All participants will undergo a standardized diagnostic work-up to establish or rule out heart failure. In those participants with an abnormal ECG and/or elevated natriuretic peptide level additional echocardiography will be performed at the outpatient clinic of the Diakonessenhuis in Zeist. The definite diagnosis of heart failure ('systolic' or 'diastolic') will be established by an expert panel consisting of two cardiologists and a general practitioner. The panel will apply the criteria of the updated heart failure guidelines (2008) of the European Society of Cardiology (ESC). Patients with heart failure will subsequently be treated by their own general practitioner. The participating general practitioners will be randomly divided into either care as usual (control group) or special uptitration (intervention group). Both groups will be using medication as recommended in the Dutch heart failure standard. However, general practitioners in the intervention group will be especially trained in the practical appliance of this guideline: the initiation of diuretics and ACE-inhibitors and structured uptitration of ACE-inhibitors and beta-blockers. In the training, practical examples will be used concerning barriers the general practitioners themselves encountered when using this medication. In the intervention group, patients with 'systolic' heart failure will receive the recommended maximal dose or the highest tolerated dose. Patients with 'diastolic' heart failure will receive optimal blood pressure and heart rate control with the preferred cardiovascular drugs. At baseline and six months after heart failure is established or ruled out, participants are asked to perform the six-minute walk test and fill out quality of life questionnaires. During those six months, only participants with heart failure will additionally fill out one of these questionnaires every three weeks. Also after six months, electronical files of the general practitioners will be scrutinized to assess the (dosage of) prescribed medication and visits to general practice and cardiology department.