"Between a rock and the mitral valve space": Transcatheter mitral valve-in-valve implantation for paravalvular leak and refractory hemolysis complicated by circumflex coronary occlusion.

Transcatheter mitral valve implantation (TMVI) is an emerging field in structural cardiology. A particularly difficult group to treat is high-risk patients requiring valve in mitral annular calcification (ViMAC) intervention, with overall poor procedural success and outcomes in recent registries. This case highlights an unusual complication of paravalvular regurgitation (PVL) through the uncovered stent frame of a balloon expandable transcatheter heart valve (THV) on the left ventricular side of the prosthesis, leading to mechanical hemolysis and subsequent anuric renal failure post a ViMAC procedure. Attempts to treat the PVL with an occlusion plug device were unsuccessful and led to left circumflex coronary occlusion secondary to mechanical compression of the vessel in the posterior mitral valve annulus, a previously unreported phenomenon. A repeat valve-in-valve procedure was performed to treat the PVL, and immediate angioplasty resolved the left circumflex occlusion. High-risk patients requiring TMVI pose multiple challenges to Heart Teams in the treatment of valve pathology. Optimal procedural planning, multimodality imaging, improved THVs, and the awareness of potential complications are fundamental in overcoming the learning curve of TMVI and improved outcome for patients requiring ViMAC.

Contemporary review of severe aortic stenosis.

Severe aortic stenosis (AS) is the most common form of valvular heart disease in the developed world, with a rising prevalence due to an ageing Australian population. Transcatheter aortic valve implantation (TAVI) offers a less invasive option for the treatment of severe AS, with evidence supporting TAVI compared with medical therapy in inoperable patients and superior with surgical aortic valve replacement (SAVR) in high-risk patients. Equal outcomes have been observed in all-comer intermediate-risk populations. The Heart Team utilises a shared decision-making approach between physicians and surgeons in risk-stratifying patients and reduces the intrinsic bias that may occur if decisions are made in isolation. Geriatric assessment is useful for identifying preoperative frailty, a major risk factor for death post-aortic valve intervention. In severe AS, a decision can be made collaboratively to pursue TAVI, SAVR, a Ross Procedure or conservative management. The learning curve associated with TAVI has improved markedly, with overall complication rates decreasing around the world. Contemporary changes in practice, such as conscious sedation without general anaesthesia, expedited recovery and early discharge, will likely improve cost-effectiveness. In 2018, TAVI is a well-established procedure in Australia that has revolutionised the management of severe AS. In the future, with an expanding elderly population, the number of patients to benefit from transcatheter therapies for severe AS is hypothesised to increase 4-10-fold. Heart Team assessment is crucial in patients with severe AS to direct appropriate management.

Transcatheter aortic valve implantation for severe aortic stenosis in the Australian regional population.

OBJECTIVE: To compare clinical and functional outcomes of regional and urban patients after transcatheter aortic valve implantation for severe aortic stenosis. METHODS: Data were collected at patient follow-up post-transcatheter aortic valve implantation at 30 days and 12 months. Patients were stratified by residential postcodes into remoteness areas using the Australian Statistical Geography Standard. DESIGN: Retrospective cohort study. SETTING: Single-centre tertiary referral hospital. PARTICIPANTS: Patients undergoing transcatheter aortic valve implantation (n = 142) from 2009 to 2018 were analysed, with 77 patients (54.2%) residing in regional Victoria and New South Wales. MAIN OUTCOME MEASURES: Procedural success, adverse event rates, readmission rates, mortality rates, loss to follow-up and functional improvement. RESULTS: Patients residing in regional areas had a lower mean age (81.8 vs 83.7 years) and proportion of Stage 4 or 5 chronic kidney disease (1.3% vs 9.2%), compared with urban patients. Procedural characteristics and immediate post-procedural outcomes were similar between both groups. There was no statistically significant difference in mortality, readmission rates or loss to follow-up between the two cohorts. Regional patients demonstrated poorer rates of functional improvement at 30 days (50.7% vs 67.7%); however, this difference was not sustained at 12 months (79.2% vs 71.0%). Frailty was demonstrated to be an independent predictor of poor 30-day functional improvement. CONCLUSION: Regional patients treated with transcatheter aortic valve implantation for severe aortic stenosis have non-inferior 30-day and 12-month outcomes, when compared with urban patients. Frailty is a predictor of poor functional improvement post-transcatheter aortic valve implantation.

Anatomy of a Transcatheter Mitral Valve Service.

Transcatheter mitral therapies offer treatment options to selected patients who are unable to undergo open procedures due to prohibitive surgical risk. Data detailing the design and structure of transcatheter mitral services to ensure appropriate patient selection and tailored management strategies is lacking. We report our initial experience of developing and running a purpose-built transcatheter mitral service. The nature and number of referral sources, the multi-disciplinary make-up of the dedicated Mitral Heart Team and the use of integrative imaging assessment with incorporation of computational solutions are discussed. In addition, a summary of the clinical decision-making process is presented. This report sets out a framework from which future clinics can evolve to improve and streamline the delivery of transcatheter mitral therapies.