Heart Health Pathway: Cholesterol Test to Cardiac MRI

Heart disease is the UK's second biggest killer. The path from a cholesterol blood test to a cardiac MRI is one of the most important health pathways to understand — because catching heart problems early can genuinely save your life. This guide traces the complete journey from your first lipid panel to a detailed cardiac MRI, explaining every number and decision point along the way.

Step 1: Your Cholesterol Blood Test

Understanding Your Lipid Panel

Marker	What It Is	Target Level	Red Flag Level
Total Cholesterol	All cholesterol combined	<5.0 mmol/L	>7.5 (possible FH)
LDL Cholesterol	"Bad" cholesterol — builds up in arteries	<3.0 mmol/L	>4.9 (possible FH)
HDL Cholesterol	"Good" cholesterol — removes LDL	>1.0 (men), >1.2 (women)	<0.9 (increased risk)
Triglycerides	Fat in the blood	<1.7 mmol/L	>2.3 (needs treatment)
Non-HDL Cholesterol	Total minus HDL — best single risk marker	<4.0 mmol/L	>5.0 (high risk)
Total:HDL Ratio	Risk ratio	<4.0	>6.0 (high risk)

Additional Cardiac Blood Markers

A thorough cardiac risk assessment includes more than just cholesterol:

• hsCRP: Inflammation marker for cardiovascular risk. <1 mg/L = low risk, 1–3 = moderate, >3 = higher risk.
• Lp(a) — Lipoprotein(a): Genetically determined. Elevated Lp(a) (>50 nmol/L) is an independent risk factor for heart disease. Cannot be lowered by lifestyle changes.
• HbA1c: Diabetes significantly increases cardiovascular risk. <42 mmol/mol is normal.
• NT-proBNP: A heart failure marker. Elevated levels suggest the heart is under strain.

Step 2: Assessing Your Overall Risk

Cholesterol numbers alone don't tell the full story. Your overall cardiovascular risk depends on:

• Your age and sex
• Blood pressure
• Smoking status
• Family history of heart disease
• Diabetes status
• Ethnicity (South Asian ethnicity carries higher risk)
• Kidney function

Your GP will calculate your QRISK3 score — a percentage representing your 10-year risk of a heart attack or stroke. A score above 10% usually triggers statin therapy. A score above 20% is considered high risk.

Step 3: When to Progress to Cardiac Imaging

Not everyone with high cholesterol needs a cardiac MRI. Imaging becomes relevant when:

You Have Symptoms

• Chest pain or tightness (especially on exertion)
• Breathlessness that's new or worsening
• Unexplained fatigue that limits your activities
• Palpitations or irregular heartbeat
• Ankle swelling

You're High Risk Without Symptoms

• QRISK3 score >20%
• Familial hypercholesterolaemia (FH) confirmed or suspected
• Family history of premature heart disease (men <55, women <65)
• Known to carry elevated Lp(a)
• Diabetes with additional risk factors

Previous Tests Showed Abnormalities

• ECG showing ischaemic changes, left ventricular hypertrophy, or arrhythmia
• Echocardiogram showing reduced ejection fraction, valve abnormalities, or wall motion abnormalities
• CT calcium score showing significant coronary calcification

Step 4: The Cardiac MRI

Cardiac MRI is the gold standard for assessing heart muscle. Here's what happens:

Before the Scan

• No special preparation needed (you can eat and drink normally)
• Wear comfortable clothes without metal
• You'll have an ECG attached (small stickers on your chest) so the scanner can time images to your heartbeat
• An IV line for gadolinium contrast (usually administered partway through)

During the Scan (45–60 minutes)

• You'll lie on your back in the scanner
• The radiographer will ask you to hold your breath at intervals (10–15 seconds each time) — this keeps your heart still for the images
• Multiple sequences are acquired: cine (moving heart), flow mapping, perfusion (blood flow), and late gadolinium enhancement (scar detection)

What the Scan Measures

• Ejection fraction (EF): Normal is 55–70%. Below 40% indicates significant heart failure.
• Wall motion: Each segment of the heart muscle should contract evenly. Reduced motion in a segment suggests ischaemia or previous damage.
• Myocardial perfusion: Blood flow to the heart muscle. Reduced perfusion during stress indicates coronary artery disease.
• Late gadolinium enhancement (LGE): Detects scar tissue from previous heart attacks (even ones you didn't know you had). Also detects fibrosis from cardiomyopathy, myocarditis, or infiltrative diseases.
• Valve function: Flow mapping quantifies any valve leaking or narrowing.
• Cardiac masses: Tumours, thrombus (blood clots), or other structural abnormalities.

Step 5: Understanding Your Results

• Normal cardiac MRI: Reassuring. Your heart structure and function are intact despite elevated cholesterol. Continue risk factor management (statins, lifestyle) and recheck bloods annually.
• Reduced ejection fraction: Heart failure. Referral to cardiology. Treatment depends on severity and cause.
• Myocardial ischaemia detected: Coronary artery disease is likely. Your cardiologist may recommend CT coronary angiography, invasive angiography, or stress testing to plan treatment.
• Scar tissue (LGE positive): Evidence of previous heart damage. Could be from a silent heart attack, myocarditis, or cardiomyopathy. Cardiology follow-up needed.
• Cardiomyopathy found: Disease of the heart muscle (hypertrophic, dilated, or arrhythmogenic). Specialist management, possible genetic testing for family members.

Cost of the Complete Heart Health Pathway

Step	Test	Cost
1	Peak 70 Blood Test (includes full lipid panel, HbA1c, CRP)	£230
2	GP consultation (if needed — NHS or private)	Free (NHS) or £50–£100 (private)
3	Cardiac MRI	£349
	Total (blood test + cardiac MRI)	£579

For comparison: a Prenuvo full body MRI costs £2,499 and doesn't include blood testing or detailed cardiac-specific sequences.

Related Guides

• High Cholesterol → Cardiac MRI
• HbA1c and Diabetes → Scanning
• When Blood Tests Suggest You Need a Scan
• Blood Test Then Scan: Complete Pathway
• Private MRI Scan Cost UK (2026)
• MRI Scan Cost by Body Part