ORCID Profile
0000-0002-9173-5904
Current Organisation
Alfred Health
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Publisher: Elsevier BV
Date: 08-2020
DOI: 10.1016/J.HLC.2019.12.001
Abstract: Transcatheter aortic valve implantation (TAVI) has been shown to be a safe and effective alternative to surgical aortic valve replacement (SAVR) in high- and intermediate-risk patients with severe aortic stenosis. TAVI for patients at lower risk of periprocedural mortality has not been extensively investigated. We aimed to describe outcomes in low-, intermediate- and high-risk patients undergoing TAVI in a multicentre Australian study. We evaluated data from 601 patients who underwent TAVI at two hospitals in Melbourne, from August 2008 to February 2018. Patients were stratified according to low risk (STS 8%). Outcomes were reported according to Valve Academic Research Consortium-2 (VARC-2) criteria. Mean age was 84±5 years and 49% were female. Two hundred and eighty-five (285) (47%) patients were low-risk, 243 (40%) were intermediate risk and 73 (12%) were high risk. Thirty-day (30-) mortality was low in all three groups (1.1%, 1.7% and 1.4%, respectively, p=0.8). Similarly, patients had a low risk of disabling stroke (0.4%, 1.3%, 0%, p=0.8). Rates of post-procedural permanent pacemaker were also similar (21%, 27%, 26%, p=0.5). At least moderate aortic regurgitation occurred in 9% of patients at discharge with no significant differences between groups. In this large Australian multicentre cohort of TAVI patients, 30-day mortality, and post-procedural outcomes were excellent and similar across the patient-risk spectrum. Our study offers further support for the safety of TAVI in low-risk populations and demonstrates the limitations of the STS score.
Publisher: Oxford University Press (OUP)
Date: 02-12-2022
Abstract: Increasing transcatheter aortic valve implantation (TAVI) rates have resulted in prolonged waiting times. These have been associated with heart failure hospitalizations (HFH) and mortality yet sex differences have not yet been reported. All patients who underwent TAVI for severe aortic stenosis at a tertiary referral hospital in Australia were prospectively included. Total waiting time was ided into ‘work-up’ waiting time (period from referral date until heart team approval) and, ‘procedural’ waiting time (period from heart team approval until procedure date). Patients were analysed according to sex. Cohorts were matched to correct for differences in baseline and procedural variables. The primary endpoints were waiting times. Secondary outcomes included a composite of 30-day mortality and HFH, quality of life, and mobility. A total of 407 patients (42% women) were included. After matching of the two cohorts (345 patients), women had significantly longer total waiting times than men: median 156 [interquartile range (IQR) 114–220] days in women vs. 147 [IQR 92–204] days in men (P = 0.037) including longer work-up (83 [IQR 50–128] vs. 71 [IQR 36–119], P = 0.15) and procedural waiting times (65 [IQR 44–100] vs. 58 [IQR 30–93], P = 0.042). Increasing waiting times were associated with higher 30-day mortality and HFH (P = 0.01 for work-up waiting time, P = 0.02 for procedural waiting time) and decreased 30-day mobility (P = 0.044 for procedural waiting time) in women, but not in men. TAVI waiting times are significantly longer in women compared to men and are associated with increased mortality and HFH and reduced mobility at 30-days.
Publisher: Elsevier BV
Date: 05-2022
DOI: 10.1016/J.HLC.2021.10.025
Abstract: To assess whether outcomes following percutaneous coronary intervention (PCI) versus coronary artery bypass grafting (CABG) for left main coronary artery (LMCA) disease differ between men and women. Current guidelines recommend either PCI or CABG for patients with unprotected LMCA disease and low-to-intermediate anatomical complexity. However, it is unclear whether these guidelines apply to women, who are underrepresented in clinical trials. An electronic search was performed to identify studies reporting sex-specific outcomes after PCI versus CABG in patients with LMCA disease. Trial level hazard ratios (HRs) and 95% confidence intervals (CIs) were pooled by random-effects modelling. Eight (8) studies met inclusion criteria, comprising 13,066 patients (24.3% women). In both sexes, there was no difference between PCI and CABG with respect to the primary composite endpoint of death, myocardial infarction or stroke (HR in women: 1.03, 95% CI 0.76-1.40 HR in men: 1.04, 95% CI 0.92-1.17). However, both sexes were more likely to require repeat revascularisation after PCI. There was no interaction between sex and treatment effect for the primary composite endpoint nor for the in idual outcomes of death, stroke and repeat revascularisation. However, in women the risk of myocardial infarction was higher after PCI compared with CABG (HR 1.84, 95% CI 1.06-3.18), with a trend toward the opposite in men (HR 0.78, 95% CI 0.54-1.13 p-interaction=0.01). Percutaneous coronary intervention and CABG have a comparable risk of the composite outcome of death, stroke or myocardial infarction in patients undergoing revascularisation for LMCA disease, with no significant interaction between sex and treatment effect.
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 05-2021
DOI: 10.1161/CIRCOUTCOMES.120.006789
Abstract: There is increasing evidence that use of intravascular ultrasound (IVUS) guidance during percutaneous coronary intervention (PCI) is associated with improved clinical outcomes compared with angiography guidance alone. However, concern regarding the cost-effectiveness of IVUS has limited use of this technology worldwide. In this study, we aimed to evaluate the cost-effectiveness of IVUS-guided PCI compared with angiography-guided PCI in patients undergoing drug-eluting stent implantation. A decision-analytic Markov model was constructed to compare the cost-effectiveness of IVUS to angiography guidance from the Australian healthcare system perspective. Procedure-related morbidity and mortality were estimated from the literature. Costs were obtained from Australian sources. The population of interest was all-comers undergoing PCI with drug-eluting stent. Outcomes of interest included costs, life-expectancy, and quality-adjusted life years (QALYs) for both treatment groups. In the base case, IVUS guidance was cost-effective compared with angiography guidance alone. With 5% annual discounting, IVUS was associated with increased lifetime costs of Australian dollars (AUD) $823 (USD $597) per person and benefits of 0.04 life years and 0.05 QALYs compared with angiography, yielding an incremental cost-effectiveness ratio of AUD $17 539 (USD $12 730) per QALY gained. Results were robust to sensitivity analyses, with IVUS being cost-effective in 99% of 10 000 Monte Carlo iterations assuming a willingness-to-pay threshold of AUD $50 000 per QALY gained. In a worst-case scenario analysis, IVUS remained the cost-effective option, with an ICER of AUD $36 651 (USD $26 601) per QALY gained. Exploratory subgroup analysis revealed that cost-effectiveness may be greatest among patients with left main and complex coronary lesions. Use of IVUS guidance during PCI is likely to be cost-effective compared with angiography guidance alone among patients undergoing drug-eluting stent implantation.
Publisher: Elsevier BV
Date: 06-2020
Publisher: Ovid Technologies (Wolters Kluwer Health)
Date: 21-02-2023
Abstract: In patients with aortic stenosis (AS), the presence of mitral regurgitation (MR) can lead to underestimation of AS severity and worse clinical outcomes. The objective of this study was to characterize the magnitude of the effects of concomitant MR on hemodynamic indicators of AS severity using clinical data and a computational cardiovascular simulation. Echocardiographic data from 1427 patients with severe AS were used to inform a computational cardiovascular system model, and varying degrees of MR and AS were simulated. Hemodynamic data, including left ventricular and aortic pressure waveforms, were generated for all simulations. Simulated reduction in mean transaortic pressure gradient (MPG) associated with MR was then used to calculate the adjusted MPG in the clinical cohort. MR was present in 861 (60%) patients. Compared with patients without MR, patients with MR had a lower aortic‐valve area (0.83±0.2 cm 2 versus 0.75±0.2 P .001) and were more likely to have a low‐gradient pattern (MPG mm Hg) (45% versus 54% P .001). Simulations showed that the presence of concomitant mild, moderate, and severe MR with AS was accompanied by a mean reduction in MPG of 10%, 29%, and 40%, respectively. For patients with MR, their calculated adjusted MPG was on average 24% higher than their MPG (52±22 versus 42±16 mm Hg). Of the 467 patients with low‐gradient AS and MR, 240 (51%) would reclassify as high gradient based on their adjusted MPG. Concomitant MR results in lower MPG and reduced forward flow compared with isolated AS. Careful quantitation of MR should be factored into the assessment of AS severity to mitigate for potential underestimation.
No related grants have been discovered for Antony Walton.