Heart Rhythm Heart Rhythm Transient and rapid QRS-widening associated with a J-wave pattern predicts impending ventricular fibrillation in experimental myocardial infarction Demidova M. M. Martín-Yebra A. Van Der Pals Koul S. Erlinge D. Laguna P. Universidad de Zaragoza Martínez J. P. Universidad de Zaragoza Platonov P. G. 2014 research-article