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Background: The incidence of surgery for atrial fibrillation (AF) is rising, paralleled by an increase in the types of lesion sets and energy sources used. These alternate energy sources have simplified the surgery at the expense of increased cost of consumables. The classical Cox-Maze III is the gold standard therapy with a proven efficacy in curing AF. Our complete experience with this procedure is presented. Methods: All 28 patients undergoing the classical Cox-Maze III procedure at our institution underwent preoperative assessment and were followed prospectively. Results: Twenty-eight patients underwent the Cox-Maze III procedure between January 2001 and May 2003. Their mean age was 65 years (range, 44–80 years). Twenty-five patients had concomitant cardiac procedures. Mean duration of AF was 8.3 years. Permanent AF was present in 82%. Mean follow-up time was 15 ± 8 months (range, 4–30 months). There were no perioperative or late deaths, or thromboembolic events. Sixty-one per cent had early (<3 months) atrial arrhythmia. Freedom from AF at most recent clinical follow up was 93%. Freedom from late atrial arrhythmia was 82%. Freedom from late AF or atrial flutter by pacemaker interrogation or Holter assessment was 77%. Anti-arrhythmic medication use was reduced. New York Heart Association class improved from an average of 2.8 preoperatively to 1.3 postoperatively. Conclusion: The result of the present study shows the safety and efficacy of the classical Cox-Maze III procedure. With the advantage of proven long-term efficacy, demonstrable safety and avoidance of costly technology, the Cox-Maze III should not be discounted as a treatment option in patients because of its perceived complexity. [ABSTRACT FROM AUTHOR]

Allograft valves are a valuable valve replacement substitute in the surgical management of heart valve disease. It remains the valve substitute of choice in the reconstruction of the right ventricular outflow tract in children with congenital heart disease and in the Ross procedure. However, its durability remains suboptimal, particularly in children. This article reviews the mechanisms and factors implicated in late allograft dysfunction, with a focus on the evidence for an immunological cause for allograft failure. Unravelling the mechanisms of allograft valve failure may allow modification of the allograft to improve its long-term durability. [ABSTRACT FROM AUTHOR]

One of the features of diabetic vasculature is impaired vascular growth which leads on one hand to pathological increase in late diabetic eye disease and on the other to a decrease, as reflected by accelerated atherosclerosis and impaired wound healing. Tissues may be damaged not only by hyperglycaemia but also by various protein modifications including advanced glycation endproducts (AGEs). Aims of the project were to determine 1) effects of diabetes and 2) effects of high glucose and AGEs on vascular outgrowth using our novel in vitro model of adult human vascular growth. Briefly: Internal mammary artery fragments from 36 patients undergoing coronary artery bypass surgery (18 with Type 2 Diabetes and 18 non-diabetic controls) were cultured on fribrynogen matrix in alpha-MEM containing 10% FBS in 5% carbon dioxide for 2 weeks. For AGEs synthesis human serum albumin (HSA, 50mg/ml) was modified by incubation with 25mM of glucose for 8 weeks and added (100µg/ml) to the tissue culture. In other set of experiments effect of 25mM vs. 5mM glucose was evaluated. Vascular outgrowth was quantified by computerized image analysis system. Diabetic arteries showed two fold greater vascular outgrowth relative to non-diabetic arteries (n=13 pairs; p=0.02). Glucose modified HSA did not show any change in vascular outgrowth of non-diabetic explants (n=5). In 25mM glucose diabetic explant growth was inhibited 4-fold vs. growth in 5mM glucose (p<0.05) whilst growth of non-diabetic arteries was not impaired. In conclusions increased growth in Type 2 diabetic explants may reflect a compensatory up-regulation of arterial pro-angiogenic factors in vivo, that promotes growth once removed from a toxic milieu in vivo. High glucose inhibits vascular outgrowth of diabetic explants, but not non-diabetic arteries. This may reflect metabolic memory. Glucose-modified HSA does not adversely affect vascular growth. This model can be used for mechanistic studies and to test interventions. [ABSTRACT FROM AUTHOR]

Background: The Cox-Maze IV procedure is a proven surgical treatment for atrial fibrillation (AF). Previous studies on the procedure and its effect on left atrial mechanical function have yielded mixed results.Methods: Sixty-four (64) patients underwent Cox-Maze IV at St Vincent's Hospital, Melbourne between March 2010 and May 2016. Baseline characteristics were collected and outcomes assessed including rhythm analysis. Preoperative and postoperative transthoracic echocardiograms were reviewed.Results: Fifty-seven (57) patients had complete follow-up with all clinical measures collected. The mean age was 71.1±10.2years, 63% being male. Fifty-eight per cent (58%) (33/57) of patients were in AF and 42% (24/57) in sinus rhythm (SR) at preoperative transthoracic echocardiography. Follow-up postoperative transthoracic echocardiography was performed at a mean of 2.3±1.9years. Nineteen (19) patients with a history of paroxysmal AF were in SR both preoperatively and postoperatively. In these patients, there was a significant decrease in Mitral A wave 0.63±0.28m/s (pre-op) vs 0.47±0.29m/s (post-op), p=0.044. There was a significant decrease in left ventricular ejection fraction (LVEF) postoperatively 64.2±9.7% vs 55.0±12.9%, p=0.005. At follow-up, 28% (16/57) were in AF, 61% (35/57) in SR, and 11% (6/57) in a paced rhythm. In a multivariate analysis, predictors of AF recurrence included higher LA volumes (p=0.042) and younger age at surgery p=0.030. Preoperative AF, sex and LVEF had no impact on AF recurrence.Conclusions: The Cox-Maze IV procedure, while effective in converting patients to sinus rhythm, may reduce left atrial mechanical function in patients with paroxysmal AF. [ABSTRACT FROM AUTHOR]

The study compared cardiovascular risks factors, morbidity and in-hospital mortality following coronary artery bypass graft (CABG) surgery in Australian patients of different ethnic backgrounds including Aboriginal (AB), Italian (IT), Indian (IA), British Caucasians (BC), and Chinese (CH). These groups AB (n = 20), CH (n = 12), IT (n = 104), BC (n = 493), and IA (n = 16) all had first-time isolated CABG surgery at St. Vincent's Hospital, Melbourne from March 2001 to March 2007. AB patients were current or past smokers with the highest prevalence of preoperative diabetes (P = 0.001) and mostly had nonelective CABG surgery (P = 0.018). AB patients had higher incidences of postoperative respiratory failure (P = 0.001) compared with the other groups. In contrast, past history of MI (P = 0.012) was associated with IA patients. Both IA and AB groups had significantly higher acute renal failure rates requiring temporary dialysis (P = 0.025), longer ICU (P = 0.003) and hospital stays (P = 0.03) compared to BC, IT and CH groups. All groups had similar 30-day (P = 0.59) in-hospital mortality. The higher incidences of in-hospital morbidity observed in IA and AB compared to BC, IT, and CH groups suggests that ethnic lifestyle may be a strong risk factor. Larger confirmatory studies are required to verify incidents and elucidate reasons why ethnic-associated perioperative complications exist.

Idiopathic hypereosinophilic syndrome (HES) is an uncommon condition characterized by an unexplained elevation of absolute eosinophil count (AEC) to > or = 1.5 x 10(9)/l for at least six months, and is frequently associated with eosinophil-mediated end organ damage. Idiopathic HES, as with secondary HES and primary hypereosinophilic clonal hematopoietic disorders, has a high incidence of myocardial, pulmonary, neurological and other organ injury. Myocardial fibroelastosis and valvular lesions are common, and successful treatment with valve replacement or resection of fibrotic myocardium has been reported. The case is described of a patient with idiopathic HES and multi-organ complications including severe mitral valve disease, in whom a functionally obstructive thrombosis of a newly inserted prosthetic mitral valve occurred despite adequate anticoagulation, when the AEC was profoundly elevated. Recurrent thrombosis has not occurred over a substantial period following AEC reduction with corticosteroids, and subsequent maintenance at normal levels.

Unlabelled: The Australasian Society of Cardiac and Thoracic Surgeons (ASCTS) have established a database for the collection and analysis of the results of cardiac surgery in Australia and New Zealand. Initially data has been collected only in Victoria public hospitals. This report covers the first 12 months of data collection from 1st August 2001 to 1st July 2002., Background: Whilst cardiac surgical performance in Australia is considered to be of a high standard equivalent to other developed countries, there is currently no systematic approach to data collection in order to provide performance indicators and benchmarks. The development of an Australasian cardiac surgical database and performance indicators will enable benchmarking and comparison with international standards which should lead to performance improvements., Methods: A database definition set and standardised data collection form was developed by the ASCTS for all participating cardiac surgery units in public hospitals in Victoria. Opt-off consent for subject inclusion in the database was approved by each participating institutional ethics review committee. An electronic database and reporting application was developed. Data included in this analysis is from the initial 12 months collection from all hospitals participating in the project from 1st August 2001 to 31st July 2002., Results: Overall, there were 2982 procedures performed in this period of which 2969 had sufficient data to be included in this analysis (99.5%). The majority of procedures 2017 (68%) being undertaken were isolated coronary artery bypass surgery (CABG). The mean age of all subjects undergoing procedures was 65 years (range: 18-91 years) and 70% were male. 64% of all procedures were elective and 6.1% emergency or salvage. Median post-procedure length of hospital stay for all procedures was 6.0 days and intensive care unit (ICU) stay was 23.0h. Re-operation for haemorrhage occurred in 2.1% of all cases and deep sternal infection in 0.4% of all cases. Crude 30-day operative mortality was 3.6% for all procedures; 2.1% for isolated CABG, 3.6% for valve procedures, 5.2% for valve and CABG and 11.4% for other cardiac surgical procedures. Mortality rates increased from 1.8% for elective procedures to 4.1% for urgent and 24.6% for emergency or salvage operations. In comparison to international figures from the USA and UK, mortality rates following isolated CABG were lower whilst average length of hospital stay post-procedure was higher., Conclusion: The ASCTS database project is now well established and the electronic database and reporting module is in operation in all participating sites. The risk-adjusted isolated operative mortality suggests cardiac surgical performance in Victoria compares well with international standards. As the database develops, local risk-adjustment models for mortality and morbidity for each procedure will be developed to enable appropriate between hospital comparisons.