PodMed Double T 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. A transcript of the podcast is below the summary.
This week’s topics include timing of aortic valve replacement, colchicine after heart attack, bedside ultrasound to diagnose increased intracranial pressure, and appropriate LDL levels after a stroke.
Program notes:
0:51 Use of colchicine after heart attack
1:51 A lot of experience with drug
2:49 Inflammasome
3:37 LDL targets after ischemic stroke
4:38 Lower cholesterol helped
5:36 Become the new standard of care
6:00 Timing of aortic valve replacement
7:01 Surgery within 2 months
8:01 Want a long-lasting valve
8:33 Bedside ultrasound to diagnose intracranial pressure
9:33 Optic nerve sheath swells
11:05 End
Transcript:
Elizabeth Tracey: Can we improve survival after a heart attack?
Rick Lange, MD: What’s the best cholesterol to shoot for after someone has had a stroke?
Elizabeth: If you have to have your aortic valve replaced, what’s the timing?
Rick: And diagnosing increased brain pressure at the bedside.
Elizabeth: That’s what we’re talking about this week on PodMed TT, your weekly look at the medical headlines from Texas Tech University Health Sciences Center in El Paso. I’m Elizabeth Tracey, a medical journalist at Johns Hopkins, and this will be posted on November 22nd, 2019.
Rick: And I’m Rick Lange, President of the Texas Tech University Health Sciences Center in El Paso, where I’m also Dean of the Paul L. Foster School of Medicine.
Elizabeth: Rick, in full disclosure, many of our listeners know already this is the American Heart Association meeting and that’s a gigantic meeting, so that explains why we are talking about a lot of heart-related issues. So I’m going to turn straight to the New England Journal of Medicine and say, “Can we improve survival after a heart attack?” This is looking at a drug, colchicine, after myocardial infarction and whether it can actually help people in their survival. They took 4,700+ patients enrolled, randomized them into two groups, one of whom received colchicine after their myocardial infarction and the other one a placebo.
They followed these folks for a median of about 23 months, and they looked for different endpoints which were death from cardiovascular causes, resuscitated cardiac arrest, subsequent MI, stroke, and they said, “Did we have any adverse events relative to the colchicine administration?” The upshot of the entire thing was that colchicine, a cheap drug with which we have a tremendous amount of experience, actually did lead to a significantly lower risk of ischemic cardiovascular events than the folks who were on the placebo.
Rick: Colchicine is a medication we have a lot of experience with because it’s used primarily to treat gout. It’s an anti-inflammatory medication, at least in small doses, relatively well tolerated with few side effects. This goes to the theory that inflammation plays a significant role in patients that have cardiac disease. If we can find an anti-inflammatory agent that’s well tolerated, inexpensive, we have a lot of experience with, can we decrease inflammation and decrease the risk of subsequent cardiovascular events? That’s exactly what this particular study shows.
Now interestingly enough, colchicine isn’t the only medication with anti-inflammatory effects. Statins, for example, also have anti-inflammatory effects besides just lowering cholesterol. This means that colchicine in addition to routine therapy may play a role in decreasing cardiovascular events. Again, inexpensive, well tolerated, and a lot of experience with it.
Elizabeth: Right, and so, of course, as you’ve already pointed out, these folks were on statins. I learned a new word in this particular study — the “inflammasome.” That’s a term I was not familiar with previously, so I thank the authors for educating me. And I guess I would also say I’m not really all that surprised, I guess, by the results of this study. How about you?
Rick: Twenty years ago I think I would have been surprised, because then we were just beginning to develop the hypothesis that inflammation plays a role. You might be surprised because it’s a relatively well-tolerated, inexpensive, readily available medication, and it decreased cardiovascular events over a short period of time. So in that respect, I think people may have been surprised, but there have been other antibodies, for example, anti-inflammatory medications that have been shown to be effective, also, but they’re much more expensive and not as well tolerated as colchicine in these doses.
Elizabeth: Okay. Let’s remain in the New England Journal of Medicine and take a look at one of yours, two LDL cholesterol targets after an ischemic stroke.
Rick: Since we’re talking about statins, that’s a good run-in to this particular article. What the authors did is they compared two different LDL cholesterol targets after ischemic stroke. Now you say, “Why would they do that?” Well, the current recommendations are not that we target therapy towards a particular LDL cholesterol level, but just that we put people on high-dose statin therapy. The dose of medication, the dose of statin depends upon which particular one is used, but the recommendations are, “Oh, just use a high-dose statin and not worry about the LDL cholesterol.” In fact, this study tested that and they took people that had an ischemic stroke, a stroke in the previous 3 months, or a TIA within the previous 2 weeks, and they targeted either an LDL cholesterol of less than 70 or an LDL cholesterol of 90 to 110.
They did that by either giving a statin to all the patients or a statin plus if they needed another medication, ezetimibe, to get it down to those target levels. They had almost 3,000 patients enrolled and they followed them for a median of about 3½ years. What they discovered was those that were targeted toward the lower cholesterol had a 22% lower risk of major cardiovascular events. That means another stroke or a heart attack or new symptoms that led either to urgent coronary or carotid revascularization or even death from cardiovascular causes. What this study shows is that targeting a lower LDL cholesterol — below 70 — is more advantageous than just giving a high-dose statin if we’re going to reduce subsequent cardiovascular events in people that have had a stroke.
Elizabeth: Let’s talk about the side effects.
Rick: All the patients were on a statin. About a third of those, those that needed to get to an LDL cholesterol below 70, had to take an additional medication. There was no difference in side effects between the two. About a third of the patients had some sort of a side effect that prevented them from getting either of the therapies, but pushing it to an LDL cholesterol of less than 70 had no more side effects than targeting an LDL cholesterol of 90 to 100.
Elizabeth: So, are you saying, then, that this will become the new standard of care?
Rick: I think it is. I think we have very good evidence, even on the coronary side, that getting an LDL cholesterol less than 70 may be more beneficial than just putting people on a high-dose statin, because even a high-dose statin alone doesn’t get people to that level.
Elizabeth: OK. Still remaining in the New England Journal of Medicine, let’s take a look at this study that I served up as when should you have your aortic valve replaced or the timing of that. They took a look in this study at 145 asymptomatic patients with very severe aortic stenosis. I have to admit that was a group that I thought, “My goodness, how often does that happen that you can have very severe aortic stenosis, but be asymptomatic?” They have a schematic that they present. They initially screened over a thousand patients with this condition; 758 of those had symptomatic stenosis, but 273, so between a quarter and a third, were asymptomatic. I thought that was just a real curiosity. I know you knew about that beforehand, but I sure didn’t.
In this case, they were trying to decide, “Gosh, if you’ve got that, can we just watch you and see until you become symptomatic and then replace your aortic valve, or should we just go ahead and do it?” In about half of them, they called them the “early surgery group.” They had surgery within 2 months after randomization, and there was no operative mortality in this group. The other were randomized to the conservative care group. In that conservative care group, the incidence of sudden death was 4% at 4 years and 14% at 8 years, while the group who underwent surgery early experienced much better outcomes. One of the things I’d like you to comment on is half of these folks got a mechanical valve and half received a biologic prosthesis, and I’m just wondering what your thoughts are on that.
Rick: As you mentioned, this is a group of individuals that have very severe, not severe, but very severe aortic stenosis and are asymptomatic. This is a relatively young group. They took people between the ages of 20 to 80, but many of the patients that we see with aortic stenosis are over the age of 80. They have other comorbidities and their surgical risk is higher. This is a relatively young group, and as a result, there were no surgical deaths.
The reason some got mechanical valves and some got a biologic valve — that is, a tissue valve — is the mechanical valves last longer. If you’re 30 or 40 or 50 years of age, you want a valve that’s going to last 30 or 40 or 50 years, perhaps. If you’re already in your 60s, 70s, or 80s, the valves last about the same amount of time, and so those patients get a tissue valve. The difference between the two is a mechanical valve you have to take anti-coagulation your entire life. In the tissue valve, that’s not the case. I think this does give us instruction about people that are relatively healthy. They’re low surgical risk, and even though they’re asymptomatic, if they have severe aortic stenosis, we should consider sending them to surgery early rather than waiting for them to develop symptoms.
Elizabeth: And that’s a great conclusion to that one. Finally, let’s turn to Annals of Internal Medicine. This is bedside ultrasound for diagnosing increased intracranial pressures.
Rick: This doesn’t relate to the American Heart Association, but I thought this was really very interesting because individuals that have some sort of traumatic brain injury or anything that could lead to obstruction of their cerebral vessels can develop increased intracranial pressure or increased pressure on their brain. You want to both diagnose that quickly because you want to relieve that to prevent any more permanent brain injury.
Now oftentimes, that involves imaging. You do a CT scan or an MRI. Occasionally, you can do a spinal tap to do that. It would be nice to make that diagnosis at the bedside doing something non-invasive, and this study suggests that bedside optic nerve ultrasonography can do that. That’s doing a sonogram of the eyeball, but you’re not looking at the eye. You’re looking at the optic nerve and the sheath around the nerve because that sheath is in communication with the pressure in the brain. When the pressure in the brain goes up, the optic nerve sheath swells. If it’s too big, that could potentially be a sign that someone has intracranial pressure.
To assess the accuracy of that, these authors looked at prospective optic nerve ultrasonography diagnostic studies to determine what the accuracy was. They looked at 71 eligible studies that included over 4,500 patients, most of whom were adults, but some were kids. They looked at the sensitivity and specificity. What they determined was in patients that had traumatic brain injury, the sensitivity was 97% and the specificity was 86%. Even those with non-traumatic brain injury, the sensitivity was 92% and the specificity was 86%. This says that if you know how to perform this particular test, it’s fairly accurate in determining whether someone has high intracranial pressure.
Elizabeth: When you compare this to other means of diagnosing this, what would you say?
Rick: Elizabeth, the major advantage is it’s done at the bedside. Now, again, a person has to have experience in using it and knowing how to make the diagnosis, but for places where someone may not have access to CT scan or MRI, let’s say you’re in a rural [area], being able to do this at the bedside is very helpful. It’s also less invasive than doing a spinal tap. That’s why I thought this was important.
Elizabeth: On that note, then, that’s a look at this week’s medical headlines from Texas Tech. I’m Elizabeth Tracey.
Rick: I’m Rick Lange. Y’all listen up and make healthy choices.
Source: MedicalNewsToday.com
