Is this the most important cardiology study of the last decade?

In recent years, progress in the field of cardiology has been painfully incremental. We have enjoyed small gains–a better ablation catheter and mapping system, a couple of new anti-platelet drugs, maybe better stents, and even the highly touted anticoagulant drugs are within 99% in efficacy and safety of warfarin. Major breakthroughs, though, are non-existent. (And please don’t tell me squishing valves in the frail elderly is a major advance.)

This absence of game-changing type progress has an explanation. Perhaps the answer will be obvious after I tell you about the most important cardiology medical study of the last decade.

Its title includes atrial fibrillation but it is much more than a rhythm study.

Screen Shot 2014-08-27 at 6.03.14 AMEffect of Weight Reduction and Cardiometabolic Risk Factor Management on Symptom Burden and Severity in Patients With Atrial Fibrillation–A Randomized Clinical Trial

This is a trial of a novel treatment strategy for atrial fibrillation. Patients enrolled in the study were overweight Australians referred to an urban arrhythmia center in Adelaide for symptomatic AF. The researchers compared an intensive (physician-led) intervention approach to weight reduction and risk factor (high blood pressure, sleep apnea, alcohol intake, diabetes) management to the standard of care.

The study was born from two facts: One was that there is a long waiting list to get AF ablation in Australia. There was time. The second was that this group of researchers previously discovered (in a sheep model of obesity) that weight reduction had beneficial rhythm and structural effects on the heart. If it worked in sheep, it would likely work in humans, went the thinking.

Patients in the intervention group were referred to a specialized clinic (not an arrhythmia clinic) where a team worked with patients on basic health measures. This meant strict attention to calorie reduction for weight loss, including meal replacement if necessary. It also meant attention to blood pressure, sleep apnea, blood sugar control, lipid lowering and alcohol and smoking cessation. The control group also got excellent care; risk factors were treated and patients were given good advice on losing weight.

I know what you may be thinking: This does not sound like electrophysiology; it sounds like general internal medicine. And it is–and that is the point.

What makes this trial so important are the results–and the implications of the results.

The trial is free on the JAMA website, so you can read it yourself. There is also a 6-minute podcast with senior author, Professor Prash Sanders. Here are the study’s major findings:

  1. BMI and waist circumference decreased in both groups, but the intervention group lost much more. (Patients in the intervention group lost–on average–6 inches in waist circumference.)
  2. AF symptom burden and severity in the intervention group dropped significantly after 3 months and the curves continued to separate over time. (The graphs are impressive. See Fig 2.)
  3. 7-day ECG recordings from the intervention group, taken at baseline and 12-months, revealed significantly fewer AF episodes (3.3 to 0.62) and shorter duration of episodes (1176 min to 491 min). No significant changes were seen in the control group.
  4. On echo, left atrial size and volume, posterior wall thickness, and myocardial mass all decreased significantly in the intervention group. (This is a huge point because it provides a mechanism for improvement.)
  5. Cardiometabolic risk factors improved in both groups, but there was a significant decrease in numbers of patients with high blood pressure, elevated lipids, and alcohol consumption greater than 30g/wk in the intervention group.
  6. Pill burden decreased in the intervention group and increased in the control group.
  7. Catheter ablation was performed in 14/75 patients in the control group compared with 10/75 in the intervention group.

Yes, it’s a small study from one center in Australia. But look at those findings; look past the AF reduction. Think big picture. Consider what these results say about the practice of medicine. It is so clear to me.

For my entire career, the default has been to treat risk factors and late manifestations of disease. We prescribe medication for high blood pressure and diabetes. We ablate the left atrium to treat sources of atrial fibrillation–the irony being that scar leads to AF and burns/freezes create scar. The reason we do all this treating is because we fail to see these diseases as unnecessary. We don’t think it is possible, or worse, we don’t trust people to make good choices. And this failing is mostly on us physicians.

These researchers have shown both doctors and patients that it is possible not to have lifestyle diseases. They have given us proof that, if you try hard enough, structural heart disease and blood vessel disease and insulin resistance may be reversed. The key word: motivation.

Here is where the skeptics come in. They point out that these sort of results are not possible in the real world. They say: in developed societies where food is abundant and technology makes life easy, weight loss is hard. Really hard.

Okay, I get that. But why is it so?

One reason it’s so hard is because the medical establishment collectively gives in. Look at this Tweet from Dr Rajeev Pathak, one of the Australian researchers.

Respect, teach, and convince patients. These are our major roles as professional caregivers. To doctor is to teach. We aren’t just technicians and medication prescribers.

Of course there will always be a need for treating disease. We will need skilled ablation docs as there will still be AF. We will need interventional cardiologists because there will still be heart attacks. And so on for all medical fields. But we have to stop ignoring the obvious.

Respect. Teach. Convince. What makes this study so damn important is it that should change an entire way of thinking about treating people.

And now you can see why progress in cardiology has been incremental. It’s because there are no more antidotes to living so large.



  1. Nice post.
    Good ammo for my wellness practice.
    But besides doctors teaching patients, we also need cardiologists to allow the family docs and internists to do their preventive thing and not continue the “lifestyle changes don’t matter, only we cardiologists can help you” guidance to our mutual patients.

  2. Hi Dr. John

    As a heart patient and former distance runner for decades, I’m not at all a “skeptic” about the proven value of healthy eating, regular exercise and cardiac risk management strategies. Nor do I disagree with Dr. Yoni Freedhoff (author of “The Diet Fix: Why Diets Fail”) who once wrote that, no matter how you exercise, “you can’t outrun your fork!”

    I am, however, a realist.

    And there is nothing even remotely realistic about a study (or any doctor’s advice coming out of this study) that suggests patients should adhere to a severely restrictive 800-1200 calorie/day diet longterm – on top of all the other daily “compliance” decisions recommended in this study.

    As you know, it was that extreme 800 calorie number that threw me for a loop. (Well, that plus the study’s published “over 50% dropout” rate statistic – although Prof. Sanders corrected that with a confusing Tweet yesterday that said the “dropout rate was much less than that……we reported early as the findings were so significant.”

    Another confusing Tweet from Prof. Sanders was the one implying that symptomatic AF is a “strong motivator” to make the significant lifestyle changes observed in this particular study. If this were actually true, you wouldn’t need to be writing this post, Dr. John – because all of your overweight AF patients would be easily “motivated” to put themselves on extreme diets just as the intervention group of this study were – and you know that is, sadly, just not the case.

    If symptoms were all it takes to become “motivated”, then every smoker who hacks and coughs their way through their pre-breakfast cigarettes would already be very motivated to quit.

    We already know that, certainly in the long run, very low-calorie diets are NOT more effective than more modest calorie-reduced diets in weight loss. Personally, I’d like to follow those 75 folks in the study’s intervention group a year from now when their participation in this study is but a dim memory to see how many are still successfully relying on “meal replacement” food substitution, or how many have regained their monitored weight loss – and then some.

    Call me skeptical – but I suspect I’m merely trying to inject a dose of reality here.

    1. I’ve read that afib ablation bills run in the 80k-100k range here in the US (Am I way off? I don’t know for sure). Consider how much ‘motivation’ you can buy for that kind of money.

      You could have someone plan and prepare your meals, watch you eat them, and buy groceries for you. You could pay someone $100 a day for 6 months to stick with the program.

      You could send a film crew to interview family members and create motivational videos. How many people are you really going to eat that extra serving when their granddaughter is asking them to stick around and watch her grow up?

      I’m not saying any of that will happen, but the potential to provide ‘motivation’ is incredible when you’re dealing with that much money per patient.

      Motivation _is_ tough, but the science behind what makes motivation work for different people has really improved over the last 15 years. If we could implement some of what we know will work so some people, I bet the savings would be staggering.

      My confidence that the medical-industrial establishment will have any interest in pulling it off? Well, it’s a bit on the low side…. That may be where the real motivation problem lies.

      1. J, C, J et al.

        The focus of my piece was to show that the science is now there. Doctors can believe that reversal of lifestyle diseases, especially AF, which was previously thought to be incidental, is possible. This is big because most doctors don’t believe it. In the real world, if you start talking about lifestyle reversing disease, you get looked at as a nut. I get away with it here, in this small pond, because I’ve had time to build enough capital to oppose established thinking. It is no small thing to send an AF patient back to a referring doctor with only education and no procedure.

        Yet, I am convinced. Dr. John Day, president-elect of HRS, is convinced. But in the medical world, such thought-change comes slowly.

        Your comments about costs and medical establishment highlight another reason why paradigm change is hard and slow, especially in the US. Namely, human nature and incentive. You are correct; bills for any ablation procedure are in the $100,000 range. Though charges don’t equal costs, it is a lot. Hospitals are paid to do things. Doctors are paid to do things. Pharma and industry are paid when doctors and hospitals do things. In our current system, caregivers are financially penalized when patients help themselves.

        My case is instructive. Over the past year or so, I have done fewer AF ablations. A hospital staffer even asked me about it. “John, what’s going on with AF ablation, the numbers are down?” I have followed the Adelaide (and others) work for a number of years. And, in my experience, anecdotal and unpublished as it is, they are 100% spot on. The reason I’m doing fewer ablations for AF is because AF gets better when people treat themselves better. But…

        This kind of approach to AF takes time. My wait for doing a procedure is weeks, but it is months for an office visit. An office visit with a typical AF patient requires endurance. I’d even say, after more than 700 AF ablations, a couple of new office consults for AF are more stressful than a left atrial ablation. And now my salary is way down–which is okay for me, but not for others. (I often joke that I am the only doctor in Louisville trying to make less money.) The point is: I am financially penalized for practicing minimally-disruptive cost-effective medicine. And anyone who practices this way in our current system is financially penalized. Now that is nuts!

        This is why I feel bundled payments and capitation will enhance the care of patients with AF. Yes, we will have to be mindful of excessive rationing, but at least then, all parties will be incented to turn to the ‘fury of medicine’ only when basic health measures fail.

        1. To be honest, I’m quite surprised that so many Doctors would dismiss the idea that lifestyle changes can reverse disease. It seems so obvious. I’ve read quite a few studies, and I’m a pretty skeptical guy. This one is convincing.

          If people do look at you like you’re nuts, all the evidence in the world might not be enough.

          Malcolm Gladwell gave a talk about how calls for more evidence can be used to maintain the status quo. People seem to care more about the football portion of his argument, but I find the black lung story to be more interesting and relevant.

          The financial incentives shared by the coal industry, college football, _and_ the our current health care system are striking. It’s HARD to do the right thing when you have every incentive not to. It’s much easier to demand more evidence.

          The talk is an hour, but worth watching:

          You can get a quick outline of his argument in the first half of this article:

    2. One can eat a 1200 kcal very low fat plant-based diet and be quite satisfied. It sounds extreme, but cravings for fat and sugar are greatly reduced on this diet and weight comes off easily. For weight maintenance most can simply follow a plant-based whole foods diet and do not need to count calories. I recommend supplementing with B12 and freshly ground flaxseed (the latter helps maintain satiety).

      Yes, one will be hungry during the first few days until circulating insulin levels decline to match the new diet which is much lower in simple carbohydrates. Tastebuds adjust to enjoy the new flavors (which usually include a lot of lemon, garlic, onions, and herbs) in 1-2 weeks. In addition, the fresh food takes extra energy to digest.

      On the other hand, eating 1200 or even 2000 kcal of a Standard American Diet full of processed carbohydrate and ~30% fat leaves me (a remarkably tiny person) feeling ravenous. I can easily stay full on as little as 800 kcal of nutritionally dense vegetables, beans, and unprocessed whole grains without any need for calorie counting for weight maintenance purposes. It does take some planning, but habits can be formed.

      The Healthy Librarian, a medical librarian from the Midwest, has some great tips on how a “normal” person (and family) can adopt this diet, thrive, and love the food, too. Here is her frequently updated Facebook page:

  3. I thanked you for “not blaming the patient”. Premature?

    I understand that the brunt of your patients might well have become unhealthily FAT. (Any other descriptive is an obfuscating euphemism!)

    Each “patient” is a discreet individual, however. You gotta take into account the exceptions as well. We’re important as well.
    As a matter of fact, accounting for the extremes and exceptions in any mass problem like this is probably the best route to discovering the ultimate underlying mechanism.

    Genes? Gene expression?

    Account for the grossly life-style negligent “subjects” who don’t get violently symptomatic AF and then you’ll be getting somewhere.

    1. Jeff-

      Can I encourage you to re-read the study? Especially Fig 1 and Table 2. The authors track each patient outcome, and make it clear that not everyone experiences the same result.

      As a group, the treatment side experiences remarkable improvements, but there is a clear sub-group that continues to have afib episodes even with the lifestyle interventions. Their episodes are fewer and shorter, but no one is suggesting that the treatment cures everything for everybody.

      In other words, the ‘exceptions’ are in there, and they are accounted for. Imagine the time and brainpower your EP could spend on the toughest cases when the number of people in the waiting room has dropped from 49 to 9! (Table 2) This is good news for _everyone_, even (especially!) those with stubborn cases.

      1. It’s true that the exceptions you have in mind are shown to be there, which is not the same as accounting for them – in the sense of showing causes; reasons for the difference.

        We all come to this site looking for insight and/or relief for our own personal reasons. My personal “exception” is that my BMI has never been above 2.1. I’ve never experienced the fallout from overindulgence and obesity, namely, all the other risk factors that Dr John lists above.
        Severe paroxysmal AF anyway. There’s a reason. What?

        That’s me; why I’m here.

        1. @Jeff: Your posts suggest you may be a highly conscientious (maybe even with “type A” leanings) person. If so, perhaps that is a contributor. Or maybe I have misread your words and you are actually a Zen Master-in-training. One can always find unlucky folks who don’t have any obvious risk factors for their diseases.

          1. Yeah, conscientious, I guess. Thanks, pgyx.

            I get a little cranky when I’m discounted and set aside for not fitting the norm (AF is just one example) otherwise I’m pretty mellow.

  4. What’s the mechanism BEHIND these results that seem to benefit across the board, at least to some degree?
    Reduction of fibrosis or scarring?

    1. I wonder if there is at least a component of improved blood flow (by virtue of less vascular disease) to the heart’s electrical system. It doesn’t take much vascular disease to clog a vessel’s tiniest distal (end) branches. Just about every body tissue & system tends to regulate itself more effectively with the right amount of blood flow.

  5. This post made me wonder if I am missing something in the Australian Study. By now, it is no secret that healthy living, including exercise, is beneficial and I predict that similar studies will be done to prove its benefit in conditions ranging from Alopecia to Zygodactyly. What I found more interesting was that patients in Australia cannot just interrupt their usual toxic lifestyles with a brief visit to the cardiologist to fix whatever is wrong and then continue unabated with the same habits – they appear to be forced to explore other options inluding exercise. Perish the thought! I do however, find Dr. John’s reflexive blaming of the medical profession for not changing patients’ lifestyles old, outdated and simply wrong. How sad to read that all the money spent on new catheters was done for something that may be marginally better, on drugs that is 99% as effective as Coumadin, only 1000’s of times more expensive! How sad and what a waste! But to come back to us culprits: I – like most of my colleagues – spend a large proportion of the time in my Primary Care office talking about diet, exercise and lifestyle changes. I even run one hour most days of the week in the town I practice during lunch hour so that my patients can see that even a slob like me can do it and become healthy! So please do not include me in that generalization. The problem is a system that works perfectly, it is not broken – it rewards patients to be unhealthy and I explain it here: To quote another Cardiologist:
    “People just do not do things because they are good for them. And are even less inclined to do so when they enjoy doing the opposite.” George Sheehan. “Running & Being.” Rodale Press, 2013. iBooks.

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