Cardiothoracic Surgical Trials Network (CTSN)
Parent Study Contact: Albert Lee, firstname.lastname@example.org
Study Type: Clinical Trial
Prepared on July 10, 2012
Consent: Restricted Consent
Consent Restrictions: For protocol use only
Commercial Use Restrictions: Yes
Collection Type: Proprietary Study - See bottom of this webpage for request information
The CTSN conducts multiple collaborative proof-of-concept studies and interventional protocols to improve cardiovascular disease outcomes.
Surgical Ablation versus No Surgical Ablation for Patients with Persistent or Longstanding Persistent Atrial Fibrillation Undergoing Mitral Valve Surgery (CTSN-Afib)
The purpose of the research is to determine if surgical ablation for persistent or longstanding persistent atrial fibrillation (AF) is more effective than mitral valve surgery alone in reducing the occurrence of AF after mitral valve surgery. Both mitral valve surgery and surgical ablation have been used regularly in patients who have mitral valve problems and atrial fibrillation. Current understanding in the pathogenesis of AF and new tissue ablation technologies focuses on creating lines of conduction block which have laid the foundation for widespread attempts at AF ablation during heart surgery. The pulmonary veins and left atrium house the triggers, drivers, and substrate for atrial fibrillation (AF) in most patients, and ablation strategies are directed to these structures. While surgical pulmonary vein isolation (PVI) is widely employed, several lines of evidence also suggest that a complex biatrial lesion set, such as the Cox-Maze III, may enhance ablation effectiveness. However, prior studies have been insufficiently powered to establish the effectiveness of surgical ablation compared to mitral valve surgery alone. Thus, the goal of this study is to resolve this question in patients with persistent or longstanding persistent AF. For patients undergoing surgical ablation, they will be randomized to receive either PVI or a biatrial lesion set. All patients in this study will undergo ligation or excision of the left atrial appendage.
Surgical Interventions for Moderate Ischemic Mitral Regurgitation (CTSN-MMR)
The purpose of the research is to determine whether repairing a mitral valve with moderate leakage (regurgitation), at the time of planned coronary artery bypass graft (CABG) surgery, will improve health outcomes of those who receive it compared to those who have the bypass alone. Ischemic or functional mitral regurgitation is not a structural valve problem but is rather characterized by geometric alterations of the left ventricle that may be global or regional. Global progressive left ventricle dilatation results in lateral displacement of the papillary muscles combined with dilation of the mitral valve annulus, leading to failure of the mitral valve leaflets to coapt, and a central jet of mitral regurgitation (MR). Regional wall motion abnormalities can result in asymmetric leaflet coaptation, progressive MR, secondary global left ventricle dilatation and heart failure. Both regional and global changes may respond to CABG, but the degree to which this can stabilize or reverse associated MR is unpredictable. Treatment selection for coronary artery disease with IMR has become increasingly controversial, with patients being treated with coronary bypass grafting (CABG) and mitral valve repair/replacement, or with CABG alone. This study evaluates whether patients with moderate mitral valve leakage would be better off undergoing CABG plus the mitral valve repair procedure, or undergoing CABG alone.
Evaluation of Outcomes Following Mitral Valve Repair versus Replacement in Severe Chronic Ischemic Mitral Regurgitation (CTSN-SMR)
The purpose of this research is to determine whether it is better to replace or repair the mitral valve of patients with severe mitral valve leakage (regurgitation) from coronary artery disease. Post-infarction changes in ventricular structure and function often create ischemic mitral regurgitation (MR) secondary to two distinct processes. Locally, inferior and posterior remodeling causes displacement of the papillary muscles away from the mitral valve annulus, promoting leaflet tethering and restriction of motion, which inhibits coaptation. Globally, annular enlargement secondary to left ventricular (LV) dilatation causes central malcoaptation which is compounded by LV dysfunction. Several studies have compared replacement to repair in patients with severe MR, but considerable controversy remains regarding optimal surgical strategies for these patients. In this study, mitral valve replacement includes complete preservation of the subvalvar apparatus. For mitral valve repair, an annuloplasty ring will be chosen by the surgeon. The ring is sized to the anterior leaflet and intertrigonal distance. A semi-rigid or rigid annuloplasty ring will be used. If tethering is present, a subvalvar procedure may be performed. This study will evaluate whether it is better for people with severe mitral valve leakage to undergo a mitral valve replacement procedure or a mitral valve repair procedure.