S. Kyranis

Outcomes Following Melody Transcatheter Pulmonary Valve Implantation for Right Ventricular Outflow Tract Dysfunction in Repaired Congenital Heart Disease: First Reported Australian Single Centre Experience

BACKGROUND Transcatheter pulmonary valve implantation (TPVI) with the Melody® transcatheter pulmonary valve (TPV) has demonstrated good haemodynamic and clinical outcomes in the treatment of right ventricular outflow tract (RVOT) conduit dysfunction in patients with repaired congenital heart disease CHD. We present the first Australian single centre experience of patients treated with Melody TPV. METHOD A prospective, observational registry was developed to monitor clinical and haemodynamic outcomes in patients with RVOT dysfunction treated with the Melody TPV (Medtronic Inc, Minneapolis, United States). RESULTS Seventeen patients underwent TPVI with Melody TPV at The Prince Charles Hospital between January 2009 and February 2016 with a median (range) age of 34 (R: 15-60). Fifteen (88%) were NYHA Class 2 dyspnoea and 11 (59%) had corrected Tetralogy of Fallot. Indication for TPVI was stenosis in eight (47%), regurgitation in two (12%) and mixed dysfunction in seven (41%). Device implantation was successful in all patients. Peak RVOT gradient was significantly reduced and there was no significant regurgitation post procedure. There was one (6%) major procedural adverse event and two (12%) major adverse events at last recorded follow-up. There were no patient deaths. Follow-up cardiac magnetic resonance imaging revealed a significant reduction in indexed right ventricular end diastolic volume. CONCLUSION This study confirms the safety and effectiveness of TPVI with Melody TPV for RVOT dysfunction in repaired CHD.

Predictors of significant coronary artery disease in atrial fibrillation: are cardiac troponins a useful measure

BACKGROUND Cardiac Troponin I (cTnI) is frequently measured in patients presenting with symptomatic atrial fibrillation (AF). The significance of elevated cTnI levels in this patient cohort is unclear. We investigated the value of cTnI elevation in this setting and whether it is predictive for significant coronary artery disease (sCAD). METHODS We conducted a retrospective, single-center, case-control study of 231 patients who presented with symptomatic AF to The Prince Charles Hospital emergency department, Brisbane, Australia between 2006 and 2014. Patients who underwent serial cTnI testing and assessment for CAD were included. Clinical variables that are known to predict CAD and could potentially predict cTnI elevation were collected. Binary logistic regression was performed to identify predictors of sCAD and cTnI elevation. RESULTS Cardiac Troponin I elevation above standard cut off was not predictive for sCAD after adjustment for other predictors (OR 1.62, 95% CI 0.79-3.32. p=0.19). However, the highest cTnI concentration value (cTnI peak) was predictive for sCAD (OR 2.02, 95% CI 1.02-3.97, p=0.04). Dyspnea on presentation (OR 4.52, 95% CI 1.87-10.91, p=0.001), known coronary artery disease (OR 3.44, 95% CI 1.42-8.32, p=0.006), and ST depression on the initial electrocardiogram (OR 2.57, 95% CI 1.11-5.97, p=0.028) predicted sCAD in our cohort, while heart rate on initial presentation was inversely correlated with sCAD (OR 0.99, 95% CI 0.971-1.00, p=0.034). CONCLUSION Troponin elevation is common in patients presenting to hospital with acute symptomatic AF and it is not a reliable indicator for underlying sCAD in this patient cohort. However, cTnI peak was a predictor of significant coronary artery disease.

Transcatheter mitral valve intervention: an emerging treatment for mitral regurgitation

Mitral regurgitation (MR) is a valvular heart disease associated with significant morbidity and mortality. Transcatheter mitral valve intervention (TMVI) repairs or replaces the mitral valve through small arterial and venous entry sites and so avoids risks associated with open heart surgery. Transcatheter devices targeting components of the mitral apparatus are being developed to repair or replace it. Numerous challenges remain including developing more adaptable devices and correction of multiple components of the mitral annulus to attain durable results. The mitral valve apparatus is a complex structure and understanding of the mechanisms of MR is essential in the development of TMVI. There will likely be a complementary role between surgery and TMVI in the near future.

Point-of-care INR compared to laboratory INR in patients supported with a continuous flow left ventricular assist device

Fig. 1. Correlation between INR as measured by CoaguChek® XS and the laboratory. Continuous-flow left ventricular assist devices (CF-LVAD) are utilised in patients with end-stage heart failure (ESHF) as a bridge to cardiac transplantation or in some countries, as destination therapy [1]. Thrombotic and bleeding events are the most frequent and serious complications in patients with CF-LVAD [2]. As such, warfarinisation and a daily reported international normalised ratio (INR) value between 2.0 and 3.0 are required to reduce the thrombotic risk [3]. The CoaguChek® XS (Roche Diagnostics, Indiana, North America) has been approved for use as a form of anticoagulation monitoring. However there is limited data in its use formonitoring anticoagulation in patients with a CF-LVAD [4]. We analysed 230 INR values, as measured by CoaguChek® XS and the laboratory (Stagos STA-R Evolution, Leicester, United Kingdom), from 15 patients with CF-LVAD for ESHF as a bridge to transplant at The Prince Charles Hospital (Brisbane, Australia) between December 2013 and August 2015. Blood samples for each of the testing methods were taken on the same day and within a 4-hour window of each other. Mean age of 40 ± 14 years. 10 (67%) were male and target INR was 2–3 for all patients. 4 (27%) were on amiodarone, mean creatinine was 89±53 μmol/L,meanhaematocrit 0.32 (+/−0.05) and nopatients had hepatic synthetic or thyroid dysfunction. There was amoderate correlation between laboratory and CoaguChek® XS INR values with a correlation coefficient of 0.86 (r2= 0.75, p b 0.001) shown in Fig. 1. Mean INR was significantly different between the laboratory and CoaguChek® XS

Transcatheter aortic valve implantation using the Lotus valve system in severe aortic stenosis in an orthotopic heart transplant patient

A 68-year-old male presented with increasing breathlessness (NYHA Class III) and reduced exercise tolerance to approximately 150 m. An orthotopic heart transplant had been performed twelve years previously for ischaemic cardiomyopathy. Transthoracic and transoesophageal echocardiography (TOE) revealed a calcified aortic valve with severe stenosis (maximum trans-aortic velocity 4.0 m/s, mean pressure gradient 44 mm Hg, aortic valve area 0.7 cm) and