Durable ventricular assist devices for patients with advanced heart failure: the New Zealand experience.

Aims: The prevalence of heart failure in New Zealand is increasing. A small number of select patients with predicted poor short-term survival are candidates for advanced heart failure therapies such as transplantation and durable mechanical circulatory support (MCS). The aim of our study was to introduce left ventricular assist devices (LVADs) to the wider clinicians and highlight their role in managing patients with advanced heart failure in New Zealand.

Correcting bias in cardiac geometries derived from multimodal images using spatiotemporal mapping.

Cardiovascular imaging studies provide a multitude of structural and functional data to better understand disease mechanisms. While pooling data across studies enables more powerful and broader applications, performing quantitative comparisons across datasets with varying acquisition or analysis methods is problematic due to inherent measurement biases specific to each protocol. We show how dynamic time warping and partial least squares regression can be applied to effectively map between left ventricular geometries derived from different imaging modalities and analysis protocols to account for such differences.

Impaired calcium handling mechanisms in atrial trabeculae of diabetic patients.

The aim of this study was to investigate cardiomyocyte Ca handling and contractile function in freshly excised human atrial tissue from diabetic and non-diabetic patients undergoing routine surgery. Multicellular trabeculae (283 ± 20 μm in diameter) were dissected from the endocardial surface of freshly obtained right atrial appendage samples from consenting surgical patients. Trabeculae were mounted in a force transducer at optimal length, electrically stimulated to contract, and loaded with fura-2/AM for intracellular Ca measurements.

MITEA: A dataset for machine learning segmentation of the left ventricle in 3D echocardiography using subject-specific labels from cardiac magnetic resonance imaging.

Segmentation of the left ventricle (LV) in echocardiography is an important task for the quantification of volume and mass in heart disease. Continuing advances in echocardiography have extended imaging capabilities into the 3D domain, subsequently overcoming the geometric assumptions associated with conventional 2D acquisitions. Nevertheless, the analysis of 3D echocardiography (3DE) poses several challenges associated with limited spatial resolution, poor contrast-to-noise ratio, complex noise characteristics, and image anisotropy.

Comparison of percutaneous MitraClip versus mitral valve surgery for severe mitral regurgitation: a meta-analysis: Mitraclip and mitral valve surgery meta-analysis.

Aims: Mitral valve surgery (MVS) is the gold-standard treatment for severe symptomatic mitral regurgitation. Percutaneous mitral valve interventions such as the MitraClip procedure offer another dimension to its management particularly in high-risk patients. We meta-analysed the outcomes of MitraClip and MVS.

Nanoscale Organisation of Ryanodine Receptors and Junctophilin-2 in the Failing Human Heart.

The disrupted organisation of the ryanodine receptors (RyR) and junctophilin (JPH) is thought to underpin the transverse tubule (t-tubule) remodelling in a failing heart. Here, we assessed the nanoscale organisation of these two key proteins in the failing human heart. Recently, an advanced feature of the t-tubule remodelling identified large flattened t-tubules called t-sheets, that were several microns wide.

Systematic Comparison of Left Ventricular Geometry Between 3D-Echocardiography and Cardiac Magnetic Resonance Imaging.

Left ventricular (LV) volumes estimated using three-dimensional echocardiography (3D-echo) have been reported to be smaller than those measured using cardiac magnetic resonance (CMR) imaging, but the underlying causes are not well-understood. We investigated differences in regional LV anatomy derived from these modalities and related subsequent findings to image characteristics. Seventy participants (18 patients and 52 healthy participants) were imaged with 3D-echo and CMR (<1 h apart).

Loss of troponin-T labelling in endomyocardial biopsies of cardiac transplant patients is associated with increased rejection grading.

Acute cellular rejection after cardiac transplantation surgery is routinely monitored by pathological assessment of haematoxylin and eosin (H&E) histology of endomyocardial biopsies (EMB). Unfortunately, there is considerable variation in the diagnosis of rejection that has been attributed to the subjectivity involved in assessing the degree of (a) inflammatory infiltrate and (b) myocyte damage. In this work, we sought to investigate the potential of high contrast confocal microscopy for numerically assessing inflammatory infiltrate and myocyte damage in EMB histology.

Large Left Ventricular Outflow Tract Pseudoaneurysm Closed Percutaneously From a Novel Apical Approach.

An incidental finding of a large left ventricular outflow tract pseudoaneurysm in a 74-year-old man, with high surgical risk, was managed with a novel, fully percutaneous, left ventricular apical approach. The pseudoaneurysm defect and the apical puncture site were successfully closed with Amplatzer septal occluders with successful positioning, as demonstrated on cardiac computed tomography at 6 weeks follow-up. ().

Outcomes of patients with ST elevation myocardial infarction in the era of second-generation drug eluting stents; five-year follow-up.

Aim: The second-generation everolimus and zotarolimus drug eluting stents (DES) have shown superiority for repeat revascularisation and safety to the first-generation devices for stable patients. However, the benefit of those devices in the setting of ST elevation myocardial infarction (STEMI) has remained questionable due to concern regarding stent thrombosis (ST) seen with the first-generation devices. We review the outcomes of patients with STEMI treated in our centre at a time when the second-generation DES became the standard of care.

Socio-Economic Disparity is Not Linked to Outcome Following Heart Transplantation in New Zealand.

Background: Socio-economic deprivation (SED) is emerging as a risk factor for acute graft rejection (AR) and reduced survival of heart transplant (HT) recipients. The study aim was to evaluate any association between SED status of HT recipients and the development of early AR and long-term survival in New Zealand.

Methods: This was a retrospective cohort study.

Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary "Heart Team" According to Treatment Allocation.

Background: Transcatheter aortic valve implantation (TAVI) is an alternative and effective contemporary intervention to surgical aortic valve replacement (SAVR) for patients with severe aortic valve disease at increased surgical risk. Guidelines recommend a multidisciplinary "Heart Team" (MHT) review of patients considered for a TAVI procedure, but this has been little studied. We reviewed the characteristics, treatments and outcomes of such patients reviewed by the MHT at our centre.

Natural history of a systemic right ventricle.

The natural history of a systemic right ventricle after an atrial switch procedure has yet to be fully characterised. We describe the case of the longest surviving patient at our institution who underwent a Mustard Baffle correction for dextro-transposition of great arteries in childhood. Over following decades he was reviewed regularly with deteriorating systemic right ventricle function.

Patent Foramen Ovale Closure Versus Medical Therapy for Cryptogenic Stroke: Meta-Analysis of Randomised Trials.

Background: Patent foramen ovale (PFO) is a common anatomic variant associated with cryptogenic stroke. Percutaneous PFO closure in these patients to prevent recurrent neurological events has been controversial for decades, and mixed results have been reported from past and recent observational and randomised studies. This meta-analysis of randomised trials aims to compare the efficacy and safety of PFO closure with medical therapy for cryptogenic stroke patients.

Highly variable contractile performance correlates with myocyte content in trabeculae from failing human hearts.

Heart failure (HF) is defined by compromised contractile function and is associated with changes in excitation-contraction (EC) coupling and cardiomyocyte organisation. Tissue level changes often include fibrosis, while changes within cardiomyocytes often affect structures critical to EC coupling, including the ryanodine receptor (RyR), the associated protein junctophilin-2 (JPH2) and the transverse tubular system architecture. Using a novel approach, we aimed to directly correlate the influence of structural alterations with force development in ventricular trabeculae from failing human hearts.

Long and short of optimal stent design.

The ideal stent must fulfil a broad range of technical requirements. Stents must be securely crimped onto the delivery balloon and, in this form, must have a low profile and be sufficiently flexible to facilitate deliverability to the lesion site without distortion or displacement. Following expansion, stents must exert sufficient radial force on the vessel wall to overcome lesion resistance and elastic recoil.

Increased collagen within the transverse tubules in human heart failure.

Aims: In heart failure transverse-tubule (t-tubule) remodelling disrupts calcium release, and contraction. T-tubules in human failing hearts exhibit increased labelling by wheat germ agglutinin (WGA), a lectin that binds to the dystrophin-associated glycoprotein complex. We hypothesized changes in this complex may explain the increased WGA labelling and contribute to t-tubule remodelling in the failing human heart.