NCT03363087: HD-SAGA

High Density Scar Guided Atrial Fibrillation Mapping

Completed NA Last updated 18 May 2025

What this trial tests

NA trial testing Mapping and ablation in Atrial Fibrillation in 60 participants. Completed in 1 March 2023.

Timeline

27 August 2019

Primary endpoint
1 March 2023

1 March 2023

Quick facts

Lead sponsor	University Hospital Southampton NHS Foundation Trust
Phase	NA
Status	Completed
Study type	INTERVENTIONAL
Allocation	non randomized
Design	single group
Masking	none
Primary purpose	diagnostic
Enrollment	60
Start date	27 August 2019
Primary completion	1 March 2023
Estimated completion	1 March 2023
Sites	1 location across United Kingdom

Drugs / interventions tested

• Mapping and ablation
• Mapping

Conditions studied

• Atrial Fibrillation — all drugs for Atrial Fibrillation →

Sponsor

University Hospital Southampton NHS Foundation Trust

Who can join

Adults 18 to 90, any sex, with Atrial Fibrillation. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

HD SAGA:

There is increasing evidence that having AF is associated with some scarring of the upper chamber of the heart, the left atrium. There is also evidence that the amount of scarring can predict ablation success rates. Recently, rapid ultra high density mapping equipment has become available and this has the capability of defining the electrical scar in the atrium in detail. The equipment used to do this is standard approved equipment for the procedure but its use for making scar maps has not been fully assessed.

In the mapping phase of the study therefore, the aim will be to collect high density scar maps in AF and normal rhythm to see how they compare. Maps will be collected in different ways to see if that changes their accuracy. The study will also assess if the values previously suggested as representing scar with lower density mapping systems are still appropriate where high density mapping equipment is used. The results from this study will help to improve the understanding of scar in the atrium and help demonstrate the most efficient way to collect scar information using this high density mapping equipment. In the future, clinicians may be able to use these very detailed scar maps to tailor and refine the way they ablate patients with AF, though the focus of the current study is just on collecting the scar information.

While identifying areas requiring ablation is important to an ablation procedure, the other important aspect is the efficacy of ablation. Until now, we have been reliant on assessing our inputs into an ablation (such as the level of contact and the power delivered) but have been limited in the assessment of the output of an ablation in terms of lesion characteristics. New ablation catheter technology is now available which can assess the localised impedance drop with ablation. This is likely a better surrogate for lesion parameters than what we have previously had available and merits further study. Based on such study, we may be able to define targets for ablation which would help to guide future ablations.

HD SAGA S:

Approval amendment March 2021 In addition to the above, using new catheter technology incorporating contact force into the assessment of ablation lesion efficacy.

HD SAGA H:

Approval amendment March 2021 Using new mapping catheter (HD Grid) and algorithms (HD Wave) to compare scar maps between AF and SR and pre-establish pulmonary vein isolation lines.

Publications & conference data

1 peer-reviewed publication reference this trial (live from Europe PMC):

1. Comparison of voltages between atria: differences in sinus rhythm and atrial fibrillation.
   Bates AP, Paisey J, Yue A, Banks P, et al · · 2024 · cited 1× · PMID 37875609 · DOI 10.1007/s10840-023-01671-0