Changes of left ventricular mechanics after trans-catheter aortic valve implantation and surgical aortic valve replacement for severe aortic stenosis: A tissue-tracking cardiac magnetic resonance study

Background: Left ventricular (LV) mechanics are impaired in patients with severe aortic stenosis (AS). The aim of the present study was to assess their changes early and late after trans-catheter aortic valve implantation (TAVI) and surgical aortic valve replacement (AVR) using cardiac magnetic resonance (CMR) tissue-tracking imaging. Methods: In 59 patients with severe AS undergoing either TAVI (n = 35) or surgical AVR (n = 24), CMR with late gadolinium enhancement (LGE) imaging was performed before and early post-procedure to evaluate LV function and mass, and presence/extent of LGE. A third CMR scan was performed in 29 patients after a mean follow-up of 15 ± 4 months. Tissue-tracking analysis was applied to cine CMR images, to assess LV global longitudinal (GLS), circumferential (GCS) and radial (GRS) strains.
 Results: The TAVI and surgical AVR groups were similar with respect to baseline (p = 0.14) and early post-procedure (p = 0.16) LV ejection fraction. However, baseline LV GLS was significantly impaired in TAVI patients compared to surgical AVR patients (p = 0.025). Early post-procedure, TAVI resulted in a significant improvement of LV GLS (p = 0.003), while a significant worsening of LV GLS was observed early after surgical AVR (p = 0.012). At longer term follow-up, both TAVI and surgical AVR groups experienced a significant reduction of LV mass and a significant improvement of LV myocardial mechanics in all the three directions. Conclusions: Treatment-specific differences in the changes of LV myocardial mechanics early after afterload release by TAVI and surgical AVR are present. Later, both interventions are associated with an improvement of LV myocardial deformation, alongside a regression of LV hypertrophy

Surgery for rheumatic heart disease in the Northern Territory, Australia, 1997-2016: what have we gained?

Background: Between 1964 and 1996, the 10-year survival of patients having valve replacement surgery for rheumatic heart disease (RHD) in the Northern Territory, Australia, was 68%. As medical care has evolved since then, this study aimed to determine whether there has been a corresponding improvement in survival. Methods: A retrospective study of Aboriginal patients with RHD in the Northern Territory, Australia, having their first valve surgery between 1997 and 2016. Survival was examined using Kaplan-Meier and Cox regression analysis. Findings: The cohort included 281 adults and 61 children. The median (IQR) age at first surgery was 31 (18-42) years; 173/342 (51%) had a valve replacement, 113/342 (33%) had a valve repair and 56/342 (16%) had a commissurotomy. There were 93/342 (27%) deaths during a median (IQR) follow-up of 8 (4-12) years. The overall 10-year survival was 70% (95% CI: 64% to 76%). It was 62% (95% CI: 53% to 70%) in those having valve replacement. There were 204/281 (73%) adults with at least 1 preoperative comorbidity. Preoperative comorbidity was associated with earlier death, the risk of death increasing with each comorbidity (HR: 1.3 (95% CI: 1.2 to 1.5), p50 mm Hg before surgery (HR 1.9 (95% CI: 1.2 to 3.1) p=0.007) were independently associated with death. Interpretation: Survival after valve replacement for RHD in this region of Australia has not improved. Although the patients were young, many had multiple comorbidities, which influenced long-term outcomes. The increasing prevalence of complex comorbidity in the region is a barrier to achieving optimal health outcomes

Quantitative assessment of paravalvular regurgitation following transcatheter aortic valve replacement

Paravalvular aortic regurgitation (PAR) following transcatheter aortic valve implantation (TAVI) is well acknowledged. Despite improvements, echocardiographic measurement of PAR largely remains qualitative. Cardiovascular magnetic resonance (CMR) directly quantifies AR with accuracy and reproducibility. We compared CMR and transthoracic echocardiography (TTE) analysis of pre-operative and post-operative aortic regurgitation in patients undergoing both TAVI and surgical aortic valve replacement (AVR).Gareth Crouch, Phillip J Tully, Jayme Bennetts, Ajay Sinhal, Craig Bradbrook, Amy L Penhall, Carmine G De Pasquale, Robert A Baker, and Joseph B Selvanayaga

Brian Fowell Buxton (15/04/1940–20/05/2022)—Outstanding Achievements and Personal Memories

Brian F. Buxton, one of Australia's greatest cardiac surgeons, died in May 2022, aged 82 years. In June 2022, a memorial celebration of Brian's life was held in Melbourne, Australia, attended by 550 colleagues and friends from many walks of life—not only “medical people” but also friends involved in Brian's sailing and hiking activities. This Special Article includes an introduction from Professor Jayme Bennetts, President of the Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS), an abridged version of a memorial address by Professor James Tatoulis and contributions from two other long-term professional colleagues and personal friends of Buxton, Professor Jaishankar Raman and Professor Franklin Rosenfeldt, founding editor of Heart, Lung and Circulation. Buxton was an outstanding and pioneering surgeon, clinical leader, and good friend to many. The Brian F. Buxton Cardiac and Thoracic Aortic Surgery Unit in Melbourne, Australia, is now so named in honour of his outstanding achievements and as a legacy. Vale Brian F. Buxton

Early Valve Replacement for Severe Aortic Valve Disease: Effect on Mortality and Clinical Ramifications

Timing of aortic valve intervention for chronic aortic regurgitation (AR) and/or aortic stenosis (AS) potentially affects long-term survival. The 2014 American Heart Association/American College of Cardiology (AHA/ACC) guidelines provide recommendations for the timing of intervention. Subsequent to the guidelines’ release, several studies have been published that suggest a survival benefit from earlier timing of surgery for severe AR and/or AS. The aim of this review was to determine whether patients who have chronic aortic regurgitation (AR) and/or aortic stenosis (AS) have a survival benefit from earlier timing of aortic valve surgery. Medical databases were systematically searched from January 2015 to April 2020 for randomized controlled trials (RCTs) and observational studies that examined the timing of aortic valve replacement surgery for chronic AR and/or AS. For chronic AR, four observational studies and no RCTs were identified. For chronic AS, five observational studies, one RCT and one meta-analysis were identified. One observational study examining mixed aortic valve disease (MAVD) was identified. All of these studies, for AR, AS, and MAVD, found long-term survival benefit from timing of aortic valve surgery earlier than the current guidelines. Larger prospective RCTs are required to evaluate the benefit of earlier surgical intervention

Selective Serotonin Reuptake Inhibitors, Venlafaxine and Duloxetine are Associated With in Hospital Morbidity but Not Bleeding or Late Mortality After Coronary Artery Bypass Graft Surgery

Background: No Australian study has reported the association between selective-serotonin reuptake inhibitor (SSRI) and serotonin noradrenaline reuptake inhibitor (SNRI) with coronary artery bypass graft (CABG) surgery morbidity and mortality. Methods: 4136 patients underwent CABG surgery between January 1996 and December 2008 and 105 (2.5%) were SSRI/SNRI users. Bleeding events included platelet, fresh frozen plasma and packed red blood cell transfusion, reoper-ation for bleeding and gastrointestinal bleeding. In-hospital morbidity included renal failure, stroke, ventilation >24 h, deep sternal wound infection, reoperation (any cause), myocardial infarction and mortality.24 h, deep sternal wound infection, reoperation (any cause), myocardial infarction and mortality.Results: Median follow-up was 4.7 years (interquartile range, 2.3–7.9 years) and there were 727 deaths (17.6% of total). Use of SSRI/SNRI was associated with new requirement for renal dialysis (adjusted OR = 2.18; 95% CI, 1.06–4.45, p = .03) and ventilation >24 h (adjusted OR = 1.69; 95% CI, 1.03–2.78, 24 h (adjusted OR = 1.69; 95% CI, 1.03–2.78, p = .04). Neither SSRI/SNRI use nor SSRI/SNRI and con-comitant anti-platelet medication increased the odds for any bleeding events (all p > .20). No association was evident with all-cause mortality (adjusted hazard ratio = 1.60; 95% CI .59–4.35, .20). No association was evident with all-cause mortality (adjusted hazard ratio = 1.60; 95% CI .59–4.35, p = .36), or cardiac mortality (adjusted hazard ratio = .31; 95% CI, .04–2.26, p = .25). Conclusions: SSRI/SNRI users experienced an increased risk of renal dysfunction and prolonged ventilation, but not bleeding events or long-term mortality after CABG surgery

COVID-19 safety: aerosol-generating procedures and cardiothoracic surgery and anaesthesia - Australian and New Zealand consensus statement

Coronavirus disease 2019 (COVID‐19) is a contagious disease that is caused by the severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2). Health care workers are at risk of infection from aerosolisation of respiratory secretions, droplet and contact spread. There are a number of procedures that represent a high risk of aerosol generation during cardiothoracic surgery. It is important that adequate training, equipment and procedures are in place to reduce that risk. We provide a number of key recommendations, which reduce the risk of aerosol generation during cardiothoracic surgery and help protect patients and staff. These include general measures such as patient risk stratification, appropriate use of personal protective equipment, consideration to delay surgery in positive patients, and careful attention to theatre planning and preparation. There are also recommended procedural interventions during airway management, transoesophageal echocardiography, cardiopulmonary bypass, chest drain management and specific cardiothoracic surgical procedures. Controversies exist regarding the management of low risk patients undergoing procedures at high risk of aerosol generation, and recommendations for these patients will change depending on the regional prevalence, risk of community transmission and the potential for asymptomatic patients attending for these procedures. This statement reflects changes in management based on expert opinion, national guidelines and available evidence. Our knowledge with regard to COVID‐19 continues to evolve and with this, guidance may change and develop. Our colleagues are urged to follow national guidelines and institutional recommendations regarding best practices to protect their patients and themselves. Australian and New Zealand Society of Cardiac and Thoracic Surgeons and the Anaesthetic Continuing Education Cardiac Thoracic Vascular and Perfusion Special Interest Group