Structural And Functional Determinants Of Spatiotemporal Periodicity In Cardiac Impulse Propagation
Funder
National Health and Medical Research Council
Funding Amount
$211,320.00
Summary
Abnormal heart rhythms (cardiac arrhythmias) are responsible for much morbidity and excess mortality in Australia. Although many abnormalities leading to an abnormal heart rhythm may be successfully treated by medications or minimally invasive operative procedures there are several important ones which are not. These include the most common significant cause of an abnormal heart rhythm, atrial fibrillation, and the arrhythmias responsible for approximately half of sudden deaths, ventricular tach ....Abnormal heart rhythms (cardiac arrhythmias) are responsible for much morbidity and excess mortality in Australia. Although many abnormalities leading to an abnormal heart rhythm may be successfully treated by medications or minimally invasive operative procedures there are several important ones which are not. These include the most common significant cause of an abnormal heart rhythm, atrial fibrillation, and the arrhythmias responsible for approximately half of sudden deaths, ventricular tachycardia and ventricular fibrillation. Atrial fibrillation is a leading cause of stroke. Sudden death is associated with aging and is an increasing problem because of the rising mean age of the population. Recent negative attention on the side effects of medications used for the treatment of cardiac arrhythmias has appropriately increased interest in curative approaches requiring no onging medications. These procedures usually rely on mapping electrical activity in the heart and interrupting abnormal electrical pathways using radiofrequency electrical current. The procedures are unsuccessful when existing techniques fail to identify the underlying mechanism responsible for the abnormal heart rhythm or when the source of the abnormal beating cannot be localised within the heart. In this project we investigate the fundamental basis for a new approach to these problems. By examining the variability of the beat rate and the variability of the beat rate at different points within the heart we may be able to identify arrhythmia mechanisms and localise arrhythmia sources. In this project we will examine in groups of cells the structures and types of electrical circuits which give rise to certain types of beat-to-beat variability in the heart. This information will be essential for the interpretation of information obtained in later human studies and the subsequent development of new curative procedures for these problems.Read moreRead less
Cardiac Resynchronisation Therapy And AV Node Ablation For Atrial Fibrillation In Heart Failure
Funder
National Health and Medical Research Council
Funding Amount
$3,274,979.00
Summary
Heart failure (HF) and Atrial Fibrillation (AF) are both significant health issues that often coexist. Cardiac resynchronisation therapy (CRT) is a proven therapy for HF with ventricular dyssynchrony (uncoordinated contraction of the left ventricle). While CRT reduces symptoms and improves survival in normal rhythm, there are mixed reports in patients with AF. This prospective randomised multicentre study, will assess the role of AV node ablation to improve outcomes in CRT in AF.
Guaranteeing Survival Into Adulthood, Physical Health And Psychological Well-being To Children Born With Single Ventricles.
Funder
National Health and Medical Research Council
Funding Amount
$342,773.00
Summary
Being born with a single pumping heart chamber is the most severe heart condition but thanks to several operations we can see them survive. A growing population of young functional adults now face an uncertain future and we have no options for them. A/Pr Y d’Udekem is a leading paediatric cardiac surgeon. His research aims to provide the medications, reinterventions and artificial hearts that are necessary to give them a longer and fulfilling life.
Very high levels of air pollution kill people. Although air quality is quite good in most Australian cities, the levels of particles are still too high. There are many sources of particles in the air including diesel vehicles and wood fires. There is a National Environment Protection Measure for particles less than 10 thousandths of a millimetre in diameter. However some recent overseas studies have suggested that tiny particles less than 0.1 thousandths of a millimetre might have the greatest e ....Very high levels of air pollution kill people. Although air quality is quite good in most Australian cities, the levels of particles are still too high. There are many sources of particles in the air including diesel vehicles and wood fires. There is a National Environment Protection Measure for particles less than 10 thousandths of a millimetre in diameter. However some recent overseas studies have suggested that tiny particles less than 0.1 thousandths of a millimetre might have the greatest effects on the heart and lungs. We will conduct the first Australian study of the health effects of these tiny particles. Particle counts will be measured in Melbourne by CSIRO using state of the art equipment. Two groups of older subjects will be recruited: patients with chronic lung diseases such as emphysema and patients with heart disease. They will perform regular breathing tests and-or have the electrical activity of their hearts recorded. The recordings will be analysed to detect small variations in heart rate. If we find relationships between particle counts and lung function or heart rate variability, this will provide new evidence of the health effects of air pollution. When the NEPMs are revised, new measures may be required for tiny particles. Particle counts can then be reduced by measures such as better controlling diesel exhaust and more efficient wood stoves.Read moreRead less
The Role Of Calcium And TRPC Channels In Sinoatrial Node Ageing
Funder
National Health and Medical Research Council
Funding Amount
$385,301.00
Summary
The failure of pacemaker function is a common clinical problem in the elderly who become more susceptible to cardiac arrhythmias. We recently discovered a new calcium channel called the transient receptor potential canonical channel (TRPC) in the pacemaker cells. The aim of this research is to study the role of TRPC channels in pacemaker ageing. Improved understanding of the mechanisms of the pacemaker ageing may provide new therapeutic strategies for reducing the risk of cardiac arrhythmias.
Reduced Baroreceptor Reflex Control Of Heart Rate In Chronic Renal Failure
Funder
National Health and Medical Research Council
Funding Amount
$490,288.00
Summary
People with kidney disease are more likely to die of heart disease than their ailing kidneys. One reason is because their hearts do not respond properly to changes in blood pressure, as the nerve circuits controlling the heart become dysfunctional. We will examine where and why components of this circuit are unable to respond to changes in blood pressure. This will help guide new treatments to reduce the incidence of heart disease and risk of death associated with kidney disease.