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DASI Dimensions is a standalone, non-invasive, clinical decision support software solution that is intended for use by cardiologists and radiologists in context of the aortic stenosis population.

DASI Dimensions provides the end-user with pre-defined images and measurements (diameters, lengths, angles, areas, and perimeters) of cardiovascular structures.

The clinician receiving the results the responsibility for interpreting and validating all information and making all patient treatment decisions.

DASI Dimensions is not intended to replace the clinician's decision or device's instructions for use.

DASI Dimensions is prescription use only.

DASI Dimensions is an image post-processing software system intended for clinical decision support in the context of pre-procedural planning of Transcatheter Aortic Valve Replacement (TAVR) procedures. The software provides users with a report of generated dimensions of cardiac structures. DASI Dimensions software is not operated by physicians.

DASI Dimensions is an off-site software system that receives cardiologists input via upload of patient multiphase DICOM computed tomography angiography (CTA) chest image files through DASI Simulations web portal. The processed report is then available for viewing and downloading. The report is generated using proprietary algorithms that (a) detect key aortic root control points with the assistance of a static deep learning artificial intelligence (Al) model and (b) calculate anatomical measurements relevant for pre-TAVR evaluation. DASI Simulations engineers perform quality checks at both steps before releasing the report to the end user via the portal.

DASI Dimensions does not contact with the patient, nor does it control any life sustaining devices. The information provided by DASI Dimensions is not diagnostic, nor does it determine recommended medical care.

The cardiologists and/or radiologists receiving the responsibility for interpreting and validating all information and making all patient treatment decisions.

DASI Dimensions:

· Supports quantification of cardiac structures for pre-procedural planning of aotic stenosis patients in consideration for potential TAVR procedures.

· Provides the measurement of different structures of the heart, e.g., aortic root, aortic valve.

The DASI Dimensions (V1.0) device's acceptance criteria and the study proving it meets these criteria are outlined below.

1. Table of Acceptance Criteria and Reported Device Performance

2. Sample Size Used for the Test Set and Data Provenance

• AI Control Point Detection Validation Study: The document does not specify the exact sample size for the "testing dataset" used in this study, only mentions "All testing, validation, and training cases were independent of each other."
• Automatic Measurements Validation Study: The document doesn't specify the sample size used for this study.
• Performance Validation Study (TP134 and TR134): Cohort of patient CT images (n=40).
• Operator Variability Study (TP136 and TR136): Dataset of CTAs (n=14).
• Control Point Sensitivity Study (TP140 and TR140): Dataset of CTAs (n=14).

Data Provenance:
"Relevant studies incorporated data with various distributions of ethnicity, gender, and age. All data was collected through the DASI Simulations secure server, AWS, through internal workstations operated by trained DASI Dimensions operators." The document implies these were retrospective data collected from clinical operations rather than prospective trials, as it explicitly states, "No prospective clinical trials were conducted in support of this Traditional 510(k)." The country of origin for the data is not explicitly stated.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

• Number of Experts: "The reference standard was derived from 2 qualified truthers each CTA, whose measurements were averaged for each case."
• Qualifications of Experts: They are described as "qualified truthers" and "qualified DASI Dimensions operators (ground truth)" or "clinicians." Specific details like years of experience or board certification (e.g., radiologist, cardiologist) are not provided, but the context of "manual control points generated by qualified DASI Dimensions operators" suggests they are trained personnel in using such software and interpreting medical images.

4. Adjudication Method for the Test Set

• Adjudication Method: "If there was a significant variance between the initial two truthers, an adjudicator was involved." This indicates a 2+1 adjudication method.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done

No, a multi-reader multi-case (MRMC) comparative effectiveness study explicitly comparing human readers with and without AI assistance was not conducted. The studies focused on validating the device's measurements against ground truth established by human experts or the variability between operators using the device. The document explicitly states: "No prospective clinical trials were conducted in support of this Traditional 510(k)."

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done

Yes, standalone performance was evaluated, particularly for the AI model:

• AI Control Point Detection Validation Study: "In the AI testing dataset the AI generated control points were compared to manual control points generated by qualified DASI Dimensions operators (ground truth)." This indicates a standalone evaluation of the AI's ability to detect control points.
• Automatic Measurements Validation Study: This study compared the "automatic measurement outputs generated using control points" (which were presumably AI-generated or system-computed) to manual measurements by clinicians. This also reflects a standalone assessment of the automated measurement capabilities.

It's important to note that the device's overall workflow involves "DASI Simulations engineers perform quality checks at both steps before releasing the report to the end user," and it is described as a "semi-automatic AI enhanced workflow." However, the validation studies described, particularly the AI Control Point Detection and Automatic Measurements, evaluate the software's automated functionalities independently against a human-established ground truth.

7. The Type of Ground Truth Used

The ground truth used was expert consensus / expert manual measurements.

• "The reference standard was derived from 2 qualified truthers each CTA, whose measurements were averaged for each case. If there was a significant variance between the initial two truthers, an adjudicator was involved."
• "Al generated control points were compared to manual control points generated by qualified DASI Dimensions operators (ground truth)."
• "Automatic measurement outputs ... compared to the measurements generated manually by clinicians using current standard of care methods."
• "Outputs were compared to qualified clinician truther generated control points."

8. The Sample Size for the Training Set

The document mentions "training, validation, and testing datasets" for the AI model (W112 and TR132) but does not explicitly state the sample size for the training set. It only clarifies that, "All testing, validation, and training cases were independent of each other and were not used in any other validation studies."

9. How the Ground Truth for the Training Set Was Established

The document does not explicitly describe how the ground truth for the training set was established, but it is highly probable that it was established using a similar method to the test set, i.e., through qualified human experts (truthers/operators/clinicians) making manual annotations and measurements, potentially with adjudication for discrepancies. This is inferred from the overall approach to ground truth described for the validation studies, where human expert input is consistently used as the reference standard.

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PrecisionTAVI is an optional, non-invasive, post processing software solution that is indicated for patient-specific simulations of Transcatheter Aortic Valve Replacement (TAVR) during procedural planning.

The software performs computer simulation to predict post TAVR in vivo valve frame deformation of clinician selected Transcatheter Heart Valve (THV) device types and sizes.

The information provided by PrecisionTAVI is intended for use by cardiologists, and clinical specialists, and is not intended in any way to eliminate, replace, or substitute for, in part, the healthcare provider's judgment and analysis of the patient's condition receiving the images retains the responsibility for interpreting and validating all information and making all patient treatment decisions.

PrecisionTAVI is not intended to replace the simulated device's instructions for use for final TAVR device selection and placement.

DASI Simulations PrecisionTAVI is a computer simulation device that predicts implant frame deformation after implantation of a Transcatheter Heart Valve (THV) device. The simulation combines a predefined THV device model and size with a patient-specific model of the patient's anatomy thereby predicting the post deployment deformation of the THV and the anatomy. The simulation results are intended to be used by qualified clinicians as additional information for planning transcatheter aortic valve replacement (TAVR).

PrecisionTAVI conducts TAVR device deployment simulation using proprietary computational modeling technology.

The input for the simulation is a 3D model of the patient anatomy. The 3D model is generated from 2D medical images of the patient anatomy (multi-slice Cardiac Computed Tomography).

The simulation output is a report with 3D visualization capability to depict the predicted deformed THV in the deformed patient-specific anatomy of the aortic valve and root.

The 3D model generation and the report generation from the simulation is performed by trained operators at DASI Simulations using an established workflow. The report is accessible to the end user as a download from the DASI Simulations portal with a standard web browser.

Here is a summary of the acceptance criteria and the study proving the device meets those criteria, based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance

2. Sample Size Used for the Test Set and Data Provenance

• Sample Size: 89 patients.
• Data Provenance: The data was derived from clinical deployments. Patients had tricuspid aortic valve morphology, received a SAPIEN S3/Ultra THV, and had both pre-TAVR and post-TAVR CT imaging available. The specific country of origin is not explicitly stated, but it's implied to be clinical data. It is retrospective as it uses pre-existing clinical deployment data (pre-TAVR and post-TAVR CT images).

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

• Number of Experts:
  • Quantitative Ground Truth: No external experts were used; ground truth was established by reconstructing THV geometries directly from post-operative clinical CT image data.
  • Qualitative Ground Truth:
    • Five (5) experienced independent clinicians in the TAVR space.
    • Three (3) trained DASI Simulations engineers.
• Qualifications of Experts:
  • Clinicians: "Experienced independent clinicians in the TAVR space." (Specific years of experience or other detailed qualifications not provided).
  • Engineers: "Trained DASI Simulations engineers." (Specific qualifications not provided beyond being "trained").

4. Adjudication Method for the Test Set

• Quantitative: Not applicable, as ground truth was derived directly from post-operative clinical CT images for quantitative measurements.
• Qualitative: Not explicitly stated as a formal adjudication method like '2+1' or '3+1'. However, clinicians and engineers were individually presented with comparison image pairs and asked to state if they found the simulated outputs to be "in close agreement" with the clinical outputs. The overall percentage of agreement was then reported. It does not appear there was a consensus or tie-breaking process explicitly described for individual cases, but rather an aggregate assessment of agreement.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

• No, a MRMC comparative effectiveness study was not reported. The study focused on the performance of the AI device itself (standalone and qualitative assessment), not on how human readers improved with or without AI assistance.

6. Standalone Performance Study

• Yes, a standalone performance study was done.
  • Quantitative Validation: The device's predicted THV deformation (diameter and aspect ratio) was compared directly against measurements derived from post-TAVR CT images.
  • Qualitative Validation: Clinicians and engineers assessed the "close agreement" between the device's simulated outputs and clinical post-procedural images. Both of these are examples of standalone performance evaluation.

7. Type of Ground Truth Used

• Quantitative Validation: The ground truth for quantitative measurements (THV diameter and aspect ratio) was derived from post-operative clinical CT image data. This is essentially "outcomes data" in the sense that it represents the actual, measured post-TAVR state in patients.
• Qualitative Validation: The ground truth for qualitative assessments was also the post-operative clinical images (clinical outputs), against which the simulated outputs were compared by clinicians and engineers.

8. Sample Size for the Training Set

• The document does not provide information regarding the sample size for the training set. It only mentions the test set of 89 patients.

9. How the Ground Truth for the Training Set Was Established

• As the training set sample size is not provided, the method for establishing its ground truth is also not specified in the document.

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