Heart complication

I am 56 years old with five stents (two in 2018, three in 2023). I am physically active and non-smoking, but I am now experiencing exertional angina that is worsening. I feel chest pain while walking in winter and now while climbing stairs. I am currently on Metoprolol 25mg, Renoline 500 SR, Isonitirate 20, and Clopitrix 75. I recently had cataract surgery in both eyes. I am seeking a definitive diagnostic plan to check for in-stent restenosis or new blockages.