Is it true that sleep apnea can cause cardiac problems ...stents etc.?

Untreated OSA: Untreated obstructive sleep apnea has an increased risk of cardiovascular and cerebrovascular disease.

Yes: Sleep apnea causes arrhythmias, ( irregular rhythms) cardiomegaly (large heart) and is frequently seen with hypertension (high blood pressure). Your entire body has to work a little harder because you're struggling to breathe and get oxygen throughout the night. Stents or blocked coronary arteries may be a little more of an indirect problem with sleep apnea. Both are seen in diabetes and obesity.

R/O OSA: OSA INCREASES BP and risk of MI/CVA SX: Excess snoring/daytime sleepiness/apneic episodes/ aM headaches. And the Exam obesity/small oral airway/collar size>18. The definitive test is a PSG with split night/CPAP titration. I would request copy of sleep study and get a second opinion if you are not satisfied with the options. You are young CPAP can be difficult to tolerate. ENT FOR UPP EVAL.