Welcome to Dr. Warrick's podcast channel. Warrick is a practicing cardiologist and author with a passion for improving care by helping patients understand their heart health through education. Warrick believes educated patients get the best health care. Discover and understand the latest approaches and technology in heart care and how this might apply to you or someone you love. Hi, my name's Dr. Warrick Bishop and thank you for joining me on my podcast channel. Today I'd like to talk about dilated cardiomyopathy and what to do if that dilated cardiomyopathy gets better. Well, first of all, what is dilated cardiomyopathy? Dilated is self-explanatory. It means enlarged or bigger. So we're talking about a bigger heart. Cardio pertains to the heart and myopathy is a word that means that's broken down to myo being muscle and pathy meaning a pathology or problem with function. So dilated, big, cardio related to the heart, myo related to the muscle, pathy problem with the muscle. So dilated cardiomyopathy means a dilated heart with poorly functioning muscle. Well, how do we measure that? Probably the most accurate way and the most common way that we look at that is how much blood the heart expels with each beat. Now, if you think about it, the heart's a globular chamber. Each time it squeezes, it doesn't squeeze completely and empty everything out. everything out in one squeeze, it would be ejecting 100% of its contents. While the heart doesn't have a 100% ejection of all its contents with each beat, what the heart tends to do is eject about 60% of the volume of the full heart with each beat. So a normal ejection fraction of the heart, or a normal percentage of blood expelled, with each beat, is about 60%. If the heart drops down to less than 40%, we would consider that, moving into the range of a cardiomyopathy, and if the heart is enlarged and not pumping properly, a dilated cardiomyopathy. With the cardiomyopathy becoming worse and worse, as the amount of blood expelled per contraction becomes less and less. Well, what can cause dilated cardiomyopathy? We know infection can, alcohol can, different drugs and particularly some chemotherapeutic agents can. A heart that's going far too fast for far too long can fatigue and dilate and not work properly as well. There can be genetic associations, so we can see it through families. And it can also be called idiopathic, which means we never find out exactly why it occurred. We treat dilated cardiomyopathy by putting people on different drugs, partly to reduce the blood pressure, because the blood pressure is the work that the heart has to do, and we want the heart to rest so it might recover. We also put the... patient on some medications to regulate heartbeat and alter some of the hormonal influences within the bloodstream. One of the agents we use for this are called beta blockers. They regulate the heart rate, stop the engine revving too fast so it can recover, and they block some of the sympathetic or adrenaline responses that can be associated. There are new agents on the market, which include combination preparations of Secubitril and Valsatin, and this is a very promising new agent that we're starting to incorporate into our therapeutic regime. When I went through medicine, we were taught that a third of dilated cardiomyopathy got better, a third got worse, and a third stayed the same. Having worked in the area now for over 20 years, my observation is that these teachings from many years ago were probably slightly on the pessimistic side. I'm thinking that through my own practice, I see more than 50 or 60% of people get some recovery. Maybe 30 or 40% don't change a lot, but only a few patients these days appear to deteriorate. in an unexpected and progressive, uncontrollable way without any response at all to therapy. So the good news is that many people with dilated cardiomyopathy will get some improvement. And we start to see that improvement at three to six months. We find that out by examining the patient, but also by repeating our assessment of how the heart is functioning. Remember I told you we look at the ejection fraction. The ejection fraction is best measured using an ultrasound of the heart. So we will often repeat that at three or four or six months after initial diagnosis and initial commencement of therapy just to see how things are progressing. Well, an interesting study called the TREND-HF study came out recently to help us. with our understanding of what to do if these patients appear to show an improvement. The TREND-HF study looked at about 50 patients with dilated cardiomyopathy, which was not caused by a heart attack, so caused by the sort of precipitance that I mentioned earlier, but none of them had had heart attack, which would leave a scar, and obviously that's a different process. Of these 50 patients, they evaluated what would happen if their hearts improved and with their heart improving, you then stop their therapy because, let's face it, they must be better. Well, they tested this out and this is a really important bit of research because time and again, I see patients who are feeling well and would like to know if they can come off their medication. Well, the trend HF group showed that with withdrawal of medications, nearly 40% of patients had a relapse, clearly demonstrating that in the setting of dilated cardiomyopathy, removal or withdrawal of ongoing therapy is just not a good idea. So even if the heart has recovered, there's now some convincing. data to suggest you really need to remain on those medications long term. Well that's a little bit of information about dilated cardiomyopathy. We've talked about the fairly recent trend HF study which shows you should remain on your medication even if your heart does return to near normal function for the long term. It is a condition which we've certainly improved our therapy for over the years. I hope you found that interesting and informative. Thank you so much for joining me and goodbye for now. You have been listening to another podcast from Dr Warrick. Visit his website at drWarrickbishop.com for the latest news on heart disease. If you love this podcast, feel free to leave us a review.
