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"Fairbairn, Timothy A"
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Diffusion-weighted MRI determined cerebral embolic infarction following transcatheter aortic valve implantation: assessment of predictive risk factors and the relationship to subsequent health status
by
Greenwood, John P
,
Fairbairn, Timothy A
,
Worthy, Gillian
in
acute myocardial infarction
,
Aged
,
Aged, 80 and over
2012
Background‘Silent’ cerebral infarction and stroke are complications of transcatheter aortic valve implantation (TAVI).ObjectiveTo assess the occurrence of cerebral infarction, identify predictive risk factors and examine the impact on patient health-related quality of life (HRQoL).MethodsCerebral diffusion weighted MRI of 31 patients with aortic stenosis undergoing CoreValve TAVI was carried out. HRQoL was assessed at baseline and at 30 days by SF-12v2 and EQ5D questionnaires.ResultsNew cerebral infarcts occurred in 24/31 patients (77%) and stroke in 2 (6%). Stroke was associated with a greater number and volume of cerebral infarcts. Age (r=0.37, p=0.042), severity of atheroma (arch and descending aorta; r=0.91, p<0.001, r=0.69, p=0.001, respectively) and catheterisation time (r=0.45, p=0.02) were predictors of the number of new cerebral infarcts. HRQoL improved overall: SF-12v2 physical component summary increased significantly (32.4±6.2 vs 36.5±7.2; p=0.03) with no significant change in mental component summary (43.5±11.7 vs 43.1±14.3; p=0.85). The EQ5D score and Visual Analogue Scale showed no significant change (0.56±0.26 vs 0.59±0.31; p=0.70, and 54.2±19 vs 58.2±24; p=0.43).ConclusionMultiple small cerebral infarcts occurred in 77% of patients with TAVI. The majority of infarcts were ‘silent’ with clinical stroke being associated with a both higher infarct number and volume. Increased age and the severity of aortic arch atheroma were independent risk factors for the development of new cerebral infarcts. Overall HRQoL improved and there was no association between the number of new cerebral infarcts and altered health status.
Journal Article
Sex-related differences in left ventricular remodeling in severe aortic stenosis and reverse remodeling after aortic valve replacement: A cardiovascular magnetic resonance study
by
Musa, Tarique A.
,
Blackman, Daniel J.
,
Sharples, Linda D.
in
Aged
,
Aged, 80 and over
,
Aortic Valve Stenosis - diagnosis
2016
Cardiac adaptation to aortic stenosis (AS) appears to differ according to sex, but reverse remodeling after aortic valve replacement has not been extensively described. The aim of the study was to determine using cardiac magnetic resonance imaging whether any sex-related differences exist in AS in terms of left ventricular (LV) remodeling, myocardial fibrosis, and reverse remodeling after valve replacement.
One hundred patients (men, n = 60) with severe AS undergoing either transcatheter or surgical aortic valve replacement underwent cardiac magnetic resonance scans at baseline and 6 months after valve replacement.
Despite similar baseline comorbidity and severity of AS, women had a lower indexed LV mass than did men (65.3 ± 18.4 vs 81.5 ± 21.3 g/m2, P < .001) and a smaller indexed LV end-diastolic volume (87.3 ± 17.5 vs 101.2 ± 28.6 mL/m2, P = .002) with a similar LV ejection fraction (58.6% ± 10.2% vs 54.8% ± 12.9%, P = .178). Total myocardial fibrosis mass was similar between sexes (2.3 ± 4.1 vs 1.3 ± 1.1 g, P = .714), albeit with a differing distribution according to sex. After aortic valve replacement, men had more absolute LV mass regression than did women (18.3 ± 10.6 vs 12.7 ± 8.8 g/m2, P = .007). When expressed as a percentage reduction of baseline indexed LV mass, mass regression was similar between the sexes (men 21.7% ± 10.1% vs women 18.4% ± 11.0%, P = .121). There was no sex-related difference in postprocedural LV ejection fraction or aortic regurgitation. Sex was not found to be a predictor of LV reverse remodeling on multiple regression analysis.
There are significant differences in the way that male and female hearts adapt to AS. Six months after aortic valve replacement, there are no sex-related differences in reverse remodeling, but superior reverse remodeling in men as a result of their more adverse remodeling profile at baseline.
Journal Article
Assessment of aortic stiffness by cardiovascular magnetic resonance following the treatment of severe aortic stenosis by TAVI and surgical AVR
by
Motwani, Manish
,
Sourbron, Steven P.
,
Blackman, Daniel J.
in
Aged
,
Aged, 80 and over
,
Angiology
2016
Aortic stiffness is increasingly used as an independent predictor of adverse cardiovascular outcomes. We sought to compare the impact of transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR) upon aortic vascular function using cardiovascular magnetic resonance (CMR) measurements of aortic distensibility and pulse wave velocity (PWV).
A 1.5 T CMR scan was performed pre-operatively and at 6 m post-intervention in 72 patients (32 TAVI, 40 SAVR; age 76 ± 8 years) with high-risk symptomatic severe aortic stenosis. Distensibility of the ascending and descending thoracic aorta and aortic pulse wave velocity were determined at both time points. TAVI and SAVR patients were comparable for gender, blood pressure and left ventricular ejection fraction. The TAVI group were older (81 ± 6.3 vs. 72.8 ± 7.0 years, p < 0.05) with a higher EuroSCORE II (5.7 ± 5.6 vs. 1.5 ± 1.0 %, p < 0.05). At 6 m, SAVR was associated with a significant decrease in distensibility of the ascending aorta (1.95 ± 1.15 vs. 1.57 ± 0.68 × 10−3mmHg−1, p = 0.044) and of the descending thoracic aorta (3.05 ± 1.12 vs. 2.66 ± 1.00 × 10−3mmHg−1, p = 0.018), with a significant increase in PWV (6.38 ± 4.47 vs. 11.01 ± 5.75 ms−1, p = 0.001). Following TAVI, there was no change in distensibility of the ascending aorta (1.96 ± 1.51 vs. 1.72 ± 0.78 × 10−3mmHg−1, p = 0.380), descending thoracic aorta (2.69 ± 1.79 vs. 2.21 ± 0.79 × 10−3mmHg−1, p = 0.181) nor in PWV (8.69 ± 6.76 vs. 10.23 ± 7.88 ms−1, p = 0.301) at 6 m.
Treatment of symptomatic severe aortic stenosis by SAVR but not TAVI was associated with an increase in aortic stiffness at 6 months. Future work should focus on the prognostic implication of these findings to determine whether improved patient selection and outcomes can be achieved.
Journal Article
Cardiovascular imaging research priorities
by
Fairbairn, Timothy A
,
Williams, Michelle C
,
Yong, Guo Liang
in
Artificial intelligence
,
Cardiovascular disease
,
Data science
2023
ObjectivesTwo interlinked surveys were organised by the British Heart Foundation Data Science Centre, which aimed to establish national priorities for cardiovascular imaging research.MethodsFirst a single time point public survey explored their views of cardiovascular imaging research. Subsequently, a three-phase modified Delphi prioritisation exercise was performed by researchers and healthcare professionals. Research questions were submitted by a diverse range of stakeholders to the question ‘What are the most important research questions that cardiovascular imaging should be used to address?’. Of these, 100 research questions were prioritised based on their positive impact for patients. The 32 highest rated questions were further prioritised based on three domains: positive impact for patients, potential to reduce inequalities in healthcare and ability to be implemented into UK healthcare practice in a timely manner.ResultsThe public survey was completed by 354 individuals, with the highest rated areas relating to improving treatment, quality of life and diagnosis. In the second survey, 506 research questions were submitted by diverse stakeholders. Prioritisation was performed by 90 researchers or healthcare professionals in the first round and 64 in the second round. The highest rated questions were ‘How do we ensure patients have equal access to cardiovascular imaging when it is needed?’ and ‘How can we use cardiovascular imaging to avoid invasive procedures’. There was general agreement between healthcare professionals and researchers regarding priorities for the positive impact for patients and least agreement for their ability to be implemented into UK healthcare practice in a timely manner. There was broad overlap between the prioritised research questions and the results of the public survey.ConclusionsWe have identified priorities for cardiovascular imaging research, incorporating the views of diverse stakeholders. These priorities will be useful for researchers, funders and other organisations planning future research.
Journal Article
Prognostic value of coronary computed tomography angiographic derived fractional flow reserve: a systematic review and meta-analysis
by
Jensen, Jesper M
,
Parner, Erik
,
Fairbairn, Timothy A
in
angina pectoris
,
Cardiovascular disease
,
Clinical outcomes
2022
ObjectivesTo obtain more powerful assessment of the prognostic value of fractional flow reserveCT testing we performed a systematic literature review and collaborative meta-analysis of studies that assessed clinical outcomes of CT-derived calculation of FFR (FFRCT) (HeartFlow) analysis in patients with stable coronary artery disease (CAD).MethodsWe searched PubMed and Web of Science electronic databases for published studies that evaluated clinical outcomes following fractional flow reserveCT testing between 1 January 2010 and 31 December 2020. The primary endpoint was defined as ‘all-cause mortality (ACM) or myocardial infarction (MI)’ at 12-month follow-up. Exploratory analyses were performed using major adverse cardiovascular events (MACEs, ACM+MI+unplanned revascularisation), ACM, MI, spontaneous MI or unplanned (>3 months) revascularisation as the endpoint.ResultsFive studies were identified including a total of 5460 patients eligible for meta-analyses. The primary endpoint occurred in 60 (1.1%) patients, 0.6% (13/2126) with FFRCT>0.80% and 1.4% (47/3334) with FFRCT ≤0.80 (relative risk (RR) 2.31 (95% CI 1.29 to 4.13), p=0.005). Likewise, MACE, MI, spontaneous MI or unplanned revascularisation occurred more frequently in patients with FFRCT ≤0.80 versus patients with FFRCT >0.80. Each 0.10-unit FFRCT reduction was associated with a greater risk of the primary endpoint (RR 1.67 (95% CI 1.47 to 1.87), p<0.001).ConclusionsThe 12-month outcomes in patients with stable CAD show low rates of events in those with a negative FFRCT result, and lower risk of an unfavourable outcome in patients with a negative test result compared with patients with a positive test result. Moreover, the FFRCT numerical value was inversely associated with outcomes.
Journal Article
Implementation of a national AI technology program on cardiovascular outcomes and the health system
2025
Coronary artery disease (CAD) is a major cause of ill health and death worldwide. Coronary computed tomographic angiography (CCTA) is the first-line investigation to detect CAD in symptomatic patients. This diagnostic approach risks greater second-line heart tests and treatments at a cost to the patient and health system. The National Health Service funded use of an artificial intelligence (AI) diagnostic tool, computed tomography (CT)-derived fractional flow reserve (FFR-CT), in patients with chest pain to improve physician decision-making and reduce downstream tests. This observational cohort study assessed the impact of FFR-CT on cardiovascular outcomes by including all patients investigated with CCTA during the national AI implementation program at 27 hospitals (CCTA
n
= 90,553 and FFR-CT
n
= 7,863). FFR-CT was safe, with no difference in all-cause (
n
= 1,134 (3.2%) versus 1,612 (2.9%), adjusted-hazard ratio (aHR) 1.00 (0.93–1.08),
P
= 0.97) or cardiovascular mortality (
n
= 465 (1.3%) versus 617 (1.1%), aHR 0.96 (0.85–1.08),
P
= 0.48), while reducing invasive coronary angiograms (
n
= 5,720 (16%) versus 8,183 (14.9%), aHR 0.93 (0.90–0.97),
P
< 0.001) and noninvasive cardiac tests (189/1,000 patients versus 167/1,000),
P
< 0.001). Implementation of an AI-diagnostic tool as part of a health intervention program was safe and beneficial to the patient pathway and health system with fewer cardiac tests at 2 years.
National implementation of a computed tomographic angiography and AI-diagnostic tool, CT-derived fractional flow reserve (FFR-CT), did not provide significant benefits in reducing mortality but led to fewer invasive coronary angiograms and downstream cardiac tests.
Journal Article
Reperfusion haemorrhage as determined by cardiovascular MRI is a predictor of adverse left ventricular remodelling and markers of late arrhythmic risk
by
Greenwood, John P
,
Fairbairn, Timothy A
,
Mather, Adam N
in
Acquisitions & mergers
,
Adult
,
Aged
2011
BackgroundInterstitial haemorrhage due to reperfusion of severely ischaemic myocardium can be detected in vivo by T2-weighted (T2W) and T2* cardiovascular magnetic resonance (CMR). The clinical implications of myocardial haemorrhage following primary percutaneous coronary intervention (PPCI) remain undetermined.ObjectivesTo assess whether the presence of myocardial haemorrhage influences ventricular remodelling and risk of late ventricular arrhythmia following PPCI for acute myocardial infarction (AMI).MethodsForty-eight patients with first ST-elevation AMI, treated successfully with PPCI, underwent CMR at day 2 and 3 months. Left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV) and left ventricular ejection fraction (LVEF) were determined from cine-CMR, infarct size and microvascular obstruction (MVO) from gadolinium-enhanced images and area at risk (AAR) from T2W CMR. Myocardial haemorrhage was defined as hypointense signal within the AAR on both T2W and T2* images. All patients had a signal-averaged electrocardiogram at 3 months.Results30/48 (63%) patients had MVO and 12 of these showed myocardial haemorrhage. Patients with haemorrhagic myocardial infarction (MI) had significantly larger LVEDV and LVESV, lower LVEF and larger infarcts than those with non-haemorrhagic MI at baseline and at 3 months. The presence of haemorrhage was an independent predictor of adverse remodelling defined as increased LVESV on follow-up (p=0.001, OR 1.6) and prolonged filtered QRS (fQRS) on signal-averaged ECG at 3 months (p=0.020, OR 1.176).ConclusionsReperfusion haemorrhage following AMI is associated with larger infarct size, diminished myocardial salvage and lower LVEF. The presence of haemorrhage is the strongest independent predictor of adverse ventricular remodelling and is also associated with prolonged fQRS duration, which is a marker of arrhythmic risk.
Journal Article
Assessment of valve haemodynamics, reverse ventricular remodelling and myocardial fibrosis following transcatheter aortic valve implantation compared to surgical aortic valve replacement: a cardiovascular magnetic resonance study
by
Greenwood, John P
,
Motwani, Manish
,
Fairbairn, Timothy A
in
Age Factors
,
Aged
,
Aged, 80 and over
2013
Objective To compare the effects of transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR) on aortic valve haemodynamics, ventricular reverse remodelling and myocardial fibrosis (MF) by cardiovascular magnetic resonance (CMR) imaging. Design A 1.5 T CMR scan was performed preoperatively and 6 months postoperatively. Setting University hospitals of Leeds and Leicester, UK. Patients 50 (25 TAVI, 25 SAVR; age 77±8 years) high-risk severe symptomatic aortic stenosis (AS) patients. Main outcome measures Valve haemodynamics, ventricular volumes, ejection fraction (EF), mass and MF. Results Patients were matched for gender and AS severity but not for age (80±6 vs 73±7 years, p=0.001) or EuroSCORE (22±14 vs 7±3, p<0.001). Aortic valve mean pressure gradient decreased to a greater degree post-TAVI compared to SAVR (21±8 mm Hg vs 35±13 mm Hg, p=0.017). Aortic regurgitation reduced by 8% in both groups, only reaching statistical significance for TAVI (p=0.003). TAVI and SAVR improved (p<0.05) left ventricular (LV) end-systolic volumes (46±18 ml/m2 vs 41±17 ml/m2; 44±22 ml/m2 vs32±6 ml/m2) and mass (83±20 g/m2 vs 65±15 g/m2; 74±11 g/m2 vs 59±8 g/m2). SAVR reduced end-diastolic volumes (92±19 ml/m2 vs 74±12 ml/m2, p<0.001) and TAVI increased EF (52±12% vs 56±10%, p=0.01). MF reduced post-TAVI (10.9±6% vs 8.5±5%, p=0.03) but not post-SAVR (4.2±2% vs 4.1±2%, p=0.98). Myocardial scar (p≤0.01) and baseline ventricular volumes (p<0.001) were the major predictors of reverse remodelling. Conclusions TAVI was comparable to SAVR at LV reverse remodelling and superior at reducing the valvular pressure gradient and MF. Future work should assess the prognostic importance of reverse remodelling and fibrosis post-TAVI to aid patient selection.
Journal Article
The cost-effectiveness of transcatheter aortic valve implantation versus surgical aortic valve replacement in patients with severe aortic stenosis at high operative risk
by
Greenwood, John P
,
Fairbairn, Timothy A
,
Meads, David M
in
Aortic Valve Stenosis - diagnosis
,
Aortic Valve Stenosis - economics
,
Aortic Valve Stenosis - mortality
2013
Objective To determine the cost-effectiveness of transcatheter aortic valve implantation (TAVI) compared with surgical aortic valve replacement (SAVR) in a high-risk aortic stenosis (AS) population. Design A cost-utility analysis employing the National Institute of Clinical Excellence (NICE) reference case design for technology appraisals. Setting The perspective of the UK National Health Service. Patients Utility data from a UK high-risk AS population. TAVI and SAVR effectiveness was taken from the PARTNER A randomised controlled trial. Main outcome measures Costs modelled over a 10 year horizon using a Markov model. Incremental cost-effectiveness ratios and cost-effectiveness acceptability curve were calculated with reference to the NICE willingness to pay per quality adjusted life year (QALY) gain threshold. Deterministic and probabilistic sensitivity analyses performed. Results Despite greater procedural costs (£16 500 vs £9,256), TAVI was cost-effective compared with SAVR over the 10 year model horizon (costs £52 593 vs £53 943 and QALYs 2.81 vs 2.75), indicating that TAVI dominated SAVR. This appeared to be due to greater postsurgical costs, related to the length and cost of hospital stay. The results appeared robust to a number of deterministic sensitivity and probabilistic analyses. The cost-effectiveness acceptability curve indicated that at the NICE £20 000 willingness to pay threshold per QALY gained, TAVI had a 64.6% likelihood of being cost-effective, compared with 35.4% for SAVR. Conclusions TAVI is likely to be a cost-effective treatment for high-risk patients with AS compared with the reference standard of SAVR. However, uncertainty surrounding the long-term outcomes for TAVI patients remains; this could have a substantive impact on estimates of cost-effectiveness.
Journal Article
Coronary Volume to Left Ventricular Mass Ratio in Patients With Hypertension
by
Marsan, Nina Ajmone
,
Sonck, Jeroen
,
Rogers, Campbell
in
Angiography
,
Blood pressure
,
Body mass index
2023
The coronary vascular volume to left ventricular mass (V/M) ratio assessed by coronary computed tomography angiography (CCTA) is a promising new parameter to investigate the relation of coronary vasculature to the myocardium supplied. It is hypothesized that hypertension decreases the ratio between coronary volume and myocardial mass by way of myocardial hypertrophy, which could explain the detected abnormal myocardial perfusion reserve reported in patients with hypertension. Individuals enrolled in the multicenter ADVANCE (Assessing Diagnostic Value of Noninvasive FFRCT in Coronary Care) registry who underwent clinically indicated CCTA for analysis of suspected coronary artery disease with known hypertension status were included in current analysis. The V/M ratio was calculated from CCTA by segmenting the coronary artery luminal volume and left ventricular myocardial mass. In total, 2,378 subjects were included in this study, of whom 1,346 (56%) had hypertension. Left ventricular myocardial mass and coronary volume were higher in subjects with hypertension than normotensive patients (122.7 ± 32.8 g vs 120.0 ± 30.5 g, p = 0.039, and 3,105.0 ± 992.0 mm3 vs 2,965.6 ± 943.7 mm3, p <0.001, respectively). Subsequently, the V/M ratio was higher in patients with hypertension than those without (26.0 ± 7.6 mm3/g vs 25.3 ± 7.3 mm3/g, p = 0.024). After correcting for potential confounding factors, the coronary volume and ventricular mass remained higher in patients with hypertension (least square) mean difference estimate: 196.3 (95% confidence intervals [CI] 119.9 to 272.7) mm3, p <0.001, and 5.60 (95% CI 3.42 to 7.78) g, p <0.001, respectively), but the V/M ratio was not significantly different (least square mean difference estimate: 0.48 (95% CI −0.12 to 1.08) mm3/g, p = 0.116). In conclusion, our findings do not support the hypothesis that the abnormal perfusion reserve would be caused by reduced V/M ratio in patients with hypertension.
Journal Article