Clinical trial NCT04827238: Standardized Invasive Hemodynamics for Elevated Gradients Post TAVR (DISCORDANCE TAVR)
Official title: Standardized Invasive Hemodynamics for Monitoring Acute and Long Term Valve Performance in Patients With Elevated Gradients Post Transcatheter Aortic Valve Replacement
Study type: OBSERVATIONAL
Overall status: UNKNOWN
Conditions: Aortic Stenosis
Aortic Valve Stenosis
Lead sponsor: University of British Columbia
Sponsor class: OTHER
Collaborators: name: Edwards Lifesciences
First posted: 2021-04-01
Enrollment: 50
Sex: ALL
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: OTHER
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients \> 1 month post-transcatheter aortic valve replacement

Brief summary: The DISCORDANCE TAVR study will determine the discordance between echocardiography-derived and invasive transaortic gradients, as determined by a consistent and reproducible technique (Standardized Invasive Hemodynamics) post-TAVR.

Detailed description: Since the introduction of Doppler echocardiography, non-invasive estimation of aortic valve gradients through modification and simplification of the Bernoulli equation and derivation of the AVA, via the continuity equation, have become the primary method to assess the severity of AS.

The utility of echocardiography to successfully determine aortic valve gradients and AVA has been established in the presence of AS, and such observations have been extrapolated to prosthetic valves. However, several reports following SAVR and TAVR for both native and valve-in-valve have demonstrated significant discordance between echocardiography-derived and direct invasive measurements of aortic valve mean gradients.

The indexed AVA (iAVA) is derived from the stroke volume indexed to the BSA. The stroke volume index (SVI) divided by the Doppler velocity time integral of the continuous wave aortic valve spectral profile, is used to determine the presence of severe PPM. As such, a low iAVA may occur due to a low flow state defined by a reduced SVI (\<35 ml/m2) or a reduced stroke flow rate (\< 200 ml/second) and calculated by dividing the SV by the ejection time spuriously increasing the incidence of severe PPM. A low indexed effective orifice area due to a low SVI, in the absence of intrinsic PPM, has been referred to as "pseudo-severe PPM", but the impact of flow state on PPM has not been described.

Nonetheless, echocardiographic thresholds for the evaluation of prosthetic valve performance after TAVR have been widely adopted: mean-gradient \> 20mmHg, severe PPM as defined by an iAVA \< 0.65 cm2/m2, and AR, including paravalvular and transvalvular AR of moderate or greater severity. These criteria are suggested to indicate procedural success and predict long-term clinical outcomes (12). Practically many centers utilize an echocardiography-derived mean gradient for the follow-up of transcatheter heart valves. While the association of at least moderate paravalvular AR with mortality has been consistently demonstrated, there remains uncertainty regarding the clinical impact of severe PPM as determined by index echocardiography. Furthermore, the magnitude of discordance between echocardiography-derived and invasive aortic valve mean-gradients post TAVR is unknown and it remains unclear how to reconcile measurement discordances in clinical practice. These potential differences may have an important impact on patient management post TAVR.

The DISCORDANCE TAVR study will determine the discordance between echocardiography-derived and invasive transaortic gradients, as determined by a consistent and reproducible technique (Standardized Invasive Hemodynamics) post-TAVR.

Eligibility criteria: Inclusion Criteria:

* Echocardiographic transaortic mean gradient ≥ 20mmHg OR VARC-3 criteria for ≥ moderate hemodynamic valve deterioration post TAVR on any TTE \> 1 month post-TAVR
* Consensus by the Heart Team that the patient is suitable for Standardized Invasive Hemodynamics (SIH).

Exclusion Criteria:

* CT demonstrating leaflet thrombosis or hypoattenuated leaflet thickening (HALT)

Primary outcomes:
measure: Transaortic valve gradients
timeFrame: 30 days
measure: Transaortic mean gradient reclassification
timeFrame: 30 days
measure: VARC-3 hemodynamic valve deterioration reclassification
timeFrame: 30 days
measure: Patient-Prosthesis Mismatch (PPM) reclassification
timeFrame: 30 days
Secondary outcomes:
measure: Total procedure time
timeFrame: 30 days
measure: Risks of procedural complications
timeFrame: 30 days
Other outcomes:
Locations:
city: Tucson
country: United States
facility: PIMA Heart Centre
state: Arizona
city: Boca Raton
country: United States
facility: Tenet Health
state: Florida
city: Indianapolis
country: United States
facility: eCommunity
state: Indiana
city: Munster
country: United States
facility: Community Hospital
state: Indiana
city: Boston
country: United States
facility: Massachusetts General Hospital
state: Massachusetts
city: Southfield
country: United States
facility: William Beaumont Hospital
state: Michigan
city: Dallas
country: United States
facility: Baylor Scott & White
state: Texas
city: Vancouver
country: Canada
facility: Vancouver General Hospital
state: British Columbia
city: Vancouver
country: Canada
facility: St. Paul's Hospital
state: British Columbia
city: Hamilton
country: Canada
facility: McMaster University
state: Ontario
Study officials:
affiliation: University of British Columbia
name: David Wood, MD
role: PRINCIPAL_INVESTIGATOR
References: