Fortis Hospital, Kolkata
You had a very interesting talk on vitamin K antagonist. Old is gold. So do you still believe that old is gold in this case?
Definitely it is. Because it has served us for more than 16 years now and definitely it has its own problems, but it does have so many patients and so many doctors with their problems. So definitely we have an option which serves at least for next 20 to 30 years, we are not sure whether the newer ones are the better than the old so. Still old is gold.
Still and especially in the country like ours, the cost remains the major issue.
So newer ones are appropriately very costlier.
One problem with the newer agents is that they are very costly and they are not approved for all the indications. You see one of the major problems in this country is that valvular atrial fibrillation and the definition of valvular atrial fibrillation is still not very clear.Because with the huge burden of rheumatic valvular heart disease, mitral stenosis is the definite contraindication for newer OACs and even with severe aortic valve disease or severe mitral regurgitation we are not sure whether NOAC is the newer anticoagulants are suitable for them or not and prosthetic valves are strict no on newer oral anticoagulants. So these events have big area where still vitamin K antagonists are the only options and still old is gold.
And I think the reversal is also possible we have.
Yeah, reversal is another problem which is said to an advantage for NOACs is the absence of monitoring. But you see monitoring can sometimes be a desired option. Because when you are not sure with the patient's compliance you may not know that whether the patient is taking it regularly or not more so because two of them like to take twice a day. So if the patient forgets one dose, there can be a rebound thrombogenicity. So that is the problem. Another problem of course is vitamin K antagonists are easily reversible with simple injection called vitamin K and of course there are other options with newer anticoagulants, we do not have any antidotes that are available in the market.
So what is your comment on that newer available agents. How do you compare them as they all same or do they defer with each other?
Yeah, has definitely difference as sub groups, dabigatran is the direct thrombin inhibitor and rivaroxaban and apixaban and edoxaban, these are direct factor thrombin inhibitors. So there is segregation there and in terms of side effects also. Dabigatran has been implicated with slightly higher incidence of GI bleeds and higher incidence of myocardial infarction. Apixaban from that point of view is said to have a lower incidence of bleeding probably safer. So in a patient who is slightly older with low body weight and more than 80 years old if we have to use NOACs, I personally will be more than frankly use apixaban, but left it still quite premature to say whether it is safe and they were not because of our experience is still in the evolvin phase. So rivaroxaban frankly speaking I do not have any experience.
If cost is not a barrier, will you still go with vitamin K antagonist or you will like to use newer agents?
As I said, indications should give a #1 priority where I am using it. If the indication says yes, you can use NOACs, if I think that the patient can afford it, if I can rely on his compliance, then of course I will consider NOACs. Because monitoring ingredients has its advantages but disadvantages are too many and with lack of standard level to reaching the peripheries or the smaller cities it can indeed be a problem.
How high is the risk of bleeding once we compare these agents?
As I said, I mean every one tends to underestimate the newer OACs in terms of bleeding but bleeding does occur even with newer OACs and once you have bleeding, it is a problem because you cannot reverse it easily. On the other hand definitely bleeding is a problem with vitamin K antagonist, we have known of cerebral bleeds which occur even with an acceptable INR on the same time once there is a problem with INR maintenance, it is not in the therapeutic range, especially with prosthetic valves, we have valves, so we have problems at both end of the spectrum, once with high thrombogenicity or with excess of bleeding. So it is indeed a problem. So managing anticoagulation takes a lot of skill, lot of experience and lot of trust between the patient and the doctor.
So I think the messages we need to clearly choose the agent based on the patient's parameters, based on the affordability of the patient and the clinician's experience with the molecules.
Yes. Of course.
So thanks sir. Thanks a lot for joining us and sharing your views on the topic. Thanks a lot.