding this issue. See especially the ORBITA study and the COURAGE study.