title: Afterload reduction in severe aortic regurgitation.
abstract: This study was designed to assess the effects of afterload reduction in asymptomatic patients with severe aortic regurgitation (AR) and maintained LV function by cine-MRI. We studied 13 patients at baseline and after 0.2 mg/kg Hydralazine (I.V.). Patients were stratified according to the volumetric LV response to acute afterload reduction: Group I comprised patients with improved LV response; Group II comprised patients with unchanged or deteriorated LV response. Baseline LV function and severity of AR were not significantly different between groups. However, regurgitant fraction decreased (50 +/- 12 vs. 36 +/- 9%; P < 0.03) and cardiac output increased (4.9 +/- 1.4 vs. 7.1 +/- 1.6l/minute; P < 0,001) in Group I and remained unchanged in Group II (54 +/- 10 vs. 55 +/- 10%, P = n.s. and 5.5 +/- 1.4 vs. 6.6 +/- 0.9l/minute; P = n.s.) during maximal vasodilation. Beat-to-beat analysis revealed a decrease of left ventricular endsystolic volume index in group I (48 +/- 13 vs. 37 +/- 9 ml/beat; P < 0.05) and no change in group II (61 +/- 20 vs. 62 +/- 20 ml/beat; P = n.s.). In the natural history of chronic AR, the absence of improved LV performance during acute vasodilation using beat-to-beat analysis by MRI may identify patients with more advanced cardiac adaptation to chronic volume overload.
authors.affiliation: Department of Radiology, University Hospital Vienna, Vienna, Austria. Hoffmann@helix.mgh.harvard.edu
authors.forename: U
authors.initials: U
authors.lastname: Hoffmann
authors.forename: H
authors.initials: H
authors.lastname: Frank
authors.forename: T
authors.initials: T
authors.lastname: Stefenelli
authors.forename: B
authors.initials: B
authors.lastname: Kaiser
authors.forename: U
authors.initials: U
authors.lastname: Klaar
authors.forename: S
authors.initials: S
authors.lastname: Globits
mesh_terms: D000328:Adult; D001022:Aortic Valve Insufficiency / Q000188:drug therapy* / Q000503:physiopathology*; D005240:Feasibility Studies; D005260:Female; D006439:Hemodynamics; D006801:Humans; D006830:Hydralazine / Q000494:pharmacology*; D019028:Magnetic Resonance Imaging, Cine; D008297:Male; D014665:Vasodilator Agents / Q000494:pharmacology*; D016277:Ventricular Function, Left / Q000187:drug effects* / Q000502:physiology
chemical_list: D014665:Vasodilator Agents; D006830:Hydralazine