HeartMate 3 implantation with an emphasis on the biventricular configuration.

OBJECTIVES: Right ventricular failure following implantation of a durable left ventricular assist device (LVAD) is a major driver of mortality. Reported survival following biventricular (BiVAD) or total artificial heart (TAH) implantation remains substantially inferior to LVAD alone. We report our outcomes with LVAD and BiVAD HeartMate 3 (HM3). METHODS: Consecutive patients undergoing implantation of an HM3 LVAD between November 2014 and December 2021, at The Alfred, Australia were included in the study. Comparison was made between the BiVAD and LVAD alone groups. RESULTS: A total of 86 patients, 65 patients with LVAD alone and 21 in a BiVAD configuration underwent implantation. The median age of the LVAD and BiVAD groups was 56 years (Interquartile range 46-62) and 49 years (Interquartile range 37-55), respectively. By 4 years after implantation, 54% of LVAD patients and 43% of BiVAD patients had undergone cardiac transplantation. The incidence of stroke in the entire experience was 3.5% and pump thrombosis 5% (all in the RVAD). There were 14 deaths in the LVAD group and 1 in the BiVAD group. The actuarial survival for LVAD patients at 1 year was 85% and BiVAD patients at 1 year was 95%. CONCLUSIONS: The application of HM 3 BiVAD support in selected patients appears to offer a satisfactory solution to patients requiring biventricular support.

Use of Sutureless Valve in Aortic Root Enlargement.

AIM: The small aortic annulus is a surgical challenge in patients undergoing aortic valve replacement which may lead to patient prosthesis mismatch. Management options include aortic root enlargement, aortic root replacement, and the use of sutureless valves. In this case series, we report our results with aortic root enlargement, sutureless valve implantation, and benchtop modelling of the radial forces exerted. METHODS: Five patients underwent aortic root enlargement and insertion of the Perceval valve as part of the management strategy to enlarge their effective orifice area. We further investigate this strategy with a benchtop model to quantify the radial forces exerted by the Perceval valve on the aortic annulus. Radial and hoop forces on the aortic annulus and inner ring of the Perceval valve were recorded using a Mylar force tester. RESULTS: Five female patients with native annulus between 18mm-20mm underwent root enlargement and insertion of a Perceval S valve. The postoperative course was uncomplicated for all patients except for one who required a permanent pacemaker insertion. Transvalvular pressure gradients remained low at up to 4 years of follow-up (12 mmHg-21 mmHg), with no evidence of paravalvular leak. Benchtop testing demonstrated radial forces exerted at the annulus in all-size Perceval S valves to be within physiological variables, whereas compressive forces required to deform the valves were supraphysiological. CONCLUSIONS: The deployment of a sutureless valve within a surgical enlarged aortic root is a feasible solution in patients with a small aortic root.

Characteristics and Outcomes of a Single-Centre Cohort of Adult Congenital Heart Disease Patients Referred for Heart Transplant.

BACKGROUND: Adult congenital heart disease (ACHD) services increasingly encounter heart failure (HF) in the ageing ACHD population. Optimal timing of referral for heart transplant (HTx) evaluation in this heterogeneous population is complex and ill-defined. We aim to outline the characteristics and outcomes of ACHD patients referred for HTx from a large Australian ACHD centre. METHOD: Retrospective review of ACHD patients referred for HTx from a primary ACHD centre (1992-2021). Database analysis of patient demographics, characteristics, wait-listing, and transplantation outcomes was performed. RESULTS: A total of 45 patients (mean age 37±9.9 years old; 69% male) were referred for HTx with a mean follow-up of 5.9±6.3 years. Of these, 22 of 45 (49%) were listed and transplanted, including one heart-lung transplant. The commonest diagnosis was dextro-transposition of the great arteries (13/45, 29%). Most patients, 33 of 45 (73.3%) had undergone at least one cardiac surgery in childhood. Indications for HTx referral included HF in 34 of 45 (75%), followed by pulmonary hypertension in 7 of 45 (11%). Median transplant wait-list time was 145 days (interquartile range, 112-256). Of the 23 patients not wait-listed, the reasons included clinical stability in 13 of 45 (29%), psychosocial factors in 2 of 45 (4.4%) and prohibitive surgical risk, including multiorgan dysfunction, in 8 of 45 (17.7%). Transplant was of a single organ in most, 21 of 22 (95.5%). Overall mortality was 5 of 22 (22.7%) in those after HTx, and 14 of 23 (60.9%) in those not listed (p=0.0156). CONCLUSIONS: Increasingly, ACHD patients demonstrate the need for advanced HF treatments. HTx decision-making is complex, and increased mortality is seen in those not wait-listed. Ultimately, the referral of ACHD patients for HTx is underpinned by local decision-making and experience, wait-list times and outcomes.

2023 Cardiac Society of Australia and New Zealand Expert Position Statement on Catheter and Surgical Ablation for Atrial Fibrillation.

Catheter ablation for atrial fibrillation (AF) has increased exponentially in many developed countries, including Australia and New Zealand. This Expert Position Statement on Catheter and Surgical Ablation for Atrial Fibrillation from the Cardiac Society of Australia and New Zealand (CSANZ) recognises healthcare factors, expertise and expenditure relevant to the Australian and New Zealand healthcare environments including considerations of potential implications for First Nations Peoples. The statement is cognisant of international advice but tailored to local conditions and populations, and is intended to be used by electrophysiologists, cardiologists and general physicians across all disciplines caring for patients with AF. They are also intended to provide guidance to healthcare facilities seeking to establish or maintain catheter ablation for AF.

Extracorporeal Membrane Oxygenation for Graft Dysfunction Early After Heart Transplantation: A Systematic Review and Meta-analysis.

INTRODUCTION: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is a prevailing option for the management of severe early graft dysfunction. This systematic review and individual patient data (IPD) meta-analysis aims to evaluate (1) mortality, (2) rates of major complications, (3) prognostic factors, and (4) the effect of different VA-ECMO strategies on outcomes in adult heart transplant (HT) recipients supported with VA-ECMO. METHODS AND RESULTS: We conducted a systematic search and included studies of adults (≥18 years) who received VA-ECMO during their index hospitalization after HT and reported on mortality at any timepoint. We pooled data using random effects models. To identify prognostic factors, we analysed IPD using mixed effects logistic regression. We assessed the certainty in the evidence using the GRADE framework. We included 49 observational studies of 1477 patients who received VA-ECMO after HT, of which 15 studies provided IPD for 448 patients. There were no differences in mortality estimates between IPD and non-IPD studies. The short-term (30-day/in-hospital) mortality estimate was 33% (moderate certainty, 95% confidence interval [CI] 28%-39%) and 1-year mortality estimate 50% (moderate certainty, 95% CI 43%-57%). Recipient age (odds ratio 1.02, 95% CI 1.01-1.04) and prior sternotomy (OR 1.57, 95% CI 0.99-2.49) are associated with increased short-term mortality. There is low certainty evidence that early intraoperative cannulation and peripheral cannulation reduce the risk of short-term death. CONCLUSIONS: One-third of patients who receive VA-ECMO for early graft dysfunction do not survive 30 days or to hospital discharge, and one-half do not survive to 1 year after HT. Improving outcomes will require ongoing research focused on optimizing VA-ECMO strategies and care in the first year after HT.

Mitral Valve Regurgitation After Lung Transplantation: Aetiology, Management and Outcome.

BACKGROUND: Problematic mitral regurgitation (MR) may develop following lung transplantation (LTx). There is limited information on the management of MR in LTx patients, as such we sought to evaluate our centre's experience. METHODS: From 2000 to 2019, 1,054 patients underwent LTx at our centre (896 bilateral, 158 single). We identified patients in whom significant MR developed at any point post-LTx. The aetiology of MR, management and outcome were retrospectively analysed. RESULTS: Eight (8) patients developed severe MR post-LTx, six following bilateral LTx and two following single LTx. Lung transplantation indications included interstitial lung disease (n=5), chronic obstructive pulmonary disease (n=2) and pulmonary arterial hypertension (n=1). Severe MR occurred intraoperatively (n=1), postoperative day 1 (n=1) with the remaining six cases between 80 and 263 days post-LTx. The aetiology was noted to be due to severe left ventricular dysfunction following unmasking of a chronically pulmonary hypertension-related under-preloaded left ventricle in one case, and in the remaining seven patients causes included myxomatous degeneration, ischaemic MR, and functional MR due to annular dilatation. In the patient with intraoperative severe MR, the MR became mild with veno-arterial extracorporeal membrane oxygenation (VA-ECMO) and in the remaining seven patients a variety of procedures were used, including mitral valve repair, valve replacement and transcatheter edge-to-edge mitral valve repair. All patients survived the mitral procedure. Two (2) deaths occurred at 12.9 years (stroke) and 5 years (cancer) from mitral valve surgery. CONCLUSIONS: Development of significant mitral valve regurgitation is a rare but morbid complication after lung transplantation. This may represent the progressive natural history of pre-existing degenerative mitral valve disease and rarely, early after transplantation may be related to changes in ventricular geometry. Management of severe MR can follow the same management approach as in the non-transplant community, with the expectation of similarly good results.

Selective brain hypothermia: feasibility and safety study of a novel method in five patients.

BACKGROUND/OBJECTIVE: Reduction of brain temperature remains the most common method of neuroprotection against ischemic injury employed during cardiac surgery. However, cooling delivered via the cardiopulmonary bypass circuit is brief and cooling the body core along with the brain has been associated with a variety of unwanted effects. This study investigated the feasibility and safety of a novel selective brain cooling approach to induce rapid, brain-targeted hypothermia independent of the cardiopulmonary bypass circuit. METHODS: This first-in-human feasibility study enrolled five adults undergoing aortic valve replacement with cardiopulmonary bypass support. During surgery, the NeuroSave system circulated chilled saline within the pharynx and upper esophagus. Brain and body core temperature were continuously monitored. Adverse effects, cardiopulmonary function, and device function were noted. RESULTS: Patient 1 received cooling fluid for an insignificant period, and Patients 2-5 successfully underwent the cooling procedure using the NeuroSave system for 56-89 minutes. Cooling fluid was 12°C for Patients 1-3, 6°C for Patient 4, and 2°C for Patient 5. There were no NeuroSave-related adverse events and no alterations in cardiopulmonary function during NeuroSave use. Brain temperature decreased by 3°C within 15 minutes and remained at least 3.5°C colder than the body core. During a brief episode of hypotension in one patient, the brain cooled an additional 4°C in 2 minutes, briefly reaching 27.4°C. CONCLUSION: The NeuroSave system can induce rapid brain-targeted hypothermia and simultaneously maintain a favorable body-brain temperature gradient, even during hypotension. Further studies are required to evaluate the function of the system during longer periods of use.

Post Cardiotomy Extra Corporeal Membrane Oxygenation: Australian Cohort Review.

BACKGROUND: Over the last two decades, technological advancements in the delivery of extra corporeal membrane oxygenation (ECMO) have seen its use broaden and results improve. However, in the post cardiotomy ECMO patient group, survival remains very poor without significant improvements over the last two decades. Our study aims to report on the Australian experience, with the intention of providing background data for the formation of guidelines in the future. METHODS: Retrospective analysis of prospectively collected data from the Australian and New Zealand Society of Cardiothoracic Surgeons (ANZSCTS) Database was performed. The ANZSCTS database captures at least 60% of cardiac surgical data in Australia, annually. Data was collected on adult patients who received ECMO post cardiotomy from September 2016 to November 2017 inclusive. Transplant and primary cardiomyopathy patients were excluded. RESULTS: Of the 16,605 adult patients undergoing cardiac surgery in the 15-month period of the study, 87 patients required post cardiotomy ECMO (0.52%). The average age of the entire cohort was 56 years. Overall survival to discharge was 43.7% (n=38). Multivariable logistic regression analysis demonstrated that multiorgan failure (MOF), increasing age and longer cardiopulmonary bypass time were significant predictors of in hospital mortality. CONCLUSIONS: Post cardiotomy ECMO support is an uncommon condition. Survival in this study appears to be better than historical reports. Identification of poor prognostic indicators in this study may help inform the development of guidelines for the most appropriate use of this support modality.

A real-life experience with HeartMate III.

BACKGROUND: The HeartMate III (HM3) left ventricular assist device (LVAD) is the most recent LVAD to receive CE Mark and the Food and Drug Administration approval. It is a fully magnetically levitated pump with no reported haemolysis, pump thrombosis or pump failure in the first in-man study (a previous stody). It has now received market approval in the European Union, United States of America, and Australia. We reviewed our real-life experience with the device, to assess outcomes over the medium term. METHODS: We conducted a retrospective review of prospectively collected data for 33 consecutive patients implanted with a HM3 LVAD between November 2014 and October 2018 at The Alfred Hospital, Melbourne, Australia. RESULTS: Of the 33 patients, 31 remained alive at the census date, with only two early deaths and 11 patients transplanted. There were no pump thromboses, but there were three cases of clot ingestion (two on the right and one on the left). Seven patients required permanent biventricular assist device support. The duration of HM3 support at the time of census was a median of 196 (interquartile range, 118-386) days. CONCLUSION: This series demonstrates excellent results of the HM3 LVAD in an uncensored, real-life, consecutive group of patients in a single institution.

Donor Lung Procurement by Surgical Fellow With an Expectation of High Rate of Lung Utilisation.

There is an ever increasing demand for donor lungs in patients waiting for transplantation. Lungs of many potential donors will be rejected if the standard criteria for donor assessment are followed. We have expanded our donor lung pool by accepting marginal donors and establishing a donation after circulatory death program. We have achieved comparable results using marginal donors and accepting donor lungs following donation after circulatory death. We present our assessment and technical guidelines on lung procurement taking into consideration an increasingly complex cohort of lung donors. These guidelines form the basis of the lung procurement training program involving surgical Fellows at the Alfred Hospital in Melbourne, Australia.

Cost comparison of heart transplant vs. left ventricular assist device therapy at one year.

With the worldwide shortage of donor organs, use of ventricular assist device (VAD) therapy is rapidly increasing in both the bridge to transplant and destination therapy settings. However, the high cost of VADs and VAD care is a cause for concern for policy makers who have relied on the limited supply of donor hearts to naturally cap health expenditure on heart transplantation (HTx). We sought to compare costs of the first 12 months of care of VADs vs. HTx. Single center retrospective study utilizing real generated costs over a three yr span from 2010-2012. Only patients with 12 months of costing data were included. Costs of 28 HTx patients and 24 VAD patients were analyzed. Index admission costs were more than double in the VAD group compared to the HTx group and this was driven by the procurement costs and length of stay which increased almost all aspects of in hospital care costs. Subsequent costs were six times higher in the HTx group and this was driven largely by pharmaceuticals. VAD therapy remains a very expensive treatment option for end stage heart failure patients. Device prices need to reduce substantially to make this a more widely applicable and cost effective treatment option.

Extracorporeal Life Support Bridge to Ventricular Assist Device: The Double Bridge Strategy.

In patients requiring left ventricular assist device (LVAD) support, it can be difficult to ascertain suitability for long-term mechanical support with LVAD and eventual transplantation. LVAD implantation in a shocked patient is associated with increased morbidity and mortality. Interest is growing in the utilization of extracorporeal life support (ECLS) as a bridge-to-bridge support for these critically unwell patients. Here, we reviewed our experience with ECLS double bridging. We hypothesized that ECLS double bridging would stabilize end-organ dysfunction and reduce ventricular assist device (VAD) implant perioperative mortality. We conducted a retrospective review of prospectively collected data for 58 consecutive patients implanted with a continuous-flow LVAD between January 2010 and December 2013 at The Alfred Hospital, Melbourne, Victoria, Australia. Twenty-three patients required ECLS support pre-LVAD while 35 patients underwent LVAD implantation without an ECLS bridge. Preoperative morbidity in the ECLS bridge group was reflected by increased postoperative intensive care duration, blood loss, blood product use, and postoperative renal failure, but without negative impact upon survival when compared with the no ECLS group. ECLS stabilization improved end-organ function pre-VAD implant with significant improvements in hepatic and renal dysfunction. This series demonstrates that the use of ECLS bridge to VAD stabilizes end-organ dysfunction and reduces VAD implant perioperative mortality from that traditionally reported in these "crash and burn" patients.

Right ventricular failure after implantation of continuous flow left ventricular assist device: analysis of predictors and outcomes.

Postoperative right ventricular failure is a serious complication for up to 50% of patients following LVAD insertion. Predicting RV failure is an important factor for patients as planned BiVAD support has been shown to correlate with better outcomes compared to delayed BiVAD to LVAD conversion. This retrospective study examined prospectively collected data for 101 patients implanted with an LVAD between 2003 and 2013, aiming to establish preoperative predictive factors for RVF post-LVAD insertion, analyze outcomes, and validate existing RVF scoring systems. In our cohort, 63 patients (62.4%) developed RV failure and consequently demonstrated consistently poorer survival throughout the follow-up period (log-rank p = 0.01). Multivariable logistic regression identified two significant variables: cardiac index <2.2 preoperatively despite inotropic support (OR 4.6 [95%CI 1.8-11.8]; p = 0.001) and preoperative tricuspid regurgitation (OR 8.1 [95%CI 1.9-34]; p = 0.004). Patients who developed RV failure had more complicated postoperative courses including longer ICU stay (p < 0.001), higher incidence of transfusions (p = 0.03) and re-intubation (p = 0.001), longer ventilation duration (p < 0.001), and higher incidence of returning to theater (p = 0.0008). This study found that previous validation models had only moderate correlation with our population emphasizing the need for prospective validation of these scores in the current era of continuous flow devices.

Is a Bioprosthetic Valve in the Aortic Position Desirable with a Continuous Flow LVAD?

Commissural fusion of the native aortic valve in a patient with a continuous flow left ventricular assist device (LVAD) is a known phenomenon. This may result in aortic insufficiency (AI) leading to symptomatic heart failure. In patients with AI at the time of LVAD implantation, repairing, or replacing the aortic valve is advisable. We describe a patient who had a severe dilated cardiomyopathy and moderate AI who underwent implantation of an LVAD and aortic valve replacement with a bioprosthesis that subsequently developed commissural fusion which was found at the time of heart transplantation. This case highlights the conundrum of the management of AI in patients requiring LVAD support.

Procurement of lungs for transplantation following donation after circulatory death: the Alfred technique.

INTRODUCTION: Donation after circulatory death (DCD) is an evolving method for lung transplantation (LTx) with results comparable to donation after brain death (DBD). MATERIALS AND METHODS: DCD lung transplant program requires a systematic approach for an efficient utilization of hospital resources. The surgical techniques have been developed to minimize the ischemic time during lung procurement. We have presented our management protocol and the surgical techniques as used at the Alfred Hospital in Melbourne, Australia. RESULTS: We have transplanted 92 recipients with lungs procured from 91 donors over an 8 year period from May 2006 to July 2014. This accounted for an extra 19% lung transplant operations performed during this time period. Operative mortality was 1% and 8 year survival was 71% in DCD lung recipients. CONCLUSIONS: DCD lung transplantation provides an additional significant pool of lung donors with satisfactory short and long term outcomes.

Mechanical circulatory assist as a bridge to heart retransplantation in adolescents.

We report our experience with an adolescent patient who required complex management leading to retransplantation for coronary allograft vasculopathy and also review the role of ventricular assist device support in patients with this clinical entity.

Long-term right ventricular support with a centrifugal ventricular assist device placed in the right atrium.

This case series outlines the technique and results of right ventricular assist device (RVAD) support with the off-label use of the centrifugal HeartWare HVAD (HeartWare Inc., Framingham, MA, USA) for long-term support. Four patients in our institution have been implanted with BiVADs, using the Heartware device as the RVAD, and supported for between 117 days and 772 days. Three of the patients have been successfully supported for over 18 months. Three patients have successfully been transplanted and one patient remains on the device, now approaching two years of support. None of the patients have had RVAD device-related complications.

Surgical stabilisation of rib fractures: A meta-analysis of randomised controlled trials.

INTRODUCTION: Rib fixation for ventilator dependent flail chest patients has become a mainstay of management in major trauma centres. However, the expansion of rib fixation for fractured ribs beyond this remains largely in the hands of enthusiasts with the benefits in non ventilator dependent groups largely unproven. Previous meta-analyses have largely included non-randomised and retrospective data, much of which is now more than two decades out of date. We wanted to perform an updated meta-analysis including only rigorous prospective trials which were randomised. Further we wanted to include quality of life outcomes which have not been previously examined in published meta-analyses. METHODS: This meta-analysis was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines and included randomised controlled trials only, of rib fixation compared to non-operative management in adult patients. RESULTS: Eight studies comprising 752 patients of whom 372 had been randomised to receive rib fixation were included. Benefits of rib fixation were identified with significant reductions in mechanical ventilation and lengths of stay (both ICU and hospital) as well as rates of pneumonia and tracheostomy. No significant benefit in quality of life at 6 months was identified. CONCLUSION: Operative intervention for rib fractures leads to significantly lower rates of pneumonia, lengths of intensive care stay and time on mechanical ventilation compared to non-operative intervention. Further study is needed to investigate quality of life improvements after rib fractures as operative rib fixation expands to non-ventilator dependent groups.

Impact of postoperative hyperlactatemia in orthotopic heart transplantation.

BACKGROUND: Hyperlactatemia (HL) is a common phenomenon after cardiac surgery which is related to tissue hypoperfusion and hypoxia and associated with poor outcomes. It is also often seen in the postoperative period after orthotopic heart transplantation (OHTx), but the association between HL and outcomes after OHTx is not well known. We evaluated the incidence and outcome of HL after OHTx. METHODS: This was a retrospective study of 209 patients who underwent OHTx between January 2011 and December 2020. Patients were classified into 3 groups according to their peak lactate levels within the first 72 h postoperatively: group 1, normal to mild hyperlactatemia (<5 mmol/L, n = 42); group 2, moderate hyperlactatemia (5-10 mmol/L, n = 110); and group 3, severe hyperlactatemia (>10 mmol/L, n = 57). The primary composite endpoint was all-cause mortality or postoperative initiation of veno-arterial extracorporeal membrane oxygenation (VA ECMO) within 30 days. Secondary endpoints included duration of mechanical ventilation, intensive care unit length of stay, and hospital length of stay. RESULTS: Patients with higher postoperative peak lactate levels were more commonly transplanted from left ventricular assist device support (33.3 % vs 50.9 % vs 64.9, p < 0.01) and had longer cardiopulmonary bypass time [127 min (109-148) vs 141 min (116-186) vs 153 min (127-182), p = 0.02]. Composite primary endpoint was met in 18 patients (8.6 %) and was significantly more common in patients with higher postoperative peak lactate levels (0.0 % vs 6.4 % vs 19.3 %, p < 0.01). CONCLUSIONS: Severe hyperlactatemia following orthotopic heart transplant was associated with an increased risk of post-transplant VA ECMO initiation and mortality at 30 days.

Hypothermic oxygenated perfusion (HOPE) safely and effectively extends acceptable donor heart preservation times: Results of the Australian and New Zealand trial.

BACKGROUND: Cold static storage preservation of donor hearts for periods longer than 4 hours increases the risk of primary graft dysfunction (PGD). The aim of the study was to determine if hypothermic oxygenated perfusion (HOPE) could safely prolong the preservation time of donor hearts. METHODS: We conducted a nonrandomized, single arm, multicenter investigation of the effect of HOPE using the XVIVO Heart Preservation System on donor hearts with a projected preservation time of 6 to 8 hours on 30-day recipient survival and allograft function post-transplant. Each center completed 1 or 2 short preservation time followed by long preservation time cases. PGD was classified as occurring in the first 24 hours after transplantation or secondary graft dysfunction (SGD) occurring at any time with a clearly defined cause. Trial survival was compared with a comparator group based on data from the International Society of Heart and Lung Transplantation (ISHLT) Registry. RESULTS: We performed heart transplants using 7 short and 29 long preservation time donor hearts placed on the HOPE system. The mean preservation time for the long preservation time cases was 414 minutes, the longest being 8 hours and 47 minutes. There was 100% survival at 30 days. One long preservation time recipient developed PGD, and 1 developed SGD. One short preservation time patient developed SGD. Thirty day survival was superior to the ISHLT comparator group despite substantially longer preservation times in the trial patients. CONCLUSIONS: HOPE provides effective preservation out to preservation times of nearly 9 hours allowing retrieval from remote geographic locations.