The Year in Cardiothoracic and Vascular Anesthesia: Selected Highlights from 2015

THIS ARTICLE IS the eighth in an annual series for the Journal of Cardiothoracic and Vascular Anesthesia.1Gutsche J.T. Pael P.A. Cobey F.C. et al.The year in cardiothoracic and vascular anesthesia: Selected highlights from 2014.J Cardiothorac Vasc Anesth. 2015; 29: 1-7Abstract Full Text Full Text PDF PubMed Scopus (1) Google Scholar The authors thank the editor-in-chief, Dr. Kaplan, and the editorial board for the opportunity to continue this series, namely the research highlights of the year that pertain to the specialty of cardiothoracic and vascular anesthesia. The major themes selected for this past year are outlined in this introduction, and each highlight is reviewed in detail in the main body of the article. The literature highlights in the specialty for 2015 begin with the mitral valve revolution.2Augoustides J.G. Atluri P. Progress in mitral valve disease: Understanding the revolution.J Cardiothorac Vasc Anesth. 2009; 23: 916-923Abstract Full Text Full Text PDF PubMed Scopus (13) Google Scholar Surgical intervention is now a reasonable option for asymptomatic severe mitral regurgitation. Recent landmark randomized trials from the Cardiothoracic Trials Surgical Network (CTSN) have further refined the surgical management of mitral valve disease. The role of transesophageal echocardiography (TEE) has remained central throughout these advances, especially now as transcatheter mitral interventions enter clinical practice. The second major theme in the specialty for 2015 is the development of temperature guidelines for the conduct of cardiopulmonary bypass for adult cardiac surgery. These guidelines likely will stimulate further trials to augment the evidence base and also focus attention on temperature management in specialized areas of cardiopulmonary bypass, such as hypothermic circulatory arrest. The third major theme for the specialty is the focus on the right ventricle with respect to clinical outcomes and echocardiography. The themes selected for this eighth highlights article are only a sample of the advances in the specialty during 2015. These highlights likely will further improve important perioperative outcomes for patients with cardiovascular disease. Mitral regurgitation (MR) remains a leading valve disease in the developed world, with an incidence that is likely to rise as the population ages.2Augoustides J.G. Atluri P. Progress in mitral valve disease: Understanding the revolution.J Cardiothorac Vasc Anesth. 2009; 23: 916-923Abstract Full Text Full Text PDF PubMed Scopus (13) Google Scholar, 3Nishimura R.A. Otto C.M. Bonow R.O. et al.2014 AHA/ACC guideline for the management of patients with valvular heart disease: executive summary—a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines.Circulation. 2014; 129: 2440-2492Crossref PubMed Scopus (1046) Google Scholar, 4Nkomo V.T. Gardin J.M. Skelton T.N. et al.Burden of valvular heart diseases: A population-based study.Lancet. 2006; 368: 1005-1011Abstract Full Text Full Text PDF PubMed Scopus (3128) Google Scholar The surgical management of MR has evolved progressively since being championed by Alain Carpentier in the 1970s and 1980s.3Nishimura R.A. Otto C.M. Bonow R.O. et al.2014 AHA/ACC guideline for the management of patients with valvular heart disease: executive summary—a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines.Circulation. 2014; 129: 2440-2492Crossref PubMed Scopus (1046) Google Scholar, 4Nkomo V.T. Gardin J.M. Skelton T.N. et al.Burden of valvular heart diseases: A population-based study.Lancet. 2006; 368: 1005-1011Abstract Full Text Full Text PDF PubMed Scopus (3128) Google Scholar, 5Woo Y.J. Mitral valve repair.Ann Cardiothorac Surg. 2015; 4: 219Google Scholar, 6Castillo J.G. Anyanwu A.C. Fuster V. et al.A near 100% repair rate for mitral valve prolapse is achievable in a reference center: Implications for future guidelines.J Thorac Cardiovasc Surg. 2012; 144: 308-312Abstract Full Text Full Text PDF PubMed Scopus (204) Google Scholar Mitral valve (MV) repair is now the preferred surgical intervention for MR and, in major referral centers, it can be accomplished in the majority of patients with minimal mortality in the setting of expert cardiac anesthesia and TEE.6Castillo J.G. Anyanwu A.C. Fuster V. et al.A near 100% repair rate for mitral valve prolapse is achievable in a reference center: Implications for future guidelines.J Thorac Cardiovasc Surg. 2012; 144: 308-312Abstract Full Text Full Text PDF PubMed Scopus (204) Google Scholar, 7Maslow A. Mitral valve repair: an echocardiographic review-part 1.J Cardiothorac Vasc Anesth. 2015; 29: 156-177Abstract Full Text Full Text PDF PubMed Scopus (21) Google Scholar, 8Maslow A. Mitral valve repair: an echocardiographic review-part 2.J Cardiothorac Vasc Anesth. 2015; 29: 439-471Abstract Full Text Full Text PDF PubMed Scopus (24) Google Scholar The MV revolution for MR now has progressed beyond the concept of MV repair to include the transcatheter era.9Maisano F. Alfieri O. Banai S. et al.The future of transcatheter mitral valve interventions: competitive or complementary role of repair vs. replacement?.Eur Heart J. 2015; 36: 1651-1659Crossref PubMed Scopus (149) Google Scholar The following examines this journey into new clinical realms, taking into account the latest clinical trials. Even though there is widespread agreement on the importance of surgical intervention in symptomatic patients with severe MR, there continues to be significant international disagreement regarding early surgical intervention for patients experiencing asymptomatic severe MR.5Woo Y.J. Mitral valve repair.Ann Cardiothorac Surg. 2015; 4: 219Google Scholar The American College of Cardiology/American Heart Association guidelines designate early MV surgery a class-IIa recommendation; whereas European guidelines are more conservative, with a class-IIb recommendation.3Nishimura R.A. Otto C.M. Bonow R.O. et al.2014 AHA/ACC guideline for the management of patients with valvular heart disease: executive summary—a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines.Circulation. 2014; 129: 2440-2492Crossref PubMed Scopus (1046) Google Scholar, 5Woo Y.J. Mitral valve repair.Ann Cardiothorac Surg. 2015; 4: 219Google Scholar, 10Vahanian A. Alfieri O. Andreotti F. et al.Guidelines on the management of valvular heart disease (version 2012).Eur Heart J. 2012; 33: 2451-2496Crossref PubMed Scopus (3182) Google Scholar Proponents for this early surgical approach of early intervention argue that the success rate of MV repair in experienced centers may prevent the deleterious effects of myocardial dysfunction due to severe MR.11Kang D.H. Park S.J. Sun B.J. et al.Early surgery versus conventional treatment for asymptomatic severe mitral regurgitation: A propensity analysis.J Am Coll Cardiol. 2014; 63: 2398-2407Abstract Full Text Full Text PDF PubMed Scopus (65) Google Scholar A recent meta-analysis demonstrated that early MV surgery compared with watchful waiting in patients experiencing asymptomatic, severe, degenerative MR significantly reduced all-cause mortality at 10 years (hazard ratio [HR] 0.38; 95% confidence interval [CI] 0.21-0.71), with no difference in rates of operative mortality (0.7% for both cohorts).12Goldstone A.B. Patrick W.L. Cohen J.E. et al.Early surgical intervention or watchful waiting for the management of asymptomatic mitral regurgitation: A systematic review and meta-analysis.Ann Cardiothorac Surg. 2015; 4: 220-229Google Scholar This survival benefit due to early MV surgery persisted in patients without atrial fibrillation or pulmonary hypertension, current class-II indicators for MV surgery in contemporary guidelines (relative risk [RR] 0.85; 95% CI 0.75-0.98).3Nishimura R.A. Otto C.M. Bonow R.O. et al.2014 AHA/ACC guideline for the management of patients with valvular heart disease: executive summary—a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines.Circulation. 2014; 129: 2440-2492Crossref PubMed Scopus (1046) Google Scholar, 10Vahanian A. Alfieri O. Andreotti F. et al.Guidelines on the management of valvular heart disease (version 2012).Eur Heart J. 2012; 33: 2451-2496Crossref PubMed Scopus (3182) Google Scholar, 12Goldstone A.B. Patrick W.L. Cohen J.E. et al.Early surgical intervention or watchful waiting for the management of asymptomatic mitral regurgitation: A systematic review and meta-analysis.Ann Cardiothorac Surg. 2015; 4: 220-229Google Scholar A further advantage of the early MV intervention paradigm is that it significantly increases the likelihood of MV repair (RR 1.10; 95% CI 1.02-1.18).12Goldstone A.B. Patrick W.L. Cohen J.E. et al.Early surgical intervention or watchful waiting for the management of asymptomatic mitral regurgitation: A systematic review and meta-analysis.Ann Cardiothorac Surg. 2015; 4: 220-229Google Scholar Further randomized trials are required to determine whether surgical intervention truly is indicated in patients experiencing asymptomatic, severe mitral regurgitation. This question is a possible opportunity for the CTSN. Aside from the success of MV repair in degenerative MR, the treatment of ischemic MR still remains controversial.3Nishimura R.A. Otto C.M. Bonow R.O. et al.2014 AHA/ACC guideline for the management of patients with valvular heart disease: executive summary—a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines.Circulation. 2014; 129: 2440-2492Crossref PubMed Scopus (1046) Google Scholar, 10Vahanian A. Alfieri O. Andreotti F. et al.Guidelines on the management of valvular heart disease (version 2012).Eur Heart J. 2012; 33: 2451-2496Crossref PubMed Scopus (3182) Google Scholar, 13Ramakrishna H. Ghadimi K. Augoustides J.G. Incidental moderate mitral regurgitation in patients undergoing coronary artery bypass grafting: Update on guidelines and key randomized trials.J Cardiothorac Vasc Anesth. 2014; 28: 189-193Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar The guidelines to date have been derived from an evidence base consisting of small observational and randomized studies that differed in design, study population, and definition of MR.13Ramakrishna H. Ghadimi K. Augoustides J.G. Incidental moderate mitral regurgitation in patients undergoing coronary artery bypass grafting: Update on guidelines and key randomized trials.J Cardiothorac Vasc Anesth. 2014; 28: 189-193Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar, 14Gulack B.C. Englum B.R. Castleberry A.W. et al.Repair or observe moderate ischemic mitral regurgitation during coronary artery bypass grafting? Prospective randomized multicenter data.Ann Cardiothorac Surg. 2015; 4: 266-272Google Scholar Results of 2 significant randomized trials were published in 2014 from the CTSN that provided further clarification.15Acker M.A. Parides M.K. Perrault L.P. et al.Mitral-valve repair versus replacement for severe ischemic mitral regurgitation.N Engl J Med. 2014; 370: 23-32Crossref PubMed Scopus (634) Google Scholar, 16Smith P.K. Puskas J.D. Ascheim D.D. et al.Surgical treatment of moderate ischemic mitral regurgitation.N Engl J Med. 2014; 371: 2178-2188Crossref PubMed Scopus (295) Google Scholar Acker et al examined the impact of MV repair versus replacement for severe ischemic MR in 251 patients.15Acker M.A. Parides M.K. Perrault L.P. et al.Mitral-valve repair versus replacement for severe ischemic mitral regurgitation.N Engl J Med. 2014; 370: 23-32Crossref PubMed Scopus (634) Google Scholar No significant differences in left ventricular (LV) reverse remodeling or survival were noted at 12 months.15Acker M.A. Parides M.K. Perrault L.P. et al.Mitral-valve repair versus replacement for severe ischemic mitral regurgitation.N Engl J Med. 2014; 370: 23-32Crossref PubMed Scopus (634) Google Scholar The recurrence of moderate or greater MR at 12 months was significantly higher for MV repair compared with replacement (32.6% v 2.3%: p<0.001).15Acker M.A. Parides M.K. Perrault L.P. et al.Mitral-valve repair versus replacement for severe ischemic mitral regurgitation.N Engl J Med. 2014; 370: 23-32Crossref PubMed Scopus (634) Google Scholar The main mechanism for failure of MV repair in this key randomized trial was ongoing MV leaflet tethering.17Kron L. Hung J. Overbey J.R. et al.Predicting recurrent mitral regurgitation after mitral valve repair for severe ischemic mitral regurgitation.J Thorac Cardiovasc Surg. 2015; 149: 752-761Abstract Full Text Full Text PDF PubMed Scopus (156) Google Scholar Although a multivariate model was derived to predict the risk of recurrent MR in this setting, there already has been a call for a more definitive surgical approach for MV repair in ischemic MR.17Kron L. Hung J. Overbey J.R. et al.Predicting recurrent mitral regurgitation after mitral valve repair for severe ischemic mitral regurgitation.J Thorac Cardiovasc Surg. 2015; 149: 752-761Abstract Full Text Full Text PDF PubMed Scopus (156) Google Scholar, 18Kron I.L. Perrault L.P. Acker M.A. We need a better way to repair ischemic mitral regurgitation.J Thorac Cardiovasc Surg. 2015; 150: 428Abstract Full Text Full Text PDF Scopus (6) Google Scholar In patients with both moderate MR and coronary artery disease, the decision to perform both coronary artery bypass grafting (CABG) and correction of moderate MR has remained unclear.13Ramakrishna H. Ghadimi K. Augoustides J.G. Incidental moderate mitral regurgitation in patients undergoing coronary artery bypass grafting: Update on guidelines and key randomized trials.J Cardiothorac Vasc Anesth. 2014; 28: 189-193Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar, 14Gulack B.C. Englum B.R. Castleberry A.W. et al.Repair or observe moderate ischemic mitral regurgitation during coronary artery bypass grafting? Prospective randomized multicenter data.Ann Cardiothorac Surg. 2015; 4: 266-272Google Scholar In the largest prospective randomized trial to date, the Surgical Treatment of Moderate Ischemic Mitral Regurgitation Trial, Smith et al randomly assigned 301 patients with moderate ischemic MR at 26 sites to CABG alone or CABG plus MV repair.16Smith P.K. Puskas J.D. Ascheim D.D. et al.Surgical treatment of moderate ischemic mitral regurgitation.N Engl J Med. 2014; 371: 2178-2188Crossref PubMed Scopus (295) Google Scholar The primary endpoint was the left ventricular end-systolic volume index at 1 year. In patients with moderate ischemic MR, the combination of MV repair and CABG did not result in a higher degree of LV reverse remodeling as reflected by the left ventricular end-systolic volume index (z score 0.50; p = 0.61), although the risk of recurrent significant MR was significantly lower in the MV repair cohort (11.2% v 31%; p<0.001).16Smith P.K. Puskas J.D. Ascheim D.D. et al.Surgical treatment of moderate ischemic mitral regurgitation.N Engl J Med. 2014; 371: 2178-2188Crossref PubMed Scopus (295) Google Scholar Even though MV repair resulted in a reduced risk of downstream MR, it was associated with longer cardiopulmonary bypass (CPB) times (p<0.001), longer hospital stays after surgery (p<0.002), and more neurologic events (p<0.03).16Smith P.K. Puskas J.D. Ascheim D.D. et al.Surgical treatment of moderate ischemic mitral regurgitation.N Engl J Med. 2014; 371: 2178-2188Crossref PubMed Scopus (295) Google Scholar At 1 year, the investigators concluded that there was no meaningful advantage to adding MV repair to CABG in patients with incidental moderate MR. Further clinical monitoring of this CTSN trial cohort may demonstrate a net outcome advantage due to reduced downstream MR associated with MV repair.13Ramakrishna H. Ghadimi K. Augoustides J.G. Incidental moderate mitral regurgitation in patients undergoing coronary artery bypass grafting: Update on guidelines and key randomized trials.J Cardiothorac Vasc Anesth. 2014; 28: 189-193Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar, 14Gulack B.C. Englum B.R. Castleberry A.W. et al.Repair or observe moderate ischemic mitral regurgitation during coronary artery bypass grafting? Prospective randomized multicenter data.Ann Cardiothorac Surg. 2015; 4: 266-272Google Scholar, 16Smith P.K. Puskas J.D. Ascheim D.D. et al.Surgical treatment of moderate ischemic mitral regurgitation.N Engl J Med. 2014; 371: 2178-2188Crossref PubMed Scopus (295) Google Scholar A third CTSN trial in patients presenting for MV surgery examined the role of surgical ablation for concomitant atrial fibrillation in this setting.19Gillinov A.M. Gelijns A.C. Parides M.K. et al.Surgical ablation of atrial fibrillation during mitral-valve surgery.N Engl J Med. 2015; 372: 1399-1409Crossref PubMed Scopus (292) Google Scholar Atrial fibrillation has a prevalence of 30% to 50% in this population and has important outcome effects, such as reduced survival, stroke, and significant economic burden.20Raiten J.M. Ghadimi K. Augoustides J.G. et al.Atrial fibrillation after cardiac surgery: clinical update and prophylactic strategies.J Cardiothorac Vasc Anesth. 2015; 29: 806-816Abstract Full Text Full Text PDF PubMed Scopus (41) Google Scholar, 21Bhatt H.V. Fischer G.W. Atrial fibrillation: pathophysiology and therapeutic options.J Cardiothorac Vasc Anesth. 2015 May 8; ([Epub ahead of print])Google Scholar, 22Rostagno C. La Meir M. Gelsomino S. et al.Atrial fibrillation after cardiac surgery: Incidence, risk factors and economic burden.J Cardiothorac Vasc Anesth. 2010; 24: 952-958Abstract Full Text Full Text PDF PubMed Scopus (65) Google Scholar, 23Lomivorotov VV, Efremov SM, Pokushalov EA, et al: Newonset atrial fibrillation after cardiac surgery: Pathophysiology, prophy laxis, and treatment. J Cardiothorac Vasc Anesth : [Epub ahead of print], 2015. http://dx.doi.org/10.1053/j.jvca.2015.08.003Google Scholar Given that atrial fibrillation is common and important, it hardly is surprising that the CTSN chose it for this randomized trial in which a cohort of 260 patients with chronic atrial fibrillation presenting for MV surgery were randomized with respect to surgical ablation.19Gillinov A.M. Gelijns A.C. Parides M.K. et al.Surgical ablation of atrial fibrillation during mitral-valve surgery.N Engl J Med. 2015; 372: 1399-1409Crossref PubMed Scopus (292) Google Scholar Furthermore, all patients underwent left atrial appendage ligation, and the ablation cohort further was assigned randomly to pulmonary vein isolation versus a biatrial maze procedure.19Gillinov A.M. Gelijns A.C. Parides M.K. et al.Surgical ablation of atrial fibrillation during mitral-valve surgery.N Engl J Med. 2015; 372: 1399-1409Crossref PubMed Scopus (292) Google Scholar The primary trial endpoint was freedom from atrial fibrillation in the first year as detected by 3-day Holter monitoring.19Gillinov A.M. Gelijns A.C. Parides M.K. et al.Surgical ablation of atrial fibrillation during mitral-valve surgery.N Engl J Med. 2015; 372: 1399-1409Crossref PubMed Scopus (292) Google Scholar Freedom from atrial fibrillation in the first year was significantly enhanced by surgical ablation (63.2% v 29.4%; p<0.001). Furthermore, simple pulmonary vein isolation was as effective as an extensive biatrial maze procedure in providing freedom from atrial fibrillation (61% v 66%; p = 0.60). Although concomitant surgical ablation added no additional outcome risk including mortality (HR 0.76; 95% CI 0.32-1.84; p = 0.56), it did significantly increase the risk for a permanent pacemaker (21.5 v 8.1 per 100 patient years; p = 0.01).19Gillinov A.M. Gelijns A.C. Parides M.K. et al.Surgical ablation of atrial fibrillation during mitral-valve surgery.N Engl J Med. 2015; 372: 1399-1409Crossref PubMed Scopus (292) Google Scholar In summary, these 3 recent randomized trials from the CTSN significantly have enhanced the surgical management of patients with significant MR. Given the controversy surrounding asymptomatic degenerative MR, this management decision may lend itself to a landmark randomized CTSN trial, as outlined earlier. As reflected in both European and American valvular heart disease recent guidelines, there remains inconclusive evidence to guide the surgical management of significant secondary MR.3Nishimura R.A. Otto C.M. Bonow R.O. et al.2014 AHA/ACC guideline for the management of patients with valvular heart disease: executive summary—a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines.Circulation. 2014; 129: 2440-2492Crossref PubMed Scopus (1046) Google Scholar, 10Vahanian A. Alfieri O. Andreotti F. et al.Guidelines on the management of valvular heart disease (version 2012).Eur Heart J. 2012; 33: 2451-2496Crossref PubMed Scopus (3182) Google Scholar Transcatheter mitral techniques may offer expanded treatment options in high-risk cohorts with significant MV disease.9Maisano F. Alfieri O. Banai S. et al.The future of transcatheter mitral valve interventions: competitive or complementary role of repair vs. replacement?.Eur Heart J. 2015; 36: 1651-1659Crossref PubMed Scopus (149) Google Scholar, 24Arsalan M. Squiers J.J. DiMaio J.M. et al.Catheter-based or surgical repair of the highest risk secondary mitral regurgitation patients.Ann Cardiothorac Surg. 2015; 4: 278-283Google Scholar Although transcatheter devices have borrowed the principles of surgical MV repair, they now include techniques for leaflet resection, neochordal construction, annuloplasty, and edge-to-edge leaflet approximation that have spawned a family of randomized trials with defined endpoints.2Augoustides J.G. Atluri P. Progress in mitral valve disease: Understanding the revolution.J Cardiothorac Vasc Anesth. 2009; 23: 916-923Abstract Full Text Full Text PDF PubMed Scopus (13) Google Scholar, 25Ruiz C.E. Kliger C. Perk C. et al.Transcatheter therapies for the treatment of valvular and paravalvular regurgitation in acquired and congenital valvular heart disease.J Am Coll Cardiol. 2015; 66: 169-183Abstract Full Text Full Text PDF PubMed Scopus (23) Google Scholar, 26Stone G.W. Vahanian A. Adams D.H. et al.Clinical trial design and endpoint definitions for transcatheter mitral valve repair and replacement: part 1: Clinical trial design principles. A consensus document from the Mitral Valve Academic Research Consortium.J Am Coll Cardiol. 2015; 66: 278-307Abstract Full Text Full Text PDF PubMed Scopus (146) Google Scholar, 27Stone G.W. Adams D.H. Abraham W.T. et al.Clinical trial design principles and endpoint definitions for transcatheter mitral valve repair and replacement: Part 2: Endpoint definitions. A consensus statement from the Mitral Valve Academic Research Consortium.J Am Coll Cardiol. 2015; 66: 308-321Abstract Full Text Full Text PDF PubMed Scopus (301) Google Scholar While there are multiple devices currently in trials for feasibility, the MitraClip device (Abbott, Abbott Park, IL), modeled after the surgical edge-to-edge repair (Alfieri stitch), has been used extensively with more than 19,000 applications worldwide.9Maisano F. Alfieri O. Banai S. et al.The future of transcatheter mitral valve interventions: competitive or complementary role of repair vs. replacement?.Eur Heart J. 2015; 36: 1651-1659Crossref PubMed Scopus (149) Google Scholar, 24Arsalan M. Squiers J.J. DiMaio J.M. et al.Catheter-based or surgical repair of the highest risk secondary mitral regurgitation patients.Ann Cardiothorac Surg. 2015; 4: 278-283Google Scholar A randomized trial that evaluated MitraClip in degenerative MR resulted in commercial approval of the device in the United States in 2013.28Feldman T. Foster E. Glower D.D. et al.Percutaneous repair or surgery for mitral regurgitation.N Engl J Med. 2011; 364: 1395-1406Crossref PubMed Scopus (1475) Google Scholar, 29Di Prima A.L. Covello D.R. Franco A. et al.Do patients undergoing MitraClip implantation require routine ICU admission?.J Cardiothorac Vasc Anesth. 2014; 28: 1479-1483Abstract Full Text Full Text PDF Scopus (16) Google Scholar The anesthetic approach for this procedure already has been discussed extensively in the Journal.29Di Prima A.L. Covello D.R. Franco A. et al.Do patients undergoing MitraClip implantation require routine ICU admission?.J Cardiothorac Vasc Anesth. 2014; 28: 1479-1483Abstract Full Text Full Text PDF Scopus (16) Google Scholar, 30Hayman M. Forrest P. Kam P. Anesthesia for interventional cardiology.J Cardiothorac Vasc Anesth. 2012; 28: 134-147Abstract Full Text Full Text PDF Scopus (12) Google Scholar The Endovascular Valve Edge-to-Edge Repair Study (EVEREST) II randomly assigned 279 patients with severe degenerative MR to transcatheter MitraClip repair or open surgical repair.28Feldman T. Foster E. Glower D.D. et al.Percutaneous repair or surgery for mitral regurgitation.N Engl J Med. 2011; 364: 1395-1406Crossref PubMed Scopus (1475) Google Scholar The primary trial endpoint for efficacy was a composite of freedom from the following 3 outcomes at 12 months: death, MV surgery, and severe MR.28Feldman T. Foster E. Glower D.D. et al.Percutaneous repair or surgery for mitral regurgitation.N Engl J Med. 2011; 364: 1395-1406Crossref PubMed Scopus (1475) Google Scholar The primary trial endpoint for safety was a composite of major adverse events by 30 days.28Feldman T. Foster E. Glower D.D. et al.Percutaneous repair or surgery for mitral regurgitation.N Engl J Med. 2011; 364: 1395-1406Crossref PubMed Scopus (1475) Google Scholar The efficacy endpoint was significantly lower in the transcatheter cohort (55% v 73%; p = 0.007), with the following individual outcome comparisons: death (6% in each cohort), MV surgery (20% v 2%), and severe MR (21% v 20%).28Feldman T. Foster E. Glower D.D. et al.Percutaneous repair or surgery for mitral regurgitation.N Engl J Med. 2011; 364: 1395-1406Crossref PubMed Scopus (1475) Google Scholar The safety endpoint was significantly better in the transcatheter cohort (15% v 48% for major adverse events at 30 days; p<0.001).28Feldman T. Foster E. Glower D.D. et al.Percutaneous repair or surgery for mitral regurgitation.N Engl J Med. 2011; 364: 1395-1406Crossref PubMed Scopus (1475) Google Scholar The investigators concluded that percutaneous MV repair with MitraClip compared with surgical repair was safer and resulted in similar outcomes, although it was less effective at reducing MR.28Feldman T. Foster E. Glower D.D. et al.Percutaneous repair or surgery for mitral regurgitation.N Engl J Med. 2011; 364: 1395-1406Crossref PubMed Scopus (1475) Google Scholar The medium-term follow-up trial demonstrated that after the first year, MV surgery was rare in either cohort and that, after 4 years, the rates of mortality and severe MR were similar in both cohorts.31Mauri L. Foster E. Glower D.D. et al.4-year results of a randomized controlled trial of percutaneous repair versus surgery for mitral regurgitation.J Am Coll Cardiol. 2013; 62: 317-328Abstract Full Text Full Text PDF PubMed Scopus (334) Google Scholar Even though the MitraClip has shown favorable results in large European registries, it only has approval in the United States for high-risk patients with MR.32O’Gara P.T. Calhoon J.H. Moon M.R. et al.Transcatheter therapies for mitral regurgitation: A professional society overview from the American College of Cardiology, The American Association for Thoracic Surgery, Society for Cardiovascular Angiography and Interventions Foundation, and The Society of Thoracic Surgeons.J Thorac Cardiovasc Surg. 2014; 147: 837-849Abstract Full Text Full Text PDF PubMed Scopus (7) Google Scholar The 2014 American College of Cardiology/American Heart Association valve guidelines designate a class-IIb recommendation for MitraClip in symptomatic patients with severe primary MR at high risk for conventional MV surgery.3Nishimura R.A. Otto C.M. Bonow R.O. et al.2014 AHA/ACC guideline for the management of patients with valvular heart disease: executive summary—a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines.Circulation. 2014; 129: 2440-2492Crossref PubMed Scopus (1046) Google Scholar Currently, 3 large, randomized, clinical trials are in progress to clarify the role of transcatheter devices in secondary MR.32O’Gara P.T. Calhoon J.H. Moon M.R. et al.Transcatheter therapies for mitral regurgitation: A professional society overview from the American College of Cardiology, The American Association for Thoracic Surgery, Society for Cardiovascular Angiography and Interventions Foundation, and The Society of Thoracic Surgeons.J Thorac Cardiovasc Surg. 2014; 147: 837-849Abstract Full Text Full Text PDF PubMed Scopus (7) Google Scholar Recent multisociety professional guidelines have aimed to ensure the appropriate integration of transcatheter MR therapies into daily practice.26Stone G.W. Vahanian A. Adams D.H. et al.Clinical trial design and endpoint definitions for transcatheter mitral valve repair and replacement: part 1: Clinical trial design principles. A consensus document from the Mitral Valve Academic Research Consortium.J Am Coll Cardiol. 2015; 66: 278-307Abstract Full Text Full Text PDF PubMed Scopus (146) Google Scholar, 27Stone G.W. Adams D.H. Abraham W.T. et al.Clinical trial design principles and endpoint definitions for transcatheter mitral valve repair and replacement: Part 2: Endpoint definitions. A consensus statement from the Mitral Valve Academic Research Consortium.J Am Coll Cardiol. 2015; 66: 308-321Abstract Full Text Full Text PDF PubMed Scopus (301) Google Scholar, 32O’Gara P.T. Calhoon J.H. Moon M.R. et al.Transcatheter therapies for mitral regurgitation: A professional society overview from the American College of Cardiology, The American Association for Thoracic Surgery, Society for Cardiovascular Angiography and Inter