title: Letter by Guarracino et al regarding article, "Direct myocardial effects of levosimendan in humans with left ventricular dysfunction: alteration of force-frequency and relaxation-frequency relationships".
authors.forename: Fabio
authors.initials: F
authors.lastname: Guarracino
authors.forename: Luigi
authors.initials: L
authors.lastname: Tritapepe
authors.forename: Andrea
authors.initials: A
authors.lastname: Morelli
mesh_terms: D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D006801:Humans; D006835:Hydrazones / Q000494:pharmacology* / Q000627:therapeutic use*; D009200:Myocardial Contraction / Q000187:drug effects* / Q000502:physiology; D011724:Pyridazines / Q000494:pharmacology* / Q000627:therapeutic use*; D000077464:Simendan; D018487:Ventricular Dysfunction, Left / Q000188:drug therapy* / Q000503:physiopathology
chemical_list: D006835:Hydrazones; D011724:Pyridazines; D000077464:Simendan