Brief Answer:
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Detailed Answer:
I read your question carefully and I understand your concern.

Ischemic stroke means a blockage of a blood vessel in the brain circulation. As a result an area of the brain does not get blood supply and is damaged. Depending on whether it is a large blood vessel or a small one as well as the precise area involved, it can leave from invalidating damage (even death) to minor damage which is well compensated in time by the brain. Luckily for you it was the minor case.

Now the current stroke has gone, you've already seen the worst of it. However that doesn't exclude another blood vessel being affected in the future, another stroke in a different area.

For that reason it is necessary to search for the origin of this first stroke in order to take measures to prevent it from happening again.

Most common causes are atherosclerosis of the occluded vessel or emboli (traveling blood clots) coming from elsewhere in the circulation which could be from the heart or clots formed on atherosclerotic plaques in the big main arteries. There is also venous thrombosis similar to the DVT but in the brain.

So a battery of tests when in hospital is necessary like head imaging (CT or preferably MRI), Doppler ultrasound of neck and brain vessels, heart ultrasound and EKG. When these reveal nothing abnormal it is often pushed further with transesophageal ecocardiography or prolonged Holter EKG. Some routine blood tests are done as well such as blood count, glucose, lipid panel, electrolytes, liver and kidney function tests, some coagulation tests. Perhaps you've done most of that already, your primary physician should check the documentation.

Looking at your medical history you have already some risk factors. You have a history of thrombosis predisposition, DVT and PE so it should be looked in the heart for a foramen ovale, a hole between your heart chambers (20% of people have it) which in case of thrombi in the veins could allow traveling thrombi to enter the left side of the heart and the arterial circulation and go to the brain. So if that is the case it can be closed surgically to prevent it from happening again.
You also have polycythemia which increases blood viscosity and increases risk for thrombosis.
There is also diabetes which favours formation of atherosclerotic plaques.

So to answer your questions:

Is there anything in particular that absolutely should be followed through with? - it should absolutely be searched for the origin in order to choose the best strategy of prevention for the future. The best strategy could be the current one with Aspirin and Plavix, diabetes and hypertension treatment, could be anticoagulants or in some cases even surgical procedures.

Is there anything that will happen if certain procedures are not done? - there is the risk of a another stroke in the future. The risk will always be there considering your many conditions and predisposition for blood vessel problems, the question is to lower it as much as possible.

I remain at your disposal for further questions

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Brief Answer:
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Detailed Answer:
Thank you for the feedback and the additional info.

If we are referring to the stroke then the specialist to evaluate it is a neurologist, depending on where you live and availability it would be preferable to be a neurologist with vascular neurology as a subspecialty (if not available a general neurologist), he can review all the tests and decide on the most probable cause and the best prevention.

That doesn't necessarily mean the need for other specialists is excluded. Considering the different conditions you have, hematologist or endocrinologist periodic consults are needed for the myeloproliferative condition and diabetes.

If I were to judge from what you refer (but I repeat all the tests reports are needed to make a complete picture), I believe that for at least part of your problems the primary cause may already be known. The myeloproliferative condition can be at the root or at least play a part in your history of portal vein thrombosis, DVT, PE as well as the recent stroke it predisposes to all of them and is the most probable cause. They are all thrombotic occlusions of blood vessels, it is a similar process only manifesting in different sites. Unfortunately since it is a genetic condition it can not be completely removed, only its consequences be mitigated, lower the risk of such thrombotic complications. The best medication for that you are already taking aspirin and plavix.

As for surgical procedures if the narrowing caused by plaques is less than 50% it is not intervened surgically, only above 70% is there clear benefit. As for other possible procedures (rarely done) such as foramen ovale closure or vena cava filter that depends on the type of thrombosis and the rest of the imaging results.

I hope to have been of help.

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Brief Answer:
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Detailed Answer:
Hello again and thank you for the appreciative words.

An endocrinologist is a medical doctor specialized in conditions related to hormonal imbalances, diabetes is such a condition, so an endocrinologist is the most specialized in that condition. I do not mean to say that your internist is not doing that well, diabetes is a very very common disease, often affecting other internal organs, so an internist has also a lot of expertise in dealing with it. I suggested an endocrinologist as you mentioned a specialist other then primary physician, but a good internal medicine specialist can follow diabetes just fine.

As for something to definitely stop the risk, I am sorry but there is no such a permanent solution, there will always be some risk in the background. As it is a genetic condition it can't be cured, only control it and its complications be reduced. For that the means at our disposal are phlebotomy and the antiaggregants (aspirin and plavix). There is also hydroxyurea, but I think I saw you mention in some past question that you didn't tolerate that.

I hope these measures will be enough to prevent further episodes.

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Brief Answer:
You're welcome.

Detailed Answer:
I hope things work out for the best.

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