ST depression, but angiographically clear

In September I had a single, unprecedented, episode of atrial fibrillation. Calcium channel blocker brought me out of it just before I was zapped. Follow up showed fairly severe high blood pressure (eg, 170/90). Now I'm taking Atenolol (50mg) and Ramipril (5 mg), which have moderated the HBP but it is still quite variable and ranges much higher than desirable.

Subsequent stress test was stopped early, at the appearance of depressed ST segments. The cardiologist confirmed that depressed ST segments indicate coronary ischaemia, and he sent me for an angiogram.

The angiogram showed no constriction near or in my beautiful precious heart.

So what now? The atrial fib and the ST depression indicate something not right, but what can it be?

[kenkeith]

EKG ST depression >2  can signify ischemia when associated with a praticular lead, but the abnormal reading requires further testing as the sensitiviy of the test is not very reliable.  Apparently, an occlusion can not be confirmed.  Sometimes the ekg picks up an artifact (harmless, meaningless stray signal).

Atrial fib can be medically treated.  Anticoangulant to prevent blood clotting.