Validation of a Novel, Non-Dimensional Approach for Estimation of Pressure Gradients in Aortic Stenosis (AVD-PowerLaw)

Entscheidungsunterstützung Bei Herzklappenerkrankungen Anhand Funktionaler Und Morphologischer Eigenschaften Mittels Methoden Der Mathematischen Modellierung Und Des Maschinellen Lernens

A novel, image-based model for estimation of the pressure gradient across stenosed aortic valves is compared against invasively measured pressure gradients from clinical routine.

Study Overview

• Status: Unknown
• Conditions: Aortic Valve Stenosis
• Intervention / Treatment: Procedure: TAVI

Detailed Description

Using temporally resolved computed tomography images, the patient-specific geometry of the stenosed aortic valve during peak systole is reconstructed. Using this geometry, the projected area of the aortic valve's orifice (AVA) is calculated. Additionally, the left ventricular geometry is reconstructed for the complete heart cycle. Using the information of the left ventricular volume change, the patient-specific flow profile and peak-systolic flow (Q)is calculated. Using this information, the pressure gradient is calculated using a power law estimation of the form PG = a * AVA^b * Q^c. The model generation and parameter fit is described in [1].

To validate this model, retrospective data of patients receiving a catheter-based replacement of the aortic valve (TAVI) is collected. For those patients, CT images are already acquired for treatment planning and the invasive pressure measurements are performed during replacement of the aortic valve. Therefore, no additionally steps are required. Using the CT images the patient-specific aortic valve area ad flow rate are calculated. This information is then used for estimation of the pressure gradient using the power law model. The catheter-based pressure gradient is calculated as the difference between the peak-systolic pressure in the left ventricle and the ascending aorta before implantation of the prosthesis.

[1] Franke et al.; Towards improving the accuracy of aortic transvalvular pressure gradients: rethinking Bernoulli; Medical & Biological Engineering & Computing (2020); https://doi.org/10.1007/s11517-020-02186-w

• Study Type: Observational
• Enrollment (Anticipated): 200

Contacts and Locations

• Study Contact: Name: Titus Kühne, Prof. Dr.; Phone Number: +49 30 4593 2078; Email: titus.kuehne@dhzb.de

Study Locations

• Germany
  • Deutschland
    • Berlin, Deutschland, Germany, 13353
      • Recruiting
      • Deutsches Herzzemtrum Berlin
      • Contact: Titus Kühne, Prof. Dr.; Phone Number: +49 30 4593 2078; Email: titus.kuehne@dhzb.de

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

- retrospective acquisition of patients that receive TAVI

Description

Inclusion Criteria:

• aortic valve stenosis
• treatment via TAVI

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Only
• Time Perspectives: Retrospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
AVD Patients; Patients suffering from aortic valve stenosis receiving replacement of the diseased valve using a TAVI procedure.	Procedure: TAVI; Replacement of the aortic valve using a biological prosthesis that is inserted via a catheter.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
predicted vs. cather-measured pressure gradient across the aortic valv	1 week up to 1 year

Collaborators and Investigators

• Sponsor: German Heart Institute
• Collaborators: Charite University, Berlin, Germany

Study record dates

Study Major Dates

• Study Start (Actual): October 28, 2019
• Primary Completion (Anticipated): December 31, 2020
• Study Completion (Anticipated): June 30, 2021

Study Registration Dates

• First Submitted: October 19, 2020
• First Submitted That Met QC Criteria: October 19, 2020
• First Posted (Actual): October 23, 2020

Study Record Updates

• Last Update Posted (Actual): October 23, 2020
• Last Update Submitted That Met QC Criteria: October 19, 2020
• Last Verified: October 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Heart Diseases; Cardiovascular Diseases; Pathological Conditions, Anatomical; Aortic Valve Disease; Heart Valve Diseases; Ventricular Outflow Obstruction; Aortic Valve Stenosis; Constriction, Pathologic
• Other Study ID Numbers: AVD-PowerLaw

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No