Two-dimensional echocardiographic imaging, targeted M-mode and Doppler ultrasound measurements will be obtained in each patient. M-mode measurements are taken according to the guidelines laid down by the American Society of Echocardiography. All echocardiographic data will represent the mean of 3 measurements on different cardiac cycles. It is the aim of the STOP HF investigators that a single observer will conduct all measurements, recording archive images in a blinded fashion.