title: Left ventricular pacing vector selection by novel echo-particle imaging velocimetry analysis for optimization of quadripolar cardiac resynchronization device: a case report.
abstract: BACKGROUND
  The availability of pacing configurations offered by quadripolar left ventricular leads could improve patients' response to cardiac resynchronization therapy; however, the selection of an optimal setting remains a challenge. Echo-particle imaging velocimetry has shown that regional anomalies of synchrony/synergy of the left ventricle are related to the alteration, reduction, or suppression of the physiological intracavitary pressure gradients. These observations are also supported by several numerical models of the left ventricle that have shown the close relationship between wall motion abnormalities, change of intraventricular flow dynamics, and abnormal distribution of forces operating on the ventricular endocardium.
  
  
  METHODS
  A 73-year-old white man in New York Heart Association III functional class with an ejection fraction of 27.5 % did not improve after 1 month of cardiac resynchronization therapy. Five configurations were tested and settings were defined by optimizing intraventricular flow. After 6 months, he became New York Heart Association II class with left ventricular ejection fraction of 53.2 %.
  
  
  CONCLUSIONS
  The abnormal dynamic of pressure gradients during the cardiac cycle, through biohumoral endocrine, autocrine, and paracrine transduction, may lead to structural changes of the myocardial walls with subsequent left ventricular remodeling. The echo-particle imaging velocimetry technique may be useful for elucidating the favorable effects of cardiac resynchronization therapy on intraventricular fluid dynamics and it could be used to identify appropriate pacing setting during acute echocardiographic optimization of left pacing vector.
authors.affiliation: Department of Cardiology, Monaldi Hospital, AORN Ospedali dei Colli, Via Leonardo Bianchi, 80131, Naples, Italy. alfromar@alice.it.
authors.forename: Alfonso/A Roberto/R
authors.initials: AR
authors.lastname: Martiniello
authors.affiliation: Department of Engineering and Architecture, University of Trieste, Trieste, Italy.
authors.forename: Gianni/G
authors.initials: G
authors.lastname: Pedrizzetti
authors.affiliation: Department of Cardiology, Monaldi Hospital, AORN Ospedali dei Colli, Via Leonardo Bianchi, 80131, Naples, Italy.
authors.forename: Valter/V
authors.initials: V
authors.lastname: Bianchi
authors.affiliation: Institute of Cardiology and Center of Excellence on Aging, 'G. d'Annunzio' University , Chieti, Italyᅟ
authors.forename: Giovanni/G
authors.initials: G
authors.lastname: Tonti
authors.affiliation: Department of Cardiology, Monaldi Hospital, AORN Ospedali dei Colli, Via Leonardo Bianchi, 80131, Naples, Italy.
authors.forename: Antonio/A
authors.initials: A
authors.lastname: D'Onofrio
authors.affiliation: Department of Cardiology, Monaldi Hospital, AORN Ospedali dei Colli, Via Leonardo Bianchi, 80131, Naples, Italy.
authors.forename: Pio/P
authors.initials: P
authors.lastname: Caso
mesh_terms: D000368:Aged; D058406:Cardiac Resynchronization Therapy / Q000379:methods*; D058409:Cardiac Resynchronization Therapy Devices; D004452:Echocardiography; D006352:Heart Ventricles / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008297:Male; D012212:Rheology / Q000379:methods*; D016896:Treatment Outcome; D018487:Ventricular Dysfunction, Left / Q000175:diagnosis* / Q000503:physiopathology / Q000628:therapy*
keywords: CRT; Case report; Echo-PIV; Fluid dynamics; Quadripolar lead; RT3D-TTE; Vortex