TAVR Aortic Root Measurements

Purpose

Automate aortic root and cardiac measurements for transcatheter aortic valve replacement (TAVR) necessary to determine the size and type of valve best for the patient.

Tag(s)

 

Panel

 Cardiac

TOUCH-AI ID

 TAI-04180023

Originator

Kimberly Brockenbrough

Panel Chair

Carlo De Cecco

Panel Reviewers

Cardiac Panel

License

Creative Commons 4.0

Status Public Commenting

Clinical Implementation


Value Proposition

Measurements of the aortic root are essential for determining the appropriate size of a prosthetic aortic valve. Inappropriate sizing can result in aortic rupture or perivalvular leak. These measurements are now performed by radiologists and/or a dedicated 3D lab. Obtaining these measurements is time consuming, with times ranging from 45 to 90 minutes. Gated CT angiography (CTA) of the chest is the best method for obtaining the images.

Narrative(s)

An 83-year-old woman presents with dyspnea and increased exercise intolerance. An echocardiogram shows that she has severe aortic stenosis. The patient is determined to be a high-risk candidate for surgery. A CTA of the chest, abdomen, and pelvis is performed to determine the size of the aortic root and determine the best access for deployment of an aortic valve.

Workflow Description

A patient receives ECG-synchronized CTA of the chest. An algorithm retrieves input for an imaging data set and relevant electronic medical record data, including age, gender, and body surface area (BSA; mL/m2). The algorithm determines the best single diastolic and single systolic phases of CT with the least motion artifact and then performs measurements, defined below, on both diastolic and systolic phases. At the aortic annulus, the algorithm measures the minimum and maximum diameters and the area and perimeter. At the maximum diameter of the sinuses of Valsalva, the algorithm measures the minimum and maximum diameters and the area and perimeter. At 15 mm above the annulus at the sinuses of Valsalva, the algorithm measures the minimum and maximum diameters and the area and perimeter. At the sinotubular junction, the algorithm measures the minimum and maximum diameter. The algorithm determines the coronary heights of the right coronary and left main coronary arteries. The algorithm also determines the sinotubular height, calculates the calcium score of the aortic valve, determines the best angle of entry, and determines if the thoracic aorta is aneurysmal based on the gender, BSA, and age of the patient. The algorithm returns all measurements and recommends valve size for the patient for each available vendor.

Considerations for Dataset Development


Procedures(s): Gated CTA of the chest

View(s): CCTA: Any volumetric imaging data set

 

Sex at Birth: {Male, Female}

 

Age: [18,70]

 

History: Severe Aortic stenosis

 

CT: Must be gated with multiple diastolic and systolic phases of the cardiac cycle

 

Contrast Material: {CT w/ IV arterial-phase contrast, w/o arterial-phase contrast}

 

Position: {Weight bearing, nonweight bearing}

Technical Specifications


Inputs

DICOM Study

Procedure

Gated CTA, Chest

Views

CCTA: Any volumetric imaging data set

Data Type

DICOM

Modality

CTA

Body Region

Chest

Anatomic Focus

Heart

 

Primary Outputs

Best Systolic Phase

RadElementID

RDE321

Definition

Systolic phase with the least motion artifact

Data Type

Numeric

Value Set

[0,100]

Units

Percentage of cardiac cycle in systole

 

Best Diastolic Phase

RadElementID

RDE322

Definition

Diastolic phase with the least motion artifact

Data Type

Numeric

Value Set

[0,100]

Units

Percentage of cardiac cycle in diastole

 

Aortic Annulus Maximum Diameter in Systole

RadElementID

RDE323

Definition

Aortic annulus maximum diameter

Data Type

Numeric

Value Set

 

Units

mm

 

Aortic Annulus Minimum Diameter in Systole

RadElementID

RDE324

Definition

Aortic annulus minimum diameter

Data Type

Numeric

Value Set

 

Units

mm

 

Aortic Annulus Perimeter in Systole

RadElementID

RDE325

Definition

Aortic annulus perimeter

Data Type

Numeric

Value Set

 

Units

mm

 

Aortic Annulus Area

RadElementID

RDE326

Definition

Aortic annulus area

Data Type

Numeric

Value Set

 

Units

mm2

 

LVOT 3 mm Below the Annulus Minimum Diameter in Systole

RadElementID

RDE327

Definition

Left ventricular outflow tract (LVOT) 3 mm below the annulus minimum diameter

Data Type

Numeric

Value Set

 

Units

mm

 

LVOT 3 mm Below the Annulus Maximum Diameter in Systole

RadElementID

RDE328

Definition

Left ventricular outflow tract (LVOT) 3 mm below the annulus maximum diameter

Data Type

Numeric

Value Set

 

Units

mm

 

LVOT 3 mm Below the Annulus Perimeter in Systole

RadElementID

RDE329

Definition

Left ventricular outflow tract (LVOT) 3 mm below the annulus perimeter

Data Type

Numeric

Value Set

 

Units

mm

 

LVOT 3 mm Below the Annulus Area in Systole

RadElementID

RDE330

Definition

Left ventricular outflow tract (LVOT) 3 mm below the annulus area

Data Type

Numeric

Value Set

Units

mm2

 

Aortic Annulus Maximum Diameter in Diastole

RadElementID

<not yet defined>

Definition

Aortic annulus maximum diameter

Data Type

Numeric

Value Set

 

Units

mm

 

Aortic Annulus Minimum Diameter in Diastole

RadElementID

<not yet defined>

Definition

Aortic annulus minimum diameter

Data Type

Numeric

Value Set

 

Units

mm

Aortic Annulus Perimeter in Diastole

RadElementID

<not yet defined>

Definition

Aortic annulus perimeter

Data Type

Numeric

Value Set

 

Units

mm

Aortic Annulus Area in Diastole

RadElementID

<not yet defined>

Definition

Aortic annulus area

Data Type

Numeric

Value Set

 

Units

mm2

 

LVOT 3 mm Below the Annulus Minimum Diameter in Diastole

RadElementID

<not yet defined>

Definition

Left ventricular outflow tract (LVOT) 3 mm below the annulus minimum diameter

Data Type

Numeric

Value Set

 

Units

mm

 

LVOT 3 mm Below the Annulus Maximum Diameter in Diastole

RadElementID

<not yet defined>

Definition

Left ventricular outflow tract (LVOT) 3 mm below the annulus maximum diameter

Data Type

Numeric

Value Set

 

Units

mm

 

LVOT 3 mm Below the Annulus Perimeter in Diastole

RadElementID

<not yet defined>

Definition

Left ventricular outflow tract (LVOT) 3 mm below the annulus perimeter

Data Type

Numeric

Value Set

 

Units

mm

 

LVOT 3 mm Below the Annulus Area in Diastole

RadElementID

<not yet defined>

Definition

Left ventricular outflow tract (LVOT) 3 mm below the annulus area

Data Type

Numeric

Value Set

 

Units

mm2

 

Sinotubular Junction Minimum Diameter in Systole

RadElementID

RDE331

Definition

Sinotubular junction minimum diameter

Data Type

Numeric

Value Set

 

Units

mm

 

Sinotubular Junction Maximum Diameter in Diastole

RadElementID

RDE332

Definition

Sinotubular junction maximum diameter

Data Type

Numeric

Value Set

 

Units

mm

 

Right Coronary Height Minimum

RadElementID

RDE333

Definition

Height from aortic annulus to bottom of the right coronary artery origin

Data Type

Numeric

Value Set

 

Units

mm

 

Right Coronary Height Maximum

RadElementID

RDE334

Definition

Height from aortic annulus to top of the right coronary artery origin

Data Type

Numeric

Value Set

 

Units

mm

 

Left Coronary Height Minimum

RadElementID

RDE335

Definition

Height from aortic annulus to bottom of the left coronary artery origin

Data Type

Numeric

Value Set

 

Units

mm

 

Left Coronary Height Maximum

RadElementID

RDE336

Definition

Height from the aortic annulus to the top of the left coronary artery origin

Data Type

Numeric

Value Set

 

Units

mm

 

Aortic Valve Calcium Score

RadElementID

RDE337

Definition

Agatston calcium score of aortic valve

Data Type

Numeric

Value Set

 

Units

Agatston score

Secondary Outputs

AV Angle in Systole

RadElementID

RDE338

Definition

Aortic valve angle

Data Type

Numeric

Value Set

 

Units

degrees

 

Annulus to Apex Curved Length

RadElementID

RDE339

Definition

Distance from aortic annulus to apex of the left ventricle curved in ventricle

Data Type

Numeric

Value Set

 

Units

mm

 

Annulus to Apex Straight Length in Systole

RadElementID

RDE340

Definition

Distance from aortic annulus to apex of the left ventricle with a straight line

Data Type

Numeric

Value Set

 

Units

mm

 

Left Ventricle Width in Systole

RadElementID

RDE341

Definition

Width of left ventricle in systole

Data Type

Numeric

Value Set

 

Units

mm

 

Approximate Deployment Angle

RadElementID

RDE342

Definition

Angle to optimize visualization of the 3 cusps of the aortic valve

Data Type

Numeric

Value Set

 

Units

degrees

Public Commenting


Use cases are meant to be a primary vehicle for distributing clinical information to the developer community. They pinpoint precise scenarios within radiology workflows where potential automation could add noticeable value and establish standards for interpreting and passing corresponding common data elements. Implementing effective standards requires the perspective from all stakeholders. So to that end, we encourage your feedback on use cases.

To submit comments, please email DSIUseCases@acr.org with the use case title(s) and relevant comments by January 1, 2019. If more convenient, you may also download this use case and comment directly on the PDF. Just attach the PDF copy on the email.