Cardiac MRI Scan: Complete Guide

A cardiac MRI scan is the most detailed imaging technique available for assessing the heart's structure and function. Unlike echocardiography, a cardiac MRI provides high-resolution images of the heart muscle, valves, chambers, and surrounding blood vessels in exceptional detail. Through Lola Health, you can access private cardiac MRI scans at over 150 centres across the UK.

What a Cardiac MRI Scan Shows

• Heart muscle damage — scarring from previous heart attacks (myocardial infarction) and the extent of viable vs. damaged tissue.
• Cardiomyopathy — diseases of the heart muscle including dilated, hypertrophic, and restrictive cardiomyopathy.
• Myocarditis — inflammation of the heart muscle, often caused by viral infections.
• Heart valve disease — regurgitation or stenosis of the mitral, aortic, tricuspid, or pulmonary valves.
• Congenital heart defects — structural abnormalities present from birth.
• Pericardial disease — inflammation, thickening, or fluid around the heart (pericarditis, pericardial effusion).
• Cardiac tumours — benign or malignant masses within or adjacent to the heart.
• Aortic disease — aneurysms, dissection, or coarctation of the aorta.
• Ventricular function — precise measurement of ejection fraction and cardiac output.
• Iron overload — particularly relevant for patients with conditions such as thalassaemia or haemochromatosis.

When You Might Need a Cardiac MRI Scan

• Chest pain or tightness, particularly with exertion
• Shortness of breath that is unexplained or worsening
• Heart palpitations or irregular heartbeat
• Unexplained fatigue or reduced exercise tolerance
• A family history of cardiomyopathy or sudden cardiac death
• Abnormal ECG or echocardiogram findings requiring further investigation
• Assessment after a heart attack to determine the extent of damage
• Monitoring of known heart conditions or following cardiac surgery
• Elevated cardiac biomarkers (troponin) without a clear cause
• Assessment for competitive sports participation (cardiac screening)

How to Prepare for a Cardiac MRI

• Metal and devices: Most pacemakers and ICDs (implantable cardioverter-defibrillators) are now MRI-conditional, but verification with the scanning centre is essential. Inform them about any cardiac devices.
• Caffeine: You may be asked to avoid caffeine for 24 hours before the scan if a stress perfusion study is being performed.
• Fasting: A light fast of 2 to 4 hours may be recommended, particularly if contrast or stress agents are being used.
• Medications: Continue usual medications unless specifically advised otherwise. Beta-blockers may occasionally be given before the scan to slow the heart rate for clearer images.
• Clothing: Wear comfortable, metal-free clothing. A gown will typically be provided.

What to Expect During the Scan

1. ECG leads: Small electrodes are placed on your chest to synchronise the images with your heartbeat (ECG-gated imaging).
2. Positioning: You lie on your back on the scanner table. A cardiac coil is placed over your chest.
3. Breath-holds: You will be asked to hold your breath for short periods (10 to 15 seconds) at intervals during the scan to reduce motion from breathing.
4. Duration: A cardiac MRI typically takes 45 to 90 minutes, longer than most other MRI scans due to the complexity of the sequences.
5. Contrast: Gadolinium contrast is commonly used in cardiac MRI to assess tissue characterisation and scarring patterns.
6. Stress testing: Some protocols include the administration of adenosine or dobutamine to stress the heart during the scan, simulating the effects of exercise.
7. After: You can resume normal activities. If a stress agent was used, you may feel briefly flushed or short of breath, but this resolves quickly.

How Much Does a Cardiac MRI Scan Cost?

Private cardiac MRI scans in the UK typically cost between £500 and £1,200, reflecting the complexity and duration of the examination. Lola Health provides access to cardiac MRI at competitive prices, with appointments available across the UK and full consultant radiologist or cardiologist reporting.

Cardiac MRI and Blood Testing

Blood tests are a important complement to cardiac imaging, helping to assess heart health from a biochemical perspective:

• Lipid profile (cholesterol, LDL, HDL, triglycerides): High cholesterol is a major risk factor for coronary artery disease. Abnormal lipids alongside cardiac symptoms may prompt further investigation with MRI.
• BNP / NT-proBNP: These cardiac biomarkers are released when the heart is under strain. Elevated levels may indicate heart failure and support the need for cardiac MRI assessment.
• Troponin: Elevated troponin levels indicate heart muscle damage. If troponin is raised, cardiac MRI can help determine the cause and extent of injury.
• HbA1c: Diabetes is a major risk factor for cardiovascular disease. Blood glucose monitoring helps manage this risk.
• CRP (high-sensitivity): Inflammation plays a key role in cardiovascular disease. Elevated hs-CRP may indicate increased cardiac risk.
• Iron studies (ferritin, transferrin saturation): Iron overload can damage the heart muscle. Cardiac MRI can quantify iron levels in the heart tissue (T2* mapping).
• Thyroid function: Both overactive and underactive thyroid conditions can affect heart rhythm and function.

Start with a Lola Health blood test to check your cholesterol (LDL, HDL, triglycerides), HbA1c, CRP, and NT-proBNP. If results suggest further investigation, a cardiac MRI can provide the structural detail your blood results can't show. Peak Insights 70 covers these markers across 70 biomarkers.

Consider a full health check from Lola Health to accompany your cardiac MRI.

Considering a broader check? Read our full body MRI scan guide to see what a complete MRI screening covers, or explore the Peak 70 + Full Body MRI bundle for the most thorough health check available.

Frequently Asked Questions

Is a cardiac MRI safe?

Yes. Cardiac MRI does not use ionising radiation and is considered very safe. The main consideration is compatibility of any cardiac devices such as pacemakers.

How long does a cardiac MRI take?

Typically 45 to 90 minutes, depending on the complexity of the study and whether stress testing or contrast is included.

Can I have a cardiac MRI with a pacemaker?

Many modern pacemakers are MRI-conditional, meaning they can be scanned under specific conditions. This must be confirmed with the scanning centre and your cardiologist before the appointment.

Is a cardiac MRI better than an echocardiogram?

They serve complementary roles. Echocardiography is quicker and more widely available, while cardiac MRI provides superior tissue characterisation, more precise measurements, and better visualisation of certain conditions.

Do I need a referral?

No GP referral is needed for a private scan through Lola Health.

What is the difference between a cardiac MRI and an angiogram?

A cardiac MRI assesses the heart muscle, valves, and overall structure non-invasively. A coronary angiogram is an invasive procedure that specifically visualises the coronary arteries to detect blockages.

Will I feel anything during the scan?

You will not feel the magnetic field or radio waves. If contrast is used, you may feel a brief cool sensation. If stress agents are administered, temporary flushing, warmth, or shortness of breath is normal.