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. Rick Bishop and welcome to my podcast and videocastation. Really appreciate you tuning in. And I hope I can give you something interesting to listen to today. What I'd like to do is share with you some of my learnings from Cardiac Society Australia New Zealand annual general meeting and scientific meeting that was held in Adelaide in August 23. Well, there was plenty of stuff that popped up that was absolutely fascinating and I'm pretty keen to share it because... Well, it was just super interesting. So let me dig out my bits and pieces and run through a couple of little snippets that I've made notes on and I would like to share. The first was from a presentation that was given in a session titled Clinical Presentations That Worry the Cardiologist. And this particular... First topic that I'll speak about was presented by Raymond Sy from Victoria, and he was talking about a condition called long QT. Now, that probably means nothing to you, but let me refresh your memory. If you've ever heard of me talk about ECGs or anyone else talk about ECGs, you may well be aware that when we talk about ECGs, we talk about the electrical... characteristics of the ECG in a way that the first bump is referred to as a P wave. Then the next downward and upward and downward deflection is referred to as the QRS complex. And then there's another bump where all the electrical activity is pretty well getting back to where it should be. That's called the T wave. And then until the next heartbeat begins, which is another P, there's a, if you like, a neutral line. We call that an isoelectric line. So what I'm talking about is the QT interval. The distance between the spiky bit and the end of the T wave, which is the heart repolarizing. And that distance gives us some idea of the length of time that it takes for... the currents within the cells of the heart to move around and equilibrate over the membrane. Well I'm not going to get into the details of the lengths that we worry about other than to say that Around about 450 milliseconds makes most cardiologists look a bit concerned in terms of the length of that QT. And the reason why we get concerned is that we know that there can be risk of sudden cardiac arrhythmia as that QT interval lengthens. We know that greater than 500 milliseconds is really very problematic. Certainly concerning. The trouble with QT, though, is it can change during the day from day to day and in relation to different circumstances in an individual's life, which makes it super complicated. So, Raymond in his presentation was saying that one of the ways we can get around this is thinking about stress testing and looking at what the QT interval does when patients are... Firstly, standing as part of a stress test, but very importantly, looking at how the QT interval changes during the recovery period. The long and the short of this QT syndrome is it can be implicated as one of the causes of sudden cardiac death within families. And if there is a concern, it's a simple test to get a feel for whether that QT interval is long or not. Automatic reading algorithms on modern ECG machines will give you a very good idea as to whether that QT interval is prolonged or not, and it'll also calculate a QT interval that's proportional to the rate that the heart's beating, because as you might guess, the faster the heart beats, the shorter the QT interval has to be. Well, having said all that, one of the other interesting things that Ray spoke about, and this is probably not for general consumption, was that there's a difference between the beta blockers used. Now, I'd always thought that something like metoprolol might be ideal, but that's a very cardio-selective beta blocker, and his recommendation was natalol as an alternate agent, something that was more broad-based in terms of its beta blocking action. Importantly, he suggested that seeking medical advice and guidance from experts in the field who were involved with centres that specifically cared for these sort of patients is a pretty sensible thing to do at an early stage, and I can't help but agree. What I'd also like to talk about is a very nice presentation I went to by one of our colleagues here in Hobart, James Sharman, who actually presented the Guston Bauer Lecture. And the Guston Bauer Lecture is one of the titled lectures. And what a great tribute to James Sharman and his research for having the opportunity to present. And he presented on blood pressure, which is his area of expertise. He's based at the Menzies Center here in Hobart. And he's really regarded as a world leader in the space. Well, James shared a blood pressure odyssey, talking about not only his own journey towards finding out about blood pressure and understanding blood pressure more and more, but really also talking about the science, the medical community, and how we've observed blood pressures over the years. And very importantly, this concept of central blood pressure and trying to understand if we can... tease out what the blood pressure centrally, and that's within the aorta, if that's different to what's measured at the arm, what clinical significance does that have? Well, at the moment, I don't necessarily have a really good answer for you in that space. But one of the things that James flagged that I did want to share was that in Australia, Currently, at the moment, only 5% of home blood pressure machines have been validated against a standard, which I thought was absolutely astounding and really, to a large degree, makes us, well, makes us have to wonder how reliable those home blood pressure measurements are. I guess my take home from that for those who are listening who may well have a home blood pressure monitor is, A machine that's not being calibrated or validated to a standard may have some benefit if it continues to function at the same level because what we can use it for then is a comparator of an intervention before and after. So someone who's got a home blood pressure monitor may be commenced on a therapy and that individual may then be able to document quite clearly. that their blood pressures have dropped compared to prior. They may not be purely accurate measurements, because the monitor has not been validated properly, but the comparator before and after may certainly be valuable, and that would be information that I'd be interested in. Just on that note, when it comes to blood pressure, if you listen to any of my other podcasts, you'll know that I think it's super-duper important, and I tend to. go to a 24-hour blood pressure monitor as a gold standard to really help me understand what's going on with my patients over a 24-hour period. That gives us an idea of response to therapy, whether the blood pressure drops, how soon, how quick, to what degree. But it also gives us a really nice insight into what happens overnight. And this sort of information is super valuable, together with an identification of blood pressure that fluctuates a lot. Maybe people who have intermittent episodes at work where they're really very stressed. All this comes together and gives a great picture for someone like me trying to figure out the best way forward for an individual with their own blood pressure. One of the other things that James shared, and this is absolutely critical and flows on exactly from me talking about... using these 24-hour blood pressure monitors as a gold standard, is that only 32%, one third of patients who have high blood pressure, have that high blood pressure adequately controlled. Now that, to my mind, is appalling. That 60% of people running the risk of increased stroke, increased heart attack, increased atrial fibrillation, cardiac failure, renal failure, And we've got data now that tells us it raised blood pressure. It even drives dementia. So please, if you have any concerns about your blood pressure, get it checked out. And if there's still any uncertainty whatsoever, get a 24-hour blood pressure monitor or ask your GP to organise that through your local cardiological service. It's a super helpful set of data to help guide your best therapy into the future. I'm going to finish off this podcast with a quick comment on the complexities of pregnancy. And this was an interesting presentation that I caught and found it really quite compelling because there are real difficulties and challenges around looking after pregnancy-related issues patients who have heart problems of particular ilk. So one of the things in particular that was flagged was the presence of mechanical heart valves in patients who are pregnant. And you may not be aware, but mechanical heart valves require full anticoagulation and we use warfarin for this warfarin that blood thinner started its life as a rat poison. Now the problem with warfarin during pregnancy is that it can lead to deformities of the unborn child and so we want to get people off warfarin if we possibly can. So this particular presentation was all about trying to reduce the risk of complications around the management of mechanical heart valves in a pregnancy situation. And it seemed pretty complicated. Often we think about just swapping people over to low molecular weight heparin or sub-cut that's into the tummy or under the skin injections of heparin to thin the blood. But this has to be done. in a very controlled and a very careful way. What I learned was that if we are going to use low molecular weight heparin for mechanical heart valves in pregnancy, then we're obliged to test anti-10A levels, which give us a very clear indication as to whether we've got the... anticoagulation level right or not and this is super important for mother and child but it turns out as we get to later in the pregnancy low molecular weight heparin which has really quite a long half-life isn't the best option for the time of delivery we're still not able to use warfarin because that has a long half-life as well and so at that stage normal Well, what's the message there? If you're pregnant and have issues with your heart, please, please, please, before... Let me rephrase that. What's the message there? If you're looking to get pregnant and you have any issues with your heart, please, please discuss those issues with your cardiologist and obstetrician before embarking on that journey. It can be super complicated. If it is, it's super important that we have a heads up and know exactly what we're doing to make the journey as safe as possible for mother and child. I hope you've enjoyed this podcast on long QT, BP and pregnancy. For now, I'm going to wish you the very best. If you've got any queries or questions, drop us a note at info at drWarrickbishop.online. Thank you so much for taking the time to listen. I wish you the very best and hope you live as well as possible for as long as possible. Goodbye. 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'll give you information about risk and what else can be done to be even more precise.
