C. Raffel

The long‐term outcomes of transcoronary ablation of septal hypertrophy compared to surgical myectomy in patients with symptomatic hypertrophic obstructive cardiomyopathy

The aim of this study was to compare the long‐term outcomes of transcoronary ablation of septal hypertrophy (TASH) with open surgical myomectomy (SM) in patients with symptomatic hypertrophic obstructive cardiomyopathy (HOCM).Objectives The aim of this study was to compare the long-term outcomes of transcoronary ablation of septal hypertrophy (TASH) with open surgical myomectomy (SM) in patients with symptomatic hypertrophic obstructive cardiomyopathy (HOCM). Methods We reviewed patients who underwent either procedure at our institution. The demographics, clinical outcomes, echocardiographic parameters, and complications were compared. Results Seventy patients with HOCM were treated with either TASH (n = 47, 26 male) or SM (n = 23, 10 male). Compared to those treated with SM, patients undergoing TASH were older (57+/− 14.7 years versus 47 +/− 20.6 years, P = 0.021) and more symptomatic. A higher proportion of patients had syncope as a presenting feature in the TASH group compared to the SM group (57.5% vs. 17.4%, P = 0.002) respectively. They were also more likely to be in New York Heart Association (NYHA) class III/IV compared to the patients who underwent SM (85.1% vs. 39.1%; P < 0.001). Patients were followed for a mean period of 43 months (TASH) and 46 months (SM). Repeat procedures were more common in the TASH group (17% vs. 0%, P = 0.04) but mitral valve replacement was more common in the SM group (0% vs. 8.7%, P = 0.105). Symptom improvement, the rate of complications and all cause mortality rates were similar in both groups. Conclusions TASH compares favorably with surgical myectomy with regard to symptom resolution, rate of complications and mortality in a tertiary referral centre and should be seen as an attractive alternative to surgical myectomy in the appropriate patient population.

Transcatheter valve-in-valve replacement of degenerated bioprosthetic aortic valves: a single Australian Centre experience.

BACKGROUND Patients with degenerated surgical bioprosthetic valves may be at high risk for further surgery because of age, comorbidities and the difficulties of repeat procedures. Percutaneous valve-in-valve implantation offers what may be a simpler and safer procedure. METHODS From May 2009 to March 2014 at the Prince Charles Hospital 1625 patients underwent surgical aortic valve replacement while 262 underwent transcatheter aortic valve implantation. Twelve patients had valve-in-valve implants for degenerated bioprosthetic aortic valves. RESULTS These implants were deployed successfully without major valvular or paravalvular regurgitation. There were no periprocedural deaths, myocardial infarcts, neurological events or major vascular complications. Two patients died after 1624 and 1319days. Median survival for the remainder is 581days; they are stable with New York Heart Association class I/II functional status although 4 have a degree of patient-prosthesis mismatch, one has moderate aortic regurgitation and one required surgery for a late aortic dissection. CONCLUSION Transcatheter valve-in-valve implantation is safe and effective treatment for patients with failed bioprosthetic aortic valves for whom reoperation is considered to be hazardous.

Intracardiac echocardiography guided transeptal catheter injection of microspheres for assessment of cerebral microcirculation in experimental models.

The use of microspheres for the determination of regional microvascular blood flow (RMBF) has previously used different approaches. This study presents for the first time the intracardiac injection of microspheres using transeptal puncture under intracardiac echocardiography guidance. Five Merino sheep were instrumented and cardiovascularly supported according to local guidelines. Two catheter sheaths into the internal jugular vein facilitated the introduction of an intracardiac probe and transeptal catheter, respectively. Five million colour coded microspheres were injected into the left atrium via this catheter. After euthanasia the brain was used as proof of principle and the endpoint for determination of microcirculation at different time points. Homogeneous allocation of microspheres to different regions of the brain was found over time. Alternate slices from both hemispheres showed the following flow ranges: for slice 02; 0.57–1.02 mL/min/g, slice 04; 0.45–1.42 mL/min/g, slice 06; 0.35–1.87 mL/min/g, slice 08; 0.46–1.77 mL/min/g, slice 10; 0.34–1.28 mL/min/g. A mixed effect regression model demonstrated that the confidence interval did include zero suggesting that the apparent variability intra- and intersubject was not statistically significant, supporting the stability and reproducibility of the injection technique. This study demonstrates the feasibility of the transeptal injection of microspheres, showing a homogeneous distribution of blood flow through the brain unchanged over time and has established a new interventional model for the measurement of RMBF in ovine models.

Cerebral microcirculation during mild head injury after a contusion and acceleration experimental model in sheep

Abstract Background: Cerebral microcirculation after head injury is heterogeneous and temporally variable. Regions at risk of infarction such as peri-contusional areas are vulnerable to anaemia. However, direct quantification of the cerebral microcirculation is clinically not feasible. This study describes a novel experimental head injury model correlating cerebral microcirculation with histopathology analysis. Objective: To test the hypothesis that cerebral microcirculation at the ischaemic penumbrae is reduced over time when compared with non-injured regions. Methods: Merino sheep were instrumented using a transeptal catheter to inject coded microspheres into the left cardiac atrium, ensuring systemic distribution. After a blunt impact over the left parietal region, cytometric analyses quantified cerebral microcirculation and amyloid precursor protein staining identified axonal injury in pre-defined anatomical regions. A mixed effect regression model assessed the hourly blood flow results during 4 hours after injury. Results: Cerebral microcirculation showed temporal reductions with minimal amyloid staining except for the ipsilateral thalamus and medulla. Conclusion: The spatial heterogeneity and temporal reduction of cerebral microcirculation in ovine models occur early, even after mild head injury, independent of the intracranial pressure and the level of haemoglobin. Alternate approaches to ensure recovery of regions with reversible injury require a targeted assessment of cerebral microcirculation.

Deformation of Stabilization Arch Following Post-Dilatation of Symetis ACURATE Neo Aortic Bioprosthesis

A 78-year-old man with severe aortic stenosis and progressive exertional dyspnea (New York Heart Association functional class III) was referred for aortic valve replacement. Other comorbidities included chronic obstructive lung disease, permanent atrial fibrillation, hypertension, and bilateral

Percutaneous Transvenous Mitral Valve-in-Valve Implantation Using Commercially Available Transcatheter Valve. First Australian Experience

In patients with a degenerative mitral bioprosthesis and prohibitive surgical risk there is emerging evidence for the feasibility of valve-in-valve procedures via a percutaneous transvenous transseptal approach. This paper describes the first time this procedure has been performed in Australia.

Successful hybrid coronary artery revascularisation in a patient with severe cerebrovascular disease: a new treatment option to minimise the risk of stroke

Here we present a case involving a patient with severe distal left main coronary artery stenosis with extensive coexisting extracranial cerebrovascular disease where hybrid coronary artery revascularisation was successfully performed. This illustrates the potential for hybrid revascularisation in those patients with an inherit risk of stroke.

The Index of Microvascular Resistance (IMR) and Correlation with Traditional Cardiovascular Risk Factors in Patients with Moderate Epicardial Coronary Artery Disease

1 South Western Sydney Clinical School, The University of NSW, Sydney, NSW, Australia 2 Department of Cardiology, Liverpool Hospital, Sydney, NSW, Australia 3 Royal Brisbane Hospital, Herston, Qld, Australia 4 Cardiology Department, Auckland City Hospital, Auckland, New Zealand 5 Cardiology Department, Royal Perth Hospital, WA, Australia 6 The Dunedin School of Medicine, University of Otago, New Zealand 7 The George Institute, University of Sydney, NSW, Australia 8 Department of Cardiology, Flinders University, Bedford Park, SA, Australia 9 CardiologyDepartment,University ofWesternAustralia,WA, Australia 10 CardiacClinicalNetwork,Department ofHealth,Melbourne, Vic, Australia 11 NSW Agency for Clinical Innovation, Chatswood, NSW, Australia 12 Queensland Department of Health, QLD, Australia 13 Cardiology Department, Waikato Hospital, Hamilton, New Zealand 14 Cardiology Concord Hospital, Sydney, NSW, Australia