Cardiac viability PET scan: what to expect

After reduced blood flow or a previous heart injury, some muscle may contract weakly but remain alive. Other areas may be replaced by scar tissue. A viability PET scan examines how heart muscle uses glucose, helping the cardiology team distinguish potentially recoverable tissue from tissue that is less likely to regain function.

The result is one part of treatment planning. It may be considered with an echocardiogram, cardiac MRI, stress testing, symptoms, and coronary anatomy. PET findings do not predict an outcome with certainty and do not replace a discussion about the possible benefits and risks of revascularisation or other treatment.

The imaging centre will give detailed instructions about fasting, meals, carbohydrate intake, exercise, and diabetes medicines. These steps help control the heart’s normal fuel use so FDG uptake can be interpreted more clearly. Tell the team about diabetes, pregnancy or breastfeeding, allergies, and all medicines before the appointment.

You receive FDG through a vein and rest quietly during the uptake period. Then you lie on a PET-CT scanner while it records images. Keep still and follow breathing instructions. Because preparation and uptake take time, plan for a longer visit than the image collection alone. Follow the centre’s advice afterward about drinking, activity, and contact with vulnerable people.

Call for urgent help if you develop severe chest pressure, sudden breathlessness, collapse, or a new persistent fast or irregular heartbeat. These symptoms require prompt medical assessment rather than waiting for the imaging report. Tell the imaging service about a worsening injection-site reaction, dizziness, or any unexpected problem after the tracer.

Ask what decision the viability scan may inform, how your diabetes plan will be managed, and whether another heart imaging test is also needed. Ask what the possible findings could mean for medicines, revascularisation, device treatment, or follow-up, and who will explain the report.