Heart failure (HF) affects 15 million Europeans and entails higher mortality and health care costs than cancer. EPLORE addresses this issue by prospective epidemiological research in 4 European countries and by a proof-of-concept clinical trial. WP1 will for the first time at the population level document the incidence and progression of subclinical LV dysfunction and clarify whether asymptomatic LV dysfunction, as picked up by the newest echocardiographic techniques, predicts cardiovascular (CV) outcomes, including HF. WP2 will investigate the contribution of ventricular-arterial coupling disease and mechanical LV dyssynchrony to subclinical LV dysfunction. WP3 will identify a set of urinary polypeptides that signify early LV dysfunction and validate these biomarkers by showing that they predict deterioration of LV function, progression to HF and the incidence of CV complications over and beyond established risk factors. WP3 will also search for novel panels of circulating biomarkers, of which combined measurement will add information (accuracy, sensitivity and specificity) to established biomarkers (e.g., NT-proBNP) and identify genetic variants involved in the progression of LV dysfunction, either causally or as biomarker. WP4 consists of a randomised clinical trial to translate in a high-risk high-gain setting the results of WPs 1-3 into clinical practice and to identify a new treatment modality that potentially slows progression of diastolic LV dysfunction. Dissemination in WP5 will contribute to new guidelines for the prevention and treatment of HF. WP6 includes governance, monitoring research strategies and output, and protection of IPR. In conclusion, EPLORE will advance risk stratification and the early diagnosis of subclinical HF. The project will potentially result into specific treatments for diastolic LV dysfunction and inform guidelines for prevention and treatment of HF. It will benefit 20% of Europeans who currently have subclinical LV dysfunction.