Who Needs a Defibrillator After MI? FDA Recs on Inferior Vena Cava Filters

TTHealthWatch is a weekly podcast from Texas Tech. In it, Elizabeth Tracey, director of electronic media for Johns Hopkins Medicine in Baltimore, 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 very early medication abortion, predicting who needs a defibrillator after MI, removal of inferior vena cava (IVC) filters, and the link between early sugar exposure with hypertension and diabetes.

Program notes:

0:40 Sugar rationing in first 1,000 days of life

1:41 Infant formula and solids

2:40 Divide in utero and post exposure

3:22 Sudden cardiac death after heart attack prediction

4:22 Something besides decreased heart function

5:15 Very early medication abortion

6:15 Rule out ectopic pregnancy

7:15 42-day period

8:16 OK if probably in the uterus

9:00 FDA recommendations on inferior vena cava filters

10:00 Removal is needed

11:00 Less likely to be removed in older people

12:18 End

Transcript:

Elizabeth: What’s the impact of early exposure to sugar?

Rick: Can we predict sudden cardiac death after a heart attack?

Elizabeth: Very early medication abortion.

Rick: And are we following the FDA recommendations in trying to prevent pulmonary emboli or clots to the lung?

Elizabeth: That’s what we’re talking about this week on TTHealthWatch, your weekly look at the medical headlines from Texas Tech University Health Sciences Center in El Paso. I’m Elizabeth Tracey, a Baltimore-based medical journalist.

Rick: And I’m Rick Lange, president of Texas Tech University Health Sciences Center in El Paso, where I’m also dean of the Paul L. Foster School of Medicine.

Elizabeth: Rick, because this one has garnered so much media attention, I’d like to turn first to Science. It was looking at the exposure to sugar rationing in the first 1,000 days of life in a pretty big population.

It’s a natural experiment because during the period of time when they were looking at in utero and early periods of somebody’s lifetime, there was sugar rationing in the U.K. Then they looked at what happened with those folks when they ended sugar rationing in September 1953. They look at these folks with U.K. Biobank data.

As we know, or maybe we don’t know, but current dietary guidelines recommend zero added sugars in gestation and up until age 2. However, here in our fine United States, the majority of children are exposed to excessive sugar, both through their maternal diet, while they’re in utero, while they are breastfeeding, and then even in the things that we provide them to consume, including infant formula and solids. Another daunting statistic is that pregnant and lactating women on average consume more than triple the recommended amounts of added sugar. This study took a look at this natural experiment, the end of a decade-long sugar and sweets rationing in the U.K.

What did it look like when we followed those folks out with regard to their risk of developing diabetes and hypertension? It’s that early life rationing reduced diabetes and hypertension risk by 35% and 20% respectively, and also delayed disease onset by 4 and 2 years respectively. It’s a pretty persuasive argument for there is a deleterious impact of eating too much sugar.

Rick: They even went a step further. They were able to quantify how much of this reduction in hypertension and reduction in diabetes was due to exposure in utero, and how much of it was due to excessive sugar exposure after the baby was born. In-utero sugar rationing alone accounted for about one-third of the risk reduction.

Elizabeth: We have been looking an awful lot at this sugar exposure risk and the constellation of things that it produces. It sure suggests to me that this is one of those things we need to very seriously consider and try to get out of foods.

Rick: Yep, think about it. We can reduce diabetes, hypertension, and, by the way, obesity by about 25% to 30% just by watching what we eat, the mothers eat, during pregnancy, and for the first 6 months after the baby is born. That’s pretty substantial.

Elizabeth: Why don’t we turn to the European Society of Cardiology?

Rick: There is a bunch of heart meetings going on. Can we predict sudden cardiac death after heart attack? Individuals that survive a heart attack are predisposed to developing heart failure in the future, having irregular heart rhythms, and sudden cardiac death. What you’d like to be able to do is predict who those individuals are because those individuals that have sudden cardiac death — and that’s usually due to irregular heart rhythm — we can put a defibrillator in.

These devices are expensive. You don’t want to use them if the individual is not going to be experiencing a sudden cardiac death. Typically, individuals that have had a heart attack and have markedly reduced heart function are the individuals we put a defibrillator in. About 80% or 90% of individuals with the defibrillator don’t actually use them.

What these investigators did — we have had over 20 different studies that have looked at over 140,000 patients, their clinical characteristics, demographics, medical history, EKG, echo, and some of these even magnetic resonance imaging, and we use something besides just decreased heart function to predict who is most likely to die. But most individuals after a heart attack don’t have markedly decreased function. There are more that die with mildly abnormal function than those that have severely abnormal function.

Do any of these other risk factors — these 80 different things that we look at — help decide who those individuals might be? The answer is no. Well, then even when you look at the individual with moderately or severely decreased function, again, are these 80 different things we look at besides just decreased function? No, they don’t do a very good job either. We still have a lot of work to do because you really only want to put a defibrillator in somebody that you think is going to need it.

Elizabeth: It just seems amazing to me that with this multitude of factors — and I’m sure they have cross-referenced and looked at all kinds of paradigms that might help to predict it — there is still nothing that shows up.

Rick: No. Again, 140,000 patients and 20 different data sets. Nothing else added any predictive value.

Elizabeth: Okay. Turning to the New England Journal of Medicine, this is a Swedish study that’s taking a look at very early medication abortion. Probably most of the folks who listen to this podcast know already that when a woman presents as pregnant, they typically will confirm that with an hCG test and often they look at ultrasonography to see whether they can actually visualize their pregnancy.

What this study does is look at women requesting medication abortion at up to 42 days of gestation. They randomized all of these women into two groups and either immediate start of the medications — their so-called “early start” group — or standard treatment where they delayed it until an intrauterine pregnancy was confirmed. Clearly, the reason they want to look at the intrauterine pregnancy confirmation is because they want to rule out those folks who might have an ectopic pregnancy where the hCG would still show that there is a pregnancy.

They had 1,504 women who were included in 26 sites in 9 countries, half of whom were assigned to the early start group, and the other to the standard group. Basically, they were able to show that virtually all of those folks — 95% of both your early start group and in the standard start group — were able to terminate the pregnancy successfully. They did note ectopic pregnancies in 1.3% of the early start group and in 0.8% of the standard group.

There were some complications that were the same, as would be expected, in this particular population. So, the early start without requiring confirmation and intrauterine pregnancy results in the desired outcome and doesn’t increase the risk.

Rick: There are many states now in the United States where they prohibit abortion in mothers whose conception has been 6 weeks or longer. This 42-day period represents that.

Those individuals they randomized to either early treatment with oral medications or waiting until they were confirmed — the concern is that if you didn’t know exactly when the pregnancy was and you gave this oral treatment it could result in increased complications. 750 received early oral medication and 750 received the standard care — that is, confirmation.

What they discovered, as you mentioned, is the results in terms of terminating a pregnancy were the same for both groups. That’s slightly higher complication rates numerically, but not statistically. But then when they broke it down — when they looked at individuals in whom, they said, “Well, it’s possibly in the uterus, but let us confirm it later” — those individuals could receive the medication safely. But if they couldn’t see it, if they didn’t know where, those individuals had a higher complication rate.

Now, the numbers weren’t large; they need to do a larger study. But even in their discussion, they mentioned, “Hey, we feel pretty confident if it’s possibly in the uterus that early oral medication is okay.” But they waffled a little bit when you couldn’t identify exactly because those are the individuals that may have a higher complication rate with oral medications, so I think that caveat is worth mentioning.

Elizabeth: Yeah. I mean, I think it is too. On the other hand, I would say that I think these results are pretty persuasive that almost all pregnancies, as we know, do implant in the uterus and so this notion that you’ve got to wait until you can actually visualize that, I just don’t think it holds water.

Rick: I agree with what you said, it’s most likely to be in the uterus. If it says “possibly” in the uterus or “probably” in the uterus, then I think it’s fine. Outside of that, I am not sure that there are enough data yet to assure that it is quite as safe as waiting for confirmation.

Elizabeth: Finally, let’s turn to JAMA.

Rick: Are we following FDA recommendations for treating individuals with pulmonary emboli, or preventing pulmonary emboli — that is, clots to the lung? Typically, clots to the lung most often occur because someone develops a clot in their legs and then it mobilizes to the lungs. It can cause sudden death and other complications.

Typically, we put these people on anticoagulation. There is an occasional individual in whom the blood thinners is contraindicated. One of the procedures that can be done is to put a filter in the inferior vena cava. The filter looks like an umbrella, so if the clot dislodges, it gets caught by the umbrella. It stays in the inferior vena cava, the large vein that leads to the heart. It never makes it to the heart or the lungs.

This is called an IVC filter. They have been around for decades, but actually when you look at the data there aren’t really very good data that it’s terribly effective. As a result, the FDA has recommended against using it unless the person can’t take anticoagulation. If you put it in, then the FDA recommends that you remove it soon thereafter.

How good are we at following the FDA recommendations? First of all, are we using fewer of these IVC filters? Secondly is, are we removing them like the FDA recommends?

They looked at 271,000 patients who had an IVC placed. Most of them were put in for the proper indications. It looks like we’re putting in fewer now than we were a decade ago. However, when they followed these individuals, those that had the filter, only about 10% to 15% of them actually had the filter removed. If you leave the filter in, it’s associated with complications — the complications being the whole inferior vena cava could thrombose. There is stasis of blood in the legs, you develop a clot in the legs, and those things happen in about 2% and 9% respectively. It’s a revealing study in that we’re putting in fewer and that’s good news. The trouble is we’re not taking them out in a timely fashion as the FDA recommends.

Elizabeth: Right. There are also risk groups where the filters are removed even less often.

Rick: Yeah. The individuals in whom they are less likely to be removed are older individuals, individuals with medical comorbidities, and African Americans. Well, those are the groups that are most likely to have higher complication rates with leaving them in, so that’s exactly the people you want to take them out. The message I would want to give to the practitioners that put them in is to make sure they are removed and to individuals that have one placed so they can talk to their physicians about that.

Elizabeth: Yeah. I’m wondering just about specifically those groups of people who are most vulnerable if they’re going to have enough bandwidth to really go to their practitioner and say, “Oh, by the way, did you put one of these filters in?” and “Let’s schedule its removal.”

Rick: Well, it’s interesting, as the median age in this particular patient population is about 75. It’s usually older individuals, but it’s oftentimes the older individuals that have a contraindication to receiving blood thinners and that’s why they put the filter in.

Elizabeth: People need to be aware of what’s going on and self-advocate, for sure. On that note then, that’s a look at this week’s medical headlines from Texas Tech. I’m Elizabeth Tracey.

Rick: And I’m Rick Lange. Y’all listen up and make healthy choices.