Circumvenous Ablation For Treatment Of Atrial Fibrillation
Funder
National Health and Medical Research Council
Funding Amount
$341,844.00
Summary
Atrial fibrillation is the most common abnormal heart rhythm. It causes symptoms that may be disabling but also increases the risk of stroke and death. The lifetime risk of developing atrial fibrillation is 20-25%. Treatment with medications is often unsuccessful and is never curative. Recently a new minimally invasive procedure was developed that may cure some patients. The purpose of this clinical trial is to improve the curative technique to broaden the application of the new procedure.
Disturbances to the normal rhythm of the heart beat cause ~15% of deaths in our community. We wish to understand why the electrical signals in the heart can become chaotic. We will study a particular heart rhythm disturbance called acquired long QT syndrome to see if it is possible to develop a computer model that can accurately predict when and how arrhythmias will occur.
Re-engineering The Future Of Electrophysiological Measurements And Brain-Machine Interfaces Using A Novel Multi-Optrode Array
Funder
National Health and Medical Research Council
Funding Amount
$731,557.00
Summary
This proposal will develop scientific instrumentation to enable next generation interfacing with the heart and brain using light instead of electricity. Multichannel optical arrays will be fabricated using advanced materials and a control system developed and tested experimentally. The cost-effective technology will enable researchers to enhance our knowledge of the heart and brain with evolving optical approaches and offers future clinical applications for heart rhythm disorders and epilepsy.
Evaluating The Potential Of HERG Channel Agonists As Mechanistically Targeted Antiarrhythmics
Funder
National Health and Medical Research Council
Funding Amount
$414,786.00
Summary
Abnormal heart rhythms cause ~10 % of deaths in the western world and this number is increasing. To date there has been little success in identifying drugs that are effective in treating these disorders. By studying a rhythm disturbance called long QT syndrome we will examine whether specifically targeting drugs to the molecular building blocks of these arrhythmias is an appropriate route for development of more effective drugs.
Investigation Of Sudden Cardiac Death In The Young
Funder
National Health and Medical Research Council
Funding Amount
$682,823.00
Summary
Sudden cardiac death is a major tragedy in young people. In approximately one third of such cases, no cause of death is found at autopsy. This study will investigate the causes of sudden cardiac death in the young, with a specific emphasis on the underlying genetic causes of sudden unexplained death. This information will be used for screening surviving family relatives, thereby improving both diagnostic and treatment-prevention opportunities and reducing sudden cardiac death in our community.
How Regular Exercise Protects The Heart From Psychological Stresses
Funder
National Health and Medical Research Council
Funding Amount
$357,699.00
Summary
Regular exercise helps to protect the heart from the harmful effects of psychological stress. The present project seeks to discover the mechanisms that underpin this beneficial effect. The results will help to design new treatments that can augment the health benefits of exercise and provide an alternative for physically impaired individuals. The project may also allow to identify biochemical markers that can be used to optimise exercise program design for individuals and clinical populations.
Dynamic Action Potential Clamp Studies Of Drugs That Affect The Cardiac Action Potential
Funder
National Health and Medical Research Council
Funding Amount
$343,976.00
Summary
The development of drugs to treat and.or prevent cardiac arrhythmias have been plagued by the side-effect of actually increasing the risk of sudden death. One of the reasons for this is that drugs that work well in one part of the heart may cause problems in another part. We are developing a system called “dynamic action potential clamp” that will make it easier for researchers to assess the effect of drugs in different regions of both normal and diseased hearts.
The brain exerts a restraining influence over the heartbeat via the vagus nerves. This is known as cardiac vagal ‘tone’. It is strong when we are healthy but weak when we are sick. It has a positive influence on the health of the heart and perhaps the body generally. Vagal tone comes from the brain but, despite over 150 years’ research, nobody knows exactly where. Using a novel technique, we can track down its origins. This important basic knowledge may lead to ways to improve health.
The Role Of Mechanoelectric Feedback In Cardiac Arrhythmogenesis
Funder
National Health and Medical Research Council
Funding Amount
$307,550.00
Summary
Arrhythmias are disruptions of the normal electrical rhythm of the heart, and can vary from asymptomatic to fatal. It used to be thought that the electrical and mechanical functions of the heart muscle were essentially separate: the electrical activity triggered contraction something like pulling the trigger of a gun- once events were in motion, the electrical events played no further role. However, in recent years it has become apparent that this is an over-simplification of the real situation. ....Arrhythmias are disruptions of the normal electrical rhythm of the heart, and can vary from asymptomatic to fatal. It used to be thought that the electrical and mechanical functions of the heart muscle were essentially separate: the electrical activity triggered contraction something like pulling the trigger of a gun- once events were in motion, the electrical events played no further role. However, in recent years it has become apparent that this is an over-simplification of the real situation. In fact, the electrical activity of the heart is influenced strongly by the degree and timing of stretch to which the heart muscle is subjected, a process called Mechano-electric feedback. Since it can be demonstrated in isolated tissues, mechano-electric feedback must be an intrinsic property of the heart muscle. It has been shown in isolated heart preparations that passive stretch produces electrical disturbances in the normal action potential shape and propagation and that these electrical disturbances can be powerful enough to generate severe arrhythmias. There are paralells in human diseases. For example, atrial arrhythmias are common in older people, and it seems that these may be due to chronic stretch of the atria, as a consequence of high blood pressure. In addition, in those patients recovering from a heart attack, it seems likely that the damaged part of the heart muscle subjects the surrounding tissue to unusual mechanical stresses, and may trigger arrhythmias. This project aims to investigate the mechanisms underlying this mechano-electric feedback, in an attempt to understand some types of arrhythmias. Using molecular biology techniques, we will look at the gene expression of a novel type of stretch-activated potassium channel in both healthy and diseased animal hearts, with the aim of seeing if changes in the level of expression of these channels is correlated with changes in the response of the heart to stretch.Read moreRead less