The BLOCK-HF trial provides good evidence to support the theoretical benefit of CRT in patients with even mild LV dysfunction who require a high burden of ventricular pacing as a consequence of ...

had non-ischaemic LV systolic dysfunction, with a mean EF of 34.4 ± 10.8% (range 10–48%). Sixteen per cent of patients underwent mitral valve surgery; 166 patients (41.2%) had mild MR ...

and low ejection fraction associated with mild left ventricular dilation, among other signs of heart dysfunction. Transmission electron micrographs of myocardial biopsies from two of these ...