Flagship 2: Cardiovascular diagnostics and therapeutics

Principal Investigators

Professor Martyn Nash, University of Auckland
Professor Alistair Young, University of Auckland
Professor Geoff Chase, University of Canterbury

Associate Investigators

Dr Vicky Wang, Dr Rob Doughty, Professor Bruce Smaill, Professor Peter Hunter, Dr David Budgett, Dr Jichao Zhao, Dr Jagir Hussan, Dr Geoff Shaw

Summary

Cardiovascular dysfunction (CVD) is a leading cause of death, hospital admission, and reduced quality of life, and costs approximately 1% of New Zealand’s GDP. To reduce the economic and societal costs, we need better ways to estimate and monitor key biomarkers that are not directly measurable - but that can be used to guide CVD patient management in a more reliable and personalised manner.

The overall goal of this Flagship is to develop model-based biomarkers and methods to guide care of CVD patients.

Three main areas of translational research are being addressed:

1. Enhanced Echocardiography for Heart Disease (Echo)

An MRI scan image with mesh imposed on top.This project will develop novel methods for augmenting clinical echocardiographic examinations with statistical population-based heart models and finite element analysis of ventricular mechanics. Existing tools developed for cardiac magnetic resonance imaging (MRI) will be adapted to enable interactive 3D modelling of left ventricular geometry and function directly from Echo imaging, which is cheaper, faster and more widely accessible compared to MRI. The new Echo analysis tools will provide biomarkers of the mechanical status (stiffness, contractility, stress and work load) of the heart. The personalised cardiac analysis framework will be used to analyse data from a variety of CVD patients to characterise the variability of cardiac mechanical and remodelling parameters across patient population groups. This will provide a strategic, long-term pathway by which Echo exams can be used to augment risk assessment as a primary healthcare tool.

2. Interactive Electrophysiology Imaging (EPS)

This project is focused on enabling interactive and intuitive presentation of anatomically registered electrophysiology data to cardiac clinicians for improved interventional treatment of rhythm disturbances, such as persistent atrial fibrillation (PeAF), which is a known risk of stroke and contributes to mortality in congestive heart failure. Current techniques for identifying the functional and anatomic substrates that sustain PeAF are ineffective. We propose to address this using real-time electrophysiological mapping of the atrial chambers.

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A screenshot of a computer software named MITKAtrialMapping. It shows a split window, the left side showing a model, the right side showing waveforms.The objectives are: (i) to project potentials acquired with novel intra-atrial multi-electrode catheters onto the inner atrial surfaces in real-time; (ii) to develop new signal analysis techniques for characterising spatio-temporal waveform complexity in PeAF; and (iii) to validate these methods using large-animal experiments. These pathways will enable high technology solutions to be implemented in the clinical workflow for routine evaluation of patients with CVD. 

3. Real-Time Blood Delivery Sensing For Critical Care and Beyond (RTBS)

This project addresses the lack of direct, real-time, non-invasive measurements of important cardiovascular data in ICU patients. CVD and cardiac surgery comprise 30% of ICU and are the leading causes of ICU admission, cost, and mortality.

All treatment tries to increase the heart’s stroke volume (SV) and the resulting perfusion of organs and peripheral tissues. The RTBS project will develop multiple lumen catheters for use with localised cardiovascular mechanics models to deliver SV in real-time. Peripheral flow, oxygen extraction and thus perfusion will be assessed using a novel pulse oximeter solution that utilises pneumatic constriction to create the first ever non-invasive simultaneous measures of arterial and venous oxygen saturations and local flow, and thus extraction and perfusion.