Comorbidities and Ventricular Dysfunction Drive Excess Mid-Term Morbidity in an Indigenous Australian Coronary Revascularisation Cohort.

BACKGROUND: There is a paucity of data in regards to longer term morbidity outcomes in Indigenous Australian patients undergoing coronary artery bypass grafting (CABG). No comparative data on re-infarction, stroke or reintervention rates exist. Outcome data following percutaneous coronary intervention (PCI) is also extremely limited. Addressing this gap in knowledge forms the major aim of our study. METHODS: This was a single centre cohort study conducted at the Townsville Hospital, Australia which provides tertiary adult cardiac surgical services to the northern parts of the state of Queensland. It incorporated consecutive patients (n=350) undergoing isolated CABG procedures, 2008-2010, 20.9% (73/350) of whom were Indigenous Australians. The main outcome measures were major adverse cardiac or cerebrovascular events (MACCE) at mid-term follow-up (mean 38.9 months). RESULTS: The incidence of MACCE among Indigenous Australian patients was approximately twice that of non-Indigenous patients at mid-term follow-up (36.7% vs. 18.6%; p=0.005; OR 2.525 (1.291-4.880)). Following adjustment for preoperative and operative variables, Indigenous Australian status itself was not significantly associated with MACCE (AOR 1.578 (0.637-3.910)). Significant associations with MACCE included renal impairment (AOR 2.198 (1.010-4.783)) and moderate-severe left ventricular impairment (AOR 3.697 (1.820-7.508)). An association between diabetes and MACCE failed to reach statistical significance (AOR 1.812 (0.941-3.490)). CONCLUSIONS: Indigenous Australians undergoing CABG suffer an excess of MACCE when followed-up in the longer term. High rates of comorbidities in the Indigenous Australian population likely play an aetiological role.

A Review of Coronary Artery Bypass Grafting in the Indigenous Australian Population.

INTRODUCTION: Indigenous Australians experience poorer health outcomes than non-Indigenous Australians. Ischaemic heart disease is a leading contributor to the mortality gap which exists between Indigenous and non-Indigenous Australians. METHODS: We reviewed the literature in regards to Indigenous Australians undergoing coronary artery bypass grafting (CABG) for management of ischaemic heart disease. RESULTS: Younger patients with higher rates of preventable risk factors constitute the Indigenous Australian CABG population. Indigenous Australian females are over-represented in series to date. High rates of left ventricular dysfunction are seen in the Indigenous CABG cohorts potentially reflecting barriers to medical care or the influence of high rates of diabetes observed in the Indigenous Australian population. The distribution of coronary artery disease appears to differ between Indigenous Australian and non-Indigenous CABG cohorts likely reflecting a difference in the referral patterns of the two population groups with diabetes again likely influencing management decisions. Reduced utilisation of arterial conduits in Indigenous Australian cohorts has been identified in a number of series. This is of particular concern given the younger age structure of the Indigenous Australian cohorts. Indigenous Australian patients suffer excess morbidity and mortality in the longer term after undergoing CABG. Ventricular dysfunction and excess comorbidities in the Indigenous Australian CABG population appear largely responsible for this. CONCLUSION: Excess morbidity and mortality endured by Indigenous Australians in the longer term following CABG appears largely contributed to by higher rates of ventricular dysfunction and comorbidities in the Indigenous Australian CABG population. Maximising internal mammary artery use and continued focus on strategies to reduce the impact of diabetes, renal impairment and heart failure in the Indigenous Australian population is essential to reduce the mortality gap experienced by Indigenous Australians secondary to ischaemic heart disease.

An Overview of Indigenous Australian Disadvantage in Terms of Ischaemic Heart Disease.

BACKGROUND: Indigenous Australians experience poorer health outcomes than non-Indigenous Australians and a significant life expectancy gap exists. Ischaemic heart disease (IHD) represents the leading specific cause of death in Indigenous Australians and is a significant, if not the most significant, contributor to the mortality gap. With this narrative review we aim to describe the burden of IHD within the Indigenous Australian community and explore the factors driving this disparity. METHODS: A broad search of the literature was undertaken utilising an electronic search of the PubMed database along with national agency databases-the Australian Institute of Health and Welfare (AIHW) and the Australian Bureau of Statistics (ABS). RESULTS: A complex interplay between multiple factors contributes to the excess burden of IHD in the Indigenous Australian population: CONCLUSIONS: In terms of IHD, Indigenous Australians experience disadvantage at multiple stages of the disease process. Ongoing efforts are needed to continue to inform clinicians of both this disadvantage and strategies to assist negating it. Further research is needed to develop evidence based practices which may help reduce this disparity in outcomes.

The burden and implications of preoperative atrial fibrillation in Australian heart valve surgery patients.

BACKGROUND: Atrial fibrillation (AF) is the most common preoperative arrhythmia in heart valve surgery patients and its prevalence is rising. This study aims to investigate the impact of AF on valve surgery early complications and survival and on valve disease of different aetiologies and populations with particular reference to Indigenous Australians with rheumatic heart disease (RHD). METHODS: The Australian and New Zealand Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database was analysed to determine the association between preoperative AF and valve surgery outcome. Its association with demographics, co-morbidities, preoperative status and short and long term outcome was assessed. RESULTS: Outcome of 1594 RHD and 19,029 non-RHD-related surgical procedures was analysed. Patients with preoperative AF were more likely to be older, female, Indigenous, to have RHD and to bear a greater burden of comorbidities. Patients with RHD and preoperative AF had a longer hospital stay and were more likely to require reoperation. Adjusted short (OR 1.4, 95% CI 1.2-1.7) and long term (HR 1.5, 95% CI 1.3-1.7) survival was inferior for patients with non-RHD preoperative AF but was no different for Indigenous and non-Indigenous Australians with RHD. CONCLUSIONS: In this prospective Australian study, patients with valve disease and preoperative AF had inferior short and long term survival. This was particularly the case for patients with non-RHD valve disease. Earlier intervention or more aggressive AF management should be investigated as mechanisms for enhancing postoperative outcomes. This may influence treatment choice and the need for ongoing anticoagulation.

Outcomes after mitral valve surgery for rheumatic heart disease.

OBJECTIVE: To further the understanding of the factors influencing outcome following rheumatic heart disease (RHD) related mitral valve surgery, which globally remains an important cause of heart disease and a particular problem in Indigenous Australians. METHODS: The Australian Cardiac Surgery Database was utilised to assess outcomes following mitral valve repair and replacement for RHD and non-RHD valve disease. The association with aetiology, demographics, comorbidities, preoperative status and operative procedure was evaluated. RESULTS: Mitral valve repairs and replacements undertaken in Australia were analysed from 119 and 1078 RHD surgical procedures and 3279 and 2400 non-RHD procedures, respectively. RHD mitral valve repair, compared with replacement, resulted in a slightly shorter hospital stay and more reoperation for valve dysfunction, but no difference in 30-day survival. In unadjusted survival analysis to 5 years, RHD mitral valve repair and replacement were no different (HR 0.86, 95% CI 0.4 to 1.7), non-RHD repair was superior to replacement (HR 1.7, 95% CI 1.4 to 2.0), RHD and non-RHD repair were no different (HR 0.9, 95% CI 0.5 to 1.7), and RHD replacement was superior to non-RHD (HR 1.5, 95% CI 1.2 to 1.9). None of these differences persisted in adjusted analyses and there was no difference in long-term survival for Indigenous Australians. CONCLUSION: In this large prospective cohort study we have demonstrated that adjusted long-term survival following RHD mitral valve repair surgery in Australia is no different to replacement and no different to non-RHD. Interpretation of valve surgery outcome requires careful consideration of patient factors that may also influence survival.

Case load and valve surgery outcome in Australia.

BACKGROUND: In Australia it has been suggested that heart valve surgery, particularly for rheumatic heart disease (RHD), should be consolidated in higher volume centres. International studies of cardiac surgery suggest large volume centres have superior outcomes. However the effect of site and surgeon case load on longer term outcomes for valve surgery has not been investigated. METHODS: The Australian and New Zealand Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database was analysed. The adjusted association between both average annual site and surgeon case load on short term complications and short and long-term survival was determined. RESULTS: Outcomes associated with 20,116 valve procedures at 25 surgical sites and by 93 surgeons were analysed. Overall adjusted analysis showed increasing site and surgeon case load was associated with longer ventilation, less reoperation and more anticoagulant complications. Increasing surgeon case load was also associated with less acute kidney injury. Adjusted 30-day mortality was not associated with site or surgeon case load. There was no consistent relationship between increasing site case load and long term survival. The association between surgeon case load and outcome demonstrated poorer adjusted survival in the highest volume surgeon group. CONCLUSIONS: In this Australian study, the adjusted association between surgeon and site case load was not simple or consistent. Overall larger volume sites or surgeons did not have superior outcomes. Mandating a particular site case load level for valve surgery or a minimum number of procedures for individual surgeons, in an Australian context, cannot be supported by these findings.

A review of outcome following valve surgery for rheumatic heart disease in Australia.

BACKGROUND: Globally, rheumatic heart disease (RHD) remains an important cause of heart disease. In Australia it particularly affects younger Indigenous and older non-Indigenous Australians. Despite its impact there is limited understanding of the factors influencing outcome following surgery for RHD. METHODS: The Australian and New Zealand Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database was analysed to assess outcomes following surgical procedures for RHD and non-RHD valvular disease. The association with demographics, co-morbidities, pre-operative status, valve(s) affected and operative procedure was evaluated. RESULTS: Outcome of 1384 RHD and 15843 non-RHD valve procedures was analysed. RHD patients had longer ventilation, experienced fewer strokes and had more readmissions to hospital and anticoagulant complications. Mortality following RHD surgery at 30 days was 3.1% (95% CI 2.2 - 4.3), 5 years 15.3% (11.7 - 19.5) and 10 years 25.0% (10.7 - 44.9). Mortality following non-RHD surgery at 30 days was 4.3% (95% CI 3.9 - 4.6), 5 years 17.6% (16.4 - 18.9) and 10 years 39.4% (33.0 - 46.1). Factors independently associated with poorer longer term survival following RHD surgery included older age (OR1.03/additional year, 95% CI 1.01 - 1.05), concomitant diabetes (OR 1.7, 95% CI 1.1 - 2.5) and chronic kidney disease (1.9, 1.2 - 2.9), longer invasive ventilation time (OR 1.7 if greater than median value, 1.1- 2.9) and prolonged stay in hospital (1.02/additional day, 1.01 - 1.03). Survival in Indigenous Australians was comparable to that seen in non-Indigenous Australians. CONCLUSION: In a large prospective cohort study we have demonstrated survival following RHD valve surgery in Australia is comparable to earlier studies. Patients with diabetes and chronic kidney disease, were at particular risk of poorer long-term survival. Unlike earlier studies we did not find pre-existing atrial fibrillation, being an Indigenous Australian or the nature of the underlying valve lesion were independent predictors of survival.

A review of valve surgery for rheumatic heart disease in Australia.

BACKGROUND: Globally, rheumatic heart disease (RHD) remains an important cause of heart disease. In Australia it particularly affects older non-Indigenous Australians and Aboriginal Australians and/or Torres Strait Islander peoples. Factors associated with the choice of treatment for advanced RHD remain variable and poorly understood. METHODS: The Australian and New Zealand Society of Cardiac and Thoracic Surgeons Cardiac Surgery Database was analysed. Demographics, co-morbidities, pre-operative status and valve(s) affected were collated and associations with management assessed. RESULTS: Surgical management of 1384 RHD and 15843 non-RHD valve procedures was analysed. RHD patients were younger, more likely to be female and Indigenous Australian, to have atrial fibrillation (AF) and previous percutaneous balloon valvuloplasty (PBV). Surgery was performed on one valve in 64.5%, two valves in 30.0% and three valves in 5.5%. Factors associated with receipt of mechanical valves in RHD were AF (OR 2.69) and previous PBV (OR 1.98) and valve surgery (OR 3.12). Predictors of valve repair included being Indigenous (OR 3.84) and having fewer valves requiring surgery (OR 0.10). Overall there was a significant increase in the use of mitral bioprosthetic valves over time. CONCLUSIONS: RHD valve surgery is more common in young, female and Indigenous patients. The use of bioprosthetic valves in RHD is increasing. Given many patients are female and younger, the choice of valve surgery and need for anticoagulation has implications for future management of RHD and related morbidity, pregnancy and lifestyle plans.

Recurrent left ventricular thrombus in Crohn's disease: a rare presentation.

A 40-year-old man with Crohn's disease was found to have recurrence of a large left ventricular mass on echocardiography during workup for stricturoplasty. He presented with left limb emboli. He had been diagnosed with a left ventricular thrombus 2 years earlier, with multiple cerebral and peripheral emboli, and underwent surgery. We carried out redo surgery, and histology revealed organized thrombus. We discuss the management of this complex case.

Cardiac surgery in Indigenous Australians--how wide is 'the gap'?

BACKGROUND: Cardiovascular disease remains the leading cause of mortality in the Indigenous Australian population. Limited research exists in regards to cardiac surgery in the Aboriginal and Torres Strait Islander (ATSI) population. We aimed to investigate risk profiles, surgical pathologies, surgical management and short term outcomes in a contemporary group of patients. METHODS: Variables were assessed for 557 consecutive patients who underwent surgery at our institution between August 2008 and March 2010. RESULTS: 19.2% (107/557) of patients were of Indigenous origin. ATSI patients were significantly younger at time of surgery (mean age 54.1±13.23 vs. 63.1±12.46; p=<0.001) with higher rates of preventable risk factors. Rheumatic heart disease (RHD) was the dominant valvular pathology observed in the Indigenous population. Significantly higher rates of left ventricular impairment and more diffuse coronary artery disease were observed in ATSI patients. A non-significant trend towards higher 30-day mortality was observed in the Indigenous population (5.6% vs. 3.1%; p=0.244). CONCLUSIONS: Cardiac surgery is generally required at a younger age in the Indigenous population with patients often presenting with more advanced disease. Despite often more advanced disease, surgical outcomes do not differ significantly from non-Indigenous patients. Continued focus on preventative strategies for coronary artery disease and RHD in the Indigenous population is required.

Migrating foreign body in mediastinum--intravascular Steinman pin.

We report a case of migration of a Steinman pin to the innominate vein. A pin was used to fix a shoulder separation but a broken piece was left unattended at the time of removal of the pin. How this piece made its way in to innominate vein is puzzling. To our knowledge migration of fixation wires to the innominate vein has not been reported previously.

Identification of isothiazole-4-carboxamidines derivatives as a novel class of allosteric MEK1 inhibitors.

The development of potent, orally bioavailable, and selective series of 5-amino-3-hydroxy-N(1-hydroxypropane-2-yl)isothiazole-4-carboxamidine inhibitors of MEK1 and MEK-2 kinase is described. Optimization of the carboxamidine and the phenoxyaniline group led to the identification of 55 which gave good potency as in vitro MEK1 inhibitors, and good oral exposure in rat.

Discovery of 3-hydroxy-4-carboxyalkylamidino-5-arylamino-isothiazoles as potent MEK1 inhibitors.

3-Hydroxy-4-carboxyalkylamidino-5-arylamino-isothiazoles were discovered as potent in vitro MEK1 inhibitors.

Late manifestation of a large congenital tracheoesophageal fistula in an adult.

Congenital tracheoesophageal fistula in an adult is a rare condition. We describe the clinical presentation in a young woman after video-assisted thoracoscopic pleurodesis for spontaneous pneumothorax. She was found to have a very wide and short fistula in her neck. The tracheoesophageal defect was closed by a trap-door flap, using the posterior wall of the trachea. The patient made an uncomplicated recovery.

Minimally invasive surgery for cardiac myxomas using an upper hemi-sternotomy and biatrial septal approach.

BACKGROUND: Minimally invasive surgery is pervading all fields of surgery with the principal benefits being: reduced pain, smaller incision, faster recovery, shorter hospital stay and reduced cost. Cardiac surgery is no different. Cardiac myxoma morbidity and mortality depends on early diagnosis, adequate exposure, complete resection, minimal manipulation and unifocal presence. We reviewed our cases of cardiac myxoma excised via an upper hemi-sternotomy with a biatrial septal cardiac approach, to demonstrate this technique as a valid alternative to a full-length median sternotomy. METHODS: From April 1997 to March 1999, one surgeon excised two cardiac myxomas via this minimal technique. Upper hemi-sternotomy was midline without transverse sternal transection. Standard aortobicaval cardiopulmonary bypass and myocardial protection were established with complete tumour excision via a biatrial septal approach commenced in the left atrial dome and extended to the right atrial appendage. RESULTS: Inpatient care was prolonged with cardiorespiratory morbidity a consequence of preoperative co-morbidities. Neither patient required return to theatre and hospital mortality was nil. Patients demonstrated reduced sternal wound pain, reduced length of incision, excellent healing and improvement in New York Heart Association functional class with no evidence of recurrence. CONCLUSIONS: Most proposed benefits of minimally invasive surgery were demonstrated in cardiac myxoma application without significant compromise to patient care and recovery using upper hemi-sternotomy and biatrial septal approach. Cardiac myxoma excision via upper hemi-sternotomy and biatrial septal approach can be achieved without compromise to patient care.