Anatomic Stenosis Severity as a Prognostic Marker in Patients With Low-Flow Low-Gradient Aortic Stenosis Undergoing TAVI

Study Overview
=================
Brief Summary
-----------------
The ATLAS TAVI Registry is a retrospective, investigator-initiated, multicenter registry including patients, who underwent Transcatheter Aortic Valve Implantation (TAVI) for classical or paradoxical low-flow, low-gradient aortic stenosis (LFLG AS) with available non-contrast MSCT data on aortic valve calcification (AVC). The main objective of this study is the assessment of outcome after TAVI according to AVC density severity in patients with LFLG AS.

Detailed Description
-----------------
Aortic valve calcification (AVC) as assessed by MSCT is highly correlated with aortic stenosis (AS) severity and, thus, has become an important tool for diagnosing severe AS, especially in patients with low-flow low-gradient aortic stenosis (LFLG AS). Moreover, in medically treated AS patients AVC is directly associated with poor prognosis. In contrast, the prognostic benefit of eliminating AS by Transcatheter Aortic Valve Implantation (TAVI) in patients with LFLG AS seems to be larger in patients with high AVC density (AVCd) compared to those with low AVCd, at least in classical (low EF) LFLG AS. Hence, we hypothesize that AVCd might be a valuable marker for treatment response among TAVI patients with LFLG AS, who are known to suffer from poor outcome even after elimination of AS. The multicentric ATLAS TAVI Registry of LFLG AS patients, who underwent TAVI, assesses the impact of AVCd on outcome in these patients.

Official Title
-----------------
AnaTomic Stenosis Severity Derived From Computed Tomography as a Prognostic Marker in Patients With Low-flow Low-gradient Aortic Stenosis Undergoing Transcatheter Aortic Valve Implantation

Conditions
-----------------
Low-Flow, Low-Gradient Aortic Stenosis

Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: age ≥18 years patient gave written informed consent for data acquisition and transfer for LFLG AS: -- available non-contrast MSCT data on aortic valve calcification (AVC, Agatston Units) Exclusion Criteria: - LFLG AS without non-contrast MSCT data on AVC

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Classical Low-Flow, Low-Gradient Aortic Stenosis<br>Classical Low-Flow, Low-Gradient Aortic Stenosis is defined as valve area <1 cm2, mean gradient <40 mmHg, ejection fraction <50% and stroke volume index (SVi) ≤35 mL/m2 by resting transthoracic echocardiography. Dobutamine stress echocardiography is not mandatory for the definition of classical LFLG AS. All patients in this subgroup underwent TAVI and have available data on aortic valve calcification. | |
| Paradoxical Low-Flow, Low-Gradient Aortic Stenosis<br>Paradoxical Low-Flow, Low-Gradient Aortic Stenosis is defined as valve area <1 cm2, mean gradient <40 mmHg, ejection fraction ≥50% and SVi ≤35 mL/m2 by resting transthoracic echocardiography. All patients in this subgroup underwent TAVI and have available data on aortic valve calcification. | |
| High-Gradient Aortic Stenosis (Control group)<br>High-Gradient Aortic Stenosis is defined as valve area <1 cm2 and mean gradient >40 mmHg by resting transthoracic echocardiography. All patients in this subgroup underwent TAVI. Data on aortic valve calcification is not mandatory for this control group. | |
| Conservative treatment (Control group)<br>The subgroup includes all patients with (severe or non-severe) aortic stenosis, who underwent conservative treatment. Data on aortic valve calcification is not mandatory for this control group. | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| All-cause mortality |  | 12 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cardiovascular Mortality | Incidence of cardiovascular death, defined as death attributable to myocardial ischemia and infarction, heart failure, cardiac arrest because of other or unknown cause, or cerebrovascular accident. | 12 months | 
| Rehospitalizations for congestive heart failure | Incidence of new-onset or worsening signs and symptoms of heart failure that required urgent therapy and resulted in hospitalization, e.g. as assessed by patient interviews or hospital records. | 12 months | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Aortic Stenosis, Low-Flow, Low-Gradient, TAVI