Mitochondrial L-arginine Transport And Its Role In The Pathogenesis Of Heart Failure
Funder
National Health and Medical Research Council
Funding Amount
$525,660.00
Summary
Heart failure is a common disorder that is marked by significant symptoms and reduced survival. Reduced cardiac performance is the key responsible mechanism. At the tissue level, altered energy metabolism is a major contributor. Mitochondria are the cellular elements that produce energy and in this project we aim to study how a key process that regulates mitochondrial activity behaves in the setting of heart failure.
Development Of Quantitative Tools For Assessment Of Regional Cardiac Function By Echocardiography
Funder
National Health and Medical Research Council
Funding Amount
$209,430.00
Summary
The application of ultrasound imaging to the assessment of cardiac function (echocardiography) is an invaluable tool for the assessment of patients with known or suspected cardiac problems. The assessment of contraction in each region of the heart is probably the most important of the reasons for doing this test, as regional function is disturbed in patients with coronary artery disease, which is one of the most common causes of death in Australia. The problem is that this analysis is currently ....The application of ultrasound imaging to the assessment of cardiac function (echocardiography) is an invaluable tool for the assessment of patients with known or suspected cardiac problems. The assessment of contraction in each region of the heart is probably the most important of the reasons for doing this test, as regional function is disturbed in patients with coronary artery disease, which is one of the most common causes of death in Australia. The problem is that this analysis is currently completely subjective, and the reliability of the tool is based upon the availability of an experienced observer. This is particularly a problem in rural Australia, as most specialists with expertise in this modality work in the capital cities, and especially a problem in Queensland, where fewer than half of the population live in the capital. The cardiac imaging group at the University of Queensland have been working in collaboration with GE-Vingmed Ultrasound to develop a quantitative technique for the assessment of regional cardiac function since 1997. This collaboration has been the source of a number of published papers and presentations at international meetings. Our group is considered to be a world leader in the field and our industry partner is clearly the most focused of its competitors in addressing this problem. This submission seeks to address several remaining problems. The data thus far addressed function during stress, when the condition of most patients is similar. Tissue velocities are more variable at rest, and a more sophisticated approach is required to accurately measure the lower velocities in the resting state. This research plan seeks support for the development of a new, high frame-rate acquisition that would facilitate the examination of velocities relative to each other, so that translational motion of the heart does not influence the reading. This new method would then be validated against other techniques for assessing function and disease.Read moreRead less
Importance Of The Transmural Distribution Of Viable Myocardium To Outcome Of Patients After Revascularization
Funder
National Health and Medical Research Council
Funding Amount
$268,800.00
Summary
After a heart attack, up to 50% of tissue showing reduced function can recover if blood supply is returned to normal with bypass surgery or balloon angioplasty. Because these procedures may be risky in cardiac patients, the investigators have used various imaging approaches including radionuclide and ultrasound techniques to predict regions where function will recover after intervention. The results of these tests may be discordant because they assess separate attributes of cardiac muscle, and s ....After a heart attack, up to 50% of tissue showing reduced function can recover if blood supply is returned to normal with bypass surgery or balloon angioplasty. Because these procedures may be risky in cardiac patients, the investigators have used various imaging approaches including radionuclide and ultrasound techniques to predict regions where function will recover after intervention. The results of these tests may be discordant because they assess separate attributes of cardiac muscle, and selection of patients for intervention on the basis of recovery of regional function ignores some other aspects that may be important. These include avoidance of heart enlargement, improvement of exercise capacity, and avoidance of heart rhythm disturbances and even other heart attacks. In this study, the investigators seek to define the importance of the proportion and site of live (viable) myocardium to the parameters listed above. A new magnetic resonance technique will be used to identify whether radionuclide and ultrasound techniques assess different parts of the heart wall. The relative importance of these sites will be identified by comparing the outcome of patients who have live tissue in the inner half, compared with the outer half of the heart wall. This study will involve 180 patients who will undergo testing with magnetic resonance and radionuclide imaging. A subgroup will undergo dobutamine echocardiography. Their responses over follow-up will be assessed by accurate evaluation of heart size, exercise response, heart rhythm abnormalities and clinical events.Read moreRead less