Diabetes and Your Heart

Diabetes can affect your heart even when you feel well. Over time, it can damage the blood vessels that supply the heart and increase the chance of a heart attack. It can also affect how the heart fills and pumps.

That does not mean heart disease is inevitable. Looking after your sugar, blood pressure and cholesterol, and choosing medicines that suit your health, can help protect your heart. Knowing which symptoms to act on matters too.

Dr. Kulin Sheth is an interventional cardiologist in Ahmedabad, consulting at Sheth Heart Clinic in Bopal. He looks after people with diabetes who have heart concerns or an existing heart condition, working with your primary diabetes care provider or endocrinologist to manage your heart health and diabetes together.

It can damage the arteries supplying the heart

High blood sugar over time can damage the lining of blood vessels. Diabetes also commonly occurs alongside high blood pressure and cholesterol problems, which add to that damage. Fatty deposits, called plaque, can build up in the arteries that supply the heart muscle. This is coronary artery disease.

As an artery narrows, the heart may not get enough blood during activity. You might notice chest discomfort or breathlessness when walking. If a plaque ruptures and a blood clot blocks the artery, it can cause a heart attack.

It can affect heart function, even without a heart attack

Diabetes also increases the risk of heart failure. The heart may become less able to relax and fill, or its pumping may weaken. This can happen without a previous heart attack and sometimes without a major coronary blockage.

Despite the name, heart failure does not mean the heart has stopped. It means the heart is having difficulty doing its job. Breathlessness, swollen ankles or a fall in your usual stamina can be signs. Other conditions can cause these symptoms too, so they need to be assessed rather than attributed to diabetes alone.

Symptoms may be less obvious

Diabetes can damage nerves, including those involved in how you feel pain. Some people therefore have less chest pain than expected, or a heart attack that goes unrecognised at the time. You may hear this called a silent heart attack. Others do have typical chest pain. The absence of pain is not enough to tell whether your heart is healthy.

“Meri sugar toh control mein hai. Phir heart ka risk kyun?”

Good sugar control helps, but it cannot remove every reason for heart disease. Your HbA1c shows your average glucose over recent months. It does not tell us how much plaque is in your arteries or how well your heart pumps.

How long you have had diabetes, blood pressure, cholesterol, tobacco use and family history also matter. Kidney disease deserves particular attention because it can increase heart risk and influence which medicines are suitable.

This is why your heart review may lead to a change in blood-pressure or cholesterol treatment even when your sugar report looks good. We need to look at these together. If your sugar has been difficult to control, improving it is still worthwhile; you have not missed your chance to benefit from treatment.

A change in what you can comfortably do is worth mentioning. You may be stopping on stairs you used to climb easily, feeling breathless on your usual walk or noticing chest discomfort with activity. Unusual tiredness, swollen ankles or trouble breathing when you lie flat should also be checked.

A heart attack does not always cause severe chest pain. Some people with diabetes have milder or less familiar symptoms. Do not assume new discomfort is “gas” because it is mild, or because your sugar reading is normal.

Seek emergency care immediately for possible heart-attack symptoms: chest pressure or discomfort, pain spreading to the arm, jaw or back, sudden breathlessness, cold sweating, nausea or faintness, particularly when symptoms occur together. Sudden severe breathlessness or collapse also requires emergency help. Call an ambulance or local emergency service; do not drive yourself or wait for a clinic appointment or WhatsApp reply.

Our guidance on chest pain and heart-attack symptoms explains when to seek urgent help.

Along with your sugar, we need to look after your blood pressure, cholesterol and kidneys. Avoiding tobacco, keeping active at a level that is safe for you, and making manageable changes to food and weight all help.

You may be prescribed a statin even if your cholesterol report does not look very high. The reason is your chance of developing heart disease, not just one blood-test result. Aspirin needs a separate discussion. It can cause bleeding and is not automatically needed by everyone with diabetes.

Yes. Some medicines used for type 2 diabetes can help protect the heart or kidneys as well as lower sugar.

A previous heart attack or stroke, heart failure or kidney disease can influence which medicine is advised. Your doctor may also consider these treatments if your risk is high before any of these conditions develops. The benefit depends on the medicine and your health. These recommendations concern type 2 diabetes and should not be applied automatically to type 1 diabetes.

This is also why a doctor may suggest changing your prescription even when your sugar is controlled. You may need the medicine for its heart or kidney benefit, without needing a lower HbA1c.

We also need to consider your other medicines, kidney function, side effects and what you can afford to continue. With SGLT2 medicines, you need advice about dehydration, genital infections and the uncommon risk of ketoacidosis, a dangerous build-up of acids in the blood. Illness and prolonged fasting can increase that risk. GLP-1 medicines can cause nausea and other digestive problems and are not suitable for everyone. If you plan to fast or have a procedure, or become significantly unwell, ask which medicines need adjusting.

Dr. Kulin will discuss these choices with you and coordinate treatment with your primary diabetes care provider or endocrinologist.

What should my sugar target be?

Your target may differ from someone else's, even if you both have diabetes. Age, how long you have had diabetes, kidney function, heart disease and episodes of low sugar all influence what is safe for you.

If your sugar keeps dropping too low, or the prescription has become difficult to manage, tell your doctor. Treatment may need adjusting. Trying to achieve a lower reading at any cost can do harm.

If you have noticed any of the symptoms above, have an abnormal heart report or already have heart disease, a cardiology review can help. It can also be useful if you are unsure whether your medicines are giving you the heart protection you need, particularly when diabetes and kidney problems occur together.

You do not have to wait for symptoms to discuss prevention. If you feel well but have several risk factors, you can ask whether a cardiology assessment would add to the care you are already receiving. Not everyone with diabetes needs regular specialist visits or repeated heart tests.

Dr. Kulin will ask how you have been feeling, what you can comfortably do each day, how long you have had diabetes and which medicines you take. He will examine you and review your existing reports. Bring recent HbA1c, cholesterol, kidney function and urine albumin results if available.

Do I need heart tests if I have diabetes?

A heart checkup does not mean having every available test. Dr. Kulin will recommend a test when it can help answer something about your symptoms, heart function or treatment.

What can the different tests show?

Sometimes we also need to check for early problems with heart function. Blood tests called BNP or NT-proBNP may help with this in adults with diabetes. An abnormal result can lead to an echo. These tests are looking for possible heart failure, rather than blocked arteries.

Our testing guide explains what each cardiac test can and cannot show.

Can a CT calcium score help?

A coronary artery calcium score, often called a CAC score, measures calcium deposits within plaque in the heart's arteries. It is a CT scan done without a contrast injection.

It can help us understand your risk more clearly in some situations. But if the result would not change your treatment, there may be little reason to have the scan. It is not a test that everyone with diabetes needs.

The scan is most useful when its result could help settle an uncertain prevention decision. It has not been proven that routinely scanning everyone with diabetes who has no symptoms leads to better health outcomes.

If you have already had the scan, bring the report. Dr. Kulin will explain what the score means for you and whether anything needs to change.

Does diabetes mean I need angiography?

No. You do not need invasive coronary angiography simply because you have diabetes. If you have no symptoms and your heart risk factors are being treated, routinely looking for blockages with cardiac tests has not been shown to improve outcomes.

That changes if your symptoms or reports suggest a significant problem. Angiography may be advised if symptoms continue despite treatment, or if another test shows findings that need closer investigation. If a heart attack is suspected, you need emergency assessment.

For a planned review, your symptoms and existing reports help determine whether another test can provide the information needed or whether angiography is the appropriate next step.

Having angiography does not automatically mean you will need a stent. It is a test to look at the heart's arteries. Before a planned angiogram, ask why it is needed and what the possible findings would mean for your treatment. You can find more about what happens during coronary angiography on our procedure page.

If you have had a heart attack, a stent or bypass surgery, or are living with heart failure, bring both your heart and diabetes prescriptions to your review. We need to check how the medicines work together and whether your treatment still suits your health.

If you have significant blockages, diabetes can influence the choice between medicines, angioplasty and bypass surgery. Where the blockages are, how many arteries are involved, how well your heart pumps and whether surgery is suitable all matter. For some people with diabetes and complex blockages in several arteries, bypass surgery may offer an advantage over angioplasty. For others, medicines or angioplasty may be more appropriate. Some decisions benefit from discussion between the cardiologist and cardiac surgeon.

Our explanation of angioplasty and bypass surgery can help you prepare for that discussion. Diabetes alone does not decide which treatment you need.

At follow-up, we will ask how you feel, review your medicines and check the blood tests relevant to your treatment. You may need an earlier visit after a prescription change. If you develop new symptoms, get in touch rather than waiting for your next appointment.

You may want another discussion before deciding on a test or treatment. A second opinion can help you understand:

• Why angiography has been recommended and what it would change.
• What an abnormal calcium score or conflicting test results mean.
• Whether your prescription addresses both diabetes and cardiovascular risk.
• How medicines, angioplasty and bypass surgery compare in your circumstances.

Dr. Kulin personally reviews the reports and images you already have before deciding whether you need any further tests. Bring your prescriptions, recent blood reports and previous ECG, echo, stress-test or angiography records. He can explain the findings and discuss the options with you, alongside the care you are already receiving.

You can arrange a cardiologist consultation in Bopal for a non-emergency review.

If you have possible heart-attack symptoms or another emergency, seek immediate care. Do not delay treatment while arranging a second opinion.

Clinical guidance and references

• National Institute of Diabetes and Digestive and Kidney Diseases: Diabetes, Heart Disease and Stroke
• American Diabetes Association: Cardiovascular Disease and Risk Management, Standards of Care in Diabetes 2026
• ADA/EASD: Management of Type 2 Diabetes, 2026 Consensus Report
• American Diabetes Association: Pharmacologic Approaches to Glycemic Treatment, Standards of Care 2026
• American Diabetes Association: Glycemic Goals, Hypoglycemia, and Hyperglycemic Crises, Standards of Care 2026
• European Society of Cardiology: 2024 Guidelines for the Management of Chronic Coronary Syndromes
• ACC/AHA and partner societies: 2026 Guideline on the Management of Dyslipidemia
• American College of Radiology and Radiological Society of North America: Cardiac CT for Calcium Scoring
• American Heart Association: Warning Signs of a Heart Attack