title: Surgical ventricular restoration improves mechanical intraventricular dyssynchrony in ischemic cardiomyopathy.
abstract: BACKGROUND
  In ischemic cardiomyopathy, dyssynchrony of left ventricular (LV) mechanical contraction produces adverse hemodynamic consequences. This study tests the capacity of geometric rebuilding by surgical ventricular restoration (SVR) to restore a more synchronous contractile pattern after a mechanical, rather than electrical, intervention.
  
  
  RESULTS
  A prospective study of the global and regional components of dyssynchrony was conducted in 30 patients (58+/-8 years of age) undergoing SVR at the Cardiothoracic Center of Monaco. The protocol used simultaneous measurements of ventricular volumes and pressure to construct pressure/volume (P/V) and pressure/length (P/L) loops. Angiograms were done before and after SVR to study a 600-ms cycle during atrial pacing at 100 bpm. Mean QRS duration was similar, at 100+/-17 ms preoperatively and 114+/-28 ms postoperatively (NS). Preoperative LV contraction was highly asynchronous, because P/V loops showed abnormal isometric phases with a right shifting. Endocardial time motion was either early or delayed at the end-systolic phase so that P/L loops were markedly abnormal in size, shape, and orientation. Postoperatively, SVR resulted in leftward shifting of P/V loops and increased area; endocardial time motion and P/L loops almost normalized to allow a better contribution of single regions to global ejection. The hemodynamic consequences of SVR were improved ejection fraction (30+/-13% to 45+/-12%; P=0.001); reduced end-diastolic and end-systolic volume index (202+/-76 to 122+/-48 and 144+/-69 to 69+/-40 mL/m(2); P=0.001); more rapid peak filling rate (1.75+/-0.7 to 2.32+/-0.7 EDV/s; P=0.0001); peak ejection rate (1.7+/-0.7 to 2.6+/-0.9 Sv/s; P=0.0002), and mechanical efficiency (0.56+/-0.15 to 0.65+/-0.18; P=0.04).
  
  
  CONCLUSIONS
  SVR produces a mechanical intraventricular resynchronization that improves LV performance.
authors.affiliation: Department of Critical Care Medicine, University of Florence, Italy. marad@tin.it
authors.forename: Marisa
authors.initials: M
authors.lastname: Di Donato
authors.forename: Anna
authors.initials: A
authors.lastname: Toso
authors.forename: Vincent
authors.initials: V
authors.lastname: Dor
authors.forename: Michel
authors.initials: M
authors.lastname: Sabatier
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Barletta
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Menicanti
authors.forename: Fabio
authors.initials: F
authors.lastname: Fantini
mesh_terms: D000368:Aged; D006328:Cardiac Catheterization; D003971:Diastole; D004699:Endocardium / Q000503:physiopathology; D005260:Female; D006352:Heart Ventricles / Q000601:surgery*; D006801:Humans; D007387:Internal Mammary-Coronary Artery Anastomosis; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery; D009200:Myocardial Contraction; D017202:Myocardial Ischemia / Q000150:complications / Q000601:surgery*; D011446:Prospective Studies; D013318:Stroke Volume; D013599:Systole; D014463:Ultrasonography; D018487:Ventricular Dysfunction, Left / Q000209:etiology / Q000601:surgery*; D016277:Ventricular Function, Left