Outcome Prediction in Patients With Aortic Stenosis After TAVI

Study Overview
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Brief Summary
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This study will investigate changes right ventricular function and functional recovery metrics after transcatheter aortic valve implantation

Detailed Description
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Aortic stenosis (AS), is a condition in which the aortic valve becomes narrowed as people get older, causing the heart pump (the left ventricle) to struggle to push blood through it, leading to breathlessness, chest pain and blackouts. If left untreated, the prognosis is bleak (similar to lung cancer). Previously the only effective treatment for AS was a valve replacement via open heart surgery, which was too high risk for many patients to undergo, meaning they were left without treatment. Over the last decade transcatheter aortic valve implantation (TAVI) has emerged as a treatment option for most patients with severe symptomatic AS. In TAVI, a new valve is inserted through a small tube, usually in the leg artery, which avoids open heart surgery. Clinical outcomes after TAVI have significantly improved with the accumulation of operator and institution experience as well as the wide use of newer generation devices. However, a significant minority of patients undergoing TAVI derive little or no benefit from the procedure. Nearly a third describe no improvement in quality of life, or die within the first year. To combat this problem, it is essential we develop more sophisticated means of predicting adverse outcomes related to TAVI, to improve the selection of patients and identify patients where the potential benefit of the procedure is outweighed by unfavourable outcomes. Assessment of physical recovery and improvement of symptoms and quality of life after TAVI is an important aspect of examining the outcomes of treatment. This is often a more meaningful and relevant treatment goal in the TAVI cohort than 'hard' clinical outcomes (like death and stroke) alone. Traditionally, less emphasis has been put on the assessment of the right side of the heart (the right ventricle) in evaluating physical recovery after TAVI. We propose prospective observational study to evaluate the significance of the right side of the heart on the clinical outcomes related to functional recovery in patients undergoing TAVI.

Official Title
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Observational Study of Outcome Prediction in Patients Undergoing Transcatheter Aortic Valve Implantation (TAVI) for Severe Symptomatic Aortic Stenosis (PREDICT-TAVI).

Conditions
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Aortic Stenosis, Severe

Intervention / Treatment
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* Procedure: Transcatheter aortic valve implantation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with symptomatic severe aortic stenosis (AVA <1.0 cm2/<0.6cm2/m2 or mean gradient >40mmHg or jet velocity >4.0 m/s). Exclusion Criteria: Extracardiac limitations of ambulatory exercise, cardiac rehab opt out, non-transfemoral TAVI, haemodynamic instability/cardiogenic shock, LVEF <40%, poorly controlled AF, severe COPD, primary pulmonary hypertension, evidence of cardiac amyloid, more than moderate concomitant valvular heart disease other than aortic stenosis, previous sternotomy, permanent pacemaker implant, patients enrolled in another study where participation would involve deviation from either protocol.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Severe aortic stenosis<br>Aortic valve area <1.0 cm2/<0.6cm2/m2 or mean gradient >40mmHg or jet velocity >4.0 m/s. | Procedure: Transcatheter aortic valve implantation<br>* Intervention on aortic valve for severe aortic stenosis<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in TAPSE/PASP coupling measure | RV-PA coupling is measured using ratio of TAPSE/PASP on transthoracic echocardiography. | Baseline to immediately following intervention and 3 months follow up | 
| Change in daily accelerometer measured activity (steps) | Recorded on a wrist-worn accelerometer continuously for 14 days. | Baseline to 3 months follow up | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in New York Heart Association (NYHA) Functional Class | The New York Heart Association (NYHA) Classification provides a simple way of classifying the extent of heart failure. It classifies patients in one of four categories based on their limitations during physical activity: Class I - No symptoms and no limitation in ordinary physical activity Class II - Mild symptoms (mild shortness of breath and/or angina) and slight limitation during ordinary activity. Class III - Marked limitation in activity due to symptoms Class IV - Severe limitations. | Baseline to 3 months follow up | 
| Change in N-terminal Prohormone of Brain Natriuretic Peptide (NT-proBNP Levels) | Biomarker of myocardial strain | Baseline to 3 months follow up | 
| Change in right ventricular efficiency as measured by ventricular arterial coupling | VA coupling is calculated by the ratio of effective arterial elastance (Ea), a measure of afterload, to LV end systolic elastance (Ees), a relatively load independent measure of LV chamber performance. Both these measures are expressed in mmHg/ml and as continuous variables. | Baseline to immediately following intervention | 
| Change in right ventricular strain/PASP coupling measure | RV-PA coupling can be measured using ratio of right ventricular strain/PASP on transthoracic echocardiography. | Baseline to immediately following intervention and 3 months follow up | 
| Change in right ventricular end-systolic volume/stroke volume coupling measure | RV-PA coupling can be measured using ratio of right ventricular ESV/SV on transthoracic echocardiography. | Baseline to immediately following intervention and 3 months follow up | 
| Change in right ventricular ejection fraction/PASP coupling measure | RV-PA coupling can be measured using ratio of right ventricular EF/PASP on transthoracic echocardiography. | Baseline to immediately following intervention and 3 months follow up | 
| Change in right ventricular S'/PASP coupling measure | RV-PA coupling can be measured using ratio of S'/PASP on transthoracic echocardiography. | Baseline to immediately following intervention and 3 months follow up | 
| Change in Six Minute Walk Test (6MWT Distance or 6MWD) | The Six Minute Walk Test (6MWT) is a practical simple test that requires a 100-ft hallway but no exercise equipment or advanced training for technicians. This test measures the distance that a patient can quickly walk ona flat, hard surface in a period of 6 minutes (the 6MWD). It evaluates the global and integrated responses of all the systems involved during exercise, including the pulmonary and cardiovascular systems, systemic circulation,peripheral circulation, blood, neuromuscular units, and muscle metabolism. It does not provide specific information on the function of each of the different organs and systems involved in exercise or the mechanism of exercise limitation, as is possible with maximal cardiopulmonary exercise testing. The self-paced 6MWT assesses the submaximal level of functional capacity. | Baseline to 3 months follow up | 
| Change in Quality of Life (QoL) as Measured by the Kansas City Cardiomyopathy Questionnaire (KCCQ) | The Kansas City Cardiomyopathy Questionnaire is a 23-item, self administered instrument that quantifies physical function, symptoms, social function, self-efficacy and knowledge, and quality of life. with a range of possible subscale scores from 0 to 100, with 100 representing the least burden of symptoms. The KCCQ tool quantifies the following six (6) distinct domains and two (2) summary scores: KCCQ Symptom Domain, KCCQ Physical Function Domain, KCCQ Quality of Life Domain, KCCQ Social Limitation Domain, KCCQ Self-efficacy Domain, KCCQ Symptom Stability Domain, Clinical Summary Score and Overall Summary Score. Clinical Summary Score includes total symptom and physical function scores to correspond with NYHA Classification. Overall Summary Score includes the total symptom, physical function, social limitations and quality of life scores. | Baseline to 3 months follow up |