In Austria, over 200,000 patients suffer from symptomatic heart failure, and about 10,000 are newly diagnosed each year. The majority will not survive 5 years following diagnosis despite best possible therapy. Often, quality of life is reduced by severe impairment in daily activities and frequent hospitalizations (29,360 hospital stays in Austria in the year 2000). Medical costs in excess of €10,000 per hospitalization contribute to the high socio-economic burden of the disease.
Heart Failure is the only major cardiovascular disorder with a steady increase in prevalence and is therefore expected to increasingly strain public health systems. Heart failure has been commonly attributed to a reduced ejection fraction (EF), usually termed “systolic” heart failure. However, in a considerable number of patients (up to 50%) with heart failure symptoms of cardiac origin, systolic function is preserved. While the pathophysiology in these patients is poorly understood, patients are typically characterized by impaired relaxation and filling of the heart during diastole. The disease entity is now termed “diastolic” heart failure, and its prognosis is as poor as in systolic heart failure.
Chronic heart failure – irrespective of EF – is associated with structural remodeling of the heart which precedes heart failure symptoms and contributes to deterioration. Current diagnosis and therapy are based on overt symptoms of heart failure and evidence of structural and/or functional heart disease. As a consequence, patients are often identified only at a late stage of cardiac remodeling and heart failure. While risk factors for heart failure have been established (e.g. hypertension, atherosclerosis or metabolic disorders), the mechanisms of early cardiac remodeling and heart failure development are largely unknown. The management of patients at risk for heart failure is complicated by the lack of early markers for cardiac remodeling that would indicate the necessity to initiate a more specific therapy.
Furthermore, current therapeutic concepts are symptom-oriented and established for advanced heart failure stages. In addition, most available heart failure therapies are not effective in diastolic heart failure patients, emphasizing the need for a better understanding of the underlying pathophysiological differences in the manifestation and progression of systolic and diastolic heart failure. Chronic heart failure is characterized by unpredictable episodes of cardiac decompensation and arrhythmias, often necessitating urgent hospitalization and often associated with prolonged recovery. Decompensation might be preventable by timely adaptation of therapy.
However, early indicators for the detection of cardiac deterioration in individual patients have not yet been established.