Adderall and Alcohol

Im on 20mg of adderall xr and I take it at about 12pm when I wake up. I usually take my adderall 5 days a week, and I have never mixed it with alcohol. Would it cause any extreme issues if I drank (not heavily but enough to get me buzzed) 9 hours after taking my meds? Im mainly only worried about heart attacks as some articles online have scared me about that.

note – I drink once a week very heavily on the day I dont take my meds. Will my tolerance for alcohol help me have less side affects?