How to plan a cardiac MRI viability protocol (Part 1)

This step-by-step guide is for MRI students, radiographers and technologists who wish to improve their planning skills and master the cardiac viability MRI protocol.

This guide is Part 1 of a cardiac viability assessment. This first part will focus on:

• Cardiac function: The pumping action of the heart
• Morphology: The shape, structure, and size of the heart

In Part 2, we will cover tissue characterization, where we determine which damaged parts of the myocardium can recover with treatment, and which are permanently scarred.

What you will learn in this Part 1:

1. Key factors in cardiac viability MRIs, including trade-offs.
2. Patient and scanner setup tips.
3. Best pulse sequences and planning techniques.
4. Ways to avoid common artifacts.
5. What great cardiac viability images should look like.

The heart is a vital organ that pumps blood throughout the body, delivering oxygen and nutrients to tissues. Heart disease remains the leading cause of death worldwide, so accurate heart imaging is key for diagnosis and treatment.

Cardiac viability MRI protocols are important for evaluating myocardial damage caused by poor blood flow, often due to heart attacks or coronary artery disease (CAD).

These exams help us determine:

1. Which parts of the heart muscle are still alive and can recover.
2. Which areas are permanently scarred.

This information guides treatment decisions such as revascularization or bypass surgery.

How to Balance the 3 Trade-offs in Cardiac Viability MRIs

In MRI, we always face a trade-off between 3 key metrics:

1. Scan Time: How fast a pulse sequence can be completed.
2. Resolution: How much detail the image can display.
3. SNR: How clear the image is, how much signal relative to noise.

Improving one of these metrics reduces the performance of the others. To decide what trade-offs to make, we must consider the needs of each clinical situation.

In cardiac viability MRIs:

• The main goal is to clearly distinguish between scarred and healthy heart muscle.
• The depth and extent of damage can be just 1–2 mm, so we also need good resolution.
• Scan time matters, but we can often afford a bit more time if the patient can cooperate.

Therefore, we typically:

1. Prioritize SNR to clearly distinguish scarred tissue from healthy myocardium, which is the whole point of viability imaging.
2. Maintain enough resolution to assess scar depth, since the extent of damage can be just 1-2 mm.
3. Optimize scan time last, keeping it practical, since patients undergoing viability imaging can generally cooperate with a somewhat longer scan.

This balance ensures we clearly see bright scar tissue against the dark, viable myocardium, which is the whole point of viability imaging.

Cardiac Viability/MI Health Conditions – And the MRI Sequences That Reveal Them

The cardiac viability/MI MRI study can help us diagnose a wide range of heart conditions.

In this article, we focus specifically on conditions related to:

1. Cardiac Function: The pumping action of the heart, and
2. Morphology: The shape, structure, and size of the heart.

The table below lists some of the most common cardiac conditions related to these two aspects, and what pulse sequences reveal them:

This step-by-step guide below will show you how to set up and perform a cardiac viability MRI protocol in practice, focusing specifically on the morphology and function aspects of viability.

We will perform the protocol in 3 parts:

1. Set up the Patient and MRI Scanner
2. Plan and Acquire the Protocol Sequences
3. Review the Images

Step 1: Set up the Patient and MRI Scanner

1. Instruct the Patient to Hold Their Breath

Breath-holding is necessary in cardiac MRI to avoid motion artifacts from the diaphragm and chest wall.

When a patient breathes during a scan, the heart and surrounding structures shift, which causes image blurring or ghosting.

To prevent this, we ask the patient to hold their breath at the end of exhale, which is the most stable phase of the breathing cycle.

🗣️ Example – How to Instruct the Patient:

Let the patient practice once or twice before scanning. Watch their breathing pattern and give coaching if needed.

Cardiac MRI requires many repeated breath-holds. A function and morphology study needs roughly 15 to 20. A full viability study including the post-contrast sequences can need 25 to 30, so plan breaks between sequences.

If the patient has trouble with breath-holds (e.g., due to age, heart failure, or lung disease), use faster scan techniques or consider free-breathing alternatives with motion correction.

The black and bright blood sequences are acquired during free breathing. Breath-holding starts with the cine sequences and continues through the post-contrast series.

2. Position the Patient and the Coils

Lay the patient feet-first and supine (on their back) with the chest aligned at the scanner’s isocenter.

Using a feet-first position makes the scan feel less claustrophobic for the patient, which reduces the risk of motion artifacts.

Use a dedicated cardiac coil to ensure high-resolution imaging. This coil provides strong signal reception and full coverage of the heart.

✅ Correct Patient Positioning:

3. Place ECG Electrodes and ECG-Gate the Scan

ECG-gating means we use the patient’s electrocardiogram (ECG) to capture each image at the same time point during each heartbeat.

Without gating, images may be acquired during different cardiac phases (points in time during a heartbeat), which leads to motion artifacts caused by heart movement.

To ECG-gate, you need to place three ECG electrodes on the patient’s chest, as shown in the image below:

These electrodes connect to the MRI-compatible ECG box, which tracks the heart’s electrical signal.

For this scan, we rely on a regular RR interval, meaning the patient has a normal sinus rhythm with consistent timing between beats.

If the patient has a heart condition, such as arrhythmia, they may have irregular timing between diastole and systole of the cardiac cycle. This variation can cause missed triggers or skipped beats, which result in artifacts or blurred images.

That’s why it’s necessary to check the ECG signal before you begin.

1. Make sure the ECG trace is strong, clean, and stable while positioning the patient.
2. Check that the electrode pads are secure and that the cables don’t shift with breathing or movement.

The ECG trace is your guide for the entire scan.

If it’s unstable or disconnects during scanning, image quality may suffer.

4. Check the Scanner’s Hardware Settings

Once the patient is in place, review your scanner’s hardware settings.

In this guide, we will use the following settings:

This hardware setup is widely used in clinical practice. It balances acquisition time, image quality, and patient comfort.

5. Capture the Initial Localizer Images

Before we can perform any MRI protocol, we must always capture initial localizer images of the patient. These images act as a guide for planning the detailed scans we will perform next.

We should always capture localizers in three planes:

1. Axial
2. Sagittal
3. Coronal

Once acquired, load the initial localizer images into the three viewports.

Then, scroll through each of the image stacks to locate a central slice that clearly shows the anatomy of the heart.

✅ Correct Setup of Localizer Images for Cardiac Viability MRI:

Step 2: Plan and Acquire the Protocol Sequences

When all preparations are ready, we can start planning and acquiring the protocol sequences.

Let's go through the pulse sequences a standard cardiac viability MRI protocol includes, why we perform them, and how to set them up.

The 8 Sequences of a Standard Cardiac Viability Protocol – Function & Morphology

1. Black Blood (Extra-Cardiac Anatomy, IR-bSSFP)
2. Bright Blood (Intra-Cardiac Anatomy, IR-TSE)
3. Pseudo 2-chamber View (bSSFP)
4. Pseudo Short-Axis (SAX) View (bSSFP)
5. 4-chamber Cine Imaging (bSSFP)
6. 2-chamber Cine Imaging (bSSFP)
7. LVOT / 3-chamber Cine Imaging (bSSFP)
8. SAX Stack Cine Imaging (bSSFP)

As you can see from this list above, we mainly use two types of sequences for this study:

• Inversion Recoveries: The black and bright sequences both use inversion recovery to examine cardiac structure and detect extra-cardiac findings like effusions.
• Cine Imaging: Cines capture the heart's motion like a live movie, which lets us evaluate how the heart muscle moves and identify areas with reduced wall motion.

Both types of sequences use ECG-gating to reduce motion artifacts and thus improve image quality.

In the sections below, we go through how to plan and set up each sequence.

1. Black Blood (Extra-Cardiac Anatomy, IR-bSSFP)

The black blood sequence helps us see extra-cardiac structures, pericardial effusions, and fat infiltration. This sequence is ECG-gated but acquired during free breathing, so expect some respiratory ghosting near the anterior chest wall.

✅ Correct Planning:

Planning Instructions:

• Add enough slices to cover from the lung apices down through the diaphragm, capturing the full heart and mediastinum.
• Use appropriate slice parameters:
  • Slice thickness: 6 mm
  • Slice gap: 2 mm
• Align the slices as follows:
  • Sagittal localizer: Identify the top of the lungs and the lowest point of the diaphragm posteriorly. These define the superior and inferior boundaries of the slice stack.
  • Coronal localizer: Confirm the same superior-to-inferior boundaries and center the stack over the heart and mediastinum.
• Plan the acquisition in the axial plane.
• Set the fold-over direction (phase encoding) to anterior-posterior to reduce respiratory artifacts.

Parameters for Black Blood (IR-bSSFP):

2. Bright Blood (Intra-Cardiac Anatomy, IR-TSE)

The bright blood sequence shows intra-cardiac anatomy and chamber dimensions. This sequence is ECG-gated but acquired during free breathing, so expect some respiratory ghosting near the anterior chest wall.

✅ Correct Planning:

Planning Instructions:

• Copy the slice geometry and planning from the black blood sequence.
• Keep the same slice angulation, coverage, and positioning to ensure images of different contrasts can be clearly compared.

Parameters for Bright Blood (Intra-Cardiac Anatomy, IR-TSE):

The heart sits at an angle to the body axes, rotated from right to left and from posterior to anterior, so its long axis does not line up with the axial, sagittal or coronal planes. Cardiac views are therefore planned as oblique planes and named after the chambers they show, such as 2-chamber or 4-chamber. Views labelled pseudo are quick, low-resolution versions acquired only to plan the diagnostic cines that follow. In the planning instructions below, plane names identify the viewport holding each reference image, not the anatomical plane of the view itself.

3. Pseudo 2-Chamber View (bSSFP)

This localizer helps us plan the actual diagnostic sequences by capturing a preliminary view of the left atrium and left ventricle.

✅ Correct Planning:

Planning Instructions:

• Use the left ventricle, mitral valve, and left atrium as your anatomical references.
• Align the slices as follows:‍
  
  • Axial localizer: Rotate the slice so it passes through the apex of the left ventricle and the center of the mitral valve, forming a clean long-axis line through both left-sided chambers.‍
  • Coronal localizer: Center the slice over the left heart, avoiding the right-sided chambers.
• Set the fold-over direction (phase encoding) to anterior-posterior to minimize respiratory motion artifacts.

Parameters for Pseudo 2-Chamber View (bSSFP):

✅ Pseudo 2-Chamber View – Correct Image Example:

Things to Look for:

• Slice runs from mitral valve to apex
• Left atrium and left ventricle are clearly visualized
• Bright blood pool with minimal artifact
• No wrap or banding artifacts
• Chamber walls appear uniform and symmetric

4. Pseudo Short-Axis (SAX) View (bSSFP)

This localizer creates a perpendicular reference to the two-chamber view for planning the cine sequences. This stack helps identify structures to exclude later when refining the final 2-chamber view.

✅ Correct Planning:

Planning Instructions:

• Clone the previous pseudo 2-chamber sequence and copy the same slice geometry to use as a starting point.
• Use the mitral valve plane, left atrium, and proximal left ventricle as your anatomical references.
• Align the slices as follows:
  • Sagittal pseudo 2-chamber: Rotate the slice so it runs parallel to the mitral valve plane. This defines the pseudo short-axis orientation.
  • Axial localizer: Confirm the slices remain parallel to the mitral valve plane, perpendicular to the long axis of the heart. Plan to include 3–4 slices:
    • One slice at the mitral valve
    • One slice above to include the aorta, pulmonary artery, and left atrial appendage
    • One or two slices below to include part of the left ventricle
• Set the fold-over direction (phase encoding) to right-left to align the phase with the short-axis view, which avoids wrap-around artifacts from anterior/posterior chest.

Parameters for Pseudo Short-Axis (SAX) View (bSSFP):

✅ Pseudo SAX View – Correct Image Example:

Things to Look for:

• Image aligned perpendicular to mitral valve plane
• Visualizes mitral valve, aortic root, and base of LV
• Bright blood with sharp chamber walls
• Clear view of left atrial appendage and PA
• Minimal motion or off-axis distortion

5. 4-Chamber Cine Imaging (bSSFP)

This diagnostic view shows all four heart chambers simultaneously, allowing assessment of their relationship.

✅ Correct Planning:

Planning Instructions:

Parameters for 4-Chamber Cine Imaging (bSSFP):

A cine is normally reconstructed into 20 to 25 cardiac phases, which is enough to show the full cycle including end-diastole and end-systole. Where a patient cannot hold their breath, a free-breathing cine with signal averaging is the alternative, at the cost of a longer acquisition.

6. 2-Chamber Cine Imaging (bSSFP)

The 2-Chamber view focuses specifically on the left atrium and left ventricle.

✅ Correct Planning:

Planning Instructions:

• Clone the previous 4-chamber cine sequence and copy the slice geometry as a starting point.
• Keep the same sequence parameters to ensure the different cine views maintain the same contrast so they can be clearly compared.
• Use the left atrium, left ventricle, and mitral valve as your anatomical references.
• Align the slices as follows:
  • Axial cine 4-chamber: Adjust the angulation of the field of view to follow the long axis of the left heart, avoiding overlap with the right-sided chambers. Ensure the slice remains centered on the left atrium and ventricle.
  • Coronal pseudo SAX: Slightly rotate the slice clockwise to avoid the pulmonary artery. Center the slice to run cleanly through the mitral valve and the left ventricular apex.

Parameters for 2-Chamber Cine Imaging (bSSFP):

7. LVOT / 3-chamber Cine Imaging (bSSFP)

The 3-Chamber view shows the left ventricular outflow tract (LVOT), providing important information about the aorta.

✅ Correct Planning:

Planning Instructions:

• Clone the previous 2-chamber cine sequence and copy the slice geometry as a starting point.
• Use the left atrium, left ventricle, aortic root, and apex as your anatomical references.
• Align the slices as follows:
  • Coronal pseudo SAX: Angle the slice through the center of the aorta and the middle of the left atrium, following the outflow tract. Avoid including the pulmonary artery or right ventricle.
  • Sagittal 2-chamber cine: Fine-tune the angle so the slice also passes through the apex of the left ventricle and the mitral valve, following the left ventricle’s long axis.
• This produces a true LVOT (3-chamber) view, showing the left ventricle, aortic valve, ascending aorta, and left atrium in one plane.

Parameters for LVOT / 3-chamber Cine Imaging (bSSFP):

8. Short-Axis (SAX) Stack Cine (bSSFP)

The Short-Axis stack provides multiple slices from the base to the apex of the heart, allowing for volumetric measurements.

✅ Correct Planning:

Planning Instructions:

• Plan the stack using the 2-chamber cine, 4-chamber cine, and pseudo short-axis views.
• Use the left ventricle, posterior wall, and interventricular septum as your anatomical references.
• Align the slices as follows:
  • Sagittal 2-chamber cine: Rotate the slice package so it is perpendicular to the posterior wall of the left ventricle. Position the slice stack through the center of the left ventricle and move it slightly downward to optimize coverage.
  • Axial 4-chamber cine: Align slices perpendicular to the interventricular septum, to follow the heart’s true short axis.
• Set the fold-over direction (phase encoding) to foot-head (FH), which is the in-plane direction for this short-axis stack and keeps wrap from the chest and arms outside the heart.
• Plan for short breath-hold durations:
  • Total acquisition time for the stack should stay at roughly 1.5 minutes.
  • Across 9–12 slices this works out to about 7–9 seconds per slice, which is the length of each breath-hold.

Parameters for Short-Axis (SAX) Stack Cine (bSSFP):

How to Avoid Artifacts When Planning the Sequences

The table below lists the 6 common cardiac artifacts, and what techniques you can use to avoid them:

Step 3: Review the Images

Finally, we will review the images to ensure all the anatomical information we need is clear.

In a cardiac viability MRI focused on morphology and function, these structures must be clearly visible:

1. Left and right ventricles: Including clear borders of the endocardium and epicardium.
2. Interventricular septum: Check position, motion, and thickness.
3. Left and right atria: With visible appendages if possible.
4. Aorta and pulmonary artery: Including outflow tracts and valve motion.
5. Pericardium: Assess for effusion or thickening.
6. Diaphragm and posterior lung bases: To check for pleural effusion.

Below, we will go through all the different image contrasts and explain their specific role in imaging the heart.

Black Blood IR-bSSFP – Nulls Blood Signal for Clear Morphological Borders

The black blood uses an inversion recovery to null the signal from flowing blood. This makes moving blood appear black while static tissues like myocardium and fat appear gray/bright. The strong contrast lets us inspect extra-cardiac anatomy, vessel walls, and tissue boundaries.

In cardiac viability imaging, black blood is vital for assessing morphology. It helps identify pericardial thickening, pleural effusion, and fat infiltration. It also confirms proper planning and helps visualize lung bases, diaphragm, and adjacent chest anatomy.

✅ Black Blood IR-bSSFP – Correct Image Example:

Things to Look for in Black Blood:

• Vessels (aorta, vena cava) should be fully black, with no residual signal.
• No pleural effusion, which would appear as bright fluid in the lower back part of the lungs.
• Liver and biliary ducts may appear bright, as these contain static fluids.
• Diaphragm and lung apices should be visible with no distortion.
• Clear view of pericardium and adjacent fat or thickening.
• Respiratory ghosting near the anterior chest wall, which is expected in a free-breathing acquisition and acceptable as long as it does not overlie the heart.

Bright Blood IR-TSE – Enhances Blood Signal to Show Chamber Structure

This sequence uses a T2-weighted TSE readout with fat suppression. The long TR and long effective TE make the blood pool and static fluids bright, while suppressed fat sharpens the contrast at chamber and pericardial borders. It shows the blood pool, chamber size, and great vessels clearly, with sharp contrast and reduced motion artifacts.

In viability protocols, bright blood is also used to examine morphology, specifically intra-cardiac anatomy, dilation, septal shift, and large effusions.

✅ Bright Blood IR-TSE – Correct Image Example:

Things to Look for in Bright Blood:

• Aorta, pulmonary artery, and chambers should appear uniformly bright.
• All four chambers must be visible without distortion or wrap artifacts.
• Check for clear boundary between blood pool and myocardium.
• Look for signs of chamber enlargement or septal shift.
• Fluid (pleural or pericardial) may appear brighter than on black blood.
• No fat-suppression failure over the anterior chest wall, and no flow ghosting across the chambers.

Cine Imaging – Evaluate Cardiac Motion and Chamber Contraction

Cine imaging uses a fast, ECG-gated sequence to capture the heart through multiple cardiac phases. It shows the heart beating like a movie across systole and diastole.

Cine is the gold standard for evaluating global function, such as ejection fraction, wall motion, and ventricular contractility.

In cardiac viability studies, cine images are a must to:

• Track ventricular wall thickening and motion.
• Visualize valve function and blood flow direction.
• Compare end-diastolic and end-systolic phases to calculate EF (Ejection Fraction).

✅ 4-Chamber Cine bSSFP of the Heart – Correct Image Example:

Note that the 4-chamber cine image above shows a minor wrapping artifact at its top. But since it doesn’t interfere with the anatomy of the heart, it still meets diagnostic quality.

Things to Look for in 4-Chamber Cine:

• All four chambers should be visible and centered.
• Mitral and tricuspid valves should open and close fully.
• Ventricular walls should contract evenly, especially in the left ventricle.
• Blurring or ghosting, which may indicate missed ECG triggering.
• Artifacts from metal devices like pacemakers or loop recorders.
• Endocardial and epicardial contours are sharp and traceable.

✅ 2-Chamber Cine bSSFP of the Heart – Correct Image Example:

Things to Look for in 2-Chamber Cine:

• Slice must run through mitral valve and apex.
• Left atrial appendage should be visible (shows good alignment).
• Avoid including the right ventricle. Keep the view clean.
• Myocardium should thicken in systole and relax in diastole.
• Crisp motion, without delay or double-exposure.

✅ 3-Chamber (LVOT) Cine bSSFP of the Heart – Correct Image Example:

Things to Look for in 3-Chamber (LVOT) Cine:

• Slice must pass through left atrium, aortic valve, and apex.
• Aortic outflow tract should show clearly, including valve opening.
• Smooth transition of blood into the aorta.
• Mitral-aortic continuity, no distortion or artifacts.
• Basal septal motion and LVOT narrowing.

✅ Short-Axis Stack Cine of the Heart – Correct Image Example:

Things to Look for in Short-Axis Stack Cine:

• Stack should cover apex to base without missing slices.
• Wall motion must be smooth and symmetric across all levels.
• Endocardial and epicardial contours should be easy to trace.
• Hypokinetic or akinetic segments that do not contract fully.
• Systolic thickening should be visible in healthy myocardium.
• Breathing artifacts (check anterior-posterior motion blur).

Phase swap: if a bright area in the myocardium may be an artifact rather than pathology, repeat the sequence with the phase-encoding direction swapped. Artifacts move with the phase direction; real pathology stays in place.

Final Checks:

Before finishing a cardiac viability MRI, always check these 6 points to ensure diagnostic quality:

1. Wall Motion and Thickness: Ventricular walls must thicken during systole. Look for areas that move poorly or stay thin. These may be scars.
2. Chamber and Valve Clarity: All four chambers and major valves must be visible, and should open and close smoothly in cine views.
3. Septal and Global Motion: The interventricular septum should move inward with each beat.
4. Stack Coverage: SAX slices must fully cover apex to base. Avoid gaps or missing regions, especially near papillary muscles.
5. Image Quality and Artifacts: Images must have strong SNR, sharp borders, and minimal artifacts.
6. Pericardium and Lung Bases: Check that the pericardium is intact and look for effusions in the black blood image.

These checks help confirm scan success before contrast or treatment decisions.

This completes the planning phase of our cardiac viability MRI protocol focusing on function and morphology.

In Part 2, we'll cover cardiac tissue characterization with perfusion and late gadolinium enhancement sequences to complete the full viability study.