Welcome, my name is Dr. Warrick Bishop. I'm a cardiologist, an author and a keynote speaker. I'm CEO of the Healthy Heart Network. I'm all about trying to help people live as well as possible for as long as possible. Heart disease is huge in Australia. Every 20 minutes someone suffers a heart attack. Most of these could probably have been avoided if only we knew what to do. This podcast is all about helping you understand blood pressure, weight, cholesterol for better health. If you enjoy this podcast, I would be honoured for a five-star review. You can share it with your family and friends. It may well save someone you love. Hi, my name is Dr. Warrick Bishop and welcome to my podcast and videocast station. I really appreciate you tuning in and I hope I can share something with you today. that you find interesting and informative. Well, I've been sharing a little bit from Cardiac Society in Adelaide in 2023, so I've still got some more to share. And I thought I might combine two sessions. The first of those sessions was Contemporary Challenges in Sports Cardiology. And the other session that I'll roll into that is an EP arrhythmia one about syncope. Now I may have touched on syncope or blackouts previously, but I'd like to roll those two together because they have a bit of a thread. So let me kick off with a presentation about atrial fibrillation in athletes that was presented by Adrian Elliott from South Australia. As you're listening, you probably think, oh, exercise is good for you. And indeed it is. There wouldn't be a cardiologist in Australia who wouldn't encourage you to exercise if you had anything wrong with your heart. And even if you didn't have something wrong with your heart, we would love to see you exercise. So exercise in general terms is absolutely fantastic. that in a very select group of people who exercise a lot, there can be an increased risk of atrial fibrillation. Now, this is something that popped up probably five to ten years ago in the literature. We became aware that Even these people who were particularly fit and particularly well might run an increased risk of this condition called atrial fibrillation. Well, Adrian spent a bit of this particular session talking about why that might be the case. To be honest, it's not super well understood at the moment. It would be fair that when we look at exercise, for people who have atrial fibrillation, this is the normal population who develop atrial fibrillation, then there's no question that exercise is beneficial for those people to reduce recurrence of atrial fibrillation. So if you have atrial fibrillation, then it's a really good thing for you to be exercising as best you can. And there is good supportive data that you will reduce your recurrence risks. So if you're listening to this and have a bit of AF, And your exercise, good on you. If you can do a little bit more, that'd be great. The bit that we're talking about, though, is endurance athletes, where particularly in men and not so clear cut in women, these people can demonstrate an increased risk of episodes of atrial fibrillation. It's not really clear if that is associated with increased risk of stroke in athletes, and that's only because there's no studies to support that, but I don't think any of us as cardiologists would take the risk. Well, what might be the mechanism behind that? Well, significant endurance would increase cardiac output and increase flows through the heart. There is thought that there could be structural remodeling of the atria, i.e. that chamber gets stretched and therefore larger. It's possible that there's a change in vagal tone as well. And what I mean by vagal tone is when we think of the automatic or autonomic nervous system, the sympathetic nervous system is the fight or flight nervous system, ready for fighting or flighting. The vagal or parasympathetic nervous system is the rest and digest nervous system. And this may have a role in increasing funny heartbeats or atrial ectopy in these individuals. So training more turns down the sympathetic nervous system, turns up the parasympathetic nervous system, and that may give rise to atrial ectopic activities. Well, when it comes to managing athletes, they're not a great deal different to the rest. They will respond very well to pulmonary vein ablation, which is what we do for standard atrial fibrillation patients. We look to try and ablate that propensity to development of atrial fibrillation, and athletes respond well. to that as well, which is good. So atrial fibrillation link with endurance athletes, more men than women. There are some mechanisms suggested. There could be that risk of stroke, although that's not been shown in studies and they respond to the same sort of therapies. All good to know. The same session on contemporary challenges in sports cardiology had an Andre Laguerche present. He's very well recognized in cardiac circles, highly regarded nationally and internationally. And he spoke about risk of cardiovascular disease in athletes and spoke a fair bit about an observation, which is an increased calcium score in endurance athletes. Now, This has been flagged probably for the last 5 to 10 years as well, and it's certainly something that I've been aware of. Andre presented data around this, and although we don't fully understand it, I think we could make the assumption that endurance exercise may well lead to increased wear and tear within the arteries by virtue of the friction generated by the viscosity of hemodynamic forces that means that there are areas within those arteries that are being if you like damaged and if we think of coronary artery disease as the end stage of what begins as a healing process then we could quite easily suggest that Cholesterol moves into spots within the arteries where that wear and tear has occurred as a result of those endurance or prolonged events where that friction, if you like, from the viscosity of blood impacts on the artery wall. While there's no clear evidence that athletes... drop dead at a younger age even if they have increased calcium and we know exercise is a fantastic way to reduce your cardiovascular risk so it's possible that the other side of that coin sees a reduction in the deposition of fatty plaque or equally a rapid resolution of that fatty plaque and progression of that fatty plaque to stable plaque, which is less likely to cause a heart attack. And I think that's highly likely to be the case. So although we see increased evidence of calcification in long distance runners, it's possibly from the wear and tear of that exertion But the plaque that's developed is probably not the nasty plaque with large amounts of non-calcific plaque or cholesterol dominant plaque that we're liable to see that tends to rupture and cause catastrophic heart attacks. So yes, increased signs of wear and tear without the likelihood of significant adverse plaque features. Having said all that, my own practice tends to be not to make that assumption. But to combine calcium scoring, which is the non-contrast imaging of the heart arteries with CT scan, I combine that with a CT, using a CT scanner again, coronary angiogram, injecting dye or contrast to outline the artery in more detail so we can really see what's there rather than make an assumption. If you haven't read my book, Have You Planned Your Heart Attack? Please check that out. I cover that very clearly in there. Well, the sporting session was fantastic, and it was topped off by Professor Chris Samsarian, who, again, is a highly recognized figure in the cardiology world, both nationally and internationally. And he talked about the role of genetic testing in cardiac disease in athletes, covering such things as cardiomyopathy. i.e. problems with the muscle of the heart. Arrhythmia. I may have spoken about long QT syndrome before. That's what an arrhythmic problem is. Metabolic problems like raised lipid profiles. Congenital problems like, well, holes in the heart. And even troubles with the vasculature. Things that can affect the connective tissue. Things like Marfan's disease and Ehlers-Danlos disease, which you may not have heard of, but can lead to... Issues with the connective tissue and therefore with the arteries. Well, I won't go into too much detail about Chris's presentation other than to say it was precise, eloquent and extremely valuable. And I've taken some slides away from it so that I've got something to reference in my own practice down the line. And he really did make the point that there are a couple of key principles of genetic testing in sport. And I'll read out the do's. You can imagine the don'ts yourself. But the do's were get the clinical phenotype right. So make sure you know what you're looking at before you go on to genetic testing. So the phenotype means what does it look like? Everyone needs pre-test genetic counselling. This is really important. And I think it's a great blanket rule. There's very few blanket rules in medicine, but before genetic counseling, sorry, before genetic testing, genetic counseling should be one of those blanket rules. It is therefore important to understand the pre-test probability of that genetic testing. And it's always important in this particular space to have an expert in genetic cardiology available. So a fascinating presentation given by Chris Samsarian and talk about the importance and the value of gene testing in athletes. Well, I'd like to move on to one of the other sessions and one of our other speakers because it was about sudden cardiac death in young people. And that was presented by Liz Peretz, who works... in the Baker IDI, Melbourne, in fact, with André Le Gersh, who I just mentioned. Now, Liz has been very involved in the research of sudden cardiac death and pulling together the information that allows us to understand why this is occurring. The cut-off for sudden cardiac death in young is considered about 35 years of age. And when we look at the cohort of sudden cardiac death, which occurs at a rate of about 20,000 to 30,000 per annum in Australia, we see that coronary artery disease is, in fact, the most common cause. And we historically used to think that coronary artery anomalies or abnormal course of coronary arteries was A common cause of sudden cardiac death, i.e. a major coronary artery that took a circuitous course and maybe had a bend in it, when a young person exercised, that bend would lead to a lack of blood flow, irritability of the heart, and a funny rhythm. Well, it turns out that that was really not what was found on autopsy data. As it turns out, for the last decade or more, Victoria in particular, leading the rest of Australia, and now Australia is on board, have been looking at compulsory autopsy of young sudden cardiac death. And coronary artery anomalies have turned up to not be a risk factor at all. There is an increased risk of sudden cardiac death with exercise. The statistics would say that coronary artery disease is... the leading cause, but drug toxicity is the next. Behind that, there isn't a cause found. And then it's things like non-ischemic cardiomyopathy. So these are things where the muscle of the heart is impacted in some way. Then it can be from respiratory causes, neurological causes, gastrointestinal causes, and so on. So, a complex bunch of causes for sudden cardiac death in the young. They've even done some monitoring in this space to try and predict who could and who couldn't be at risk. But unfortunately, even with monitoring, they've been unable to get clear answers on exactly what's going on. The take home from me was that this is a complex space. Drug toxicity is super important and whatever we can do to improve our society's use and appreciation of drugs could only be to the good. But the other thing that really struck me was the significance of coronary artery disease, even in this young cohort. And we know that these people are people who are suffering from the condition of familial hypercholesterolemia, and I believe it really forces us to sharpen our pencils and identify these people through family tracing, genetic testing, cascade screening, and implementation of early therapy, which will almost certainly have a significant impact on the risk of these people suffering sudden cardiac death at a young age. Well, I'm going to wrap it up there. I hope you found this podcast informative. If you have any queries or questions, drop us a line at info at drorickbishop.online. For now, I'm going to wish you the very best. I hope you live as well as possible. For as long as possible, take care and bye for now. Did you know that coronary artery disease kills one in four people? So most of us... are likely to carry some risk or know someone who does. If you're interested in finding out more about how to evaluate that risk, check out www.virtualheartcheck.com.au. It will give you information about risk and what else can be done to be even more precise.
