title: Surgical ventricular restoration in patients with ischemic dilated cardiomyopathy: evaluation of systolic and diastolic ventricular function, wall stress, dyssynchrony, and mechanical efficiency by pressure-volume loops.
abstract: OBJECTIVE
  Surgical ventricular restoration aims at improving cardiac function by normalization of left ventricular shape and size. Recent studies indicate that surgical ventricular restoration is highly effective with an excellent 5-year outcome in patients with ischemic dilated cardiomyopathy. We used pressure-volume analysis to investigate acute changes in systolic and diastolic left ventricular function, mechanical dyssynchrony and efficiency, and wall stress.
  
  
  METHODS
  In 3 patient groups (total, n = 33), pressure-volume loops were measured by conductance catheter before and after surgery. The main study group consisted of 10 patients with ischemic dilated cardiomyopathy (New York Heart Association class III/IV, left ventricular ejection fraction <30%) who had surgical ventricular restoration and coronary artery bypass grafting. In this group, 7 patients had additional restrictive mitral annuloplasty. To assess potential confounding effects of restrictive mitral annuloplasty and cardiopulmonary bypass, we included a group of 10 patients (New York Heart Association class III/IV, left ventricular ejection fraction <30%) who had isolated restrictive mitral annuloplasty and a group of 13 patients with preserved left ventricular function who had isolated coronary artery bypass grafting.
  
  
  RESULTS
  After surgical ventricular restoration, end-diastolic and end-systolic volumes were reduced from 211 +/- 54 to 169 +/- 34 mL (P = .03) and from 147 +/- 41 to 110 +/- 59 mL (P = .04), respectively. Left ventricular ejection fraction (from 27% +/- 7% to 37% +/- 13%, P = .04) and end-systolic elastance (from 1.12 +/- 0.71 to 1.57 +/- 0.63 mm Hg/mL, P = .03) improved. Peak wall stress (from 358 +/- 108 to 244 +/- 79 mm Hg, P < .01) and mechanical dyssynchrony (from 26% +/- 4% to 19% +/- 6%, P < .01) were reduced, whereas mechanical efficiency improved (from 0.34 +/- 13 to 0.49 +/- 0.14, P = .03). End-diastolic pressure increased (from 13 +/- 6 to 20 +/- 5 mm Hg, P < .01), whereas the diastolic chamber stiffness constant tended to be increased (from 0.021 +/- 0.009 to 0.037 +/- 0.021 mL(-1), NS).
  
  
  CONCLUSIONS
  Surgical ventricular restoration achieves normalization of left ventricular volumes and improves systolic function and mechanical efficiency by reducing left ventricular wall stress and mechanical dyssynchrony.
authors.affiliation: Department of Cardiology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Sven A F
authors.initials: SA
authors.lastname: Tulner
authors.forename: Paul
authors.initials: P
authors.lastname: Steendijk
authors.forename: Robert J M
authors.initials: RJ
authors.lastname: Klautz
authors.forename: Jeroen J
authors.initials: JJ
authors.lastname: Bax
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Schalij
authors.forename: Ernst E
authors.initials: EE
authors.lastname: van der Wall
authors.forename: Robert A E
authors.initials: RA
authors.lastname: Dion
mesh_terms: D001696:Biomechanical Phenomena; D006348:Cardiac Surgical Procedures / Q000379:methods; D002311:Cardiomyopathy, Dilated / Q000209:etiology / Q000503:physiopathology* / Q000601:surgery*; D003971:Diastole; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000150:complications; D011312:Pressure; D013599:Systole; D016276:Ventricular Function