Vascular Lab

What Is a Vascular Lab?

A vascular laboratory is a specialised diagnostic facility used to examine arteries and veins without routinely requiring an invasive procedure. The investigations use technologies such as vascular ultrasound, Doppler assessment, pressure measurements and pulse-volume recordings to study blood flow and circulation. This is different from a general ultrasound scan. In a vascular study, we are often trying to answer a specific circulation question.

For example:

1. Is there a blood clot in this swollen leg?
2. Are the arteries supplying this foot narrowed?
3. Why is this diabetic wound not healing?
4. Which veins are leaking in a patient with varicose veins?
5. Is this bypass graft continuing to function properly?
6. Which vein may be suitable when planning vascular access?

The useful test is the one that answers the patient’s clinical problem.

Why I Use a Vascular Lab Before Planning Treatment

One thing I repeatedly explain to patients is that vascular treatment should not start with the procedure. It should start with the diagnosis. If somebody comes with leg pain, I first need to understand whether the problem is coming from an artery, vein, nerve, joint or another cause. If somebody has swelling, I need to distinguish possible DVT from chronic venous disease and other causes of leg swelling. If a diabetic patient has a wound, I need to know whether poor arterial blood supply is contributing to delayed healing.
And before treating varicose veins, I need to understand the reflux pattern underneath the skin. The vascular lab gives us objective information that helps make these decisions. Sometimes the test confirms an important vascular problem. Sometimes it shows that the circulation is reasonably preserved. Both results are useful because the purpose of testing is not to find a reason to perform a procedure. The purpose is to understand the circulation properly.

Which Vascular Test Might I Need?

Different symptoms require different vascular investigations.

This is a guide, not a test-ordering checklist. One symptom can have several causes. The correct investigation should follow the clinical assessment.

Arterial Testing for Poor Blood Circulation

1. Arteries carry blood from the heart towards the legs, arms and organs.
2. When an artery becomes significantly narrowed or blocked, the tissue beyond that point may receive less blood.
3. The symptoms depend on how severe the circulation problem is.
4. Some patients develop pain in the calf or thigh while walking.
5. Others notice that one foot feels colder.
6. More advanced arterial disease can cause pain even at rest, non-healing wounds or tissue loss.

Our vascular lab assessment for arterial disease can include physiological circulation testing and arterial duplex ultrasound depending on the clinical problem.

What Is an ABI Test?

ABI stands for ankle-brachial index. It compares the blood pressure measured at the ankle with the pressure measured in the arm. The test helps us understand whether the pressure reaching the lower limb is reduced. ABI is useful when assessing patients with symptoms that may suggest peripheral arterial disease. But I do not interpret an ABI number alone. A patient with diabetes or kidney disease may have stiff, calcified arteries that can make pressure measurements more difficult to interpret. The value therefore needs to be considered together with the patient’s symptoms, pulse examination and other vascular findings.

If arterial disease is suspected, you can read more about the complete treatment pathway on the Peripheral Arterial Disease page.

Segmental Pressure and Pulse Volume Recording

Sometimes we need more information than a single pressure measurement. Segmental pressure assessment looks at blood-pressure changes at different levels of the limb. Pulse volume recording, or PVR, evaluates changes in blood volume within the limb with each heartbeat and produces characteristic waveforms. These tests can help us understand whether arterial circulation is reduced and give information about the level at which disease may be present. They are non-invasive physiological tests and can complement vascular ultrasound.

Exercise or Treadmill Testing for Walking Pain

Some patients have a very specific complaint: “Doctor, when I am sitting I am fine. After I walk for a few minutes, my calf starts hurting.” In selected patients, circulation may appear less abnormal at rest but symptoms become evident with exercise. Exercise or treadmill assessment can therefore be useful when we need to relate walking symptoms to arterial circulation. Again, the test should answer a clinical question. Not everybody with leg pain needs a treadmill vascular study.

What Is an Arterial Duplex Ultrasound?

Arterial duplex ultrasound allows us to see the artery and assess how blood is flowing through it. The study can help identify areas where blood flow has become abnormal because of narrowing or blockage. It can also be useful in selected patients who have undergone previous arterial treatment. One important point is that an ultrasound report showing stenosis does not automatically mean the patient needs angioplasty.

I ask:

• How severe is the circulation problem?
• Does it explain the symptoms?
• Is the limb at risk?
• Would restoring blood flow offer a meaningful benefit?

The scan guides the decision. It does not make the decision by itself.

Venous Testing for DVT

A vascular lab also plays an important role in evaluating venous disease. One of the most important situations is suspected deep vein thrombosis.

A patient may come with:

• sudden swelling in one leg
• calf or thigh discomfort
• heaviness
• warmth
• a change in skin colour
• symptoms following surgery, prolonged immobility or another DVT risk factor

Venous duplex ultrasound allows us to examine the deep veins and look for thrombosis. The examination can assess both upper and lower limbs depending on the clinical concern. If DVT is confirmed, the next step is not simply to say:

“There is a clot.”

We need to know where the clot is, how extensive it is, the patient’s clinical condition and what treatment is appropriate. Most DVT patients are treated primarily with anticoagulation, while selected extensive cases may need further vascular assessment. Read more about Deep Vein Thrombosis and deep vein treatment.

When suspected DVT becomes an emergency

If leg swelling is accompanied by sudden breathlessness, chest pain, coughing blood, fainting or severe difficulty breathing, seek emergency medical assessment. Do not wait to schedule a routine vascular-lab appointment.

Venous Duplex for Varicose Veins

Visible varicose veins are only the part of the venous problem that we can see from outside. Before planning treatment, I want to understand what the veins underneath are doing. A venous duplex study can assess:

• superficial veins
• deep veins
• valve function
• direction of blood flow
• areas of venous reflux
• previous thrombosis where relevant

This helps us map the actual source of venous pressure. Two people may have similar-looking varicose veins but very different reflux patterns. Their treatment should not automatically be the same. You can read more about the treatment pathway on the Varicose Veins and Venous Disorders page.

Chronic Venous Disease and Leg Swelling

Not every swollen leg has DVT. Long-standing swelling may be associated with chronic venous insufficiency, previous DVT, lymphatic problems or non-vascular medical conditions. Patients with chronic venous disease may also develop:

• leg heaviness
• ankle swelling
• skin pigmentation
• itching or eczema-like changes
• hardening of the tissues
• venous ulcers

Venous ultrasound helps us understand whether reflux or obstruction is contributing to the problem. This matters because treatment for acute DVT is very different from treatment for chronic venous reflux. The symptom may be “leg swelling” in both cases. The diagnosis is not the same.

Vascular Testing for a Diabetic Foot Wound

A diabetic foot wound is one situation where I do not want circulation to be overlooked. A patient may be receiving regular dressing and antibiotics, but the wound continues to remain open. There can be several reasons:

• infection
• neuropathy
• repeated pressure
• poor glucose control
• inadequate arterial blood supply

The vascular lab helps us assess the circulation component of that problem. If blood supply is significantly reduced, the wound may struggle to heal until the arterial problem is addressed. But a diabetic foot wound does not automatically mean the patient needs angioplasty. We first determine whether circulation is actually inadequate and how much it is contributing to the wound. You can read more about this approach on the Diabetic Foot Care page.

Vein Mapping Before Bypass Surgery

When bypass surgery is being considered, the patient’s own vein may sometimes be used as part of the bypass. Vein mapping uses ultrasound to examine suitable veins before surgery. It helps us understand:

• where the vein runs
• its approximate size
• whether it is open
• whether it may be suitable for the planned operation

Planning this before surgery helps the vascular surgeon understand the available conduit options.

Vein Mapping for Dialysis Access

Vein mapping can also be useful when planning an AV fistula. Before creating dialysis access, I want to know whether the arteries and veins are suitable and which access site makes sense for the patient’s long-term dialysis plan. This is especially important because veins should be treated as a long-term resource in patients who may require haemodialysis. You can read more about fistula planning on the Dialysis Access Surgery page.

Bypass Graft Surveillance

A bypass procedure restores circulation by providing another route for blood to travel around a blocked arterial segment. But treatment does not end when the surgery is completed. Selected bypass grafts require follow-up. Duplex surveillance can help assess blood flow through the graft and look for changes that may require closer monitoring or treatment. The purpose of surveillance is to identify a relevant problem before it presents as complete graft failure where possible. The follow-up schedule depends on the operation, graft and individual patient’s vascular condition.

Aneurysm Screening and Surveillance

An aneurysm is an abnormal enlargement of an artery. Our vascular lab provides ultrasound assessment for appropriate aneurysmal disease, including screening and follow-up surveillance of the abdominal aorta and selected peripheral vessels. Ultrasound is particularly useful for monitoring aneurysm size over time when surveillance has been recommended. Not every aneurysm needs immediate treatment. The decision depends on factors such as:

• size
• location
• rate of change
• symptoms
• anatomy
• individual patient factors

A vascular scan allows us to monitor the condition objectively. Sudden severe abdominal, back or chest pain in somebody with a known or suspected aneurysm should not wait for a routine surveillance scan. It needs urgent medical evaluation.

Carotid and Cerebrovascular Vascular Testing

The vascular lab also performs appropriate imaging of carotid and vertebral circulation, with transcranial assessment where clinically indicated. These studies evaluate blood vessels involved in supplying blood to the brain. The need for testing depends on the patient’s symptoms, clinical history and the specific question being investigated. A scan should not be used as a substitute for emergency stroke assessment. Sudden facial weakness, arm weakness, speech difficulty, loss of vision or another possible stroke symptom requires urgent emergency care.

What Is the Difference Between the Vascular Lab and a Doppler Scan?

This distinction is important because we now have a dedicated Doppler service page as well.
A vascular Doppler scan is one investigation.

The vascular lab is the broader diagnostic service.

The vascular lab brings together different types of arterial, venous and physiological testing. Depending on the problem, the assessment may involve:

• duplex ultrasound
• Doppler blood-flow assessment
• ABI
• segmental pressure testing
• pulse volume recording
• exercise testing
• vein mapping
• surveillance studies

So if you have specifically been advised an arterial or venous Doppler scan, the dedicated vascular Doppler service page explains that examination in detail. If you are not yet sure which vascular test you need, the vascular lab page is the better starting point.

Does Vascular Lab Testing Use Radiation?

Most vascular-lab investigations described on this page are non-invasive and do not use ionising radiation. Ultrasound uses sound waves to create images and assess blood flow. Pressure measurements and pulse-volume recordings are physiological tests performed from outside the body. This makes the vascular lab useful for initial diagnosis as well as repeated surveillance when clinically required. CT angiography and catheter angiography are different investigations and are not the same as non-invasive vascular-lab testing.

Is Vascular Lab Testing Painful?

Most vascular-lab investigations do not involve an incision. For ultrasound studies, gel is placed on the skin and a probe is moved over the area being examined. During a DVT study, pressure may be applied with the probe to assess whether the vein compresses normally. Blood-pressure cuffs are used during physiological arterial studies. If an area is already very painful, swollen or inflamed, parts of the examination may cause temporary discomfort. Tell the vascular physiologist if something is particularly painful during testing.

Do I Need to Prepare for a Vascular Lab Test?

Preparation depends on the test. For many lower-limb arterial and venous studies, extensive preparation is not required. It is useful to:

• wear comfortable clothing
• bring your referral if another doctor requested the test
• carry previous vascular reports and scans
• bring a current medication list
• mention any previous angioplasty, bypass, DVT or vascular surgery

Do not stop prescribed medicines unless your treating doctor has specifically advised you to do so. Some abdominal vascular studies may require different preparation, so follow the instructions given when the investigation is scheduled.

Who Performs the Tests in the Vascular Lab?

The vascular lab has a team of five trained vascular physiologists who perform non-invasive vascular assessments using appropriate vascular-laboratory protocols. The technical quality of the test matters. But equally important is what happens after the measurements are taken. I relate the findings to the patient’s symptoms, examination and overall vascular problem. That distinction is important because a technically abnormal finding does not always require intervention. The value of the vascular lab is not just generating a report. It is giving us information that can be used to make a better clinical decision.

What Happens After the Test?

The next step depends on the finding.

If the test is reassuring

No vascular procedure may be required. The symptoms may need evaluation for another cause, or the vascular problem may simply need follow-up.

If arterial disease is found

We decide whether medical treatment, exercise, wound care, further imaging or revascularisation is appropriate.

If DVT is found

Anticoagulation and further management are planned according to the location and clinical circumstances.

If venous reflux is found

The reflux pattern is related to symptoms before discussing treatment for varicose veins or chronic venous disease.

If a diabetic foot has poor circulation

We combine the circulation findings with wound, infection and tissue assessment to decide whether blood flow needs to be restored.

If surveillance identifies a new problem

Further imaging or treatment may be considered according to the individual finding.

An abnormal vascular test does not automatically mean surgery.

It means we now have better information to make the next decision.

When Does the Cath Lab Become Relevant?

The vascular lab and cath lab have different roles.

The vascular lab diagnoses and monitors circulation using non-invasive tests.

The cath lab is used for selected catheter-based imaging and endovascular treatment when a patient actually needs it.

For example, if arterial testing shows significant poor circulation in a patient with rest pain or a non-healing wound, additional imaging may be required before planning angioplasty. If a dialysis access has a clinically important stenosis, catheter-based treatment may sometimes be considered. The sequence should remain logical:

• Clinical assessment
• Appropriate non-invasive vascular testing
• Treatment decision
• Further imaging or endovascular treatment only when required

I do not want the patient to think that coming to the vascular lab automatically means they are heading for an angioplasty. Often, the vascular lab helps us avoid unnecessary invasive testing as much as it helps identify patients who genuinely need further treatment.

Vascular Lab in Basavanagudi, Bangalore

Dr Sravan’s vascular practice and vascular laboratory are based in Basavanagudi, Bangalore. Patients are evaluated for arterial and venous circulation problems including:

• peripheral arterial disease
• DVT
• varicose veins
• chronic venous disease
• diabetic foot circulation
• aneurysm surveillance
• dialysis-access planning
• vein mapping
• follow-up after selected vascular procedures

For patients from Basavanagudi and surrounding parts of South Bangalore, the vascular lab provides a direct pathway from vascular assessment to the appropriate investigation and, where required, specialist treatment planning.

When Should You See a Vascular Surgeon?

Vascular assessment may be useful if you have:

• calf pain that repeatedly starts while walking
• a cold foot or weak foot pulse
• sudden swelling in one leg
• suspected or confirmed DVT
• visible varicose veins with pain or swelling
• skin darkening near the ankle
• a venous leg ulcer
• a diabetic foot wound that is not healing
• toe discolouration or gangrene
• an AV fistula or dialysis-access problem
• a known aneurysm requiring surveillance
• an abnormal vascular scan that you do not understand
• a recommendation for angioplasty, bypass or another vascular procedure and need clarification

Sudden severe limb pain associated with a pale, cold, numb or weak limb requires urgent evaluation. Possible stroke symptoms, severe breathing difficulty with suspected DVT, or severe symptoms associated with an aneurysm should also be treated as emergencies rather than routine vascular-lab appointments.

How I Use the Vascular Lab in My Practice

Many patients come to me carrying a report and ask:

“Doctor, is this serious?” That is understandable. Medical reports contain words such as stenosis, reflux, occlusion, thrombosis and reduced flow, but those words mean very little to a patient without context. I use the vascular lab to answer the clinical question first. If you have walking pain, I want to know whether circulation is causing it. If one leg is swollen, I want to know whether there is a clot or another venous problem. If you have varicose veins, I want to know where the reflux is coming from. If a diabetic wound is not healing, I want to know whether enough blood is reaching the foot. And if you have already undergone vascular treatment, I want to know whether the treated circulation is functioning as expected. A good vascular test should give clarity, not simply another report. That is how I prefer to use the vascular lab. Dr Sravan C.P.S is a vascular and endovascular surgeon in Bangalore. His qualifications include MBBS, MS in General Surgery, MRCS from the Royal College of Edinburgh, DNB in Peripheral Vascular Surgery and FEVS from National University Hospital, Singapore. His practice includes arterial disease, venous disorders, diabetic foot circulation, dialysis access, aortic disease and endovascular treatment where appropriate.

FAQs

What tests are done in a vascular lab?

A vascular lab performs non-invasive tests used to assess arteries and veins. Depending on the clinical problem, these may include arterial and venous duplex ultrasound, ABI, segmental pressure and pulse-volume studies, exercise testing, vein mapping and vascular surveillance examinations.

What is the difference between a vascular lab and a Doppler scan?

A Doppler scan is one type of vascular investigation. A vascular lab provides a broader range of arterial, venous and physiological tests. The correct test is selected according to the circulation problem being investigated.

Can a vascular lab detect blocked leg arteries?

Arterial duplex, ABI and other physiological circulation tests can help identify evidence of peripheral arterial disease and determine whether blood flow to the leg is reduced. Further imaging may be required when an intervention is being planned.

Can a vascular lab test for DVT?

Yes. Venous duplex ultrasound is used to assess the deep veins when DVT is suspected. If DVT is confirmed, treatment depends on the location and extent of the clot and the patient’s clinical situation.

Do I need a Doppler before varicose vein treatment?

Venous duplex assessment is important when planning treatment for symptomatic varicose veins because it identifies the pattern of reflux and evaluates the superficial and deep venous systems.

Does vascular testing require an injection or radiation?

Most investigations performed in the vascular lab are non-invasive. Standard vascular ultrasound uses sound waves rather than ionising radiation, while ABI and pressure-based tests are performed externally. More detailed imaging such as CT angiography or catheter angiography is a separate investigation.

What happens if my vascular test is abnormal?

Dr Sravan relates the result to your symptoms and clinical examination. Depending on the finding, the next step may be observation, medical treatment, compression, wound care, further imaging or a vascular procedure. An abnormal report does not automatically mean an operation is required.

Book a Vascular Lab Assessment in Bangalore

If you have leg pain while walking, unexplained swelling, varicose veins, a diabetic foot wound, suspected poor circulation, DVT concerns or a vascular condition that needs surveillance, you can consult Dr Sravan C.P.S for vascular assessment and appropriate testing in Bangalore. The purpose of the vascular lab is to answer three questions:

• What is happening to the circulation?
• How important is the finding?
• What should we do next?

Sometimes the answer is treatment. Sometimes it is follow-up. And sometimes the most useful result is knowing that an invasive procedure is not required.

Book an appointment for vascular evaluation and vascular lab testing with Dr Sravan C.P.S.