Efficacy And Mechanisms Of Exercise Training In Diastolic Heart Failure
Funder
National Health and Medical Research Council
Funding Amount
$385,250.00
Summary
Heart failure is modern epidemic which presents a significant public health burden, due to a high mortality, frequent hospital admissions and impaired functional capacity. Although the typical heart failure patient presents with a reduced contractile function, many patients have typical heart failure symptoms but with normal contraction. The problem in these patients seems to relate to the heart's ability to fill with blood, and this entity is known as diastolic heart failure (DHF). This syndrom ....Heart failure is modern epidemic which presents a significant public health burden, due to a high mortality, frequent hospital admissions and impaired functional capacity. Although the typical heart failure patient presents with a reduced contractile function, many patients have typical heart failure symptoms but with normal contraction. The problem in these patients seems to relate to the heart's ability to fill with blood, and this entity is known as diastolic heart failure (DHF). This syndrome is most frequently due to ischemic or hypertensive heart disease, and most commonly occurs in the elderly. The optimal management of DHF is not well defined, although some drug trials are currently in progress. A number of studies have shown exercise training to improve functional capacity by 15-20% in typical heart failure. However, training has not so far been trialled in DHF. In this multicenter, multi-disciplinary study, we will study a training and control group to determine whether exercise capacity and DHF symptoms are responsive to exercise training. This work will teach us about the optimum exercise prescription, in terms of the duration and nature of training, as well as the safety and effectiveness of exercise training. By using a number of sensitive measurements of heart and vessel function (in which our group has special expertise), we will identify whether exercise training exerts its effect through improvement in vascular function and myocardial properties. If successful, the clinical implications of this study are that; 1. Exercise training will be adopted to improve functional capacity and symptoms of DHF 2. The merits of aerobic and strength training will be identified in DHF 3. Abnormal blood vessel function will be identified as a major and reversible contributor to DHFRead moreRead less
A pressure pulse may be felt at the wrist with every heart beat. New technology allows the analysis of this pulse and provides information that may help doctors make decisions about a patients risk related to blood pressure as well as the effect of drug treatment. The research aims to determine the clinical significance of pressure pulse analysis at rest and during light exercise. It is expected that the new technology will improve the way people with high blood pressure are treated.
A Supervised Exercise Programme Following Hospitalisation For Heart Failure: Does It Add To Disease Management?
Funder
National Health and Medical Research Council
Funding Amount
$730,966.00
Summary
Congestive heart failure (CHF) is a common, disabling condition. Outcomes are improved by a post-hospital disease management programme (DMP) including education, support and followup from a team of nurses, doctors and other health professionals. This study looks at whether adding a supervised exercise programme to a DMP can reduce death rates and hospital stays, and improve physical function and depression in patients with a recent hospital stay for CHF.
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
Vascular Effects Of Exercise Training And Lipid-lowering Therapy At Rest And During Exercise In Hypercholesterolaemia
Funder
National Health and Medical Research Council
Funding Amount
$241,650.00
Summary
The health of the cells which line blood vessels, endothelial cells, is now known to be important in maintaining normal function of the circulation. In patients with elevated blood cholesterol concentration, the function of these cells is abnormal and this is considered to contribute importantly to the blood vessel dysfunction and cardiovascular disease seen in this condition. We have recently demonstrated that drug therapy aimed at decreasing cholesterol concentration in the blood can significa ....The health of the cells which line blood vessels, endothelial cells, is now known to be important in maintaining normal function of the circulation. In patients with elevated blood cholesterol concentration, the function of these cells is abnormal and this is considered to contribute importantly to the blood vessel dysfunction and cardiovascular disease seen in this condition. We have recently demonstrated that drug therapy aimed at decreasing cholesterol concentration in the blood can significantly improve blood vessel function. In other studies we have demonstrated that exercise training improves blood vessel function. The purpose of this research is to determine whether high blood cholesterol impairs exercise capacity by limiting blood flow to exercising muscle. It is also our goal to determine whether exercise training can produce benefit additional to that resulting from lowering cholesterol in those with initially high cholesterol. Blood vessel function will be studied at rest, in response to pharmacological stimulation and during exercise. Vascular function in the forearm will be assessed using synchronised ultrasound (high frequency sound, sonar) and Doppler measures which assess the size of, and flow in, the large artery near the elbow crease. During measurements, procedures are undertaken to alter flow in the arm blood vessels, some depending upon functional ability of the endothelial cells and some independent of those cells. In addition to assessment of blood vessel function, measurements of exercise tolerance will be taken before and after each intervention. By examining the effects of lipid-lowering and exercise training on rest and exercise blood flow responses, this research will help determine the best approach to improving blood vessel function and cardiovascular fitness in patients with high cholesterol.Read moreRead less
Body Composition Changes In Cardiac Cachexia: Pathophysiology, Quantification And Approaches To Therapy
Funder
National Health and Medical Research Council
Funding Amount
$120,000.00
Summary
Cachexia is weight loss and weakness caused by disease, or as a side effect of illness. Congestive heart failure is a common cardiovascular condition that is accompanied by high mortality (up to 50% over 2 years) and considerable suffering. People with congestive heart failure often develop cachexia. This project will explore the mechanisms responsible for the development of cachexia using an animal model of cardiac cachexia that the researchers have developed. It will be complemented by an exam ....Cachexia is weight loss and weakness caused by disease, or as a side effect of illness. Congestive heart failure is a common cardiovascular condition that is accompanied by high mortality (up to 50% over 2 years) and considerable suffering. People with congestive heart failure often develop cachexia. This project will explore the mechanisms responsible for the development of cachexia using an animal model of cardiac cachexia that the researchers have developed. It will be complemented by an examination of the effects of exercise on measures of cachexia in patients with congestive heart failure. The researchers believe that this study will supply valuable new information about the development of cachexia and lead to new therapies for this syndrome.Read moreRead less