Myocardial perfusion imaging, planar (including qualitative or quantitative wall motion, ejection fraction by first pass or gated technique, additional quantification, when performed); multiple studies, at rest and/or stress (exercise or pharmacologic) an
CPT4 code
Name of the Procedure:
Myocardial Perfusion Imaging, Planar (including qualitative or quantitative wall motion, ejection fraction by first pass or gated technique, additional quantification, when performed); Multiple Studies, at Rest and/or Stress (exercise or pharmacologic)
Summary
Myocardial perfusion imaging (MPI) is a non-invasive imaging test that shows how well blood flows through (perfuses) the heart muscle. This procedure is often done in two parts: one at rest and one under stress conditions which can be induced by exercise or medication.
Purpose
Myocardial perfusion imaging is used to diagnose coronary artery disease, assess the severity and impact of known heart diseases, and guide treatment decisions. The expected outcomes include accurate diagnosis and assessment of heart function and blood flow.
Indications
MPI is recommended for individuals experiencing chest pain, shortness of breath, or other symptoms of compromised blood flow to the heart. It’s also appropriate for patients with known heart conditions, those undergoing preoperative evaluation for non-cardiac surgery, or for risk assessment in individuals with multiple risk factors for heart disease.
Preparation
Patients are usually instructed to avoid eating or drinking for a few hours before the procedure. Some medications may need to be adjusted or temporarily discontinued. Patients should also avoid caffeine and smoking for at least 24 hours prior.
Procedure Description
- Injection of Radioactive Tracer: A small amount of radioactive tracer is injected into the bloodstream.
- Rest Imaging: Images of the heart are taken while the patient is at rest to measure baseline blood flow.
- Stress Imaging:
- Exercise Stress: Patients may walk on a treadmill or pedal a stationary bike to elevate their heart rate.
- Pharmacologic Stress: For those unable to exercise, medication is administered to mimic the effects of exercise.
- Second Injection and Imaging: Another tracer injection and a second set of images are taken under the stress condition.
- Image Analysis: Both sets of images are compared to evaluate blood flow and heart function.
The procedure uses specialized gamma cameras and possibly SPECT (Single Photon Emission Computed Tomography) or PET (Positron Emission Tomography) scanners.
Duration
The entire procedure, including preparation and resting periods, usually takes 3-4 hours.
Setting
The procedure is typically performed in a hospital's nuclear medicine department or in a specialized outpatient imaging center.
Personnel
The procedure involves nuclear medicine technologists, a radiologist or nuclear medicine physician to interpret the images, and potentially a cardiologist for clinical assessment and stress testing.
Risks and Complications
- Common Risks: Mild reactions to the tracer, such as nausea or rash.
- Rare Risks: More significant allergic reactions, dizziness, or heart arrhythmias during stress.
Benefits
MPI provides detailed images of heart blood flow, aiding in accurate diagnosis and effective treatment planning. Most patients experience results within a few days, leading to timely medical interventions.
Recovery
Post-procedure care typically involves monitoring for a short time to ensure no immediate side effects. Patients are usually advised to drink plenty of fluids to help flush the tracer from their body. Normal activities can often be resumed the same day.
Alternatives
Other diagnostic tests include:
- Exercise Stress Test: Assessing heart function under stress without imaging.
- Echocardiogram: Using ultrasound to create heart images.
- Cardiac MRI or CT Scan: Providing detailed heart images through different technologies.
Each alternative has its own advantages and disadvantages in terms of detail, cost, and availability.
Patient Experience
Patients may feel nervous about the injection or stress testing, but discomfort is typically minimal. Most patients report mild fatigue or soreness if they perform the exercise segment. Pain management and comfort measures, such as ensuring a calm environment and clear communication, are provided.