Imperial College London

ProfessorDarrelFrancis

Faculty of MedicineNational Heart & Lung Institute

Professor of Cardiology
 
 
 
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Contact

 

+44 (0)20 7594 3381d.francis Website

 
 
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Assistant

 

Miss Juliet Holmes +44 (0)20 7594 5735

 
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Location

 

Block B Hammersmith HospitalHammersmith Campus

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Summary

 

Publications

Publication Type
Year
to

621 results found

Wood FA, Howard JP, Finegold JA, Nowbar AN, Thompson DM, Arnold AD, Rajkumar CA, Connolly S, Cegla J, Stride C, Sever P, Norton C, Thom SAM, Shun-Shin MJ, Francis DPet al., 2020, N-of-1 trial of a statin, placebo, or No treatment to assess side effects., New England Journal of Medicine, ISSN: 0028-4793

Journal article

Howard JP, Zaman S, Ragavan A, Hall K, Leonard G, Sutanto S, Ramadoss V, Razvi Y, Linton NF, Bharath A, Shun-Shin M, Rueckert D, Francis D, Cole Get al., 2020, Automated analysis and detection of abnormalities in transaxial anatomical cardiovascular magnetic resonance images: a proof of concept study with potential to optimize image acquisition., Int J Cardiovasc Imaging

The large number of available MRI sequences means patients cannot realistically undergo them all, so the range of sequences to be acquired during a scan are protocolled based on clinical details. Adapting this to unexpected findings identified early on in the scan requires experience and vigilance. We investigated whether deep learning of the images acquired in the first few minutes of a scan could provide an automated early alert of abnormal features. Anatomy sequences from 375 CMR scans were used as a training set. From these, we annotated 1500 individual slices and used these to train a convolutional neural network to perform automatic segmentation of the cardiac chambers, great vessels and any pleural effusions. 200 scans were used as a testing set. The system then assembled a 3D model of the thorax from which it made clinical measurements to identify important abnormalities. The system was successful in segmenting the anatomy slices (Dice 0.910) and identified multiple features which may guide further image acquisition. Diagnostic accuracy was 90.5% and 85.5% for left and right ventricular dilatation, 85% for left ventricular hypertrophy and 94.4% for ascending aorta dilatation. The area under ROC curve for diagnosing pleural effusions was 0.91. We present proof-of-concept that a neural network can segment and derive accurate clinical measurements from a 3D model of the thorax made from transaxial anatomy images acquired in the first few minutes of a scan. This early information could lead to dynamic adaptive scanning protocols, and by focusing scanner time appropriately and prioritizing cases for supervision and early reporting, improve patient experience and efficiency.

Journal article

Leong KMW, Ng FS, Shun-Shin MJ, Koa-Wing M, Qureshi N, Whinnett ZI, Linton NF, Lefroy D, Francis DP, Harding SE, Davies DW, Peter NS, Lim PB, Behr E, Lambiase PD, Varnava A, Kanagaratnam Pet al., 2020, Non-invasive detection of exercise-induced cardiac conduction abnormalities in sudden cardiac death survivors in the inherited cardiac conditions., Europace

AIMS : Rate adaptation of the action potential ensures spatial heterogeneities in conduction across the myocardium are minimized at different heart rates providing a protective mechanism against ventricular fibrillation (VF) and sudden cardiac death (SCD), which can be quantified by the ventricular conduction stability (V-CoS) test previously described. We tested the hypothesis that patients with a history of aborted SCD due to an underlying channelopathy or cardiomyopathy have a reduced capacity to maintain uniform activation following exercise. METHODS AND RESULTS : Sixty individuals, with (n = 28) and without (n = 32) previous aborted-SCD event underwent electro-cardiographic imaging recordings following exercise treadmill test. These included 25 Brugada syndrome, 13 hypertrophic cardiomyopathy, 12 idiopathic VF, and 10 healthy controls. Data were inputted into the V-CoS programme to calculate a V-CoS score that indicate the percentage of ventricle that showed no significant change in ventricular activation, with a lower score indicating the development of greater conduction heterogeneity. The SCD group, compared to those without, had a lower median (interquartile range) V-CoS score at peak exertion [92.8% (89.8-96.3%) vs. 97.3% (94.9-99.1%); P < 0.01] and 2 min into recovery [95.2% (91.1-97.2%) vs. 98.9% (96.9-99.5%); P < 0.01]. No significant difference was observable later into recovery at 5 or 10 min. Using the lowest median V-CoS scores obtained during the entire recovery period post-exertion, SCD survivors had a significantly lower score than those without for each of the different underlying aetiologies. CONCLUSION : Data from this pilot study demonstrate the potential use of this technique in risk stratification for the inherited cardiac conditions.

Journal article

Cunniffe NG, Gunter SJ, Brown M, Burge SW, Coyle C, De Soyza A, Dymond T, Esmail H, Francis DP, Galloway J, Galloway JB, Gkrania-Klotsas E, Greenaway J, Katritsis G, Kanagaratnam P, Knolle MD, Leonard K, McIntyre ZC, Prudon B, Rampling T, Torok ME, Warne B, Yates M, Matheson NJ, Su L, Villar S, Stewart GD, Toshner Met al., 2020, How achievable are COVID-19 clinical trial recruitment targets? A UK observational cohort study and trials registry analysis., BMJ Open, Vol: 10

OBJECTIVES: To analyse enrolment to interventional trials during the first wave of the COVID-19 pandemic in England and describe the barriers to successful recruitment in the circumstance of a further wave or future pandemics. DESIGN: We analysed registered interventional COVID-19 trial data and concurrently did a prospective observational study of hospitalised patients with COVID-19 who were being assessed for eligibility to one of the RECOVERY, C19-ACS or SIMPLE trials. SETTING: Interventional COVID-19 trial data were analysed from the clinicaltrials.gov and International Standard Randomized Controlled Trial Number databases on 12 July 2020. The patient cohort was taken from five centres in a respiratory National Institute for Health Research network. Population and modelling data were taken from published reports from the UK government and Medical Research Council Biostatistics Unit. PARTICIPANTS: 2082 consecutive admitted patients with laboratory-confirmed SARS-CoV-2 infection from 27 March 2020 were included. MAIN OUTCOME MEASURES: Proportions enrolled, and reasons for exclusion from the aforementioned trials. Comparisons of trial recruitment targets with estimated feasible recruitment numbers. RESULTS: Analysis of trial registration data for COVID-19 treatment studies enrolling in England showed that by 12 July 2020, 29 142 participants were needed. In the observational study, 430 (20.7%) proceeded to randomisation. 82 (3.9%) declined participation, 699 (33.6%) were excluded on clinical grounds, 363 (17.4%) were medically fit for discharge and 153 (7.3%) were receiving palliative care. With 111 037 people hospitalised with COVID-19 in England by 12 July 2020, we determine that 22 985 people were potentially suitable for trial enrolment. We estimate a UK hospitalisation rate of 2.38%, and that another 1.25 million infections would be required to meet recruitment targets of ongoing trials. CONCLUSIONS: Feasible recruitment rates, study desig

Journal article

Keene D, Shun-Shin MJ, Arnold AD, March K, Qureshi N, Ng FS, Tanner M, Linton N, Lim PB, Lefroy D, Kanagaratnam P, Peters NS, Francis DP, Whinnett ZIet al., 2020, Within-patient comparison of His-bundle pacing, right ventricular pacing, and right ventricular pacing avoidance algorithms in patients with PR prolongation: Acute hemodynamic study, JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, ISSN: 1045-3873

Journal article

Ahmad Y, Howard JP, Arnold AD, Ali ZD, Francis D, Moses JW, Leon MB, Kirtane AJ, Karmpaliotis D, Stone GWet al., 2020, Drug-eluting stents versus bypass surgery for left main disease: an updated meta-analysis of randomized controlled trials with long-term follow-up, American Journal of Cardiology, Vol: 132, Pages: 168-172, ISSN: 0002-9149

Journal article

Ahmad Y, 2020, Mortality after drug-eluting stents versus coronary artery bypass grafting for left main coronary artery disease: A meta-analysis of randomized controlled trials, European Heart Journal, Vol: 41, Pages: 3228-3235, ISSN: 0195-668X

Aims The optimal method of revascularization for patients with left main coronary artery disease (LMCAD) is controversial. Coronary artery bypass graft surgery (CABG) has traditionally been considered the gold standard therapy, and recent randomized trials comparing CABG with percutaneous coronary intervention (PCI) with drug-eluting stents (DES) have reported conflicting outcomes. We, therefore, performed a systematic review and updated meta-analysis comparing CABG to PCI with DES for the treatment of LMCAD.Methods and results We systematically identified all randomized trials comparing PCI with DES vs. CABG in patients with LMCAD. The primary efficacy endpoint was all-cause mortality. Secondary endpoints included cardiac death, myocardial infarction (MI), stroke, and unplanned revascularization. All analyses were by intention-to-treat. There were five eligible trials in which 4612 patients were randomized. The weighted mean follow-up duration was 67.1 months. There were no significant differences between PCI and CABG for the risk of all-cause mortality [relative risk (RR) 1.03, 95% confidence interval (CI) 0.81–1.32; P = 0.779] or cardiac death (RR 1.03, 95% CI 0.79–1.34; P = 0.817). There were also no significant differences in the risk of stroke (RR 0.74, 95% CI 0.35–1.50; P = 0.400) or MI (RR 1.22, 95% CI 0.96–1.56; P = 0.110). Percutaneous coronary intervention was associated with an increased risk of unplanned revascularization (RR 1.73, 95% CI 1.49–2.02; P < 0.001).Conclusion The totality of randomized clinical trial evidence demonstrated similar long-term mortality after PCI with DES compared with CABG in patients with LMCAD. Nor were there significant differences in cardiac death, stroke, or MI between PCI and CABG. Unplanned revascularization procedures were less common after CABG compared with PCI. These findings may inform clinica

Journal article

Kaura A, Sterne J, Trickey A, Abbott S, Mulla A, Glampson B, Panoulas V, Davies J, Woods K, Omigie J, Shah A, Channon K, Weber J, Thursz M, Elliott P, Hemingway H, Williams B, Asselbergs F, OSullivan M, Lord G, Melikian N, Johnson T, Francis D, Shah A, Perera D, Kharbanda R, Patel R, Mayet Jet al., 2020, Invasive versus non-invasive management of elderly patients with non-ST elevation myocardial infarction: cohort study based on routine clinical data, The Lancet, Vol: 396, Pages: 623-634, ISSN: 0140-6736

BackgroundPrevious trials suggest lower long-term mortality after invasive rather than non-invasive management among patients with non-ST elevation myocardial infarction (NSTEMI), but these excluded very elderly patients.MethodsWe estimated the effect of invasive versus non-invasive management within 3 days of peak troponin on survival in NSTEMI patients aged ≥80 years, using routine clinical data collected during 2010–2017 (NIHR Health Informatics Collaborative). Propensity scores based on pre-treatment variables were derived using logistic regression; patients with high probabilities of non-invasive or invasive management were excluded. Patients who died within 3 days without receiving invasive management were assigned to the invasive or non-invasive management groups based on their propensity scores, to mitigate immortal time bias. We estimated mortality hazard ratios comparing invasive with non-invasive management, and also compared rates of hospital admission for heart failure.FindingsOf 1976 patients with NSTEMI, 101 died within 3 days of their peak troponin, whilst 375 were excluded because of extreme propensity scores. The remaining 1500 patients (56% non-invasive management) had a median age 86 (IQR 82-89) years. During median follow-up of 3.0 (IQR 1.2-4.8) years, there were 613 (41%) deaths. Using inverse probability weighting, adjusted cumulative 5-year mortality was 36% and 55% in the invasive and non-invasive management groups, respectively. The mortality hazard ratio comparing invasive with non-invasive management was 0.64 (95% CI 0.52-0.79) after multivariable adjustment for clinical characteristics and propensity score and inclusion of patients who died within three days. Invasive management was associated with lower incidence of hospital admissions for heart failure (adjusted rate ratio compared with non-invasive management 0.67, 95% CI 0.48–0.93).

Journal article

Haldar S, Khan HR, Boyalla V, Kralj-Hans I, Jones S, Lord J, Onyimadu O, Satishkumar A, Bahrami T, De Souza A, Clague JR, Francis DP, Hussain W, Jarman JW, Jones DG, Chen Z, Mediratta N, Hyde J, Lewis M, Mohiaddin R, Salukhe TV, Murphy C, Kelly J, Khattar RS, Toff WD, Markides V, McCready J, Gupta D, Wong T, CASA-AF Investigatorset al., 2020, Catheter ablation vs. thoracoscopic surgical ablation in long-standing persistent atrial fibrillation: CASA-AF randomized controlled trial., European Heart Journal, ISSN: 0195-668X

AIMS: Long-standing persistent atrial fibrillation (LSPAF) is challenging to treat with suboptimal catheter ablation (CA) outcomes. Thoracoscopic surgical ablation (SA) has shown promising efficacy in atrial fibrillation (AF). This multicentre randomized controlled trial tested whether SA was superior to CA as the first interventional strategy in de novo LSPAF. METHODS AND RESULTS: We randomized 120 LSPAF patients to SA or CA. All patients underwent predetermined lesion sets and implantable loop recorder insertion. Primary outcome was single procedure freedom from AF/atrial tachycardia (AT) ≥30 s without anti-arrhythmic drugs at 12 months. Secondary outcomes included clinical success (≥75% reduction in AF/AT burden); procedure-related serious adverse events; changes in patients' symptoms and quality-of-life scores; and cost-effectiveness. At 12 months, freedom from AF/AT was recorded in 26% (14/54) of patients in SA vs. 28% (17/60) in the CA group [OR 1.128, 95% CI (0.46-2.83), P = 0.83]. Reduction in AF/AT burden ≥75% was recorded in 67% (36/54) vs. 77% (46/60) [OR 1.13, 95% CI (0.67-4.08), P = 0.3] in SA and CA groups, respectively. Procedure-related serious adverse events within 30 days of intervention were reported in 15% (8/55) of patients in SA vs. 10% (6/60) in CA, P = 0.46. One death was reported after SA. Improvements in AF symptoms were greater following CA. Over 12 months, SA was more expensive and provided fewer quality-adjusted life-years (QALYs) compared with CA (0.78 vs. 0.85, P = 0.02). CONCLUSION: Single procedure thoracoscopic SA is not superior to CA in treating LSPAF. Catheter ablation provided greater improvements in symptoms and accrued significantly more QALYs during follow-up than SA. CLINICAL TRIAL REGISTRATION: ISRCTN18250790 and ClinicalTrials.gov: NCT02755688.

Journal article

Arnold AD, Howard JP, Gopi AA, Chan CP, Ali N, Keene D, Shun-Shin MJ, Ahmad Y, Wright IJ, Ng FS, Linton NWF, Kanagaratnam P, Peters NS, Rueckert D, Francis DP, Whinnett ZIet al., 2020, Discriminating electrocardiographic responses to His-bundle pacing using machine learning., Cardiovascular Digital Health Journal, Vol: 1, Pages: 11-20

Background: His-bundle pacing (HBP) has emerged as an alternative to conventional ventricular pacing because of its ability to deliver physiological ventricular activation. Pacing at the His bundle produces different electrocardiographic (ECG) responses: selective His-bundle pacing (S-HBP), non-selective His bundle pacing (NS-HBP), and myocardium-only capture (MOC). These 3 capture types must be distinguished from each other, which can be challenging and time-consuming even for experts. Objective: The purpose of this study was to use artificial intelligence (AI) in the form of supervised machine learning using a convolutional neural network (CNN) to automate HBP ECG interpretation. Methods: We identified patients who had undergone HBP and extracted raw 12-lead ECG data during S-HBP, NS-HBP, and MOC. A CNN was trained, using 3-fold cross-validation, on 75% of the segmented QRS complexes labeled with their capture type. The remaining 25% was kept aside as a testing dataset. Results: The CNN was trained with 1297 QRS complexes from 59 patients. Cohen kappa for the neural network's performance on the 17-patient testing set was 0.59 (95% confidence interval 0.30 to 0.88; P <.0001), with an overall accuracy of 75%. The CNN's accuracy in the 17-patient testing set was 67% for S-HBP, 71% for NS-HBP, and 84% for MOC. Conclusion: We demonstrated proof of concept that a neural network can be trained to automate discrimination between HBP ECG responses. When a larger dataset is trained to higher accuracy, automated AI ECG analysis could facilitate HBP implantation and follow-up and prevent complications resulting from incorrect HBP ECG analysis.

Journal article

Warisawa T, Howard JP, Kawase Y, Tanigaki T, Omori H, Cook CM, Ahmad Y, Francis DP, Akashi YJ, Matsuo H, Davies JEet al., 2020, Difference in functional assessment of individual stenosis severity in serial coronary lesions between resting and hyperemic pressure-wire pullback: Insights from the GIFT registry, INTERNATIONAL JOURNAL OF CARDIOLOGY, Vol: 312, Pages: 10-15, ISSN: 0167-5273

Journal article

Marquis-Gravel G, Moliterno DJ, Francis DP, Juni P, Rosenberg YD, Claessen BE, Mentz RJ, Mehran R, Cutlip DE, Chauhan C, Quella S, Zannad F, Goodman SGet al., 2020, Improving the Design of Future PCI Trials for Stable Coronary Artery Disease JACC State-of-the-Art Review, JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY, Vol: 76, Pages: 435-450, ISSN: 0735-1097

Journal article

Warisawa T, Cook CM, Rajkumar C, Howard JP, Seligman H, Ahmad Y, El Hajj S, Doi S, Nakajima A, Nakayama M, Goto S, Vera-Urquiza R, Sato T, Kikuta Y, Kawase Y, Nishina H, Petraco R, Al-Lamee R, Nijjer S, Sen S, Nakamura S, Lerman A, Matsuo H, Francis DP, Akashi YJ, Escaned J, Davies JEet al., 2020, Safety of Revascularization Deferral of Left Main Stenosis Based on Instantaneous Wave-Free Ratio Evaluation, JACC-CARDIOVASCULAR INTERVENTIONS, Vol: 13, Pages: 1655-1664, ISSN: 1936-8798

Journal article

Piepoli MF, Ponikowski PP, Volterrani M, Francis DP, Coats AJSet al., 2020, DoCheyne andStokes have an important message for modern-day patients with heart failure?Yes, they do, EUROPEAN JOURNAL OF HEART FAILURE, ISSN: 1388-9842

Journal article

Ahmad Y, 2020, Complete revascularisation by percutaneous coronary intervention for patients with ST-segment elevation myocardial infarction and multivessel coronary artery disease: an updated meta-analysis and meta-regression of randomized trials, Journal of the American Heart Association, Vol: 9, Pages: 1-83, ISSN: 2047-9980

BackgroundFor patients with ST‐segment–elevation myocardial infarction (STEMI) and multivessel coronary artery disease, the optimal treatment of the non‐infarct‐related artery has been controversial. This up‐to‐date meta‐analysis focusing on individual clinical end points was performed to further evaluate the benefit of complete revascularization with percutaneous coronary intervention for patients with STEMI and multivessel coronary artery disease.Methods and ResultsWe systematically identified all randomized trials comparing complete revascularization with percutaneous coronary intervention to culprit‐only revascularization for multivessel disease in STEMI and performed a random‐effects meta‐analysis. The primary efficacy end point was cardiovascular death analyzed on an intention‐to‐treat basis. Secondary end points included all‐cause mortality, myocardial infarction, and unplanned revascularization. Ten studies (7542 patients) were included: 3664 patients were randomized to complete revascularization and 3878 to culprit‐only revascularization. Across all patients, complete revascularization was superior to culprit‐only revascularization for reduction in the risk of cardiovascular death (relative risk [RR], 0.68; 95% CI, 0.47–0.98; P=0.037; I2=21.8%) and reduction in the risk of myocardial infarction (RR, 0.65; 95% CI, 0.54–0.79; P<0.0001; I2=0.0%). Complete revascularization also significantly reduced the risk of unplanned revascularization (RR, 0.37; 95% CI, 0.28–0.51; P<0.0001; I2=64.7%). The difference in all‐cause mortality with percutaneous coronary intervention was not statistically significant (RR, 0.85; 95% CI, 0.69–1.04; P=0.108; I2=0.0%).ConclusionsFor patients with STEMI and multivessel disease, complete revascularization with percutaneous coronary intervention significantly improves hard clinical outcomes including cardiovascular death and myocardial infarction. These data have implications for clinical practice gu

Journal article

Ziff OJ, Samra M, Howard JP, Bromage DI, Ruschitzka F, Francis DP, Kotecha Det al., 2020, Beta-blocker efficacy across different cardiovascular indications: an umbrella review and meta-analytic assessment, BMC MEDICINE, Vol: 18, ISSN: 1741-7015

Journal article

Kaura A, Arnold AD, Vasileios P, Glampson B, Davies J, Mulla A, Woods K, Omigie J, Shah AD, Channon KM, Weber JN, Thursz MR, Elliott P, Hemingway H, Williams B, Asselbergs FW, OSullivan M, Lord GM, Melikian N, Lefroy DC, Francis DP, Shah AM, Kharbanda R, Perera D, Patel RS, Mayet Jet al., 2020, Prognostic significance of troponin level in 3,121 patients presenting with atrial fibrillation (The NIHR Health Informatics Collaborative TROP-AF study), Journal of the American Heart Association, Vol: 9, ISSN: 2047-9980

Background-—Patients presenting with atrial fibrillation (AF) often undergo a blood test to measure troponin, but interpretation of theresult is impeded by uncertainty about its clinical importance. We investigated the relationship between troponin level, coronaryangiography, and all-cause mortality in real-world patients presenting with AF.Methods and Results-—We used National Institute of Health Research Health Informatics Collaborative data to identify patients admitted between 2010 and 2017 at 5 tertiary centers in the United Kingdom with a primary diagnosis of AF. Peak troponin results 7 were scaled as multiples of the upper limit of normal. A total of 3121 patients were included in the analysis. Over a median followup of 1462 (interquartile range, 929–1975) days, there were 586 deaths (18.8%). The adjusted hazard ratio for mortality associatedwith a positive troponin (value above upper limit of normal) was 1.20 (95% CI, 1.01–1.43; P<0.05). Higher troponin levels were associated with higher risk of mortality, reaching a maximum hazard ratio of 2.6 (95% CI, 1.9–3.4) at 250 multiples of the upper limit of normal. There was an exponential relationship between higher troponin levels and increased odds of coronary angiography.The mortality risk was 36% lower in patients undergoing coronary angiography than in those who did not (adjusted hazard ratio, 0.61; 95% CI, 0.42–0.89; P=0.01).Conclusions-—Increased troponin was associated with increased risk of mortality in patients presenting with AF. The lower hazard ratio in patients undergoing invasive management raises the possibility that the clinical importance of troponin release in AF may be mediated by coronary artery disease, which may be responsive to revascularization.

Journal article

Azarmehr N, Ye X, Howes JD, Docking B, Howard JP, Francis DP, Zolgharni Met al., 2020, An optimisation-based iterative approach for speckle tracking echocardiography, MEDICAL & BIOLOGICAL ENGINEERING & COMPUTING, Vol: 58, Pages: 1309-1323, ISSN: 0140-0118

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 GV, Mohdnazri S, Gamma R, de Waard GA, Al-Lamee R, Keeble TR, Mayet J, Sen S, Francis DP, Davies JEet al., 2020, How Do Fractional Flow Reserve, Whole-Cycle PdPa, and Instantaneous Wave-Free Ratio Correlate With Exercise Coronary Flow Velocity During Exercise-Induced Angina?, CIRCULATION-CARDIOVASCULAR INTERVENTIONS, Vol: 13, ISSN: 1941-7640

Journal article

Howard JP, Tan J, Shun-Shin MJ, Mahdi D, Nowbar AN, Arnold AD, Ahmad Y, McCartney P, Zolgharni M, Linton NWF, Sutaria N, Rana B, Mayet J, Rueckert D, Cole GD, Francis DPet al., 2020, Improving ultrasound video classification: an evaluation of novel deep learning methods in echocardiography., J Med Artif Intell, Vol: 3

Echocardiography is the commonest medical ultrasound examination, but automated interpretation is challenging and hinges on correct recognition of the 'view' (imaging plane and orientation). Current state-of-the-art methods for identifying the view computationally involve 2-dimensional convolutional neural networks (CNNs), but these merely classify individual frames of a video in isolation, and ignore information describing the movement of structures throughout the cardiac cycle. Here we explore the efficacy of novel CNN architectures, including time-distributed networks and two-stream networks, which are inspired by advances in human action recognition. We demonstrate that these new architectures more than halve the error rate of traditional CNNs from 8.1% to 3.9%. These advances in accuracy may be due to these networks' ability to track the movement of specific structures such as heart valves throughout the cardiac cycle. Finally, we show the accuracies of these new state-of-the-art networks are approaching expert agreement (3.6% discordance), with a similar pattern of discordance between views.

Journal article

Bachtiger P, Plymen CM, Pabari PA, Howard JP, Whinnett ZI, Opoku F, Janering S, Faisal AA, Francis DP, Peters NSet al., 2020, Artificial intelligence, data sensors and interconnectivity: future Opportunities for heart failure, Cardiac Failure Review, Vol: 6, Pages: e11-e11, ISSN: 2057-7540

A higher proportion of patients with heart failure have benefitted from a wide and expanding variety of sensor-enabled implantable devices than any other patient group. These patients can now also take advantage of the ever-increasing availability and affordability of consumer electronics. Wearable, on- and near-body sensor technologies, much like implantable devices, generate massive amounts of data. The connectivity of all these devices has created opportunities for pooling data from multiple sensors - so-called interconnectivity - and for artificial intelligence to provide new diagnostic, triage, risk-stratification and disease management insights for the delivery of better, more personalised and cost-effective healthcare. Artificial intelligence is also bringing important and previously inaccessible insights from our conventional cardiac investigations. The aim of this article is to review the convergence of artificial intelligence, sensor technologies and interconnectivity and the way in which this combination is set to change the care of patients with heart failure.

Journal article

Chacko L, P Howard J, Rajkumar C, Nowbar AN, Kane C, Mahdi D, Foley M, Shun-Shin M, Cole G, Sen S, Al-Lamee R, Francis DP, Ahmad Yet al., 2020, Effects of percutaneous coronary intervention on death and myocardial infarction stratified by stable and unstable coronary artery disease: a meta-analysis of randomized controlled trials, Circulation: Cardiovascular Quality and Outcomes, Vol: 13, ISSN: 1941-7705

Background:In patients presenting with ST-segment–elevation myocardial infarction, percutaneous coronary intervention (PCI) reduces mortality when compared with fibrinolysis. In other forms of coronary artery disease (CAD), however, it has been controversial whether PCI reduces mortality. In this meta-analysis, we examine the benefits of PCI in (1) patients post–myocardial infarction (MI) who did not receive immediate revascularization; (2) patients who have undergone primary PCI for ST-segment–elevation myocardial infarction but have residual coronary lesions; (3) patients who have suffered a non–ST-segment–elevation acute coronary syndrome; and (4) patients with truly stable CAD with no recent infarct. This analysis includes data from the recently presented International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) and Complete versus Culprit-Only Revascularization Strategies to Treat Multivessel Disease after Early PCI for STEMI (COMPLETE) trials.Methods and Results:We systematically identified all randomized trials of PCI on a background of medical therapy for the treatment of CAD. The ISCHEMIA trial, presented in November 2019, was eligible for inclusion. Data were combined using a random-effects meta-analysis. The primary end point was all-cause mortality. Forty-six trials, including 37 757 patients, were eligible. In the 3 unstable scenarios, PCI had the following effects on mortality: unrevascularized post-MI relative risk (RR) 0.68 (95% CI, 0.45–1.03); P=0.07; multivessel disease following ST-segment–elevation myocardial infarction (RR, 0.84 [95% CI, 0.69–1.04]; P=0.11); non–ST-segment–elevation acute coronary syndrome (RR, 0.84 [95% CI, 0.72–0.97]; P=0.02). Overall, in these unstable scenarios PCI was associated with a significant reduction in mortality (RR, 0.84 [95% CI, 0.75–0.93]; P=0.02). In unstable CAD, PCI also reduced cardiac

Journal article

Azarmehr N, Ye X, Sacchi S, Howard JP, Francis DP, Zolgharni Met al., 2020, Segmentation of Left Ventricle in 2D Echocardiography Using Deep Learning, Pages: 497-504, ISBN: 9783030393427

© 2020, Springer Nature Switzerland AG. The segmentation of Left Ventricle (LV) is currently carried out manually by the experts, and the automation of this process has proved challenging due to the presence of speckle noise and the inherently poor quality of the ultrasound images. This study aims to evaluate the performance of different state-of-the-art Convolutional Neural Network (CNN) segmentation models to segment the LV endocardium in echocardiography images automatically. Those adopted methods include U-Net, SegNet, and fully convolutional DenseNets (FC-DenseNet). The prediction outputs of the models are used to assess the performance of the CNN models by comparing the automated results against the expert annotations (as the gold standard). Results reveal that the U-Net model outperforms other models by achieving an average Dice coefficient of 0.93 ± 0.04, and Hausdorff distance of 4.52 ± 0.90.

Book chapter

Al-lamee RK, Shun-Shin M, Howard J, Nowbar A, Rajkumar C, Thompson D, Sen S, Nijjer S, Petraco R, Davies J, Keeble T, Tang K, Malik I, Bual N, Cook C, Ahmad Y, Seligman H, Sharp A, Talwar S, Assomull R, Cole G, Keenan NG, Kanaganayagam GS, Sehmi JS, Wensel R, Harrell F, Mayet J, Thom S, Davies JE, Francis Det al., 2019, Dobutamine Stress Echocardiography Ischaemia as a Predictor of the Placebo-Controlled Efficacy of Percutaneous Coronary Intervention in Stable Coronary Artery Disease: The Stress Echo-Stratified Analysis of ORBITA, Resuscitation Science Symposium (ReSS), Publisher: LIPPINCOTT WILLIAMS & WILKINS, Pages: E985-E985, ISSN: 0009-7322

Conference paper

Giannoni A, Gentile F, Navari A, Borrelli C, Mirizzi G, Catapano G, Vergaro G, Grotti F, Betta M, Piepoli MF, Francis DP, Passino C, Emdin Met al., 2019, Contribution of the lung to the genesis of cheyne-stokes respiration in heart failure: plant gain beyond chemoreflex gain and circulation time, 80th SIC National Congress, Publisher: OXFORD UNIV PRESS, Pages: J130-J130, ISSN: 1520-765X

Conference paper

Seligman H, Teixeira-Pinto A, Nowbar A, Francis Det al., 2019, Fragility of the Bond Between Cardiovascular Investigators and Their Readers, CIRCULATION-CARDIOVASCULAR QUALITY AND OUTCOMES, Vol: 12, ISSN: 1941-7705

Journal article

Gitto M, Gentile F, Nowbar AN, Shun-Shin M, Seligman H, Rajkumar C, Howard J, Francis D, Chieffo A, Camici PG, Al-lamee Ret al., 2019, Gender-related differences in clinical presentation and angiographic findings in patients with ischaemia and no obstructive coronary artery disease (INOCA): a single-center observational registry, 80th SIC National Congress, Publisher: OXFORD UNIV PRESS, Pages: J157-J157, ISSN: 1520-765X

Conference paper

Ahmad Y, Vendrik J, Eftekhari A, Howard J, Cook C, Rajkumar C, Malik I, Mikhail G, Ruparelia N, Hadjiloizou N, Nijjer S, Al-Lamee R, Petraco R, Warisawa T, Wijntjens GWM, Koch KT, van de Hoef T, de Waard G, Echavarria-Pinto M, Frame A, Sutaria N, Kanaganayagam G, Ariff B, Anderson J, Chukwuemeka A, Fertleman M, Koul S, Iglesias JF, Francis D, Mayet J, Serruys P, Davies J, Escaned J, van Royen N, Götberg M, Terkelsen CJ, Christiansen CH, Piek JJ, Baan Jr J, Sen Set al., 2019, Determining the Predominant Lesion in Patients With Severe Aortic Stenosis and Coronary Stenoses: A Multicenter Study Using Intracoronary Pressure and Flow, Circulation: Cardiovascular Interventions, Vol: 12, ISSN: 1941-7640

Background:Patients with severe aortic stenosis (AS) often have coronary artery disease. Both the aortic valve and the coronary disease influence the blood flow to the myocardium and its ability to respond to stress; leading to exertional symptoms. In this study, we aim to quantify the effect of severe AS on the coronary microcirculation and determine if this is influenced by any concomitant coronary disease. We then compare this to the effect of coronary stenoses on the coronary microcirculation.Methods:Group 1: 55 patients with severe AS and intermediate coronary stenoses treated with transcatheter aortic valve implantation (TAVI) were included. Group 2: 85 patients with intermediate coronary stenoses and no AS treated with percutaneous coronary intervention were included. Coronary pressure and flow were measured at rest and during hyperemia in both groups, before and after TAVI (group 1) and before and after percutaneous coronary intervention (group 2).Results:Microvascular resistance over the wave-free period of diastole increased significantly post-TAVI (pre-TAVI, 2.71±1.4 mm Hg·cm·s−1 versus post-TAVI 3.04±1.6 mm Hg·cm·s−1 [P=0.03]). Microvascular reserve over the wave-free period of diastole significantly improved post-TAVI (pre-TAVI 1.88±1.0 versus post-TAVI 2.09±0.8 [P=0.003]); this was independent of the severity of the underlying coronary stenosis. The change in microvascular resistance post-TAVI was equivalent to that produced by stenting a coronary lesion with an instantaneous wave-free ratio of ≤0.74.Conclusions:TAVI improves microcirculatory function regardless of the severity of underlying coronary disease. TAVI for severe AS produces a coronary hemodynamic improvement equivalent to the hemodynamic benefit of stenting coronary stenoses with instantaneous wave-free ratio values <0.74. Future trials of physiology-guided revascularization in severe AS may consider us

Journal article

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