Upper Limb Arterial Doppler - Part 1

Introduction to Upper Limb Arterial Doppler

Hi, I'm Dr. Bul from Mumbai India.

I work at the tan ultrasound center and at the just hospital Mumbai and I'll be talking on upper limb arterial doppler.

Generally, when we talk of arterial doppler, we talk of lower limb arterial doppler.

Very rarely we talk of upper limb arterial doppler.

So what is so unusual about upper limb doppler?

Unusual Aspects of Upper Limb Arterial Disease

First of all, ischemia as far as ischemia is con, con is concerned.

Symptomatic arterial disease is less common in the upper limb as compared to the lower limb.

Res phenomena is a common presentation.

In lower limb we always think of atherosclerosis, whereas in upper limb we have to think of systemic disorders.

Ito arthritis is relatively a common occurrence in upper limb.

We have to think of thoracic outlet syndrome, subclavian, steel embolic episodes.

Another unusual thing about upper limb arties is that we have excellent collaterals around the shoulder, elbow, and wrist, and therefore very often these patients remain asymptomatic for quite some time.

Here's an example. This patient has a complete occlusion of the subclavian artery.

However, there is feeling through the internal mammary artery and if you look at the distal subclavian artery, it has got a very good lumen.

So this patient was asymptomatic for quite many months.

Another unusual thing about upper limb arteries is that trauma, especially vascular accidents, are more common in the upper limb as compared to the lower limb, and these accidents could be industrial or they could be electrification injuries.

Very often of course, upper limb arteries are used for dialysis grafts and fistulas, and we also do the Palmer arch patency test prior to a coronary artery bypass surgery.

Anatomy of Upper Limb Arteries

So just like any other examination, we have to be very familiar with the an anatomy.

For example, on the right side we have the denominate trunk, we have the common carotid, the vertebral artery, and of course the internal mammary artery, which is a very important branch of the denominate trunk.

Then of course we have the subclavian artery, the auxiliary artery, the brachial artery dividing into the radial alder and we have the superficial poage and the deep poage.

So one has to be very familiar with an anatomy. Anatomy before we start doing the examination.

Examination Protocol for Upper Limb Arterial Doppler

Whenever I do an upper limb arterial doppler, I always begin with the vertebral artery.

So typically the patient is lying down supine with the head extended and we look at a vertical artery adjacent to the carotid artery and make sure that there is a forward flow in the vertebral artery.

Then we look at the subclavian artery, which is just below this clavicle and we can trace the entire subclavian artery.

The normal subclavian artery shows a good flow, quick systolic up stroke, a downward flow, and almost aphasic flow, suggesting that this is a normal waveform.

Then we look at the auxiliary artery.

The auxiliary artery is typically examined by asking the patient to elevate the arm upwards and then going through the axi.

The brachial artery is evaluated by asking the patient to rotate the arm medially and we do a medial examination for the brachial artery in the upper arm.

Then both the forearm arteries are evaluated the radial artery and the other artery.

When we look at the radial artery, we always do the palmer arch pat it is.

So what we do here is while examining the radial artery, we compress the ular artery and look out for this elevation in the velocity.

Similarly, when we look at the ular artery, we compress the radial artery and look out for elevation in the velocity.

If there is an increase in velocity, it tells us that the Palmer arch is patent and that we can use these arteries for a bypass surgery.

This is a very important test.

When we look at the digital arteries, we like to use a higher frequency probe and generally we like to go along the lateral aspects of the digits because we know that digital arteries go along the lateral aspects.

Today with good machines, we are able to look at almost all digital arteries.

Normal Variations in Upper Limb Arteries

We can have normal variations and once such normal variation in the upper limbs is a brachiocephalic trunk ectasia.

This is more commonly seen in elderly females and we have a dilatation of brachiocephalic trunk and very often the patients are are symptomatic.

Raynaud's Phenomenon

One of the most common presenting feature in the upper limb is a renards syndrome and we have to understand renards syndrome.

Renards syndrome is is symptom complex, which is defined as an episodic.

Digital color changes occurring in response to emotional upset or environmental cold.

It's a presenting symptom in all patients with upper extremity ischemia results from a large variety of conditions wearing from exaggerated, but a benign vasos spastic response to cooling to severe and extensive arterial obstructive disease.

That means if the patient has a renar syndrome, it is just a symptom.

The cause of this symptom could either be an underlying arterial obstructive disease or the cause of this symptoms could be because of severe vasospasm with essentially normal arteries.

So when we look at upper limb ischemia, it is very important to differentiate between these two groups.

Differentiating Vasospasm from Arterial Obstruction

Vasospasm is usually seen in young females and they become symptomatic since early teens.

Both hands are usually affected and ulceration is very rare.

On the other hand, obstruction is seen in both males and females.

It is usually seen after 40 years and digital ischemic ulceration and gangrene is more common here.

So whenever we have a patient with upper limb ischemia, it is very important to distinguish large arteries from small arter disease and it is also very important to distinguish spasm from arterial obstruction.

Large Artery Obstructive Diseases

So one of the most common conditions which involves large arteries is thrombosis stenosis of the subclavian artery and thrombosis or stenosis of the subclavian artery very often present with subclavian steel or the vertebral steel.

So As an example of a thrombosis in the left subclavian artery with a vertebral steel happening on the same side with a reversal of flow in the vertebral artery as compared to the carotid artery.

Another example, this patient has a subclavian artery thrombosis in its proximal end and there's a reversal of flow in the vertebral artery.

The same patient has a stenosis in the left subclavian artery and that is what is known as a partial river steel in the right vertebral artery.

This partial steel waveform is very often referred to as a funny bunny waveform.

This patient, again has a subclavian artery thrombosis at the origin and there is a reversal of flow in the vertebral artery throughout telling us that there is a complete steel yet another patient now with a complete occlusion of the subclavian artery origin with the thrombus with a complete reversal of flow in the vertebral artery suggesting that there is a steel,

The subclavian artery may be affected not only at its origin but along its mid or distal portion, any a thrombus in the distal portion of the subcate artery, but the diagnosis comes up in the mid approximal portion of subcate artery.

What we see here is a quick systolic upstroke and multiple small peaks in the diastolic telling us that this is a high resistance flow and if you look at a distal waveform, there is a dampened waveform because of the thrombus in the distal subclavian artery.

Thoracic Outlet Compression Syndrome

Thoracic outlet.

Compression syndrome is another common thing we have to talk about in the upper limb arteries.

It's a complex of signs and symptoms caused by compression of vital neurovascular structures at the thoracic outlet region, pain, numbness, tingling, weakness, and other disorders in the upper extremity.

The compressed neurovascular structures in descending frequency include the brachial plexus, subin vein, and the artery compression usually occurs as a result of congenital or acquired changes in the surrounding fibro and fibromuscular structures.

Thoracic outlet syndrome is the most misunderstood, overlooked and misdiagnosed condition.

The thoracic outlet combination syndrome could potentially happen at three spaces.

One is the skully triangle, second is the OC clavicle space, and the third is a pectoralis minus space.

The etiological factors could be because of soft tissue lesions or boney lesions.

Soft tissue lesions include skully muscle hypertrophy, OID ligament injuries or compression because of OID ligament and at the level of the pectoral minor muscle.

The bony lesions could be a cervical rib, first rib abnormalities, long C seven transverse process or clavicle abnormalities.

So the symptoms in thoracic outlet could be neural or they could be vascular, or very often we have a combination of neural and vascular symptoms.

The neural symptom could be peripheral or they can be symptom symptomatic like re Bernard's phenomena.

Vascular symptoms could be because of arterial problems like loss of pulsations, claudications, or they could be because of venous involvement like pain edema, venous distension, collateral veins, or very often even thrombosis.

See the uh, the test which is commonly done for thoracic outlet syndrome is known as ENSs test.

The sys test is basically a clinical test which is performed by holding the patient's arm down and checking the radial pulse while the patient inhales deeply and keeps his head extended and turned towards the involvement extremity.

If the patient has a thoracic outlet syndrome, this action results in arbitration or decrease of the radial pulse.

As I said, this is a clinical test, but we can use it with doppler where we replace the hand, which is holding the pulse with an ultrasound probe.

We have another test which is known as neck tilting test.

This is similar to absences test.

However, here the patient tilts the head away from the affected side.

We have other tests like OG clavicle compression test where the examiner depresses the patient's shoulder or we have a hyper AB test where the patient is in a sitting position with the shoulders hyper abducted and rotated externally.

This is one of my favorite tests to look out for thoracic outlet syndrome.

We can modify this test by what is known as a rose test where we ask the patient to do exercises with the fingers.

So what do we see? This is a subclavian artery at rest showing a phasic waveform.

After an hyperabduction maneuver, we see that there is no flow happening in the subclavian artery, so this is a positive screening test for thoracic outlet syndrome.

Another patient on the left side, there is a good flow in the subclavian artery at rest.

After hyperabduction, we see that there is no flow in the subcate artery and if you look at the radial artery again, at rest we have got good flow, but after a hyperabduction maneuver, there is no flow in the radial artery suggesting that this patient has a thoracic outlet syndrome.

As I said, sometimes the veins can get affected.

This patient, for example, has normal flow in the artery subclavian artery, but if you look at the subclavian vein, at rest we have normal velocities, but after doing the maneuver, there is narrowing of the vein and this is shown on doppler as very high velocities, so veins can also get affected.

Some years back we did a study with one of my colleagues, Dr. Raju Ani, and published it in the general ultrasound and we found out that patients could have both arterial as well as venous involvement.

As I said, doppler is a screening test for thoracic outlet syndrome.

If you feel that a patient really has a thoracic outlet, then this has to be confirmed with more definitive tests like an angiography or a CT angiography.

And in CT angiography they very often do what is known as a langs manoa to find out if the patient has a thoracic outlet syndrome.

Takayasu Arteritis

The other condition which affects the upper limb and does not affect the lower limbs is aorta arthritis.

Aorta arthritis is an inflammatory disease of unknown etiology, which first affects larger artery of the body, especially branches of aorta.

It is described as aortic arch syndrome, pulseless disease reversed tation, occlusive thrombo arthropathy, young female arthritis or takasu arthritis.

Typically the arterial wall becomes markedly thickened and the lumen becomes narrow.

This is now commonly described as a Marconi sign.

Aorta is diagnosed by looking at certain clinical conditions, so we have what are known as obligatory criteria, major criteria and minor criteria.

This has now undergone modification and we no longer look at obligatory criteria, but there are modified major and minor criteria.

But what is very important is that subclavian arteries are almost always involved in aorta arthritis, and this is a major consideration here.

For example, we have a patient whose mid undistilled subclavian artery shows marked wall thickening and narrowing of the lumen with localized increase in velocity.

Another patient who has got a subclavian artery occlusion because of aorta arter and we can see a reversal of flow in the distal subc artery coming from a collateral.

So involvement of subcate artery is a very important finding in aorta arthritis and in our own study we saw almost involvement in 75% of the cases, but there are some studies which show involvement in almost 85 to a hundred percent of the cases.

Another diagnostic feature of a O2 arthritis is involvement of multiple arteries or multiple areas.

Here for example, we have a patient where the right arteries as well as left arteries of the upper arm are involved.

Other Large Artery Conditions: Thrombosis and Stenosis

Besides aorta, arthritis, we can have other common conditions which can affect larger arteries like thrombosis and stenosis.

This is a patient who has a left auxiliary artery thrombosis and again we can see few collaterals there.

This patient again has a thrombosis in the auxiliary artery, but if you look at the waveform in the subclavian artery, it's a very high resistance waveform telling us that there is some distal obstruction.

So we have a quick systolic up stroke and we have a downward diastolic flow with multiple peaks in the diastolic and rightly so.

The sub auxiliary artery shows a thrombosis.

There is a very good collateral there and distally.

We have dampen flow, which is very often referred to as a TARDIS parvis effect.

We can have auxiliary artery stenosis.

This patient has an auxiliary artery stenosis, we can see localized ing there.

Perivascular tissue vibration on color OBL with very high velocities happening under the site of stenosis.

This patient has a braque artery thrombosis ag.

Again, we can appreciate that there are a lot of collaterals around the brachial artery and if you look at the distal radi and an artery NAR arteries, we have a tardis S parvis effect.

This patient had upper ischemia.

There were a lot of digital changes.

However, this patient was asymptomatic for many months and years simply because there were extensive collaterals in the forearm.

So as I said earlier, very often there are very good collaterals in the upper arm and therefore the patient remain asymptomatic for quite some time.

This patient has an occlusion of the paricular artery and there is also an occlusion of the radial and as well as the other artery.

So sometimes the disease can be very extensive involving all the arteries of the upper arm.

If you look at this patient on colored oler, the auxiliary artery and the brachial artery look quite okay, but if you look at the waveform, it's a very hard resistance waveform.

There is a quick sharp systolic up stroke and there are multiple small peaks in the diastole.

This suggests that there is something happening distally and rightly so.

If you look at the forearm arteries, the forearm arteries, the radial as well as the ular are completely occluded beyond their, beyond the bra artery occlusion right up to the distal lens.

So it's very important to appreciate proximal waveforms to find out if something is happening distally and one can get clues to the proximal waveforms.

This patient has a complete occlusion of the older artery as well as on the digital arteries on the ulnar side.

Small Artery Diseases

So we talked of larger arterial obstructive lesions.

Let us come to the small arteries.

When we talk of small arteries, we are referring to arteries in the hand.

In these patients, typically the pulse and the pressure up to the elbow and the wrist is normal.

And whenever we think of small arterial disease, one has to think of a systemic disorder in the upper limb.

This is very important.

Atherosclerosis can affect the small arteries in the hand, but this is not so common.

On the other hand, systemic disorders are more common.

This patient has an occlusion of the dis mid and distal artery in the index finger.

This person was in fact a laparoscopies who worked a lot with the hand, and this was probably because of a professional injury.

So whenever we think of small arterial disease, as I said, we think of systemic disorders and very often they present with vasospasm a test to find out if the patient has an abnormal vasos.

Spastic response is known as cold stimulation test.

So what we do here is we look at the radial and the NAR artery at rest, then we ask the patient to hold highs in the hand and while the patient is holding eyes in the hand, we look at the waveform.

Typically, the patients are not able to hold the eyes for a long time and what we observe is a disappearance of the diastolic flow with UPS and diastolic flow or one can have a reversal of flow in the diastolic telling us that this there is a vasospasm, but this is a normal vasospastic response to eyes.

What happens in normal patients is that after they leave their eyes, the diastolic wave forms comes back to normal within a matter of three minutes or sometimes within a matter of five minutes.

Whereas a patient who has got an abnormal vasos spastic response or one who has got a positive cold stimulation test, the diastolic flow does not come back to normal even after some time.

Here's a very typical example.

Patient has a quick systolic up stroke, a very high resistance flow and an absent flow in the diastole, which remained for quite some time even after the patient had left the eyes.

This is a patient who has an SLE at rest.

We observe that there is a very high resistance flow in the radian a**l artery with a quick systolic up stroke, which is dampen and multiple small peaks in the diastole.

After doing a cold stimulation test, we see that the flow is further dampen.

The diastolic flow is almost absent and we have multiple small peaks in the diastole in this patient.

Even after releasing the eyes, the waveform did not come back to normal.

Sometimes the recovery time from a cold stimulation can be as much as 30 minutes, and this is a very good test to find out if the patient has an abnormal vasos spastic response.

Embolism in Upper Limb Arteries

The other common problem which can come up in upper limb and cause ischemia is embolism.

Embolism is more common in the upper limb as compared to lower limb and one of the most common sites of embolism is the heart, the mitral valve.

This is a patient who came with acute pain in the right upper arm and we can see that there is a source of embolism at the level of mitral valve.

Another patient who came with severe arm pain, one fine morning.

Again, we can see a fresh embolism in the auxiliary artery and the cause is again a vegetation at the level of the mitral valve.

Sometimes the embolism can affect the distal arteries.

This is a patient who came with pain and in the in the hand, and typically what we see is that the digital arteries, namely the ring finger arteries are occluded.

This can sometimes be difficult to evaluate, but if one is very careful with the digital arteries, we can come to this diagnosis.

Trauma and Other Causes of Upper Limb Ischemia

So as far as upper limb artery ischemia is concerned, it is very important to have an organized and systemic approach.

It is very important to find out if the patient has some underlying arterial disease or the patient has an abnormal vasos spastic response, and this is very important to plan the therapeutic procedure.

Trauma is very common in the upper limb and we have a variety of causes of trauma.

One of the most common cause of trauma is an industrial trauma.

This is a patient actually who came with an industrial trauma.

There's a large hematoma happening in the muscle and the brachial artery is totally occluded.

Another patient who came early in the morning with industrial trauma, we can see there's a lot of soft tissue laceration there and we can see a complete obstruction of the brachial artery involving the radial as well as the older artery.

This patient had quite an unusual AR agricultural trauma, so while he was working in the field and cutting the crops, one of the instrument happened to hit his elbow.

He had laceration in the brachial artery and we can see that there is no walls in the brachi artery and there's a huge thrombus there.

This patient had, again, a traumatic AV fistula and the liver of the AL elbow, and we can see that there's a communication between the brachial artery and the vein.

This patient again had traumatic AV fistula in the fingers.

Her hand accidentally went into a machine and we can be sure that this is an AV fistula.

By looking at the AAL vein, the AAL vein shows a pulsatile flow telling us that there is a communication between the artery and the vein.

This is yet another patient who was involved in a fight and after that he developed a swelling on the palm and we can see that there's a large vascular malformation on the palm.

If you look at the wave form, the arteries show a high diastolic flow and the veins show a pulsatile flow.

And if you look at these two wave forms, one can be sure that one is dealing with an ab fistula.

This was of course confirmed on a geography and that is the clinical picture of the same patient.

This patient had an injury with a stone and what we see is a localized dilatation of the distill radial artery because of a traumatic aneurysm.

As I said earlier, electrocution injuries are more common in the upper limb as compared to the lower limb.

This is a patient who was actually working with one of the electrical companies and during his job accidentally touched a wire.

He came to us with synosis and the entire forearm was black and color, and what we see is that the entire under artery and the radi artery were completely occluded.

This is a bad injury to happen to someone who is working.

Um, upper limb ischemia can also be because of hydrogen injuries.

This is a story of an eight day old baby who came to us for upper limb dola.

This child was born premature and had a tough time in the first two days of life.

The child presented to us after eight days with the pulses not being felt.

So what we observe here is that there is a thrombosis of the entire venous system, and if you look at arteries, there's flow in the brachial artery in the proximal radial and ular artery.

However, there is no flow distally.

If you look at the waveforms, there is a high resistance waveform in the subclavian artery and the brachial artery, but the brachial artery beyond the bifurcation, the vessels do not show any flow in the radial and artery.

So it's very important to look at proximal artery of wave form to diagnose something which is happening distally.

This is another patient who used to work a lot with some machines and came with his chiia in the hand, and what we see is a soft tissue thrombus involving the distal radial artery.

This was adequately treated.

Of course One can have compartment syndrome in the upper limb.

This patient, again, had history of trauma, then came with soft tissue edema, and as we know that in a compartment syndrome there's a lot of soft tissue edema and therefore there is increased resistance to the blood flow.

And one of the diagnostic criteria of a compartment syndrome is a pan reversal of flow in the diastole.

So if you look at the brachial artery, the radial and the other artery proximal portions, we see that there's a reversal flow happening throughout the diastole and this is diagnostic of a compartment syndrome.

Palmar Arch Patency for Bypass Surgery

Upper limb arteries are also used for a bypass surgery, typically in a coronary bypass surgery.

But before anyone lifts up the radial or the al artery, one has to be very sure that the Palmer arches patent and the test for this is known as Alan's test.

So typically what we do is we look at the radial artery, compress the ler, look at the ulnar, compress the radial, and look out for elevation and velocity.

As we have already described.

If there is no increase in velocity as is seen in this case, that means the palm arch is not patent, the arteries are affected, and lifting up the radial or the ular artery in this patient would not be a right thing to do.

Conclusion

So overall, as far as hische is concerned, it's very important to differentiate between large arteries and small arteries.

It is very important to differentiate between obstructive lesions and vasos spastic uh uh, abnormal vaso spastic response.

As we said, trauma is very common, and of course upper Aries are used for access grafts, which is a different topic altogether, and it is also important to look at the palmach patency.

Thank you so much.