SHORT TERM EVALUATION OF LEFT VENTRICULAR FUNCTION FOLLOWING DUAL CHAMBER PACEMAKER A SPECKLE TRACKING STUDY.

OBJECTIVE: Background:In 2012 the consensus issued by both the American College of Cardiology & Foundation Heart RhythmSociety Recommend the use of Dual Chamber Pace maker instead of Single chamber pace maker for patients withSinus Node dysfunction. Restoration of atrioventricular synchrony in patient with sinus node dysfunction orAtrioventricular block representing a new era in electrical therapy. the focus on normal physiology led to the nearly universal application of dual-chamber pacing to restore atrioventricular (AV) synchrony in patients with sinus rhythm.

DESIGN AND METHOD: Speckle tracking was used to evaluate the percent of ventricular deformation before and 3months follow upafter dual chamber implantation, this study included 28 patients with Sinus node dysfunction or Heart Failure-LBBB. This prospective observational study was carried out on patients of medical city, Baghdad Teaching Hospital, cardiology & Echocardiography Higher Education (Diploma) center from November 2016 to July 2017.

RESULTS: No statistical difference was noted between both gender groups in regard to main risk factors.Four methods were used to evaluate ventricular function synchrony (Ejection Fraction %, Global longitudinal stain, intraventricular synchrony using septal to posterior wall motion delay, interventricular Mechanical delay by Pulse wave), Global EF evaluated by Simpson biplane method remained the same in all patients after 3-month follow-up(P = NS). Global longitudinal strain (GLS) significantly decreased in all patients. Inter-ventricular dyssynchrony evaluation revealed no significant change after 3 months.

CONCLUSIONS: Global longitudinal strain and Left Ventricular dessynchrony assessment enables us to detect early signs of LV dysfunction in Subjects with dual chamber pacemaker.