Avtor/Urednik		Poglajen, Gregor; Harlander, Matevž; Geršak, Borut
Naslov		Regurgitant flow in ischemic and dilative mitral regurgitation
Tip		članek
Vir		J Heart Valve Dis
Vol. in št.		Letnik 18, št. 6
Leto izdaje		2009
Obseg		str. 598-606
Jezik		eng
Abstrakt		Background and aim of the study: It is well established that there are geometric differences between ischemic and dilative mitral regurgitation (MR), yet data on the hemodynamic consequences of these differences are scarce. The study aim was to determine whether mitral regurgitant flows in ischemic MR dif- fer from those in dilative MR. Methods: A left heart simulator was developed to evaluate possible differences in regurgitant flows between two pathological mitral valve configurations, ischemic and dilative. Ischemic MR was simulated by increasing the baseline intercommissural diameter (CC) by 10%, the baseline septolateral (SL) diameter by 30%, and by displacing the posteromedial papillary muscle (PM) to the apical posterolateral position. Dilative MR was simulated by increasing the baselineSL and CC diameters by 30%, and by a symmetrical displacement of both PMs. Mitral regurgitant flow measurements were carried out under transmitral pressures ranging from 40 to 140 mmHg (increments of 15 mmHg). Camera snapshots of the mitral annulus were used to accurately determine mitral annular Results: A total of 24 measurements was made on four porcine mitral valves; 14 to evaluate ischemic MR, and 10 to evaluate dilative MR. In ischemic MR, a constant regurgitant flow was observed throughout the pressure range tested. In dilative MR, increasing the transmitral pressure caused the regurgitant flows to decrease exponentially. The mitral annulus snapshot analysis showed that displacement of the posteromedial PM in ischemic MR caused the regurgitation orifice to appear at the tented side of the valve. An additional regurgitation orifice was formed through bulging (prolapse) of the leaflets at the contralateral commissure. (Abstract truncated at 2000 characters)
Deskriptorji		MITRAL VALVE INSUFFICIENCY CARDIOMYOPATHY, CONGESTIVE MYOCARDIAL ISCHEMIA MODELS, CARDIOVASCULAR BLOOD PRESSURE BLOOD FLOW VELOCITY SWINE