Your uncle probably had a heart attack due ischemia (lack of blood flow) caused by a partially blocked vessel(s). Angioplasty is a procedure to implant a stent that opens the blocked vessel(s). There are no specific risks now that the blocked vessel is opened.
Your uncle should be on medciation that reduces the heart's workload by dilating vessels. Did the heart atttack cause any serious heart cell damage, that would be the deciding factor regarding prognosis? Normally, there are variations in blood pressure, but if the low is it may be due to medication. Doctor's want the BP as slow as possible without side effects; that helps the heart heal.
I believe this happens to some people after MI and reopening the artery with stents. When I had my first stent in 2007, my blood pressure had been 140/98 for years. After stenting it took a dramatic dive to 90/60 which is the border line of hypotension. Over the next few weeks, it gradually crept back up to 140/90 and I had to be put on medication to hold it down again. Then after my bypass it went back to 90/60 but crept back up over about 3 months. In sept 09 I had 5 stents, my blood pressure dropped so much I was on oxygen for a few hours and it then settled at 90/60 again. Now I'm back on blood pressure medication to keep it low because it has gone high again. I have no idea why this happens but my cardiologist said he has known it in a number of patients. As long as it doesn't drop below 90/60 he will be fine, but even then there are ways they can raise it. What is his blood pressure now?
The other possible cause is as Kenkeith points out, that the heart tissue could be damaged and it may be affecting the hearts output. If this was the case, they would normally tell the patient. As the muscle cells recover, the heart will pick up its pumping ability and get things back to normal.
QUOTE: "The other possible cause is as Kenkeith points out, that the heart tissue could be damaged and it may be affecting the hearts output. If this was the case, they would normally tell the patient. As the muscle cells recover, the heart will pick up its pumping ability and get things back to normal".
The reason why my doctor wouldn't have said anything is because he really didn't know at the time of an MI. It sometmes takes months to know. My heart attack caused hypokinesis (impaired heart wall movement from echo) and the EF was below 29% with echo and 13% with cath.
A heart attack results in heart wall movement impairment due to damaged heart cells. If this weren't the situation, there is no heart attack. The damaged heart cells from an heart attack (MI) can be stunned, hibernating, or necrotic (dead) Fortunately my damaged cells were stunned or hibernating and a good supply of blood with a stent to the deficit area revitalized the heart cells over a period of time. Now my heart is pumping a normal output of 59% after 6 years.
I can't think of ther hemodynamics that would cause the BP to go low unless it is medication (beta blocker, ACE inhibitor) High blood pressure can be explained if that were problem. I didn't have high blood pressure prior to MI nor after...medication has lowered significantly below normal. The physiological difference of individuals can have different outcomes subsequent to discharge. But low blood pressure is a good sign and usually that is what the doctor wants...said to me the lower the better without symptoms of course.