Successful ‘quadrangular' pacing in a non-responder patient to cardiac resynchronization therapy

A 77-year-old man with a previous history of coronary heart disease, depressed left ventricular ejection fraction (LVEF) of 30%, and permanent atrial fibrillation was referred for decompensated heart failure. A radiofrequency ablation of the atrioventricular junction had been performed because of an uncontrolled high ventricular rate, with implantation of a single-chamber pacemaker with a bipolar lead screwed in the right ventricular apex (ARV, Panel A ). Despite optimal medical therapy, he had then been hospitalized several times for congestive heart failure. A biventricular pacemaker …