Clinical trial NCT00498940: Biventricular Pacing After Cardiopulmonary Bypass
Official title: Biventricular Pacing After Cardiopulmonary Bypass
Study type: INTERVENTIONAL
Overall status: TERMINATED
Phase: NA
Conditions: Heart Failure
Keywords: LV function, Compliance, wall motion, echocardiography
Lead sponsor: Columbia University
Sponsor class: OTHER
Collaborators: name: National Heart, Lung, and Blood Institute (NHLBI)
First posted: 2007-07-11
Enrollment: 111
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The purpose of this study is to investigate the efficacy of optimized temporary biventricular pacing (BiVP) in patients undergoing open-heart surgery with preoperative LV dysfunction and an intraventricular conduction delay. This study will compare extended temporary biventricular pacing versus standard of care by assessing patients randomized to the two groups, from the conclusion of cardiopulmonary bypass, until the conclusion of pharmacologic circulatory support in the intensive care unit. In addition, effects of biventricular pacing will be tested in all patients, at three time points, using different measures of blood flow. Results from this research will demonstrate whether temporary BiVP improves cardiac output after open-heart surgery and whether ventricular pacing optimization increases cardiac output in this setting. Success would lead to the development of recommendations for use of BiVP postoperatively and would stimulate the development of pacemakers with appropriate features.

The primary hypothesis is that the optimum pacing protocol (POPT) will increase cardiac index (CI) by 15% (from approximately 2.30 to 2.64 L/min/m2) compared to standard of care as measured by thermodilution 12-24 hours postoperatively. Secondary objectives include defining POPT at three time points within 24 hours of surgery. The investigator will examine which forms of cardiac dysfunction benefit from temporary pacing using direct and indirect measures of perfusion and cardiac function. The investigator will also analyze survival, length of stay, incidence of arrhythmias, and cost of postoperative care.

Detailed description: Biventricular pacing (BiVP) reverses intraventricular conduction delay (IVCD) and left ventricular (LV) dysfunction in dilated cardiomyopathy (DCM). BiVP improves LV function and cardiac index (Cl) at no energy cost. In the MIRACLE trial, in patients with DCM, IVCD and LV ejection fraction \<35%, demonstrated improved subjective and objective measures of exercise tolerance and cardiac function with BiVP. BiVP benefits many, but selection criteria are not fully developed, and 30% of recipients are "nonresponders," at a cost of more than $2 billion/year. Preliminary data suggest that BiVP can benefit patients with low output states after cardiac surgery. This study will assess surgical application of BiVP while assessing mechanisms of action and optimization. 190 cardiac surgery patients will be randomized with LV dysfunction preoperatively to paced and standard of care groups. BiVP will be optimized and continued postoperatively until patients are stable. BiVP will be assessed transiently in all patients at three time points. The primary end point is a 15% improvement in thermal dilution Cl measured in the intensive care unit (ICU). Effects of heart rate, atrioventricular delay, ventricular pacing site, and interventricular delay on Cl will be assessed using a randomized sequence of data collection. Secondary endpoints include incidence of arrhythmias, inotropic support, urine output, weight gain, morbidity, mortality, and ICU costs. These studies are important because of a high probability of clinical benefit. The methods employed will provide precision, breadth of measurement, and range of pacing sites superior to any other setting. The protocol will provide new and important scientific information that will benefit not only surgical patients but also the general population of BiVP recipients.

Eligibility criteria: Inclusion Criteria:

* LV ejection fraction \< 41%
* QRS duration \> 99 msec

Or:

* Mitral and Aortic Valve Repair or Replacement

Exclusion Criteria:

* Congenital Heart Disease
* Intracardiac Shunts
* Preoperative Pacing for Heart Block (2nd or 3rd degree) or Sinus Bradycardia
* Heart Rate \> 120 beats per min after Cardiopulmonary Bypass
* Preoperative Atrial Fibrillation
* Previous Cardiac Surgery
* Inability to undergo biventricular pacing prior to randomization

Primary outcomes:
measure: Thermal Dilution Cardiac Index (CI) Measured in the Intensive Care Unit (ICU).
timeFrame: 24 hours
Secondary outcomes:
measure: Number of Subjects With Postoperative Complications
timeFrame: 30 days after surgery
Other outcomes:
Locations:
city: New York
country: United States
facility: Columbia University
state: New York
Study officials:
affiliation: Professor
name: Henry M. Spotnitz, M.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Rubinstein BJ, Wang DY, Cabreriza SE, Cheng B, Aponte-Patel L, Murata A, Rusanov A, Richmond ME, Quinn TA, Spotnitz HM. Response of mean arterial pressure to temporary biventricular pacing after chest closure during cardiac surgery. J Thorac Cardiovasc Surg. 2012 Dec;144(6):1445-52. doi: 10.1016/j.jtcvs.2012.04.026. Epub 2012 Aug 21.