TTHealthWatch is a weekly podcast from Texas Tech. In it, Elizabeth Tracey, director of electronic media for Johns Hopkins Medicine, and Rick Lange, MD, president of the Texas Tech University Health Sciences Center in El Paso, look at the top medical stories of the week.
This week’s topics include the value of finding atrial fibrillation in those at risk for stroke, social factors in USPSTF recommendations, giving a flu shot to those who’ve had an MI, and treating carotid stenosis.
0:54 Stroke prevention via treating carotid stenosis
1:48 All had good medical therapy afterward
2:50 Avoid atherosclerosis in carotids
3:32 Flu vaccine after MI
4:30 All cause death lower in flu vaccine group
5:31 Reduces future heart attacks
6:32 Discern the mechanism?
8:00 Implantable loop recorder identified
9:00 Those with high blood pressure
9:15 USPSTF on social factors impacting health
10:15 Came down to five questions to examine
11:20 Very start of the social risk factors path
Elizabeth Tracey: Should you get a flu vaccine if you’ve had a heart attack?
Rick Lange, MD: Comparing stenting with surgery for people who have blockage in their carotid artery.
Elizabeth: What is the impact of social factors relative to health in the USPSTF statements?
Rick: Does continuously screening for irregular heart rhythms help prevent stroke?
Elizabeth: That’s what we’re talking about this week on TT HealthWatch, your weekly look at the medical headlines from Texas Tech University Health Sciences Centre in El Paso. I’m Elizabeth Tracey, a Baltimore-based medical journalist.
Rick: I’m Rick Lange, president of Texas Tech University Health Sciences Centre in El Paso where I’m also dean of the Paul L. Foster School of Medicine.
Elizabeth: Rick, let’s mention that we’ve chosen these heart ones because, of course, the European cardiology meeting has just concluded, so we have gotten some really interesting material out of that. You chose two of these studies. I’m going to let you start with the one you like best.
Rick: They are both good, but let’s start with the one that looks at stroke prevention. We know that people who have never had a stroke before, but have a severe blockage in their carotid artery, that’s the artery that supplies blood to the head — now when I say severe, a 75% to 99% blockage — we know that that increases their risk of having stroke. Previous studies have shown that if you have surgery, that’s called a carotid endarterectomy, where they go in and actually peel that blockage out of the artery, you can help prevent strokes in those individuals.
But we have another technique called stenting that actually props the blood vessel open. Are these two equivalent? There have been previous studies that have looked at this, but this is actually a large, very well done study in over 3,600 patients in 130 different centers around the world. They were randomized to either having stenting or carotid surgery. They were asymptomatic, but they have a severe blockage.
All these people had good follow-up and they also had good medical therapy afterwards. They were followed for a mean of five years. Overall, 1% of individuals with either procedure had a disabling stroke or death related to the procedure — 2% had what was called a non-disabling stroke related to the procedure. Serious complications were uncommon after either procedure, they were similar after either procedure, and the long-term results of these carotid artery procedures appear to be comparable.
Elizabeth: Let’s just remind folks that these are in The Lancet. What it sounds like to me is that probably if you get the opportunity to choose, which maybe you can and maybe you can’t, that the thing to do might be to choose a center or choose the procedure where that’s what they do all the time since we know from other procedures that that’s a good idea.
Rick: You’re right. In many of these places, by the way, they were equally talented at doing either of these procedures.
Elizabeth: Clearly, avoiding this outcome of disabling stroke is a good idea. Talk to me a little bit about prevention. What about trying to avoid atherosclerosis in their carotid arteries at the get-go?
Rick: Well, a great question Elizabeth and we talked about good medical therapy. That’s primary prevention, preventing someone from having a stroke, and making sure that someone’s blood pressure is well controlled because that contributes to blockage in the artery, their diabetes is controlled, their smoking cessation, people on a statin medication to lower cholesterol, and oftentimes on an antiplatelet agent like aspirin.
Elizabeth: Finally, let’s just note that this is something that’s routinely screened for with really very-low tech. “Hey, let’s put the stethoscope on your neck and see what we hear.”
Rick: For individuals that appear to have a blockage, then doing a sonogram can actually provide insight into how severely blocked a carotid artery is or is not.
Elizabeth: Let’s turn from here to Circulation. Again, a heart-related study and something that I find really tantalizing and we have talked about before. This study is actually a randomized control trial just to see if giving people an inactivated influenza vaccine after they have had an MI, a myocardial infarction, or in a very small number of patients who had high-risk stable coronary heart disease, would prevent at 12 months a composite of all-cause death, a second MI, or stent thrombosis.
This is a really interesting thing because previous studies have suggested that providing an influenza vaccine to these folks would be a good idea. In this case, they took a look between October 1, 2016 and March 1, 2020 — 2,571 participants in 30 centers across eight countries, 1,290 assigned to the flu vaccine and 1,281 to the placebo.
All-cause death, I’m just going to cite that one, 2.9% in the group that got the flu vaccine. Almost twice as much, almost 5%, in the placebo group. Also increased rates of cardiovascular death and of MI, but just slightly more in the placebo group.
This is pretty persuasive that we ought to be administering an influenza vaccine and, of course, they also adjusted this seasonally for when the influenza virus would actually be circulating in these various countries. It still sounds like giving that when somebody is hospitalized is probably a good idea.
Rick: We have known that in people that have heart disease, influenza vaccination can prevent death and cardiovascular death. This is the first time where the influenza vaccine was actually given during a hospitalization. These are people that were having an acute heart attack. About three-fourths of them had a stent put in, a fourth of them were treated medically, and before they left the hospital they gave the influenza vaccine. It clearly reduces death and cardiovascular death by about 40% and future heart attacks by 14% with no additional risk at all. I think this is really good news. It ought to be a part of our standard armamentarium.
Now, having said that, these were individuals that had not had influenza vaccine in the previous 12 months and most of these individuals were ones that weren’t planning on getting it in the future.
Elizabeth: I find this really interesting from a biological plausibility standpoint. My question is, is there some hypercoagulopathy that’s represented by influenza infection, much like what we are seeing in many people with COVID these days? Could preventing that particular aspect of influenza infection be the mechanism by which this is working?
Rick: There are two possible mechanisms. One is it prevents an infection — that is influenza — that predisposes to inflammation and/or clotting events. The second is that maybe the shot itself is anti-inflammatory because we know that this causes an…