Dr John M

cardiac electrophysiologist, cyclist, learner

Would you know what to do?

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At its core, this blog aims to do some good. I don’t like to ask for things. It’s not why I write.

Today is an exception. I’m going to ask you to learn about and maybe support an important cause.

The topic is sudden cardiac death–our number-one killer. There are a lot of folks working on this problem. But few are more passionate than those who have felt the tragedy of losing a child to sudden cardiac arrest.

Here’s a picture of me (at HRS 2012) with two mothers from the Sudden Arrhythmia Death Syndromes Foundation–each of whom has lost a child to sudden death.

The opening scene was not quite this happy. Here’s how it went.

There I was enjoying a coffee in the booth of a defibrillator maker (full disclosure: the coffee was free), when three women came up to me and asked, “Are you Dr. John Mandrola?”

The initial sensations of pride–that someone actually recognized me–wore off in milliseconds. The next sensation was…uh-oh. Gulp.

I knew what was coming. A few weeks before the meeting, I had created a stir with a couple of posts (here and here) on why widespread ECG screening in the US would not be an effective way to prevent sudden cardiac death in young people. Numerous parents posted pictures of their dead kids on my Facebook page. I felt awful. It’s obvious that mothers’ who have lost kids to sudden death view the problem differently than an athletic doctor who bears witness to an epidemic of over-treatment and over-diagnosis of well people. There are few better examples of parallax–when the same problem looks differently depending on the viewpoint of the observer.

Here’s the thing about sudden death: Reasonable people, who share the same desire to prevent tragedy in young people, will disagree on the merits of widespread ECG screening. In fact, this month’s Heart Rhythm Journal features a point-counterpoint (For–Dr Sanjay Sharma and Against–Dr. Barry Maron) piece on the matter. Consider agreement on the merits of ECG screening as a mirage.

But there is one aspect of treating sudden death that we can all agree on:

The benefit of public education of early CPR and access to AEDs–Automatic External Defibrillator.

While at the European Society of Congress this August, I went to a session on sudden death in sport. A professor from France presented a study (great slides here) that showed how neighboring counties in France had widely disparate rates of sudden death. Regions with the lowest rate of death from cardiac arrest had instituted aggressive public education programs on the importance of early bystander intervention and had the greatest density of AEDs. The common denominator in all studies that look at sudden death is that early intervention with CPR and/or defibrillation improves outcomes. Here, there is near universal agreement.

Do me a favor. Take a minute to learn more about sudden death. Head over to the Sudden Arrhythmia Death Syndromes Foundation page.

Maybe even sign the petition to support greater access to AEDs. There are no significant downsides to improving public education on early CPR and greater access to life-saving AEDs.

You never know when you can give the gift of life to another.

Trust me. It will make you feel good.

JMM

The NY Times gets it wrong on ECG screening of young athletes

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When a news source as powerful as The NY Times publishes an article about sudden cardiac death in young people, one expects accurate information. It’s far too important a topic to write about imprecisely. This piece, entitled Should Young Athletes Be Screened for Heart Risk, included numerous inaccuracies and failed to tell important facts about the complexities of widespread screening of athletes. It was a really bad post.

I’d like to help clarify things.

Let’s state the obvious first. Few events in medicine–and life–pull at your heart more than the sudden death of a young person. As a Dad, it hurts just thinking about it. I accept that the tragic nature of the problem can cloud thinking on the matter.

As a heart rhythm doctor, I am tasked with diagnosing and treating conditions that could cause life-threatening arrhythmias. This is a tough problem. One reason is the rarity with which sudden death occurs in the young and outwardly healthy. Another is that sudden death rarely gives second chances. Its finality, therefore, motivates medical people to strive for 100% effective treatment. Again the obvious: whenever one strives for 100% efficacy, over-diagnosis and over-treatment become more likely. Never missing anything has steep costs.

Now, let’s get to the specifics of the Times’ misstatements:

On the incidence of sudden death:

As stated by author, Mr Anahad O’Connor…

“Once thought to be exceedingly rare, sudden cardiac death is far more prevalent among young athletes than previously believed, recent research has shown.”

Not exactly. The two scientific papers described as ‘recent’ were published in 2001. In fact, the lead sentence in the referenced policy statement from the American Academy of Pediatrics states, “in the [US], there is no centralized or mandatory registry for pediatric sudden cardiac arrest (SCA)…Available data generally are collected through media reports, from lay SCA advocacy groups, or from peer-reviewed publications, often from major referral medical centers.” In other words, we have no idea whether sudden cardiac death is becoming more prevalent in the young.

On who is at risk:

“While it can strike those who are sedentary, the risk is up to three times greater in competitive athletes.”

This statement makes athletics sound dangerous. Given our crisis in youth health, that seems unwise. Here’s another way of stating the known facts. The best peer-reviewed estimate available (Circulation, 2009) for sudden death incidence (US) in young people are that approximately 100 competitive athletes die suddenly per year. Considering the tens of millions participating, the actual death rate is 0.6 per 100,000 person-years. Keeping the things that threaten our youth in perspective, and even if we agreed on a three-fold increase in risk from competitive athletics, tripling the risk to 1.8 per 100,000 person-years hardly seems dangerous. The bottom line, which should have been written clearly, is that sudden death in the young is exceedingly rare—and three times rare is still rare.

At the risk of sounding unsympathetic to Ms. Varrenti, a grieving mom who started a foundation dedicated to sudden death after her teen died, I disagree strongly with her statement that…”it [sudden death] happens all the time.”

On ECG screening:

The rarity of sudden death in the young person directly impacts our ability to prevent it. Enter the debate about screening ECGs, which I have written about previously. This is where the Times gets it really wrong. First, on simple facts, they are way off on the price of an ECG. Just trust me: no one charges 1400$ for an ECG. Most often, it’s below 100$.

More importantly, the article overstates the benefits of the ECG as a screening tool. Though it is true that an expert electro-cardiographer may detect abnormalities in many of the underlying conditions (hypertrophic cardiomyopathy, Long QT syndrome and myocarditis) predisposing to sudden death, this doesn’t mean that’s what will happen in the real world. I respectfully disagree with family physician, Dr. Drezner, who stated that newer methods of ECG interpretation are better. If anything, ECG skills have worsened. The very human skill of ECG reading has gone the way of the physical exam. It’s not taught, appreciated or desired anymore. And despite what you may have read, computers cannot interpret ECGs accurately. (Not even iPhones) The under-detection of ECG abnormalities combined with the sharp rise in over-investigating normal findings will negate the rare finding of a potential abnormality.

Can we screen all athletes?

Dr. James WIllerson, the head of Texas Heart Institute, and beneficiary of a five million dollar private grant to screen 10,000 Houston-area kids, says “if we save even one life, it would be worth it.” That’s hard a statement to argue with. And it’s certainly easier to strive for such lofty goals with 5-million-dollar grants.

Here are some questions that Dr. Willerson should have been asked:

  • How would you know whether finding an ECG abnormality saved a life?
  • How do you measure the emotional costs of holding a kid out of sports?
  • Does prohibiting a kid from sanctioned athletics prevent him (or her) dying on a playground or at home?
  • Will you tell us how many extra heart tests (and complications thereof) will be done in the name of saving one life?

The Times should correct (or add too) this terribly flawed story. It’s important for the youth and parents of America to have accurate information about sports-related death.

I’m no journalist, nor a precise writer, but it’s really important that educators of the public understand what we were taught in medical school: No data is better than bad data.

JMM

P.S. I am not against the use of the ECGs in individual cases in which a doctor and patient understand the pre-test likelihood of abnormalities. Rather, these comments pertain to the widespread screening of low-risk populations.

CW: The mysterious athletic heart

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A very accomplished colleague of mine once mused—about an athletic patient with a heart problem:

“John…the guy is only a cyclist…It’s not like riding a bike is that hard.”

The ultimate in athletic hearts

I wanted to call him to the EP lab to feel how the heart of an endurance athlete rocks the catheter that you hold in your hand more than three feet away from the chest. I wanted to tell him about how your color vision goes black-and-white when you have to hold the wheel in front of you—just ten more pedal strokes, you say to yourself.

These thoughts arose after reading this very nice review (Circulation) of the athletic heart. It got me thinking about how much athletes perplex doctors.

Our hearts adapt to the increased demands of intense training by growing larger, contracting stronger, and more robustly responding to adrenaline. At the same time, skeletal muscles learn to extract more nutrients from the increased flow of blood. This is called fitness.

From the viewpoint of heart adaptations, there are two forms of exercise: endurance exercise (cycling and running) and strength exercise (weightlifting). Endurance exercise mostly involves sustained elevations of heart output which occur in normal (or reduced) states of blood vessel resistance. Strength training, on the other hand, involves short bursts of intense heart contraction with high levels of blood vessel constriction—think bench press. Many sports, cycling included, combine both forms of training.

The increased workload placed on the heart creates changes that can sometimes mimic disease. Athletes frequently re-define the limits of what is considered normal.

Here are a few things about athletes that often confuse both patients and doctors:

Heart Rate:

Athletes can develop very low heart rates at rest. This slowing occurs because training enhances the effects of the involuntary nervous system. Athletes develop incredibly active parasympathetic (vagal) tone, which results in slow resting rates. Medical people call this bradycardia. Heart rhythms for which the elderly require pacemakers are normal in the trained athlete. But beware athletes, there is some data out there hinting that heart-rate slowing from long-term endurance exercise might be permanent.

Left Ventricle (LV):

The left ventricle of the heart pumps blood to the body. Consistent athletic training induces the LV to enlarge. Strength (resistance) trainers mostly sustain increases in the thickness of the LV walls, while endurance athletes adapt by dilating the size the LV chamber. There is overlap, and most sports involve both types of changes. When correlated with body size (big people have bigger hearts), the degree of wall thickness and chamber dilation achieved in athletes rarely reaches the extreme.

Ejection Fraction (EF):

The most commonly used measure for the heart’s pumping ability is how much blood is ejected each beat. A “normally” contracting ventricle empties more than 55% of the blood in its chamber each beat.

A very surprising—but not uncommon—finding is when elite athletes show EFs that appear sluggish at rest. You look at it and think, “how is this possible?” Along these lines, I found this interesting study of Serial LV Adaptations in Professional Cyclists. French researchers reported that more than one-half of 286 Tour de France cyclists (1995 and 1998) exhibited unusual LV dilation, and 11% had abnormally low resting EFs. Although one can reasonably surmise that TdF cyclists in the late 1990s may have been more inflamed than those currently, the notion that extreme degrees of training may induce heart weakness is consistent with emerging data on exercise-induced cardiac scarring.

Left Atrium (LA):

The LA stores the blood after it returns from the lungs. It then ejects blood into the LV. Consider it the primer of LV contraction. The most common heart rhythm problem, atrial fibrillation, originates from the LA in more than 90% of cases. Endurance training is consistently associated with larger left atrial sizes. And since AF incidence trends with LA size, it is thought that LA enlargement is one of the reasons that athletes are at increased risk of AF.

Arrhythmia:

Abnormal heart rhythms observed in trained athletes span the spectrum of severity. Benign rhythm problems include premature beats, both from the atrium (PACs) and the ventricle (PVCs). Most of these nuisance beats keep the company of normal heart function and structure. Alas, more often than not, prescribed detraining rest decreases the burden of these beats.

Moving to the less benign rhythm disturbances, it is now clear that endurance athletes are at increased risk for AF. Though speculative, the reasons for this association are likely multiple: LA enlargement, inflammation, increased adrenaline levels, and enhanced vagal tone (vagal nerve stimulation induces AF in experimental models of AF).

Malignant rhythm disturbances, like ventricular fibrillation and sudden death, are well reported in both the lay press and clinical studies. There is little doubt that the extremes of intense training enhances both genetically pre-determined (Long QT, hypertrophic cardiomyopathy) and acquired (coronary artery disease) risks of death. When athletes show right ventricular disease, the risk of sudden death may be further enhanced. RV abnormalities, like dilation, scarring, or electrical conduction delay, warrant close attention.

Syncope (Passing Out):

The medical term for loss of consciousness along with loss of posture is syncope. Though visually dramatic, athletes that pass out (“done fell out” in Kentucky speak) have a mostly positive outlook. The most common cause of syncope in athletes is the benign faint—medical people call it by the crazy name: neuro-cardiogenic syncope or vaso-vagal syncope. This benign reflex can occur in anyone, but the frequent dehydration, high adrenaline levels and vigorous contraction of the trained heart make athletes especially prone to this common malady. On rare occasions, more sinister heart problems are the cause of syncope. Thus, it seems prudent that athletes who pass out should be evaluated by a doctor.

Performance-enhancing drugs:

No heart-related essay on athletes would be complete without mentioning performance-enhancing drugs. No longer are these agents confined to professional athletes. Numerous reports in the media have documented the use of anabolic steroids, erythropoietic stimulants (EPO), insulin, human growth hormone and pseudo-ephedrine in amateur athletes. Few scientific studies have been done, as finding athletes who admit to taking illegal substances is challenging, but it is well known that all of these drugs have potentially negative effects on the heart. I’m not pointing fingers here; the authors of the Circulation review, along with most reviews on the athletic heart mention performance-enhancing drugs.

Conclusion:

Athletes present a vexing problem to clinicians. Telling the difference between normal adaptations and disease is challenging, especially since emerging data suggests that for some individuals, an upper limit of exercise clearly exists. Call this a threshold level of training that when passed, results in harm.

I am a fan of the heart, and of athletes, and of what they both can do together.

The heart of an athlete is simply worthy of respect. Yes…Secretariat made me emotional.

JMM

A five-minute cardiac screen for athletes?

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It’s heart-wrenching when young athletes die of sudden cardiac death (SCD). This week, the death of Wes Leonard, a Michigan high school star athlete, was especially poignant since he collapsed right after hitting the game-winning shot.  This sort of tragedy occurs about one hundred times each year in America. That’s a lot of sadness.

The obvious question is: Could these deaths be prevented?

Let’s start with what actually happens.

Most cases of sudden death in young people occur as a result of either hypertrophic cardiomyopathy (HCM), an abnormal thickening of heart muscle, or long QT-Syndrome, a mostly inherited disease of the heart’s electrical system. Both HCM and Long-QT syndrome predispose the heart to ventricular fibrillation–electrical chaos of the pumping chamber of the heart. The adrenaline surges of athletic competition increase the odds of this chaos. Unfortunately, like heart disease often does, both these ailments can strike without warning.

Sudden death is sad enough by itself, but what makes it even worse for doctors (and patients) is that both these ailments are mostly detectable with two simple painless tests: the ECG and Echocardiogram (heart ultrasound).

Let’s get these kids ECGs and Echos then. Git-r-done, you might say.

On the surface the solution seems simple: implement universal cardiac screening of all young athletes. And you wouldn’t be alone in thinking this way. You could even boast the support of Dr Manny Alvarez of Fox News, and the entire country of Italy–where all athletes get ECGs and Echos before competing.

But America is not Italy and things aren’t as simple as Fox News likes to suggest.

There are three major flaws with Dr Manny’s simplistic proclamation that all (American) athletes should have pre-participation ECGs and Echocardiograms.

The Economic:

The estimated cost–in our current health care system–for adding an ECG and Echo to the sport’s exam is about $1000. That’s a bunch more than $19.99–the advertised price of the sports physical at my local grocery store’s walk-in clinic. Parents may be amendable to charging $19.99 to their credit card, but even when the safety of their teen is at stake, few can afford the current-day costs of ECGs and Echos.

Now, you could make the argument that 1000$ is ridiculously high. And you would own a valid point. But that argument goes to the heart of the healthcare debate.

Let’s consider this notion for a moment: I could listen to your teen’s heart, look at their ECG, place a hand-held ultrasound probe on their chest, and in a matter of five minutes I could clear them for competition. The ECG would exclude long-QT syndrome, and the Echo would exclude excessive thickening of the heart muscle. The reason why I could do this are threefold:

  1. My entire medical career revolves around understanding ECGs.
  2. I look at Echos nearly every day, and was schooled by one of its pioneers, Dr Harvey Feigenbaum.
  3. In general, I waffle a lot less than the average reader of subjective cardiac tests. (That trait might not be valuable at the Mayo Clinic, but it would be good for screening thousands of young people, who are normal 99.999% of the time.)

Ah, but that’s not how things work in our present health care model. Obviously.

You can’t just deliver quality care that easy. There’s got to be a certified technician and machine to do the studies–portable Echos will not work. Calling an Echo normal these days is totally insufficient, fraudulent even. There has to be a three page report documenting each section of the heart. And of course, I can’t officially read an Echo because I am not board-certified in Echocardiography, I am just board-certified in Cardiology and Electrophysiology.

It’s not just the high costs that make screening athletes problematic.

It’s the Math:

Why don’t the numbers support widespread cardiac screening of athletes?

Again, it isn’t as simple as Dr Manny suggests. He portrays ECGs and Echos as black and white, yes or no, high or low kinds of tests. That’s not even close to accurate. They are both highly subjective tests that require mastery of nuance, including the ability guts to call something “normal.”  When a young person’s life is at stake, shadows and innocent blips look much more sinister. Before guaranteeing the invincibility of a young athlete, doctors often see things on ECGs and Echos that “might be something.” Radiologists sometimes call these shadows “incidentalomas.”

That’s the rub with screening that Dr Manny omits. For every life saved by the screening test, there will be hundreds (perhaps thousands) of patients sent for more (and often highly invasive) testing. Doctors are not going to be wrong about sudden death in a young person. No way. No how. There will be more tests, not just because of defensive medicine, but also in the name of quality.

To the numbers: Rare diseases like HCM and Long-QT kill athletes at a frequency of about 0.01%. That’s the left side of the equation. On the right side of the equation are the risks of all the cardiac caths, electrophysiology (EP) studies and dye-requiring CT scans ordered as a result of the screening tests. Though an individual cardiac cath, EP-study or CT are low-risk, the cumulative risk of doing these on thousands of normal people surely approach the 0.01% chance of sudden death in an athlete. Said more simply, with made up numbers to make my point, if screening saves 50 of the 100 teens who die each year, but 50 die from complications that occur from chasing down incidentalomas, than it’s an expensive statistical wash.

The Reality of the Athletic Ethos:

The third major flaw with the idea that mandated cardiac screening will save lives is that making the diagnosis of heart disease doesn’t always equate to preventing sudden death. The athlete has to accept the treatment, which for them, like it was for Boston Celtic great Reggie Lewis, is often untenable.

Gosh, I wish we could save all the young athletes that die suddenly.

But the paradox of our present health care system is that awash in all its fury of available technology (the MRIs, the robots, the GPS-navigational-systems) is our inability to do simple things for the many.

That’s too bad.

JMM

P.S.: One thing that Dr Manny was spot on about was that more AEDs (Automatic External Defibrillator) in athletic arenas are surely a good thing. In the case of AEDs, there exists strong science to show that increasing their availability saves lives.