---
title: Diabetes and the heart
description: Why diabetes raises the risk of coronary heart disease, heart attack and heart failure, why a heart attack in diabetes may come without typical pain, how risk is assessed, which treatment approaches clinical guidelines describe, and when to call an ambulance.
type: disease
aliases:
  - diabetes
  - diabetes mellitus
  - type 2 diabetes
  - T2DM
  - diabetes and heart disease
  - diabetes and coronary heart disease
  - diabetic cardiomyopathy
  - silent heart attack
  - silent myocardial infarction
sources:
  - tier: guideline
    org: esc
    title: 2023 ESC Guidelines for the management of cardiovascular disease in patients with diabetes
    year: 2023
    doi: 10.1093/eurheartj/ehad192
    url: https://doi.org/10.1093/eurheartj/ehad192
  - tier: guideline
    org: minzdrav-rf
    title: Сахарный диабет 2 типа у взрослых
    year: 2022
    url: https://cr.minzdrav.gov.ru/view-cr/290_2
  - tier: guideline
    org: nice
    title: 'Type 2 diabetes in adults: management (NG28)'
    year: 2026
    url: https://www.nice.org.uk/guidance/ng28
  - tier: reference
    org: msd-manuals
    title: Long-Term Complications of Diabetes Mellitus (MSD Manual Professional Version)
    year: 2025
    url: https://www.msdmanuals.com/professional/endocrine-and-metabolic-disorders/diabetes-mellitus-and-hypoglycemia/long-term-complications-of-diabetes-mellitus
  - tier: reference
    org: msd-manuals
    title: Long-Term Complications of Diabetes Mellitus (MSD Manual Consumer Version)
    year: 2025
    url: https://www.msdmanuals.com/home/hormonal-and-metabolic-disorders/diabetes-mellitus-and-low-blood-sugar-hypoglycemia/long-term-complications-of-diabetes-mellitus
  - tier: reference
    org: msd-manuals
    title: Acute Myocardial Infarction (MI) (MSD Manual Professional Version)
    year: 2026
    url: https://www.msdmanuals.com/professional/cardiovascular-disorders/coronary-artery-disease/acute-myocardial-infarction-mi
  - tier: reference
    org: msd-manuals
    title: Acute Coronary Syndromes (Unstable Angina and Heart Attack/Myocardial Infarction) (MSD Manual Consumer Version)
    year: 2026
    url: https://www.msdmanuals.com/home/heart-and-blood-vessel-disorders/coronary-artery-disease/acute-coronary-syndromes-unstable-angina-and-heart-attack-myocardial-infarction
  - tier: reference
    org: statpearls
    title: Silent Myocardial Ischemia
    year: 2024
    url: https://pubmed.ncbi.nlm.nih.gov/30725600/
sources_checked: 2026-10-14
review: null
---

Diabetes is an independent risk factor for atherosclerotic diseases of the heart and blood vessels.<Cite n={2} /> People with type 2 diabetes have a higher risk of cardiovascular disease than people with the same health-related characteristics and no diabetes.<Cite n={3} /> Cardiovascular disease is the main cause of death in people with type 2 diabetes.<Cite n={2} />

This article is about what diabetes does to the heart, not about treating diabetes itself. Individual conditions are covered in more detail in the articles on [coronary heart disease](../coronary-heart-disease/), [myocardial infarction](../myocardial-infarction/) and [heart failure](../heart-failure/).

<Diagram name="diabetes-and-heart">
  <p slot="normal">
    The diagram shows a coronary artery cut lengthwise. The coronary arteries deliver blood to the
    heart muscle.<Cite n={7} /> Here the artery wall is smooth, there are no plaques, and blood
    flows freely.
  </p>
  <p slot="disease">
    In diabetes, atherosclerotic diseases of the heart and blood vessels are more common,<Cite n={2} />
    and atherosclerosis, the build-up of plaques in the artery wall, starts at a younger age than
    in people without diabetes.<Cite n={5} /> Plaques narrow the artery and reduce blood flow to
    the heart.<Cite n={[5, 7]} /> In people with diabetes, the coronary arteries are often affected
    widely, in many places at once.<Cite n={2} />
  </p>
</Diagram>

## Why it happens

<Patient>

When blood sugar stays high for a long time, both small and large blood vessels narrow and blood flow through them falls.<Cite n={5} /> Poorly controlled blood sugar raises the level of fats in the blood, and atherosclerosis develops in the large arteries.<Cite n={5} /> Plaques narrow arteries of the heart, brain and legs, so diabetes leads to angina, heart attack, stroke and peripheral artery disease.<Cite n={5} />

Type 2 diabetes rarely comes alone: many people with it also have overweight or obesity, high blood pressure and abnormal blood fats.<Cite n={2} /> More about these in the articles on [hypertension](../hypertension/) and [dyslipidaemia](../dyslipidemia/).

Over time, narrowed blood vessels can also lead to [heart failure](../heart-failure/), a condition in which the heart pumps blood less well.<Cite n={5} /> In people with diabetes it is most often caused by coronary heart disease, but it can also develop without it.<Cite n={2} /> After a heart attack, heart failure develops more often in people with diabetes.<Cite n={[4, 5]} />

</Patient>

<Student>

According to the Russian Ministry of Health guideline, diabetes is an independent risk factor for ASCVD; it raises the risk of CHD 2–4-fold, and the prevalence of CVD in people with type 2 diabetes is 2–4 times that in people without diabetes.<Cite n={2} /> MSD: large-vessel atherosclerosis results from the hyperinsulinaemia, dyslipidaemia and hyperglycaemia characteristic of diabetes.<Cite n={4} /> Multivessel, diffuse coronary disease and marked coronary artery calcification are typical of diabetes.<Cite n={2} />

Risk factors for heart failure in diabetes according to ESC 2023: cardiac, namely ischaemic heart disease, myocardial infarction, hypertension, valvular heart disease and arrhythmias; non-cardiac, namely age, chronic kidney disease, increased body mass index, longer duration of diabetes, smoking and alcohol excess.<Cite n={1} /> CHD is the most common cause of chronic heart failure in type 2 diabetes, but a complex of pathophysiological changes can reduce coronary reserve and lead to heart failure without CHD.<Cite n={2} /> Among the possible causes of "diabetic cardiomyopathy", MSD names epicardial atherosclerosis, hypertension and left ventricular hypertrophy, microvascular disease, obesity and metabolic disturbances.<Cite n={4} />

</Student>

## Symptoms

<Patient>

Diabetes itself can go unnoticed for a long time, and without testing it is found years after it began.<Cite n={2} /> Not uncommonly, the first sign of type 2 diabetes is a heart attack or stroke.<Cite n={2} />

The key feature: coronary heart disease in diabetes is often painless or causes atypical symptoms.<Cite n={2} /> In people with diabetes, a heart attack can happen with no chest pain at all.<Cite n={7} /> Instead of pain there may be vague symptoms that the person does not recognise as illness; discomfort in the chest or abdomen is taken for indigestion.<Cite n={[6, 7]} /> Such a "silent" heart attack is sometimes found only later, on a routine ECG.<Cite n={7} /> Without pain, people do not seek help in time, and that is more dangerous to health and life.<Cite n={8} />

</Patient>

<Student>

Russian Ministry of Health guideline: CHD in diabetes is often asymptomatic, and type 2 diabetes is characterised by a high frequency of low-symptom (painless) and atypical CHD and MI.<Cite n={2} /> Without screening, the diagnosis of type 2 diabetes may be delayed by 7–9 years from onset; in 20–30% of patients the first manifestation is MI, stroke, loss of vision or another complication, and more than half already have CHD when type 2 diabetes is diagnosed.<Cite n={2} />

According to the same guideline, mortality in acute coronary syndrome is 2–3 times higher in people with diabetes.<Cite n={2} /> Silent myocardial ischaemia is reduced myocardial blood flow without noticeable symptoms; older patients with diabetes and those with prior MI or revascularisation are susceptible.<Cite n={8} />

</Student>

## How it is diagnosed

<Patient>

In people with diabetes, the doctor asks about symptoms of heart and blood vessel disease and looks for severe target-organ damage, that is, damage to the organs that suffer in diabetes.<Cite n={1} /> A resting ECG is recorded.<Cite n={2} /> If there are no signs of heart disease yet, the doctor assesses the risk, taking into account blood pressure, cholesterol, smoking, weight and waist size, and heart disease in close relatives.<Cite n={[1, 2]} />

If there are symptoms, coronary heart disease is looked for with the same tests as in people without diabetes.<Cite n={2} /> People with diabetes and no symptoms are not all given special tests for coronary heart disease: when symptoms are absent or atypical, the decision depends on risk factors.<Cite n={2} />

The doctor asks about symptoms of heart failure at every visit.<Cite n={1} />

The link also works the other way: everyone with heart or blood vessel disease is checked for diabetes with a fasting glucose and/or glycated haemoglobin (HbA1c) test.<Cite n={1} /> In acute coronary syndrome, glucose metabolism is assessed in every patient.<Cite n={1} />

</Patient>

<Student>

ESC 2023: in patients with type 2 diabetes without symptomatic ASCVD or severe target-organ damage, estimating 10-year CVD risk with SCORE2-Diabetes is recommended.<Cite n={1} /> ESC risk categories: very high, meaning clinically established ASCVD, severe target-organ damage or a 10-year risk of 20% or more; high, 10% to under 20%; moderate, 5% to under 10%; low, under 5%.<Cite n={1} />

Russian Ministry of Health guideline: routine screening for CHD in patients without clinical manifestations is not recommended.<Cite n={2} /> The same guideline allows diabetes to be diagnosed at an HbA1c of 6.5% (48 mmol/mol) or higher.<Cite n={2} />

</Student>

<HeartModel
  highlight={[
    'right-coronary-artery',
    'left-main-coronary-artery',
    'left-anterior-descending-artery',
    'circumflex-artery',
  ]}
/>

## How it is treated

<Patient>

Controlling blood sugar alone is not enough to protect the heart: a combined approach is needed, with control of blood pressure and blood fats, medicines that lower cardiovascular risk, stopping smoking, physical activity and weight loss if needed.<Cite n={[2, 4]} /> Risk factors and other conditions are looked for and treated early.<Cite n={1} /> Increasing any physical activity, even a little, is recommended.<Cite n={1} /> If there is a risk of coronary heart disease, an ECG is recorded before starting an exercise programme, and an exercise test if indicated.<Cite n={[1, 2]} />

Diabetes medicines are now judged not only by how they lower blood sugar but also by whether they protect the heart and kidneys.<Cite n={[1, 3]} /> Guidelines prefer medicines with proven benefit for the heart and blood vessels.<Cite n={1} /> Such benefit has been proven for medicines of two classes: SGLT2 inhibitors (gliflozins) and GLP-1 receptor agonists.<Cite n={[1, 2, 3, 4]} /> In people with atherosclerotic heart and blood vessel disease, they reduce cardiovascular events regardless of blood sugar level.<Cite n={[1, 2]} /> SGLT2 inhibitors also lower the risk of hospital admission for heart failure.<Cite n={[1, 2, 3]} />

Some diabetes medicines are undesirable in heart failure: for example, thiazolidinediones make the body hold on to salt and water.<Cite n={2} /> Very low blood sugar (hypoglycaemia) is avoided, especially in people with heart and blood vessel disease.<Cite n={[1, 2]} /> So the cardiologist and the endocrinologist should know about every medicine you take.

Cholesterol is lowered with statins first, and blood pressure is measured regularly to find and treat hypertension in time.<Cite n={1} /> Heart failure is treated the same way as in people without diabetes, and the treatments work equally well.<Cite n={2} /> Blood flow in the heart arteries is also restored with the same methods as in people without diabetes.<Cite n={1} /> Which medicines are needed and which treatment goals fit is decided by the doctor together with the patient; do not start, stop or change medicines on your own.

</Patient>

<Student>

ESC 2023: prioritise glucose-lowering agents with proven CV benefit, followed by agents with proven CV safety (I C); SGLT2 inhibitors and GLP-1 receptor agonists with proven CV benefit are recommended in type 2 diabetes with ASCVD to reduce CV events, independent of baseline or target HbA1c and of concomitant glucose-lowering medication (I A).<Cite n={1} /> Switching glucose-lowering treatment from agents without proven CV benefit or proven safety to agents with proven CV benefit is recommended.<Cite n={1} /> SGLT2 inhibitors are recommended in type 2 diabetes with multiple ASCVD risk factors or established ASCVD to reduce the risk of HF hospitalisation.<Cite n={1} />

Russian Ministry of Health guideline: with high ASCVD risk or established ASCVD, chronic heart failure or chronic kidney disease, adding an SGLT2 inhibitor or GLP-1 receptor agonist with proven benefit is a disease-modifying approach; SGLT2 inhibitors are recommended in chronic heart failure or at high risk of it to reduce the risk of death and HF progression; thiazolidinediones are not recommended in chronic heart failure.<Cite n={2} /> NICE NG28: SGLT2 inhibitors and GLP-1 receptor agonists are recommended as much for their cardiovascular and renal benefits as for their glycaemic benefits; managing type 2 diabetes should aim to improve health holistically rather than just meet HbA1c targets.<Cite n={3} />

</Student>

## When to call an ambulance

The main emergency danger to the heart in diabetes is a heart attack, which may come without typical pain.<Cite n={[2, 7]} /> Acute coronary syndromes are medical emergencies: many deaths from a heart attack occur in the first hours after symptoms begin.<Cite n={7} /> Call your local emergency number (112 in the EU, 911 in the US and Canada, 999 in the UK) at once if you have:

- pain, pressure or discomfort in the chest, especially spreading to the back, jaw or left arm;<Cite n={7} />
- shortness of breath, faintness or fainting, sudden heavy sweating, nausea;<Cite n={[6, 7]} />
- pain or discomfort in the abdomen that may be mistaken for indigestion; relief after belching does not rule out a heart attack.<Cite n={[6, 7]} />

Do not waste time calling friends or your own doctor: call an ambulance.<Cite n={7} /> The signs of a heart attack are described in more detail in the article on [myocardial infarction](../myocardial-infarction/), and the signs of acute heart failure in the article on [heart failure](../heart-failure/).

<Quiz />