title: Vortices formed on the mitral valve tips aid normal left ventricular filling.
abstract: For the left ventricle (LV) to function as an effective pump it must be able to fill from a low left atrial pressure. However, this ability is lost in patients with heart failure. We investigated LV filling by measuring the cardiac blood flow using 2D phase contrast magnetic resonance imaging and quantified the intraventricular pressure gradients and the strength and location of vortices. In normal subjects, blood flows towards the apex prior to the mitral valve opening, and the mitral annulus moves rapidly away after the valve opens, with both effects enhancing the vortex ring at the mitral valve tips. Instead of being a passive by-product of the process as was previously believed, this ring facilitates filling by reducing convective losses and enhancing the function of the LV as a suction pump. The virtual channel thus created by the vortices may help insure efficient mass transfer for the left atrium to the LV apex. Impairment of this mechanism contributes to diastolic dysfunction, with LV filling becoming dependent on left atrial pressure, which can lead to eventual heart failure. Better understanding of the mechanics of this progression may lead to more accurate diagnosis and treatment of this disease.
authors: Department of Mechanical Engineering, Virginia Tech, 100 Randolph Hall, Blacksburg, VA 24060, USA.
authors: John J
authors: JJ
authors: Charonko
authors: Rahul
authors: R
authors: Kumar
authors: Kelley
authors: K
authors: Stewart
authors: William C
authors: WC
authors: Little
authors: Pavlos P
authors: PP
authors: Vlachos
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D054144:Heart Failure, Diastolic / Q000000981:diagnostic imaging / Q000503:physiopathology*; D006352:Heart Ventricles / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000000981:diagnostic imaging / Q000503:physiopathology*; D008955:Models, Cardiovascular; D011859:Radiography; D016277:Ventricular Function, Left
references: J Am Coll Cardiol. 1998 Oct;32(4):865-75
references: 9768704
references: J Magn Reson Imaging. 2000 Aug;12(2):321-9
references: 10931596
references: Cardiovasc Ultrasound. 2003 Apr 01;1:3
references: 12718756
references: Magn Reson Med. 2001 May;45(5):872-9
references: 11323814
references: J Am Soc Echocardiogr. 2002 Mar;15(3):219-24
references: 11875384
references: Circulation. 1994 May;89(5):2241-50
references: 8181149
references: Am J Physiol Heart Circ Physiol. 2001 Jun;280(6):H2507-15
references: 11356605
references: Circ Res. 1992 Jan;70(1):9-19
references: 1345778
references: J Am Soc Echocardiogr. 2002 Jul;15(7):715-22
references: 12094170
references: Magn Reson Med. 2003 Jun;49(6):1056-66
references: 12768584
references: J Biomech Eng. 2000 Dec;122(6):667-74
references: 11192390
references: Cardiovasc Res. 1994 Dec;28(12):1821-7
references: 7867035
references: Eur J Cardiothorac Surg. 2006 Apr;29 Suppl 1:S98-106
references: 16567105
references: Am J Physiol Heart Circ Physiol. 2012 Nov 15;303(10):H1255-62
references: 22961866
references: Circulation. 2009 Sep 1;120(9):802-9
references: 19720946
references: Eur Heart J. 1994 Mar;15(3):318-27
references: 8013503
references: Proc Natl Acad Sci U S A. 2006 Apr 18;103(16):6305-8
references: 16606852
references: J Am Coll Cardiol. 1997 Jul;30(1):8-18
references: 9207615
references: Ann Biomed Eng. 2007 Dec;35(12):2050-64
references: 17899379
references: Ann Biomed Eng. 2012 Dec;40(12):2652-62
references: 22805980
references: J Appl Physiol (1985). 2008 Feb;104(2):513-20
references: 18032579
references: JACC Cardiovasc Imaging. 2011 Jan;4(1):37-46
references: 21232702
references: ASAIO J. 2007 Jan-Feb;53(1):8-16
references: 17237643
references: Nature. 2000 Apr 13;404(6779):759-61
references: 10783888
references: Ultrasound Med Biol. 2007 Jun;33(6):823-41
references: 17434662
references: JAMA. 2003 Jan 8;289(2):194-202
references: 12517230
references: J Am Coll Cardiol. 1992 Aug;20(2):420-32
references: 1634681
references: J Am Coll Cardiol. 1993 Jun;21(7):1697-700
references: 8496539
references: Circulation. 2005 Nov 8;112(19):2888-90
references: 16275877
references: J Am Coll Cardiol. 2003 May 7;41(9):1590-7
references: 12742302
references: J Am Coll Cardiol. 2007 Feb 27;49(8):917-20
references: 17320751
references: J Am Soc Echocardiogr. 2009 Feb;22(2):107-33
references: 19187853
references: Circulation. 1989 Jun;79(6):1393-7
references: 2498007
references: Magn Reson Med. 2005 Apr;53(4):877-84
references: 15799069
references: J Biomech. 1996 Apr;29(4):503-11
references: 8964780
references: J Am Soc Echocardiogr. 2006 Jul;19(7):872-9
references: 16824996
references: JACC Cardiovasc Imaging. 2008 Nov;1(6):705-17
references: 19356506
references: J Comput Assist Tomogr. 2011 Jan-Feb;35(1):108-12
references: 21245695
references: Am J Cardiol. 2005 Mar 1;95(5):603-6
references: 15721099
references: Circulation. 1988 Sep;78(3):661-71
references: 3409502
references: J Am Coll Cardiol. 2007 Feb 27;49(8):899-908
references: 17320749
references: Hellenic J Cardiol. 2012 Nov-Dec;53(6):458-69
references: 23178429
references: J Am Coll Cardiol. 2006 Jan 3;47(1):163-72
references: 16386681