Chronic total occlusion (CTO) of the coronary arteries occurs when there is complete or nearly complete blockage of one of the heart’s arteries for 30 days or longer. It is caused by chronic build-up of artheroscleroic plaque inside the artery.
Dr. Nasser Khan, cardiologist, explains the cause, prevention and treatment options for CTO.
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Chronic Total Occlusion of Coronary Arteries and How to Treat It
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Learn more about Nasser Khan, MD
Nasser Khan, MD
Nasser Khan, MD is a practicing Cardiologist (Heart Specialist) in Bakersfield, CA. Dr. Khan graduated from Allama Iqbal Medical College, University of the Punjab in 1988 and has been in practice for 29 years.Learn more about Nasser Khan, MD
Transcription:
Chronic Total Occlusion of Coronary Arteries and How to Treat It
Bill Klaproth (Host): Chronic total occlusion or CTO is a common heart disorder in many patients with coronary artery disease. So, what are the causes, how can you prevent this and what are the treatment options? Here to talk with us about chronic total occlusion of the coronary arteries is Dr. Nasser Khan, a cardiologist at Dignity Health. Dr. Khan, thank you for your time. So, what happens with chronic total occlusion of the coronary artery?
Nasser Khan, MD (Guest): Yes, thank you very much for giving me a chance to talk about this very important topic. Chronic total occlusion in the layman’s term means that there is 100% blockage in one of the main arteries of the heart which has been there for longer than three months. Previously, it has been a somewhat undiagnosed, undertreated and difficult to treat disease but now with improvement in techniques and some new tools in our hands, we are able to offer treatment for these lesions.
Bill: So, Dr. Khan, you just mentioned that this is underdiagnosed and undertreated, so potentially, many people suffer from chronic total occlusion of the coronary arteries. Is that right?
Dr. Khan: That is correct. So, in many studies, it has been shown that people who undergo angiograms routinely for either symptoms or no symptoms, who undergo angiograms, we have discovered that if a person has a 50% blockage in the heart in one of their arteries, there is a 25% chance that they have another blockage with is at least 100%. So, bottom line is, that the prevalence rate is anywhere from 20-25% in patients who have some blockage in their heart. They will also have 20-25% chance of having a 100% blockage also during the same angiogram.
Bill: That’s amazing. So, I’m thinking of the coronary artery in the neck going up to the brain, so you are saying that could be totally occluded, totally blocked?
Dr. Khan: So, the coronary arteries are actually the arteries or pipelines that blood and oxygen to the heart muscle. They are not directly responsible for supplying the neck or the brain, they are just around the heart and they supply the muscle of the heart so that the heart can pump and basically supply blood to the vital organs of our body.
Bill: So, if it is totally occluded, wouldn’t that automatically mean an instant heart attack or does the body reroute blood to make it work? How does that happen?
Dr. Khan: Yes, so there are some patients who will have unrecognized heart attack and those are typically the ones where we find the blockage is chronic total occlusion and it’s probably been there for months or even years and those are typically the patients with silent heart attacks or they might have unrecognized symptoms like just general fatigue or shortness of breath which they will ignore. And there are collaterals, we call them collaterals which are helper channels that open up from the other vessels, other blood vessels try to compensate for this chronic total occlusion, but studies have shown that those helper channels are insufficient. They do not replace the adequacy of blood supply that is there from your natural – flow from the natural artery. So, collaterals are there. They might keep things under control a little bit, but when you are pushed, when you are – there is an increased demand on the heart muscle; then the collateral circulation is insufficient, and the patient might suffer bad chest pain or another small heart attack or shortness of breath and there is poor quality of life associated with people who have chronic total occlusion.
Bill: So, let’s talk about those symptoms a little bit more. So, you mentioned fatigue and shortness of breath. Are there any other symptoms we should be watching out for?
Dr. Khan: Yes, and there are obviously some patients who will have the typical chest pain mostly on exertion, described as a burning pain, tightness or pressure in the center of the chest and some patients might have dizziness, unexplained dizziness or even fainting spells frequently which are also sometimes serious. But the most common symptom that has been recognized is fatigue and shortness of breath.
Bill: So, how do you diagnose this then? When you go in for regular check-up of course, the doctor listens to your chest and you get an EKG, that’s not enough to diagnose this right? How do you find this?
Dr. Khan: Yes, so EKG is always a good place to start. EKGs will indicate is somebody has had an old heart attack and that might be the red flag that maybe he had old heart attack, it might be a chronically occluded old blockage in the heart. Then if the patient is not very symptomatic, then you can perform a stress test either a walking on the treadmill type of exercise stress test or one of the chemical stress tests to determine if there is an area which is chronically lacking blood supply. Following that, you can do the invasive testing which is the diagnostic coronary angiogram where you would insert a wire and a tube and towards the heart and squirt some dye into the heart and see if there is a blockage or not.
Bill: So, if there is a blockage then, how do you treat this?
Dr. Khan: So, that is the main thing – chronic total occlusion which blockage by definition means that it has been there for more than three months. They are not easy to treat. There is a very organized clot there. There is calcification, calcium making it very hard to crack open a hole in there to put in a stent, so oftentimes, the interventional cardiologist like myself, traditionally have left those blockages alone because it is difficult to open them. Historically the success rate is not very high and there are some increases of complications. But now we have some tools and some specialized wires with penetrating power to go through these blockages along with some tough balloons to crack open these blockages and then we have delivery mechanisms to go through the chronically occluded area and deliver these stents. It just takes longer. Oftentimes, we have even more than one cardiologist in the room to help each other out and a lot of patients. And for example, typically, a normal angiogram or a stent procedure might take 45 minutes to an hour. A chronically totally occluded blood vessel will typically take anywhere from one and a half to three hours.
Bill: So, you don’t want to stir that plaque up or break it up or all the sudden it starts travelling through other parts of the body. That’s a concern too. Is that right?
Dr. Khan: That is a concern. That is a concern and obviously we have – we give patients very high doses of blood thinners and we gently probe and break these blockages and we have some other unique methods for even going around the blockage and that’s a little bit more complex to explain in an interview like this. But we can even go around those blockages and come out on the other side of the blockage and create essentially a new channel within the vessel to do our own way of going around it. And that’s a very unique – we have some unique tools for doing that also. And me and my partner Dr. Mehta have started doing this in Bakersfield now and once a month, we line up patients who have been suffering with symptoms and have a chronically totally occluded blood vessel which has not been opened up and bring them into the hospital and we fix them and so far, we have seen very good results with almost 85-90% success rate in our practice.
Bill: Well that is really good news and I was just going to ask you that for someone treated for CTO, what is the long-term prognosis then?
Dr. Khan: Yes, the prognosis is really good. There are several studies now that have shown that there is an improved quality of life, increased exercise tolerance and certainly decreased angina or chest pain or shortness of breath type of symptoms in patients who have these blood vessels opened up. And there is also data of longevity that these patients live longer and there is a decreased risk of future heart attack. So, there is good evidence that in a suitable patient, they should be given a chance to have these old blockages opened up.
Bill: Well that is all really good news and Dr. Khan, thank you so much for talking with us about this today and for more information please visit dignityhealth.org/bakersfield/
Chronic Total Occlusion of Coronary Arteries and How to Treat It
Bill Klaproth (Host): Chronic total occlusion or CTO is a common heart disorder in many patients with coronary artery disease. So, what are the causes, how can you prevent this and what are the treatment options? Here to talk with us about chronic total occlusion of the coronary arteries is Dr. Nasser Khan, a cardiologist at Dignity Health. Dr. Khan, thank you for your time. So, what happens with chronic total occlusion of the coronary artery?
Nasser Khan, MD (Guest): Yes, thank you very much for giving me a chance to talk about this very important topic. Chronic total occlusion in the layman’s term means that there is 100% blockage in one of the main arteries of the heart which has been there for longer than three months. Previously, it has been a somewhat undiagnosed, undertreated and difficult to treat disease but now with improvement in techniques and some new tools in our hands, we are able to offer treatment for these lesions.
Bill: So, Dr. Khan, you just mentioned that this is underdiagnosed and undertreated, so potentially, many people suffer from chronic total occlusion of the coronary arteries. Is that right?
Dr. Khan: That is correct. So, in many studies, it has been shown that people who undergo angiograms routinely for either symptoms or no symptoms, who undergo angiograms, we have discovered that if a person has a 50% blockage in the heart in one of their arteries, there is a 25% chance that they have another blockage with is at least 100%. So, bottom line is, that the prevalence rate is anywhere from 20-25% in patients who have some blockage in their heart. They will also have 20-25% chance of having a 100% blockage also during the same angiogram.
Bill: That’s amazing. So, I’m thinking of the coronary artery in the neck going up to the brain, so you are saying that could be totally occluded, totally blocked?
Dr. Khan: So, the coronary arteries are actually the arteries or pipelines that blood and oxygen to the heart muscle. They are not directly responsible for supplying the neck or the brain, they are just around the heart and they supply the muscle of the heart so that the heart can pump and basically supply blood to the vital organs of our body.
Bill: So, if it is totally occluded, wouldn’t that automatically mean an instant heart attack or does the body reroute blood to make it work? How does that happen?
Dr. Khan: Yes, so there are some patients who will have unrecognized heart attack and those are typically the ones where we find the blockage is chronic total occlusion and it’s probably been there for months or even years and those are typically the patients with silent heart attacks or they might have unrecognized symptoms like just general fatigue or shortness of breath which they will ignore. And there are collaterals, we call them collaterals which are helper channels that open up from the other vessels, other blood vessels try to compensate for this chronic total occlusion, but studies have shown that those helper channels are insufficient. They do not replace the adequacy of blood supply that is there from your natural – flow from the natural artery. So, collaterals are there. They might keep things under control a little bit, but when you are pushed, when you are – there is an increased demand on the heart muscle; then the collateral circulation is insufficient, and the patient might suffer bad chest pain or another small heart attack or shortness of breath and there is poor quality of life associated with people who have chronic total occlusion.
Bill: So, let’s talk about those symptoms a little bit more. So, you mentioned fatigue and shortness of breath. Are there any other symptoms we should be watching out for?
Dr. Khan: Yes, and there are obviously some patients who will have the typical chest pain mostly on exertion, described as a burning pain, tightness or pressure in the center of the chest and some patients might have dizziness, unexplained dizziness or even fainting spells frequently which are also sometimes serious. But the most common symptom that has been recognized is fatigue and shortness of breath.
Bill: So, how do you diagnose this then? When you go in for regular check-up of course, the doctor listens to your chest and you get an EKG, that’s not enough to diagnose this right? How do you find this?
Dr. Khan: Yes, so EKG is always a good place to start. EKGs will indicate is somebody has had an old heart attack and that might be the red flag that maybe he had old heart attack, it might be a chronically occluded old blockage in the heart. Then if the patient is not very symptomatic, then you can perform a stress test either a walking on the treadmill type of exercise stress test or one of the chemical stress tests to determine if there is an area which is chronically lacking blood supply. Following that, you can do the invasive testing which is the diagnostic coronary angiogram where you would insert a wire and a tube and towards the heart and squirt some dye into the heart and see if there is a blockage or not.
Bill: So, if there is a blockage then, how do you treat this?
Dr. Khan: So, that is the main thing – chronic total occlusion which blockage by definition means that it has been there for more than three months. They are not easy to treat. There is a very organized clot there. There is calcification, calcium making it very hard to crack open a hole in there to put in a stent, so oftentimes, the interventional cardiologist like myself, traditionally have left those blockages alone because it is difficult to open them. Historically the success rate is not very high and there are some increases of complications. But now we have some tools and some specialized wires with penetrating power to go through these blockages along with some tough balloons to crack open these blockages and then we have delivery mechanisms to go through the chronically occluded area and deliver these stents. It just takes longer. Oftentimes, we have even more than one cardiologist in the room to help each other out and a lot of patients. And for example, typically, a normal angiogram or a stent procedure might take 45 minutes to an hour. A chronically totally occluded blood vessel will typically take anywhere from one and a half to three hours.
Bill: So, you don’t want to stir that plaque up or break it up or all the sudden it starts travelling through other parts of the body. That’s a concern too. Is that right?
Dr. Khan: That is a concern. That is a concern and obviously we have – we give patients very high doses of blood thinners and we gently probe and break these blockages and we have some other unique methods for even going around the blockage and that’s a little bit more complex to explain in an interview like this. But we can even go around those blockages and come out on the other side of the blockage and create essentially a new channel within the vessel to do our own way of going around it. And that’s a very unique – we have some unique tools for doing that also. And me and my partner Dr. Mehta have started doing this in Bakersfield now and once a month, we line up patients who have been suffering with symptoms and have a chronically totally occluded blood vessel which has not been opened up and bring them into the hospital and we fix them and so far, we have seen very good results with almost 85-90% success rate in our practice.
Bill: Well that is really good news and I was just going to ask you that for someone treated for CTO, what is the long-term prognosis then?
Dr. Khan: Yes, the prognosis is really good. There are several studies now that have shown that there is an improved quality of life, increased exercise tolerance and certainly decreased angina or chest pain or shortness of breath type of symptoms in patients who have these blood vessels opened up. And there is also data of longevity that these patients live longer and there is a decreased risk of future heart attack. So, there is good evidence that in a suitable patient, they should be given a chance to have these old blockages opened up.
Bill: Well that is all really good news and Dr. Khan, thank you so much for talking with us about this today and for more information please visit dignityhealth.org/bakersfield/