**EP09: Treadmill Drugs and Preparation** **Dr. Warwick:** Welcome to Dr. Warwick's podcast channel. Warwick is a practicing cardiologist and author with a passion for improving care by helping patients understand their heart health through education. Warwick 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. I'm Dr. Warwick, and I'd like to welcome you to my consulting room. Today, I'd like to talk about treadmill testing and, in particular, the preparation that you may need to undertake with regard to treadmill testing and your medications. We do plenty of treadmill tests through here; that's a big part of the service we provide. It's not uncommon for me to have patients come in thinking that they've done the right thing by either stopping their medication or taking medication before the test, and they're not exactly sure what's right and what's wrong. I'm going to try and explain that today. When we do a treadmill test, there are really two main things that we're looking to find out. In one situation, we're trying to see if a symptom of chest pain or shortness of breath is related to the heart. So, we put a patient through a treadmill to invoke exercise because their history has been one of chest pain or shortness of breath on exercise. If we're able to reproduce that symptom of shortness of breath or chest pain during exercise, and we can demonstrate an abnormality of the heart—either by the ECG being abnormal or when we ultrasound the heart, seeing that the heart doesn't move normally under load, indicating a lack of blood flow—then we can confirm the diagnosis that lack of blood flow is the cause of the symptom. In that situation, the treadmill test is a diagnostic test. So, one of the reasons we do treadmill testing is for diagnosis. In the setting of diagnosis, we want as much information as possible, and we want the clearest information possible to make that diagnosis. We don't want anything clouding the water. We want the patient's heart rate to go as high as possible, and we want a really good feel of the patient au naturel. Almost invariably, we want the patient off any medication that could slow their heart rate down when we're doing a diagnostic test because slowing the heart rate down will make the test less precise, and we might be less able to pick up that abnormality because the test is less sensitive. So, for diagnostic tests across the board, if you're on a tablet that could slow your heart rate down, please check, because there's a very good chance whoever's doing the test would want you not to be on it in the days leading up to that test. This way, they can see your heart in its natural state and get your heart rate up as appropriate to give them the best sensitivity of the test and provide you with the best information. Well, stress testing for diagnostic purposes—that's the first reason we do it. The second reason we do it is for prognosis. Prognosis is to tell how well you're going to do in the long term. In the prognostic setting, more often than not, we've clearly indicated or defined or diagnosed that there is a problem with the arteries, some sort of flow limitation. It may be someone who's had a stent, had a bypass, or had a CT scan. There's evidence that we know that there may or may not be a blockage there, and we've put the patient on treatment to manage that. In the prognostic setting, what we're interested in finding out more often than not is how does this patient behave in the real world on their usual tablets when pushed to a high workload? So that if, on their medication at a high workload, the heart appears to be working well, we, as the doctors, can be reassured that we've got that patient's heart well protected. So, in the prognostic setting, we generally want to see patients not miss any of their medications because those heart rate regulators and those anti-anginal tablets—the tablets that affect how the heart works and reduce the impact of shortness of blood flow—are the very things we're trying to check and make sure are working properly for that individual. We want to check, for example, as well, that we've reduced that patient's symptoms so that their chest pain or their shortness of breath is markedly improved based on the therapeutic intervention. So, generally, in the prognostic setting for stress testing, we want you on medication. Diagnostic: off medication; prognostic: on medication. Not sure? Please ask. It's only a phone call, and we'd love to tell you. I hope that makes a bit of sense. Thank you for joining me, and good health. You have been listening to another podcast from Dr. Warwick. Visit his website at drwarwickbishop.com for the latest news on heart disease. If you love this podcast, feel free to leave us a review.