Trans-catheter aortic valve replacement versus conventional aortic valve surgery: A detailed echocardiographic study of novel cardiac structural parameters and functional cardiac mechanics

Project summary

The project will study detailed aspects of cardiac function pre and post both traditional surgical aortic valve replacement or a newer, non-surgical technique, transcatheter aortic valve replacement. Novel echocardiographic techniques will be employed to assess for these changes. The project will also outline the effectiveness of an echocardiography core lab during a multi-centre national clinical trial.

Project aims and objectives

Symptomatic patients with severe aortic stenosis (AS) who do not undergo surgical aortic valve replacement (AVR) have poor prognosis with expected 1 year mortality of around 30-50%. Technological advances have resulted in the development of a trans-catheter aortic valve replacement technique (TAVI) to minimise surgical risk in selected patients deemed unsuitable for conventional surgery. However, more recently, it has been suggested that this technique can be used as a potential alternative to surgical AVR. There is strong data showing that TAVI is superior to medical palliation in patients who are surgically rejected for AVR but despite increasing use worldwide, no clinical evidence to support the use of TAVI against current standard treatment – AVR. This current study will collect detailed echocardiographic data from a national randomised controlled clinical trial designed to compare outcomes from traditional AVR when compared to TAVI over a follow-up period of 2 years. As such, novel parameters relating to cardiac structure and functional mechanics will be measured to ascertain previously unstudied prospective changes in cardiac performance pre and post both surgical and transcatheter valve replacement strategies.

This study is multi-centre and echocardiographic images are collected by clinical teams deemed suitable for study inclusion against a strict entry criteria. All detailed echocardiographic analysis procedures are to be performed ‘blinded’ initially and then compared between approaches and against fixed time-points from baseline to two years post procedure. Quality assurance data is to be collected as part of the research process and is to be used to publish novel insights into echocardiographic core lab performance.

The aims of the study are:
1.To measure detailed aspects of cardiac structure, function and mechanics pre and post TAVI and surgical AVR, assessing for any within or between technique interaction.
2.To assess the observed changes in novel, detailed cardiac functional parameters in response to conventional AVR or the newer TAVI approach.
3.To use detailed quality assurance techniques to assess the effective running of a unique national echocardiography core-lab.
4.To develop a European framework for the effective running of an echocardiographic core-lab used as part of multi-centre clinical trials.

Specific requirements of the project

Candidates should have a good undergraduate degree and ideally masters level qualification in the physiological or clinical sciences. Undergraduate / postgraduate qualifications with significant physiology content may also be considered (e.g. sport and exercise science, health science).

Candidates should ideally possess knowledge of echocardiography and also the broader area of Cardiology including diagnostic evaluation, treatment and follow-up of patients with severe valve disease. Knowledge of the NHS and NHS research processes would also be beneficial.

Candidates would ideally have experience of performing and / or interpreting echocardiograms in patients with significant valve disease. However, this is not essential as the analyses techniques required can be learned as part of the PhD program. Previous research within the NHS or in collaboration with NHS partners would be advantageous, together with previous research or work with a patient population.