Clinical trial NCT02842762: 3D Echocardiographic Assessment of Epicardial Pacing After Cardiopulmonary Bypass.
Official title: The Hemodynamic Effect of Transient Epicardial Right Ventricular Pacing After Cardiopulmonary Bypass, Assessed by Real-time Three-dimensional Echocardiography.
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Disorder of Pacing Function
Keywords: Echocardiography, Three-dimensional
Cardiac Surgical Procedures
Cardiac Pacing, Artificial
Anesthesia
Lead sponsor: London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's
Sponsor class: OTHER
First posted: 2016-07-25
Enrollment: 40
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: Sequence of measurements, during sinus rhythm and during pacing is randomized.
Primary purpose: DIAGNOSTIC

Brief summary: This study evaluates the usefulness of 3D echocardiography to guide pacemaker therapy in the operating room in cardiac surgical patients. Each patient will serve as his own control, following a paired design.

Detailed description: Cardiac surgical patients sometimes require temporary pacing wires to optimize cardiac function during weaning from cardiopulmonary bypass (CPB), and/or to treat hemodynamically significant brady-arrhythmias. The available patient series report that 8.6% to 23.9% of patient undergoing coronary artery bypass grafting (CABG) or valve surgery require temporary pacing at some time after CPB. The site of pacemaker wire placement seems to be a crucial determinant of cardiac output. In non-surgical patients isolated right ventricular (RV) pacing seems to induce electromechanical dyssynchrony of the RV and the left ventricle (LV). A normal ventricle in sinus rhythm displays a simultaneous contraction of all segments of the heart, so that regional minimal volume (i.e. maximal contraction) will occur at the same time. Isolated RV pacing seems to result in a left bundle branch type electrical activation sequence, with delayed contraction of some of the segments. The LV, but not the RV, seems to negatively affected by this state of dyssynchrony, resulting in decreased cardiac output. In surgical patients however, there is not such data available yet. Since isolated RV epicardial wire placement is still widely practiced in cardiac surgery, and in our own institution, we would like to study the effect of RV pacing on LV synchrony and LV output.

Again from studies in non-surgical patients receiving resynchronization therapy, we know that real-time three-dimensional (3D) echocardiography is very useful to pick up subtle changes in LV synchrony and thereby guide synchronization of ventricular contraction. However, to date the usefulness of real-time 3D echocardiography to guide pacemaker therapy in cardiac surgery is unknown. In the present feasibility study in cardiac surgical patients, we want to investigate the acute effects of isolated RV pacing on LV synchrony, and LV output.

Eligibility criteria: Inclusion Criteria:

* Adult patient scheduled to undergo elective cardiac surgery by means of full sternotomy and use of cardiopulmonary bypass
* Preoperative moderate to good LV function, ejection fraction \> 30%
* Age \> 18 yrs. old
* Preoperative sinus rhythm
* Pacemaker lead inserted by cardiac surgeon during surgery
* Underlying sinus rhythm after cardiopulmonary bypass before the end of surgery
* Able to understand written and verbal patient information
* Signed informed consent

Exclusion Criteria:

* Emergency cardiac surgery
* Minimally invasive surgery
* Contraindication to TEE
* Redo surgery
* Hemodynamic instability after CPB (late exclusion criterium)
* No pacemaker lead inserted by cardiac surgeon (late exclusion criterium)
* No sinus rhythm during chest closure towards the end of surgery (late exclusion criterium)

Primary outcomes:
measure: Left ventricular systolic dyssynchrony index (SDI)
timeFrame: Intraoperative, end of cardiac surgery (duration 10 minutes)
Secondary outcomes:
measure: Ventricular volumes and ejection fraction
timeFrame: Intraoperative, end of cardiac surgery (duration 10 minutes)
measure: LVOT blood flow
timeFrame: Intraoperative, end of cardiac surgery (duration 10 minutes)
measure: Presence and severity of mitral regurgitation
timeFrame: Intraoperative, end of cardiac surgery (duration 10 minutes)
Other outcomes:
Locations:
city: London
country: Canada
facility: University Hospital - London Health Sciences Centre
state: Ontario
Study officials:
affiliation: London Health Sciences Center
name: Suzanne Flier, MD MSc
role: PRINCIPAL_INVESTIGATOR
References:
citation: Wolber T, Haegeli L, Huerlimann D, Brunckhorst C, Luscher TF, Duru F. Altered left ventricular contraction pattern during right ventricular pacing: assessment using real-time three-dimensional echocardiography. Pacing Clin Electrophysiol. 2011 Jan;34(1):76-81. doi: 10.1111/j.1540-8159.2010.02908.x. Epub 2010 Oct 14.
citation: Kapetanakis S, Kearney MT, Siva A, Gall N, Cooklin M, Monaghan MJ. Real-time three-dimensional echocardiography: a novel technique to quantify global left ventricular mechanical dyssynchrony. Circulation. 2005 Aug 16;112(7):992-1000. doi: 10.1161/CIRCULATIONAHA.104.474445. Epub 2005 Aug 8.
citation: Alwaqfi NR, Ibrahim KS, Khader YS, Baker AA. Predictors of temporary epicardial pacing wires use after valve surgery. J Cardiothorac Surg. 2014 Feb 12;9:33. doi: 10.1186/1749-8090-9-33.
citation: Bethea BT, Salazar JD, Grega MA, Doty JR, Fitton TP, Alejo DE, Borowicz LM Jr, Gott VL, Sussman MS, Baumgartner WA. Determining the utility of temporary pacing wires after coronary artery bypass surgery. Ann Thorac Surg. 2005 Jan;79(1):104-7. doi: 10.1016/j.athoracsur.2004.06.087.