Research

Yan TD, Tian DH, LeMaire SA, Misfeld M, Elefteriades JA, Chen EP, Hughes GC, Kazui T, Griepp RB, Kouchoukos NT, Bannon PG, Underwood MJ, Mohr FW, Oo A, Sundt TM, Bavaria JE, Di Bartolomeo R, Di Eusanio M, Roselli EE, Beyersdorf F, Carrel TP, Corvera JS, Della Corte A, Ehrlich M, Hoffman A, Jakob H, Matalanis G, Numata S, Patel HJ, Pochettino A, Safi HJ, Estrera A, Perreas KG, Sinatra R, Trimarchi S, Sun LZ, Tabata M, Wang C, Haverich A, Shrestha M, Okita Y, Coselli J

Eur J Cardiothorac Surg 2014 Jan;45(1):10-6

PMID: 24296985

Abstract

OBJECTIVE: A number of factors limit the effectiveness of current aortic arch studies in assessing optimal neuroprotection strategies, including insufficient patient numbers, heterogenous definitions of clinical variables, multiple technical strategies, inadequate reporting of surgical outcomes and a lack of collaborative effort. We have formed an international coalition of centres to provide more robust investigations into this topic.

METHODS: High-volume aortic arch centres were identified from the literature and contacted for recruitment. A Research Steering Committee of expert arch surgeons was convened to oversee the direction of the research.

RESULTS: The International Aortic Arch Surgery Study Group has been formed by 41 arch surgeons from 10 countries to better evaluate patient outcomes after aortic arch surgery. Several projects, including the establishment of a multi-institutional retrospective database, randomized controlled trials and a prospectively collected database, are currently underway.

CONCLUSIONS: Such a collaborative effort will herald a turning point in the surgical management of aortic arch pathologies and will provide better powered analyses to assess the impact of varying surgical techniques on mortality and morbidity, identify predictors for neurological and operative risk, formulate and validate risk predictor models and review long-term survival outcomes and quality-of-life after arch surgery.

Cooper EA, Edelman JJ, Black D, Brereton RJ, Ross DE, Bannon PG, Wilson MK, Vallely MP

Heart Lung Circ 2013 Dec;22(12):989-95

PMID: 23827207

Abstract

BACKGROUND: Elderly patients undergoing surgical revascularisation may disproportionately benefit from avoiding manipulation of the ascending aorta and cardiopulmonary bypass. In this multi-centre observational study, we sought to determine the 30-day outcomes of anaortic off-pump coronary artery bypass (OPCAB) in an elderly and very-elderly population.

METHODS: Data were prospectively collected for all patients aged >70 years old (y) undergoing anaortic OPCAB at three hospitals between January 2002 and October 2011. Analysis was carried out on two age sub-groups (70-79 y vs. ≥80 y). Multiple logistic regression was used to identify predictors of post-operative 30-day mortality.

RESULTS: In total, 1135 patients >70 years underwent anaortic OPCAB – 817 (72%) patients were aged 70-79 y while 318 (28%) were aged ≥80 y. The rate of mortality and morbidity for both groups was low: 30-day mortality (70-79 y: 1.8%; ≥80 y: 2.8%) or permanent stroke (70-79 y: 0.2%; ≥80 y: 0.9%). Chronic lung disease, a history of previous myocardial infarction and left main disease were independent predictors of 30-day mortality.

CONCLUSIONS: OPCAB is associated with low rates of 30-day mortality and peri-operative stroke in this elderly and very elderly patient cohort. Anaortic OPCAB can provide excellent short-term post-operative outcomes and may give the elderly and very elderly population the opportunity to benefit from surgical coronary revascularisation.

Edelman JJ, Teoh J, Okiwelu NL, Hung J, Passage J

J. Am. Coll. Cardiol. 2013 Oct;62(18):e243

PMID: 24013045

Abstract

Seco M, Cao C, Wilson MK, Vallely MP, Misfeld M, Mohr F, Yan TD

Ann Cardiothorac Surg 2013 Sep;2(5):678

PMID: 24109585

Abstract

Edelman JJ, Seco M, Dunne B, Matzelle SJ, Murphy M, Joshi P, Yan TD, Wilson MK, Bannon PG, Vallely MP, Passage J

Ann Cardiothorac Surg 2013 Sep;2(5):677

PMID: 24109584

Abstract

Wan B, Rahnavardi M, Tian DH, Bannon PG, Yan TD

Ann Cardiothorac Surg 2013 Sep;2(5):679

PMID: 24109586

Abstract

Vallely MP, Edelman JJ, Wilson MK

Ann Cardiothorac Surg 2013 Jul;2(4):570-7

PMID: 23977638

Abstract

Bilateral internal mammary artery (BIMA) grafts are used for coronary revascularisation by only a minority of surgeons, despite a growing body of evidence suggesting improved survival when compared to use of only one internal mammary artery with additional saphenous vein grafts. Herein we review the evidence supporting revascularisation with BIMA and suggest reasons why the majority of surgeons use only one internal mammary artery. We discuss technical considerations, various graft combinations and the use of BIMA to facilitate anaortic off-pump coronary artery bypass (OPCAB).

Byrom MJ, Ng MK, Bannon PG

Ann Cardiothorac Surg 2013 Jul;2(4):435-43

PMID: 23977620

Abstract

No currently available conduit meets the criteria for an ideal coronary artery bypass graft. The perfect conduit would combine the availability and complication-free harvest of a synthetic vessel with the long-term patency performance of the internal mammary artery. However, current polymer conduits suffer from inelastic mechanical properties and especially poor surface biocompatibility, resulting in early loss of patency as a coronary graft. Approaches to manufacture an improved conduit using new polymers or polymer surfaces, acellular matrices, or cellular constructs have to date failed to achieve a commercially successful alternative. Elastin, by mimicking the native extracellular environment as well as providing elasticity, provides the ‘missing link’ in vascular conduit design and brings new hope for realization of the perfect conduit.

Seco M, Edelman JJ, Yan TD, Wilson MK, Bannon PG, Vallely MP

Ann Cardiothorac Surg 2013 Jul;2(4):408-18

PMID: 23977616

Abstract

BACKGROUND: Advancements in surgical robotic technology over the last two decades have enabled coronary artery bypass grafting to be performed totally endoscopically, and have the potential to significantly change clinical practice in the future.

METHODS: A systematic review of studies reporting clinical outcomes of total endoscopic coronary artery bypass grafting (TECABG) was performed.

RESULTS: 14 appraised studies included 880 beating heart TECABGs, 360 arrested heart TECABGs, 633 one-vessel operations and 357 two-vessel operations. Patients were generally low-risk. There was a significant learning curve. The weighted means for short-term beating heart and arrested heart TECABG results respectively were: intraoperative exclusion rate of 5.7% and 1.9%, intraoperative conversion rate of 5.6% and 15.0%, all-cause mortality of 1.2% and 0.4%, stroke of 0.7% and 0.8%, myocardial infarction of 0.8% and 1.8%, new onset atrial fibrillation of 10.7% and 5.1% and post-operative reintervention rate of 2.6% and 2.3%. The overall rate of short term postoperative graft patency for beating heart and arrested heart TECABG was 98.3% and 96.4% respectively.

CONCLUSIONS: Appropriate patient selection was important in minimizing the risk of intraoperative and postoperative complications. Short-term outcomes of both beating and arrested heart TECABG were acceptable, but results so far have been heterogeneous. There were fewer studies reporting intermediate to long-term outcomes, but results were encouraging, and further investigation and development of the procedure is warranted.

Cao C, Ang SC, Wolak K, Peeceeyen S, Bannon P, Yan TD

Ann Cardiothorac Surg 2013 Jul;2(4):401-7

PMID: 23977615

Abstract

BACKGROUND: Currently, saphenous vein (SV) and radial artery (RA) are the most commonly used conduits in combination with the left internal mammary artery for conventional coronary artery bypass graft surgery (CABG). The present meta-analysis aimed to assess the existing evidence from randomized controlled trials (RCTs) to compare the angiographic outcomes of these two conduits at mid-term follow-up.

METHODS: Four relevant and updated RCTs with follow-up beyond 3 years were identified using five electronic databases. Angiographic endpoints included complete occlusion, ‘string sign’, graft failure and complete patency.

RESULTS: The incidence of complete occlusion was significantly lower after using RA compared to SV [6.7% vs. 17.2%; odd ratio (OR), 0.36; 95% confidence interval (CI), 0.23-0.58; P<0.0001]. The angiographic 'string sign' was significantly more likely to be identified after using RA compared to SV (3.1% vs. 0%; OR, 5.65; 95% CI, 1.21-26.39; P=0.03). Graft failure was significantly lower after RA compared to SV (9.6% vs. 18.8%; OR, 0.47; 95% CI, 0.30-0.72; P=0.0005). Complete graft patency was found to be significantly higher after RA compared to SV (88.6% vs. 75.8%; OR, 3.19; 95% CI, 1.42-7.16; P=0.005).

CONCLUSIONS: Results of the present meta-analysis suggest that selected patients with severe, proximal stenosis may have superior angiographic outcomes at mid-term follow-up after using RA compared to SV for CABG. However, RA is associated with a significantly higher incidence of the ‘string sign’. Future studies should aim to collect additional data on symptomatic outcomes.