Samer Alabed

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Verified

Samer verified their affiliation via an institutional email.

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• MD FRCR PhD
• Consultant Cardio Radiologist and Senior Clinical Research Fellow at The University of Sheffield

Objectives This meta-analysis evaluates assessment of pulmonary arterial hypertension (PAH), with a focus on clinical worsening and mortality. Background Cardiac magnetic resonance (CMR) has prognostic value in the assessment of patients with PAH. However, there are limited data on the prediction of clinical worsening, an important composite endpo...

Accurate and efficient quantification of cardiac function is essential for the estimation of prognosis of cardiovascular diseases (CVDs). One of the most commonly used metrics for evaluating cardiac pumping performance is left ventricular ejection fraction (LVEF). However, LVEF can be affected by factors such as inter-observer variability and varyi...

Aims Four-dimensional flow cardiovascular MRI (4D flow CMR) has emerged as a promising technique for assessing aortic stenosis (AS). This study aimed to evaluate the agreement between 4D flow CMR and transthoracic echocardiography (TTE) in estimating peak aortic valve (AV) velocities (V Peak ), grading AS severity and predicting AV intervention in...

Aims Cardiac ageing involves a series of anatomical and physiological changes contributing to a decline in overall performance. Cardiac magnetic resonance (CMR) provides comprehensive structural and functional assessment for detecting age-related cardiovascular remodelling. We aimed to develop a fully automated CMR model to predict functional heart...

Background/Aims There are few published data on outcomes of patients with pulmonary hypertension (PH) associated with anti-synthetase syndrome (ASS). We therefore interrogated a large PH registry to assess patient characteristics and outcomes. Methods Patients assessed for ASS-associated PH were identified from the ASPIRE (Assessing the Spectrum o...

Objective Unenhanced chest computed tomography (CT) is widely used to assess lung malignancies and parenchymal diseases. Harnessing CT data to quantify cardiac and vascular structures has the potential to improve the diagnosis of heart failure and pulmonary hypertension (PH). This study aims to develop an automated deep learning model for segmentat...

Objectives This systematic review aims to critically appraise the performance and quality of deep learning (DL) tools for cardiac structure segmentation on CT. Methods Embase and Medline databases were searched for peer-reviewed studies from January 1, 2013 to December 4, 2023. Studies of supervised DL-based tools for the segmentation of cardiac s...

Purpose This study aimed to evaluate the newly established cardiac sarcoid PET-CT service in a tertiary centre and provide an overview of scanning volume, outcomes, and referral pathways during its first year of operation (January 2024 – January 2025). It also sought to ascertain if there was concordance between regions of abnormality seen on posit...

Background Cardiac CT angiography (CTCA) is increasingly recognised as a crucial investigation for coronary artery disease, but concerns regarding radiation exposure persist. This audit aimed to assess trends in radiation dose over a ten-year period at Sheffield Teaching Hospitals, relating these findings to changes in scanning technology and throu...

Pulmonary hypertension (PH) is frequently underdiagnosed in low- and middle-income countries (LMICs) primarily due to the scarcity of advanced diagnostic tools. Several studies in PH have applied machine learning to low-cost diagnostic tools like 12-lead ECG (12L-ECG), but they mainly focus on areas with limited resources, overlooking areas with no...

Background Chronic thromboembolic pulmonary hypertension (CTEPH) is commonly evaluated using CT pulmonary angiography (CTPA). We evaluated the frequency and impact of parenchymal and cardiac abnormalities on survival in CTEPH. Methods Patients were identified from the ASPIRE (Assessing-the-Spectrum-of-Pulmonary-Hypertension-Identified-at-a-Referra...

Background Pulmonary hypertension (PH) is a heterogeneous condition and regardless of etiology impacts negatively on survival. Diagnosis of PH is based on hemodynamic parameters measured invasively at right heart catheterization (RHC); however, a non-invasive alternative would be clinically valuable. Our aim was to estimate RHC parameters non-invas...

Background Tricuspid regurgitation jet velocity (TRJV) on echocardiography is used for screening patients with suspected pulmonary hypertension (PH). Artificial intelligence (AI) tools, such as the US2.AI, have been developed for automated evaluation of echocardiograms and can yield measurements that aid PH detection. This study evaluated the perfo...

Recent advancements in non-invasive detection of cardiachemodynamic instability (CHDI) primarily focus on applying machinelearning techniques to a single data modality, e.g. cardiac magnetic res-onance imaging (MRI). Despite their potential, these approaches oftenfall short especially when the size of labeled patient data is limited, acommon challe...

(1) Background and Objectives: Flow assessment using cardiovascular magnetic resonance (CMR) provides important implications in determining physiologic parameters and clinically important markers. However, post-processing of CMR images remains labor- and time-intensive. This study aims to assess the validity and repeatability of fully automated seg...

Background High-resolution CT (HRCT) is central to the assessment of interstitial lung disease (ILD), and accurate classification of disease has important implications for patients. Evaluation of imaging features can be challenging, even for experienced thoracic radiologists. Previous work has provided equivocal evidence on the interpretation of HR...

Right Heart Catheterization is a gold standard procedure for diagnosing Pulmonary Hypertension by measuring mean Pulmonary Artery Pressure (mPAP). It is invasive, costly, time-consuming and carries risks. In this paper, for the first time, we explore the estimation of mPAP from videos of noninvasive Cardiac Magnetic Resonance Imaging. To enhance th...

Purpose The commonest cyanotic heart defect in childhood is Tetralogy of Fallot and following repair of this lesion patients frequently develop pulmonary regurgitation requiring pulmonary valve replacement (PVR). The purpose of this study was to utilise an artificial intelligence segmentation tool to automate the pulmonary artery (PA) measurements...

Objectives To assess the prognostic value of right ventricular (RV) remodelling defined with artificial intelligence (AI) derived RV volumetric and mass measurements on cardiac magnetic resonance (CMR) imaging in patients with pulmonary arterial hypertension (PAH). Methods Consecutive PAH patients underwent CMR assessment analysed using deep learn...

Background Cardiac magnetic resonance (CMR) in the four-chamber plane offers comprehensive insight into the volumetrics of the heart. We aimed to develop an artificial intelligence (AI) model of time-resolved segmentation using the four-chamber cine. Methods A fully automated deep learning algorithm was trained using retrospective multicentre and m...

Purpose To perform a systematic review and meta-analysis to assess the prognostic value of stress perfusion cardiac MRI in predicting cardiovascular outcomes. Materials and Methods A systematic literature search from the inception of PubMed, Embase, Web of Science, and China National Knowledge Infrastructure until January 2023 was performed for art...

Aims Heart failure (HF) with preserved ejection fraction disproportionately affects women. There are no validated sex-specific tools for HF diagnosis despite widely reported differences in cardiac structure. This study investigates whether sex, as assigned at birth, influences cardiac magnetic resonance (CMR) assessment of left ventricular filling...

Background Chronic pulmonary embolism (PE) may result in pulmonary hypertension (CTEPH). Automated CT pulmonary angiography (CTPA) interpretation using artificial intelligence (AI) tools has the potential for improving diagnostic accuracy, reducing delays to diagnosis and yielding novel information of clinical value in CTEPH. This systematic review...

Radiology: Cardiothoracic Imaging publishes novel research and technical developments in cardiac, thoracic, and vascular imaging. The journal published many innovative studies during 2023 and achieved an impact factor for the first time since its inaugural issue in 2019, with an impact factor of 7.0. The current review article, led by the Radiology...

Introduction Mortality from heart failure (HF) remains unacceptably high.¹ Left ventricular (LV) ejection fraction (EF) is a flawed, surrogate marker of function.² Pressure- Volume (PV) loops permit comprehensive study of myocardial energetics, stiffness and loading conditions. PV-loops can be assessed invasively but this is laborious and carries r...

Purpose: The main objective of this study was to develop two-dimensional (2D) phase contrast (PC) methods to quantify the helicity and vorticity of blood flow in the aortic root. Methods: This proof-of-concept study used four-dimensional (4D) flow cardiovascular MR (4D flow CMR) data of five healthy controls, five patients with heart failure with...

Introduction Cardiac magnetic resonance (CMR) is of diagnostic and prognostic value in a range of cardiopulmonary conditions. Current methods for evaluating CMR studies are laborious and time-consuming, contributing to delays for patients. As the demand for CMR increases, there is a growing need to automate this process. The application of artifici...

Background Diagnostic rates and risk factors for the subsequent development of chronic thromboembolic pulmonary hypertension (CTEPH) following pulmonary embolism (PE) are not well defined. Methods Over a 10-year period (2010–2020), consecutive patients attending a PE follow-up clinic in Sheffield (population 554 600) and all patients diagnosed wit...

Background There is clinical need to better quantify lung disease severity in pulmonary hypertension (PH), particularly in idiopathic pulmonary arterial hypertension (IPAH) and PH associated with lung disease (PH-LD). Purpose To quantify fibrosis on CT pulmonary angiograms using an artificial intelligence (AI) model and to assess whether this appro...

Background Balancing the risk of bleeding and thrombosis after acute myocardial infarction (AMI) is challenging, and the optimal antithrombotic therapy remains uncertain. The potential of non‐vitamin K antagonist oral anticoagulants (NOACs) to prevent ischaemic cardiovascular events is promising, but the evidence remains limited. Objectives To eva...

Background Segmentation of cardiac structures is an important step in evaluation of the heart on imaging. There has been growing interest in how artificial intelligence (AI) methods—particularly deep learning (DL)—can be used to automate this process. Existing AI approaches to cardiac segmentation have mostly focused on cardiac MRI. This systematic...

Aims Blood pressure (BP) is a crucial factor in cardiovascular health and can affect cardiac imaging assessments. However, standard outpatient cardiovascular MR (CMR) imaging procedures do not typically include BP measurements prior to image acquisition. This study proposes that brachial systolic BP (SBP) and diastolic BP (DBP) can be modelled usin...

Background Balancing the risk of bleeding and thrombosis after acute myocardial infarction (AMI) is challenging and the optimal antithrombotic therapy remains uncertain. The potential of NOACs to prevent ischaemic cardiovascular events is promising but evidence remains limited. Purpose To assess the efficacy and safety of NOACs in addition to back...

Objectives Early identification of lung cancer on chest radiographs improves patient outcomes. Artificial intelligence (AI) tools may increase diagnostic accuracy and streamline this pathway. This study evaluated the performance of commercially available AI-based software trained to identify cancerous lung nodules on chest radiographs. Design This...

Introduction: PAH is a deadly disease without cure. Formalized risk stratification allows therapeutic adjustments that optimize drug utilization. Risk scores, like REVEAL 2.0 recommended by PAH guidelines only offer good discrimination. Our goal was to create risk models with excellent discrimination (C-Index over 0.8), using modern statistical tec...

Background and objectives: Evaluating left ventricular filling pressure (LVFP) plays a crucial role in diagnosing and managing heart failure (HF). While traditional assessment methods involve multi-parametric transthoracic echocardiography (TTE) or right heart catheterisation (RHC), cardiovascular magnetic resonance (CMR) has emerged as a valuable...

Introduction: The purpose of this study was to investigate the differences in pulmonary vascular tree structures between control patients, patients with pulmonary arterial hypertension (PAH) and those with chronic thromboembolic pulmonary hypertension (CTEPH) using computed tomography (CT) pulmonary vessel analysis. Methods: This retrospective st...

Heart failure is a severe and life-threatening condition that can lead to elevated pressure in the left ventricle. Pulmonary Arterial Wedge Pressure (PAWP) is an important surrogate marker indicating high pressure in the left ventricle. PAWP is determined by Right Heart Catheterization (RHC) but it is an invasive procedure. A non-invasive method is...

Objectives There is a need for CT pulmonary angiography (CTPA) lung segmentation models. Clinical translation requires radiological evaluation of model outputs, understanding of limitations, and identification of failure points. This multicentre study aims to develop an accurate CTPA lung segmentation model, with evaluation of outputs in two divers...

Right ventricular (RV) function is critical to prognosis in all forms of pulmonary hypertension. Here we perform molecular phenotyping of RV remodeling by transcriptome analysis of RV tissue obtained from 40 individuals, and two animal models of RV dysfunction of both sexes. Our unsupervised clustering analysis identified ‘early’ and ‘late’ subgrou...

Introduction To identify minimally important differences (MIDs) for cardiac MRI metrics based on FDA recommendations for a clinical outcome measure that should reflect how a patient feels, functions or survives. Methods Consecutive treatment-naïve patients with pulmonary arterial hypertension between 2010 and 2022 who had two cardiac MRI scans (at...

Aims: Left ventricular filling pressure (LVFP) can be estimated from cardiovascular magnetic resonance (CMR). We aimed to investigate whether CMR-derived LVFP is associated with signs, symptoms, and prognosis in patients with recently diagnosed heart failure (HF). Methods and results: This study recruited 454 patients diagnosed with HF who under...

Introduction Cardiac MRI (CMR) is the gold standard technique to assess bi-ventricular volumes and function and is increasingly being considered as an endpoint in clinical studies. Currently, with the exception of right ventricle (RV) stroke volume and RV end-diastolic volume, there is only limited data on minimally important differences (MIDs) rep...

Abstract Introduction Although widely adopted in clinical practice, the left ventricular ejection fraction (LVEF) has significant limitations in heart failure assessment1. Gold standard physiological measures of heart function utilise pressure-volume (PV) loops, particularly the stroke work (SW), represented as the area bounded by the loop. Invasiv...

Purpose of Review The right ventricle (RV) has a complex geometry and physiology which is distinct from the left. RV dysfunction and failure can be the aftermath of volume- and/or pressure-loading conditions, as well as myocardial and pericardial diseases. Recent Findings Echocardiography, magnetic resonance imaging and right heart catheterisation...

Objective To investigate whether left atrial (LA) volume and left ventricular filling pressure (LVFP) assessed by cardiovascular magnetic resonance (CMR) change during adenosine delivered myocardial hyperaemia as part of a first-pass stress perfusion study. Methods and results We enrolled 33 patients who had stress CMR. These patients had a baseli...

Introduction Severe pulmonary hypertension (mean pulmonary artery pressure ≥35 mmHg) in chronic lung disease (PH-CLD) is associated with high mortality and morbidity. Data suggesting potential response to vasodilator therapy in patients with PH-CLD is emerging. The current diagnostic strategy utilises transthoracic Echocardiography (TTE), which can...

Background: Current cardiac magnetic resonance (CMR) imaging in pulmonary arterial hypertension (PAH) focuses on measures of ventricular function and coupling. Objectives: The purpose of this study was to evaluate pulmonary artery (PA) global longitudinal strain (GLS) as a prognostic marker in patients with PAH. Methods: The authors included 1...

Purpose: Lung disease assessment in precapillary pulmonary hypertension (PH) is essential for appropriate patient management. This study aims to develop an artificial intelligence (AI) deep learning model for lung texture classification in CT Pulmonary Angiography (CTPA), and evaluate its correlation with clinical assessment methods. Materials and...

Heart failure is a serious and life-threatening condition that can lead to elevated pressure in the left ventricle. Pulmonary Arterial Wedge Pressure (PAWP) is an important surrogate marker indicating high pressure in the left ventricle. PAWP is determined by Right Heart Catheterization (RHC) but it is an invasive procedure. A non-invasive method i...

Recent studies have recognized the importance of characterizing the extent of lung disease in pulmonary hypertension patients by using Computed Tomography. The trustworthiness of an artificial intelligence system is linked with the depth of the evaluation in functional, operational, usability, safety and validation dimensions. The safety and valida...

Coronary artery disease (CAD) remains a leading cause of mortality and morbidity worldwide, and it is associated with considerable economic burden. In an ageing, multimorbid population, it has become increasingly important to develop reliable, consistent, low-risk, non-invasive means of diagnosing CAD. The evolution of multiple cardiac modalities i...

Background: Ischaemia with nonobstructive coronary arteries is most commonly caused by coronary microvascular dysfunction but remains difficult to diagnose without invasive testing. Myocardial blood flow (MBF) can be quantified noninvasively on stress perfusion cardiac magnetic resonance (CMR) or positron emission tomography but neither is routine...

Recent years have seen a dramatic increase in studies presenting artificial intelligence (AI) tools for cardiac imaging. Amongst these are AI tools that undertake segmentation of structures on cardiac MRI (CMR), an essential step in obtaining clinically relevant functional information. The quality of reporting of these studies carries significant i...

Introduction Cardiac MRI (CMR) is the gold standard technique to assess bi-ventricular volumes and function and is increasingly being considered as an end-point in clinical studies. Currently, with the exception of right ventricle (RV) stroke volume, there are no minimally important differences (MIDs) reported for CMR metrics in pulmonary arterial...

There remains a debate whether the ventricular volume within prolapsing mitral valve (MV) leaflets should be included in the left ventricular (LV) end-systolic volume, and therefore factored in LV stroke volume (SV), in cardiac magnetic resonance (CMR) assessments. This study aims to compare LV volumes during end-systolic phases, with and without t...

Abstract Background Measurement of peak velocities is important in the evaluation of heart failure. This study compared the performance of automated 4D flow cardiac MRI (CMR) with traditional transthoracic Doppler echocardiography (TTE) for the measurement of mitral inflow peak diastolic velocities. Methods Patients with Doppler echocardiography an...

Objectives Right ventricle (RV) mass is an imaging biomarker of mean pulmonary artery pressure (MPAP) and pulmonary vascular resistance (PVR). Some methods of RV mass measurement on cardiac MRI (CMR) exclude RV trabeculation. This study assessed the reproducibility of measurement methods and evaluated whether the inclusion of trabeculation in RV ma...

Pulmonary Arterial Hypertension (PAH) is a lifethreatening disorder. The prediction of mortality in PAH patients can play a crucial role in the clinical management of this disease. The prediction of mortality from one modality is a difficult task that may only provide limited performance. Therefore, we propose a multimodal learning approach in this...

Background Right atrial (RA) area predicts mortality in patients with pulmonary hypertension, and is recommended by the European Society of Cardiology/European Respiratory Society pulmonary hypertension guidelines. The advent of deep learning may allow more reliable measurement of RA areas to improve clinical assessments. The aim of this study was...

Objectives To determine the prognostic value of patterns of right ventricular (RV) adaptation in patients with pulmonary arterial hypertension (PAH), assessed using cardiac magnetic resonance (CMR) imaging at baseline and follow-up. Methods Consecutive patients with PAH from the ASPIRE registry were included in the baseline cohort. Patients who re...

Introduction Cardiac MRI (CMR) is the gold standard technique to assess bi-ventricular volumes and function and is increasingly being considered as an end-point in clinical studies. Currently, with the exception of right ventricle (RV) stroke volume, there are no minimally important differences (MIDs) reported for CMR metrics. Our study aimed to id...

Background CT pulmonary angiography (CTPA) is recommended in suspected chronic thromboembolic pulmonary hypertension (CTEPH) and supports therapeutic planning. Mosaic perfusion and lung scarring are common features in CTEPH, but their clinical relevance is less understood. CTEPH is a challenging diagnosis and a commonly overlooked condition that’s...

Objectives Right ventricular (RV) dysfunction carries elevated risk in acute pulmonary embolism (PE). An increased ratio between the size of the right and left ventricles (RV/LV ratio) is a biomarker of RV dysfunction. This study evaluated the reproducibility of RV/LV ratio measurement on CT pulmonary angiography (CTPA). Methods 20 inpatient CTPA...

Introduction Computed tomography pulmonary angiography (CTPA) is an essential test in the work-up of suspected pulmonary vascular disease including pulmonary hypertension and pulmonary embolism. Cardiac and great vessel assessments on CTPA are based on visual assessment and manual measurements which are known to have poor reproducibility. The prima...

Objective Cardiac pathologies are increasingly identified on general body computed tomography (CT). This trend is driven by advancements in CT techniques improving non-gated image quality combined with the vast increase in CT imaging over recent years. We aimed to assess reported cardiac findings on general body CT. Methods The reports of all CT s...

Background Cardiac MRI measurements have diagnostic and prognostic value in the evaluation of cardiopulmonary disease. Artificial intelligence approaches to automate cardiac MRI segmentation are emerging but require clinical testing. Purpose To develop and evaluate a deep learning tool for quantitative evaluation of cardiac MRI functional studies a...

Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): This work was supported by an NIHR AI Award, AI_AWARD01706. This research was also funded in part, by the Wellcome Trust [Grant number 205188/Z/16/Z ]. Background There has been a rapid increase in the number of Artificial Intelligence (AI) studies of...

Background and Objectives: Interest in artificial intelligence (AI) for outcome prediction has grown substantially in recent years. However, the prognostic role of AI using advanced cardiac magnetic resonance imaging (CMR) remains unclear. This systematic review assesses the existing literature on AI in CMR to predict outcomes in patients with card...