Imperial College London

DrJamesHoward

Faculty of MedicineNational Heart & Lung Institute

Clinical Lecturer
 
 
 
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james.howard1 Website CV

 
 
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Block B Hammersmith HospitalHammersmith Campus

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Summary

 

Publications

Publication Type
Year
to

143 results found

Nowbar AN, Rajkumar C, Foley M, Ahmed-Jushuf F, Howard JP, Seligman H, Petraco R, Sen S, Nijjer SS, Shun-Shin MJ, Keeble TR, Sohaib A, Collier D, McVeigh P, Harrell FE, Francis DP, Al-Lamee RKet al., 2022, A double-blind randomised placebo-controlled trial of percutaneous coronary intervention for the relief of stable angina without antianginal medications: design and rationale of the ORBITA-2 trial., EuroIntervention, Vol: 17, Pages: 1490-1497

Percutaneous coronary intervention (PCI) is frequently performed for stable angina. However, the first blinded trial, ORBITA, did not show a placebo-controlled increment in exercise time in patients with single-vessel disease, at 6 weeks, on maximal antianginal therapy. ORBITA-2 will assess the placebo-controlled efficacy of PCI on angina frequency in patients with single- or multivessel disease, at 12 weeks, on no antianginal therapy. ORBITA-2 is a double-blind placebo-controlled trial randomising participants with (i) angina at presentation, (ii) documented angina during the 2-week pre-randomisation symptom assessment phase, (iii) objective evidence of ischaemia, (iv) single- or multivessel disease, and (v) clinical eligibility for PCI. At enrolment, antianginals will be stopped, and angina questionnaires completed. Participants will record their symptoms on a smartphone application daily throughout the trial and will undergo exercise treadmill testing and stress echocardiography at pre-randomisation. They will then undergo coronary angiography with unblinded invasive physiology assessment. Eligible participants will then be sedated to a deep level of conscious sedation and randomised 1:1 between PCI and placebo. After the 12-week blinded follow-up period, they will return for questionnaires, exercise testing and stress echocardiography assessment. If angina becomes intolerable, antianginals will be introduced using a prespecified medication protocol. The primary outcome is an angina symptom score using an ordinal clinical outcome scale for angina. Secondary outcomes include exercise treadmill time, angina frequency, angina severity and quality of life. Trial registration: ClinicalTrials.gov: NCT03742050.

Journal article

Kelshiker M, Seligman H, Howard JAMES, Rahman H, Foley M, Nowbar A, Rajkumar C, Shun-Shin M, Ahmad Y, Sen S, Al-Lamee R, Cole G, Hoole S, Morris P, Rigo F, Mayet J, Francis D, Petraco Ret al., 2022, Coronary flow reserve and cardiovascular outcomes: a systematic review and meta-analysis, European Heart Journal, Vol: 43, Pages: 1582-1593, ISSN: 0195-668X

Aims: This meta-analysis aims to quantify the association of reduced coronary flow with all3 cause mortality and major adverse cardiovascular events (MACE) across a broad range of patient groups and pathologies. Methods and Results: We systematically identified all studies between 1st January 2000 and1st August 2020, where coronary flow was measured and clinical outcomes were reported. The endpoints were all-cause mortality and MACE. Estimates of effect were calculated from published hazard ratios using a random-effects model. 79 studies, including 59,740 subjects were included. Abnormal coronary flow reserve (CFR) was associated with a higher incidence of all-cause mortality (HR 3.78, 95% CI 2.39-5.97) and a higher incidence of MACE (HR 3.42, 95% CI 2.92-3.99). Each 0.1-unit reduction in CFR was associated with a proportional increase in mortality (per 0.1 CFR unit HR 1.16, 95% CI 1.04-1.29) and MACE (per 0.1 CFR unit HR 1.08, 95% CI 1.04-1.11)). In patients with isolated coronary microvascular dysfunction, an abnormal CFR was associated with a higher incidence of mortality (HR 5.44, 95% CI 3.78-7.83) and MACE (HR 3.56, 95% CI 2.14-5.90). Abnormal CFR was also associated with a higher incidence of MACE in patients with acute coronary syndromes (HR 3.76, 95% CI 2.35-6.00), heart failure (HR 6.38, 95% CI 1.95-20.90), heart transplant (HR 3.32, 95% CI 2.34-4.71) and diabetes mellitus (HR 7.47, 95% CI 3.37-16.55). Conclusions: Reduced coronary flow is strongly associated with increased risk of all-cause mortality and MACE across a wide range of pathological processes. This finding supports recent recommendations that coronary flow should be measured more routinely in clinical practice to target aggressive vascular risk modification for individuals at higher risk

Journal article

Foley M, Hall K, Howard J, Ahmad Y, Gandhi M, Mahboobani S, Okafor J, Rahman H, Hadjiloizou N, Ruparelia N, Mikhail G, Malik I, Kanaganayagam G, Sutaria N, Rana B, Ariff B, Barden E, Anderson J, Afoke J, Petraco R, Al-Lamee R, Sen Set al., 2022, Aortic valve calcium score is associated with acute stroke in TAVI patients, Journal of the Society for Cardiovascular Angiography & Interventions, ISSN: 2772-9303

Journal article

Kelshiker M, Seligman H, Howard J, Petraco Ret al., 2022, The importance of time-to-event analysis in measuring the prognostic impact of coronary flow reserve, European Heart Journal, ISSN: 0195-668X

Journal article

Ribeiro HDM, Arnold A, Howard JP, Shun-Shin MJ, Zhang Y, Francis DP, Lim PB, Whinnett Z, Zolgharni Met al., 2022, ECG-based real-time arrhythmia monitoring using quantized deep neural networks: A feasibility study, COMPUTERS IN BIOLOGY AND MEDICINE, Vol: 143, ISSN: 0010-4825

Journal article

Rajkumar CA, Ganesananthan S, Ahmad Y, Seligman H, Thornton GD, Foley M, Nowbar AN, Howard JP, Francis DP, Keeble TR, Grunwald IQ, Al-Lamee RK, Malik I, Shun-Shin MJet al., 2022, Mechanical thrombectomy with retrievable stents and aspiration catheters for acute ischaemic stroke: a meta-analysis of randomised controlled trials., EuroIntervention, Vol: 17, Pages: e1425-e1434

BACKGROUND: Retrievable stents and aspiration catheters have been developed to provide more effective arterial recanalisation in acute ischaemic stroke. AIMS: The aim of this analysis was to test the effect of mechanical thrombectomy on mortality and long-term neurological outcome in patients presenting with acute large-vessel anterior circulation ischaemic stroke. METHODS: A structured search identified randomised controlled trials of thrombectomy (using a retrievable stent or aspiration catheter) versus control on a background of medical therapy which included intravenous thrombolysis if appropriate. The primary endpoint was disability at 90-day follow-up as assessed by the modified Rankin scale (mRS). Secondary endpoints included all-cause mortality and symptomatic intracranial haemorrhage. A Bayesian mixed-effects model was used for analysis. RESULTS: Twelve trials met the inclusion criteria, comprising a total of 1,276 patients randomised to thrombectomy and 1,282 patients to control. Randomisation to thrombectomy significantly reduced disability at 90 days (odds ratio [OR] 0.52, 95% credible interval [CrI] 0.46 to 0.61, probability(control better)<0.0001). Furthermore, thrombectomy reduced the odds of functional dependence at 90 days, indicated by an mRS score >2 (OR 0.44, CrI 0.37 to 0.52, p<0.0001). Thrombectomy reduced all-cause mortality at 90 days (16.1% vs 19.2%, OR 0.81, 95% CrI 0.66 to 0.99, p=0.024). The frequency of symptomatic intracranial haemorrhage was similar between thrombectomy (4.2%) and control (4.0%) (OR 1.12, 95% CrI 0.76 to 1.68, p=0.72). CONCLUSIONS: In patients with an acute anterior circulation stroke, modern device thrombectomy significantly reduces death and subsequent disability. The magnitude of these effects suggests that universal access to this treatment strategy should be the standard of care.

Journal article

Ahmad Y, Howard JP, Madhavan M, Bangalore S, Stone GWet al., 2022, Reporting data from meta-analysis: snapshot of a moving target, EUROPEAN HEART JOURNAL, Vol: 43, Pages: 699-700, ISSN: 0195-668X

Journal article

Seligman H, Nijjer SS, van de Hoef TP, de Waard GA, Mejia-Renteria H, Echavarria-Pinto M, Shun-Shin MJ, Howard JP, Cook CM, Warisawa T, Ahmad Y, Androshchuk V, Rajkumar C, Nowbar A, Kelshiker MA, van Lavieren MA, Meuwissen M, Danad I, Knaapen P, Sen S, Al-Lamee R, Mayet J, Escaned J, Piek JJ, van Royen N, Davies JE, Francis DP, Petraco Ret al., 2022, Phasic flow patterns of right versus left coronary arteries in patients undergoing clinical physiological assessment, EUROINTERVENTION, Vol: 17, Pages: 1260-+, ISSN: 1774-024X

Journal article

Ahmad Y, Kane C, Arnold AD, Cook C, Keene D, Shun-Shin M, Cole G, Al-Lamee R, Francis D, Howard Jet al., 2022, Randomized blinded placebo-controlled trials of renal sympathetic denervation for hypertension: a meta-analysis, Cardiovascular Revascularization Medicine, Vol: 34, Pages: 112-118, ISSN: 1553-8389

BackgroundThe efficacy of renal denervation has been controversial, but the procedure has now undergone several placebo-controlled trials. New placebo-controlled trial data has recently emerged, with longer follow-up of one trial and the full report of another trial (which constitutes 27% of the total placebo-controlled trial data). We therefore sought to evaluate the effect of renal denervation on ambulatory and office blood pressures in patients with hypertension.MethodsWe systematically identified all blinded placebo-controlled randomized trials of catheter-based renal denervation for hypertension. The primary efficacy outcome was ambulatory systolic blood pressure change relative to placebo. A random-effects meta-analysis was performed.Results6 studies randomizing 1232 patients were eligible. 713 patients were randomized to renal denervation and 519 to placebo. Renal denervation significantly reduced ambulatory systolic blood pressure (−3.52 mmHg; 95% CI −4.94 to −2.09; p < 0.0001), ambulatory diastolic blood pressure (−1.93 mmHg; 95% CI −3.04 to −0.83, p = 0.0006), office systolic blood pressure size (−5.10 mmHg; 95% CI −7.31 to −2.90, p < 0.0001) and office diastolic pressure (effect size −3.11 mmHg; 95% CI −4.43 to −1.78, p < 0.0001). Adverse events were rare and not more common with denervation.ConclusionsThe totality of blinded, randomized placebo-controlled data shows that renal denervation is safe and provides genuine reduction in blood pressure for at least 6 months post-procedure. If this effect continues in the long term, renal denervation might provide a life-long 10% relative risk reduction in major adverse cardiac events and 7.5% relative risk reduction in all-cause mortality.

Journal article

Ahmad Y, Howard J, Madhavan MV, Leon MB, Makkar RRet al., 2022, Single versus dual antiplatelet therapy after transcatheter aortic valve replacement: a meta-analysis of randomized clinical trials, Cardiovascular Revascularization Medicine, Vol: 34, Pages: 46-53, ISSN: 1553-8389

BackgroundGuidelines recommend dual antiplatelet therapy (DAPT) after transcatheter aortic valve replacement (TAVR) but guidelines predate the publication of the largest randomized trial. There have been few trials in the field to date, and with a small number of total patients; pooling their results may therefore be helpful.MethodsWe systematically identified all randomized trials comparing SAPT to DAPT after TAVR. The primary endpoint was the risk of major bleeding. Secondary endpoints included all bleeding, life-threatening bleeding, stroke, myocardial infarction, death and cardiac death.ResultsFour trials, randomizing 1086 participants, were eligible (541 randomized to SAPT and 545 randomized to DAPT). The weighted mean follow-up was 9.1 months. The risk of major bleeding was significantly increased after DAPT (relative risk (RR) 2.36, 95% confidence interval (CI) 1.27 to 4.40, P = 0.007). There was a similar increased risk for all bleeding (RR 1.65, 95% CI 1.24 to 2.19, P < 0.001), although not for life-threatening bleeding (RR 1.44, 95% CI 0.74 to 2.77, P = 0.282). There were no significant differences in the risk of stroke, myocardial infarction (MI), death or cardiac death. There was no heterogeneity observed for any endpoint (I2 = 0.0%).ConclusionsDAPT after TAVR is associated with an increased risk of major bleeding and all bleeding. There is no evidence of a significant difference between DAPT or SAPT for the risks of stroke, MI, death or cardiac death. However, the total number of patients randomized is small and the duration of follow-up is short. Larger scale randomized trials with longer follow-up are required to assess for any potential differences in ischemic endpoints or mortality.

Journal article

Zaman S, Petri C, Vimalesvaran K, Howard J, Bharath A, Francis D, Peters N, Cole GD, Linton Net al., 2022, Automatic diagnosis labeling of cardiovascular MRI by using semisupervised natural language processing of text reports, Radiology: Artificial Intelligence, Vol: 4, ISSN: 2638-6100

A semisupervised natural language processing (NLP) algorithm, based on bidirectional transformers, accurately categorized diagnoses from cardiac MRI text of radiology reports for the labeling of MR images; the model had a higher accuracy than traditional NLP models and performed faster labeling than clinicians.

Journal article

Ahmad Y, Francis DP, Bhatt DL, Howard JP, Ahmad Y, Francis D, Bhatt D, Howard Jet al., 2021, Renal Denervation for Hypertension A Systematic Review and Meta-Analysis of Randomized, Blinded, Placebo-Controlled Trials, JACC-CARDIOVASCULAR INTERVENTIONS, Vol: 14, Pages: 2614-2624, ISSN: 1936-8798

Journal article

Kellman P, Xue H, Chow K, Howard J, Chacko L, Cole G, Fontana Met al., 2021, Bright-blood and dark-blood phase sensitive inversion recovery late gadolinium enhancement and T1 and T2 maps in a single free-breathing scan: an all-in-one approach, JOURNAL OF CARDIOVASCULAR MAGNETIC RESONANCE, Vol: 23, ISSN: 1097-6647

Journal article

Howard J, Zaman S, Francis D, Cole Get al., 2021, INTELLIGENT LOCALISERS: AN INTEGRATED TIME-SAVING DEEP LEARNING SOLUTION FOR THE PLANNING OF CINE IMAGING AND IDENTIFICATION OF UNEXPECTED FINDINGS FROM A SINGLE TRANSAXIAL STACK, Annual Meeting of the British-Society-of-Cardiovascular-Magnetic-Resonance (BSCMR), Publisher: BMJ PUBLISHING GROUP, Pages: A5-A6, ISSN: 1355-6037

Conference paper

Ahmad Y, Madhavan M, Stone GW, Francis DP, Makkar R, Bhatt DL, Howard JPet al., 2021, Sodium-glucose cotransporter 2 inhibitors in patients with heart failure: a systematic review and meta-analysis of randomized trials, EUROPEAN HEART JOURNAL-QUALITY OF CARE AND CLINICAL OUTCOMES, ISSN: 2058-5225

Journal article

Stowell C, Howard J, Demetrescu C, Bhattacharyya S, Mangion K, Vimalesvaran K, Cole G, Rajani R, Sehmi J, Alzetani M, Zolgharni M, Rana B, Francis D, Shun-Shin Met al., 2021, Fully automated global longitudinal strain assessment using artificial intelligence developed and validated by a UK-wide echocardiography expert collaborative, Publisher: OXFORD UNIV PRESS, Pages: 2-2, ISSN: 0195-668X

Conference paper

Stowell C, Howard J, Cole G, Ananthan K, Demetrescu C, Pearce K, Rajani R, Sehmi J, Vimalesvaran K, Kanaganayagam S, Ghosh A, Chambers J, Rana B, Francis D, Shun-Shin Met al., 2021, Automated left ventricular dimension assessment using artificial intelligence, Publisher: OXFORD UNIV PRESS, Pages: 1-1, ISSN: 0195-668X

Conference paper

Arnold AD, Shun-Shin MJ, Ali N, Keene D, Howard JP, Chow J-J, Qureshi NA, Koa-Wing M, Tanner M, Lefroy DC, Linton NWF, Ng FS, Lim PB, Peters NS, Kanagaratnam P, Francis DP, Whinnett ZIet al., 2021, Left ventricular activation time and pattern are preserved with both selective and non-selective his bundle pacing, Heart Rhythm O2, Vol: 2, Pages: 439-445, ISSN: 2666-5018

BackgroundHis bundle pacing (HBP) can be achieved in two ways: selective HBP (S-HBP), where the His bundle is captured alone, and non-selective HBP (NS-HBP), where local myocardium is also captured resulting a pre-excited ECG appearance.ObjectiveWe assessed the impact of this ventricular pre-excitation on left and right ventricular dys-synchrony.MethodsWe recruited patients who displayed both S-HBP and NS-HBP. We performed non-invasive epicardial electrical mapping for left and right ventricular activation time (LVAT and RVAT) and pattern.Results20 patients were recruited. In the primary analysis, the mean within-patient change in LVAT from S-HBP to NS-HBP was -5.5ms (95% confidence interval: -0.6 to -10.4, non-inferiority p<0.0001). NS-HBP did not prolong RVAT (4.3ms, -4.0 to 12.8, p=0.296) but did prolong QRS duration (QRSd, 22.1ms, 11.8 to 32.4, p = 0.0003). In patients with narrow intrinsic QRS (n=6), NS-HBP preserved LVAT (-2.9ms, -9.7 to 4.0, p=0.331) but prolonged QRS duration (31.4ms, 22.0 to 40.7, p=0.0003) and mean RVAT (16.8ms, -5.3 to 38.9, p=0.108) compared to S-HBP. Activation pattern of the left ventricular surface was unchanged between S-HBP and NS-HBP but NS-HBP produced early basal right ventricular activation that was not seen in S-HBP.ConclusionCompared to S-HBP, local myocardial capture during NS-HBP produces pre-excitation of the basal right ventricle resulting in QRS duration prolongation. However, NS-HBP preserves the left ventricular activation time and pattern of S-HBP. Left ventricular dys-synchrony is not an important factor when choosing between S-HBP and NS-HBP in most patients.

Journal article

Howard J, Wood F, Finegold J, Nowbar A, Thompson DM, Arnold A, Rajkumar C, Connolly S, Cegla J, Stride C, Sever P, Northon C, Thom S, Shun-Shin M, Francis Det al., 2021, Side effect patterns in a crossover trial of statin, placebo and no treatment, Journal of the American College of Cardiology, Vol: 78, Pages: 1210-1222, ISSN: 0735-1097

BackgroundMost people who begin statins abandon them, most commonly because of side-effects. ObjectivesAssess daily symptom scores on statin, placebo and no treatment in participants who had abandoned statins.MethodsParticipants received 12 one-month medication bottles, 4 containing atorvastatin 20mg, 4 placebo and 4 empty. We measured daily symptom intensity for each using an app (scale 1-100). We also measured the nocebo ratio: the ratio of symptoms induced by taking statin that was also induced by taking placebo. Results60 participants were randomized and 49 completed the 12-month protocol. Mean symptom score was 8.0 (95% confidence interval 4.7 to 11.3) in no-tablet months. It was higher in statin months (16.3, 13.0 to 19.6, p<0.001), but also in placebo months (15.4, 12.1 to 18.7, p<0.001), with no difference between the two (p=0.388). The corresponding nocebo ratio was 0.90.In the individual-patient daily data, neither symptom intensity on starting (odds ratio 1.02, 95% CI 0.98 to 1.06, p=0.28) nor extent of symptom relief on stopping (1.01, 95% CI 0.98 to 1.05, p=0.48) distinguished between statin and placebo.Stopping was no more frequent for statin than placebo (p=0.173), and subsequent symptom relief was similar between statin and placebo.6 months after the trial, 30/60 (50%) of participants were back taking statins. ConclusionsThe majority of symptoms caused by statin tablets were nocebo. Clinicians should not interpret symptom intensity or timing of symptom onset or offset (on starting or stopping statin tablets) as indicating pharmacological causation, because the pattern is identical for placebo.

Journal article

Cook CM, Howard JP, Ahmad Y, Shun-Shin MJ, Sethi A, Clesham GJ, Tang KH, Nijjer SS, Kelly PA, Davies JR, Malik IS, Kaprielian R, Mikhail G, Petraco R, Warisawa T, Al-Janabi F, Karamasis G, Mohdnazri S, Gamma R, Stathogiannis KE, de Waard GA, Al-Lamee R, Keeble TR, Mayet J, Sen S, Francis DP, Davies JEet al., 2021, Comparing invasive hemodynamic responses in adenosine hyperemia versus physical exercise stress in chronic coronary syndromes, INTERNATIONAL JOURNAL OF CARDIOLOGY, Vol: 342, Pages: 7-14, ISSN: 0167-5273

Journal article

Rajkumar C, Shun-Shin M, Seligman H, Ahmad Y, Warisawa T, Cook C, Howard J, Ganesananthan S, Amarin L, Khan C, Ahmed A, Nowbar A, Foley M, Assomull R, Keenan N, Sehmi J, Keeble T, davies J, Tang K, Gerber R, Cole G, O'Kane P, Sharp A, Khamis R, Kanaganayagam G, Petraco R, Ruparelia N, Malik I, Nijjer S, Sen S, Francis D, Al-Lamee Ret al., 2021, Placebo-controlled efficacy of percutaneous coronary intervention for focal and diffuse patterns of stable coronary artery disease, Circulation: Cardiovascular Interventions, Vol: 14, Pages: 809-818, ISSN: 1941-7640

Background Physiological assessment with pressure wire pullback can characterize coronary artery disease (CAD) with a focal or diffuse pattern. However, the clinical relevance of this distinction is unknown. We use data from ORBITA to test if the pattern of CAD predicts the placebo-controlled efficacy of percutaneous coronary intervention (PCI) on stress echocardiography ischemia and symptom endpoints.Methods164 patients in ORBITA underwent blinded instantaneous wave-free ratio (iFR) pullback assessment prior to randomization. Focal disease was defined as 0.03 iFR unit drop within 15mm, rather than over a longer distance. Analyses were performed using regression modelling. ResultsIn the PCI arm (n=85), 48 were focal and 37 were diffuse. In the placebo arm (n=79), 35 were focal and 44 were diffuse. Focal stenoses were associated with significantly lower fractional flow reserve (FFR) and iFR values than diffusely diseased vessels (focal mean FFR and iFR 0.600.15 and 0.650.24, diffuse 0.780.10 and 0.880.08 respectively, p<0.0001). With adjustment for this difference, PCI for focal stenoses resulted in significantly greater reduction in stress echo ischemia than PCI for diffuse disease (p<0.05). The effect of PCI on between-arm pre-randomization-adjusted exercise time was 9.32 seconds (95% CI, -17.1 to 35.7s; p=0.487). When stratified for pattern of disease, there was no detectable difference between focal and diffuse CAD (Pinteraction=0.700). PCI improved Seattle Angina Questionnaire angina frequency score and freedom from angina more than placebo (p=0.034; p=0.0035). However, there was no evidence of interaction between the physiological pattern of CAD and these effects (Pinteraction=0.436; Pinteraction=0.908).ConclusionPCI achieved significantly greater reduction of stress echocardiography ischemia in focal compared to diffuse CAD. However, for symptom endpoints, no such difference was observed.

Journal article

Howard J, Francis D, 2021, Machine learning with convolutional neural networks for clinical cardiologists, Heart, ISSN: 1355-6037

Journal article

Patel R, Thong EHE, Batta V, Bharath AA, Francis D, Howard Jet al., 2021, Automated Identification of Orthopedic Implants on Radiographs Using Deep Learning., Radiol Artif Intell, Vol: 3

Accurate identification of metallic orthopedic implant design is important for preoperative planning of revision arthroplasty. Surgical records of implant models are frequently unavailable. The aim of this study was to develop and evaluate a convolutional neural network for identifying orthopedic implant models using radiographs. In this retrospective study, 427 knee and 922 hip unilateral anteroposterior radiographs, including 12 implant models from 650 patients, were collated from an orthopedic center between March 2015 and November 2019 to develop classification networks. A total of 198 images paired with autogenerated image masks were used to develop a U-Net segmentation network to automatically zero-mask around the implants on the radiographs. Classification networks processing original radiographs, and two-channel conjoined original and zero-masked radiographs, were ensembled to provide a consensus prediction. Accuracies of five senior orthopedic specialists assisted by a reference radiographic gallery were compared with network accuracy using McNemar exact test. When evaluated on a balanced unseen dataset of 180 radiographs, the final network achieved a 98.9% accuracy (178 of 180) and 100% top-three accuracy (180 of 180). The network performed superiorly to all five specialists (76.1% [137 of 180] median accuracy and 85.6% [154 of 180] best accuracy; both P < .001), with robustness to scan quality variation and difficult to distinguish implants. A neural network model was developed that outperformed senior orthopedic specialists at identifying implant models on radiographs; real-world application can now be readily realized through training on a broader range of implants and joints, supported by all code and radiographs being made freely available. Supplemental material is available for this article. Keywords: Neural Networks, Skeletal-Appendicular, Knee, Hip, Computer Applications-General (Informatics), Prostheses, Technology Assess-ment, Observer Perform

Journal article

El Hajj SC, Toya T, Warisawa T, Nan J, Lewis BR, Cook CM, Rajkumar C, Howard JP, Seligman H, Ahmad Y, Doi S, Nakajima A, Nakayama M, Goto S, Vera-Urquiza R, Sato T, Kikuta Y, Kawase Y, Nishina H, Nakamura S, Matsuo H, Escaned J, Akashi YJ, Davies JE, Lerman Aet al., 2021, Correlation of Intravascular Ultrasound and Instantaneous Wave-Free Ratio in Patients With Intermediate Left Main Coronary Artery Disease, CIRCULATION-CARDIOVASCULAR INTERVENTIONS, Vol: 14, Pages: 601-608, ISSN: 1941-7640

Journal article

Mann I, Linton NWF, Coyle C, Howard JP, Fudge M, Lim E, Qureshi N, Koa-Wing M, Whinnett Z, Lim PB, Ng FS, Peters NS, Francis DP, Kanagaratnam Pet al., 2021, RETRO-MAPPING A New Approach to Activation Mapping in Persistent Atrial Fibrillation Reveals Evidence of Spatiotemporal Stability, CIRCULATION-ARRHYTHMIA AND ELECTROPHYSIOLOGY, Vol: 14, ISSN: 1941-3149

Journal article

Ahmad Y, Howard J, 2021, Long-term follow-up after ultrathin versus conventional second-generation drug-eluting stents: a systematic review and meta-analysis of randomized controlled trials, European Heart Journal, Vol: 42, Pages: 2643-2654, ISSN: 0195-668X

AimsContemporary 2nd-generation thin-strut drug-eluting stents (DES) are considered standard of care for revascularization of patients undergoing percutaneous coronary intervention. A previous meta-analysis of 10 randomized controlled trials (RCTs) with 11 658 patients demonstrated a 16% reduction in the 1-year risk of target lesion failure (TLF) with ultrathin-strut DES compared with conventional 2nd-generation thin-strut DES. Whether this benefit is sustained longer term is not known, and newer trial data may inform these relative outcomes. We therefore sought to perform an updated systematic review and meta-analysis of RCTs comparing clinical outcomes with ultrathin-strut DES (≤70 µm strut thickness) with conventional 2nd-generation thin-strut DES.Methods and resultsWe performed a random-effects meta-analysis of all RCTs comparing ultrathin-strut DES to conventional 2nd-generation thin-strut DES. The pre-specified primary endpoint was long-term TLF, a composite of cardiac death, myocardial infarction (MI), or clinically driven target lesion revascularization (CD-TLR). Secondary endpoints included the components of TLF, stent thrombosis (ST), and all-cause death. There were 16 eligible trials in which 20 701 patients were randomized. The weighted mean follow-up duration was 2.5 years. Ultrathin-strut DES were associated with a 15% reduction in long-term TLF compared with conventional 2nd-generation thin-strut DES [relative risk (RR) 0.85, 95% confidence interval (CI) 0.76–0.96, P = 0.008] driven by a 25% reduction in CD-TLR (RR 0.75, 95% CI 0.62–0.92, P = 0.005). There were no significant differences between stent types in the risks of MI, ST, cardiac death, or all-cause mortality.ConclusionsAt a mean follow-up of 2.5 years, ultrathin-strut DES reduced the risk of TLF, driven by less CD-TLR compared with conventional 2nd-generation thin-strut DES, with similar risks of MI, ST, cardiac death, and

Journal article

Howard J, Stowell C, Cole G, Ananthan K, Camelia D, Pearce K, Rajani R, Sehmi J, Vimalesvaran K, Kanaganayagam G, McPhail E, Ghosh A, Chambers J, Singh A, Zolgharni M, Rana B, Francis D, Shun-Shin M, Howard J, Stowell C, Cole G, Ananthan K, Demetrescu C, Pearce K, Rajani R, Sehmi J, Vimalesvaran K, Kanaganayagam G, McPhail E, Ghosh A, Chambers J, Singh A, Zolgharni M, Rana B, Francis D, Shun-Shin Met al., 2021, Automated left ventricular dimension assessment using artificial intelligence developed and validated by a UK-wide collaborative, Circulation: Cardiovascular Imaging, Vol: 14, Pages: 405-415, ISSN: 1941-9651

Background: Echocardiography artificial intelligence (AI) requires training and validation to standards expected of humans. We developed an online platform and established the Unity Collaborative to build a dataset of expertise from 17 hospitals for training, validation, and standardisation of such techniques. Methods: The training dataset were 2056individual frames drawn at random from 1265parasternal long-axis video-loops of patients undergoing clinical echocardiography in 2015-2016. Nine experts labelled these images using our online platform. From this, we trained a convolutional neural network to identify key points. Subsequently, 13 experts labelled a validation dataset of the end-systolic and end-diastolic frame from100new video-loops, twice each. The 26-opinionconsensus was used as the reference standard. The primary outcome was “precision SD”, the standard deviation of difference between AI measurement and expert consensus. Results: In the validation dataset, the AI’s precision SD for left ventricular internal dimension was 3.5mm. For context, precision SD of individual expert measurements against the expert consensus was 4.4mm. Intraclass correlation coefficient (ICC) between AI and expert consensus was 0.926 (95% CI 0.904–0.944), compared with 0.817 (0.778–0.954) between individual experts and expert consensus. For interventricular septum thickness, precision SD was 1.8mm for AI (ICC 0.809; 0.729–0.967), versus 2.0 for individuals (ICC 0.641; 0.568–0.716). For posterior wall thickness, precision SD was 1.4mm for AI (ICC 0.535; 95% CI 0.379–0.661), versus 2.2mm for individuals(0.366; 0.288 to 0.462).We present all images and annotations. This highlights challenging cases, including poor image quality, tapered ventricles, and indistinct boundaries. Conclusions: Experts at multiple institutions successfully cooperated to build a collaborative AI. This performed as well as individual experts. Future echocardiogr

Journal article

Azarmehr N, Ye X, Howard JP, Lane ES, Labs R, Shun-Shin MJ, Cole GD, Bidaut L, Francis DP, Zolgharni Met al., 2021, Neural architecture search of echocardiography view classifiers, JOURNAL OF MEDICAL IMAGING, Vol: 8, ISSN: 2329-4302

Journal article

Ahmad Y, Howard J, 2021, Meta-analysis of usefulness of cerebral embolic protection during transcatheter aortic valve implantation, American Journal of Cardiology, Vol: 146, Pages: 69-73, ISSN: 0002-9149

One of the most feared complications of transcatheter aortic valve implantation (TAVI) is stroke, with increased mortality and disability observed in patients suffering a stroke after TAVI. There has been no significant decline in stroke rates seen over the last 5 years; attention has therefore been given to strategies for cerebral embolic protection. With the emergence of new randomized trial data, we sought to perform an updated systematic review and meta-analysis to examine the effect of cerebral embolic protection during TAVI both on clinical outcomes and on neuroimaging parameters. We performed a random-effects meta-analysis of randomized clinical trials of cerebral embolic protection during TAVI. The primary end point was the risk of stroke. The risk of stroke was not significantly different with the use of cerebral embolic protection: relative risk (RR) 0.88, 95% confidence interval (CI) 0.57 to 1.36, p = 0.566. Nor was there a significant reduction in the risk of disabling stroke, non-disabling stroke or death. There was no significant difference in total lesion volume on MRI with cerebral embolic protection: mean difference -74.94, 95% CI -174.31 to 24.4, p = 0.139. There was also not a significant difference in the number of new ischemic lesions on MRI: mean difference -2.15, 95% -5.25 to 0.96, p = 0.176, although there was significant heterogeneity for the neuroimaging outcomes. In conclusion, cerebral embolic protection during TAVI is safe but there is no evidence of a statistically significant benefit on clinical outcomes or neuroimaging parameters.

Journal article

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