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.
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.
Microwave And Laser Energies For Percutaneous Cardiac Ablation For The Cure Of Arhythmias
Funder
National Health and Medical Research Council
Funding Amount
$331,527.00
Summary
The commonest beating disorder of the heart is atrial fibrillation (AF). Whilst it can occur at any age it is more common in the elderly with 12% Australians over 70 y.o having it. AF is the cause of a third of all strokes and increases the risk of dying from any heart disease. Ventricular tachycardia (VT) is the commonest cause of death in the year after a heart attack. Currently these beating disorders are in most cases incurable and respond poorly to medications. We have developed an operatio ....The commonest beating disorder of the heart is atrial fibrillation (AF). Whilst it can occur at any age it is more common in the elderly with 12% Australians over 70 y.o having it. AF is the cause of a third of all strokes and increases the risk of dying from any heart disease. Ventricular tachycardia (VT) is the commonest cause of death in the year after a heart attack. Currently these beating disorders are in most cases incurable and respond poorly to medications. We have developed an operation for AF which is done by open heart surgery. It has been successful at curing some patients who suffer from AF and uses radiofrequency energy. The difficulty of radiofrequency energy is that it is not suitable in a large number of cases for this operation. We are developing Laser and Microwave catheters as alternatives to RF so that the success of the operation can be improved. These new microwave and laser catheters are being designed and tested to be used primarily in a minimally invasive procedure. They would be inserted via the veins with the patient under sedation. This would allow patients to go home sooner and have a recovery period of only a few days. As well as their application in the top chamber of the heart (atrium) for AF, these new energies will be adapted for minimally invasive operations in the ventricle (lower chamber) of the heart for the treatment of ventricular tachycardia. By developing a technique such as this, cure of AFand VT will be available to many more people, helping reduce the strokes, heart failure and premature deaths from these two heart conditions.Read moreRead less
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