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result(s) for
"McCann, Gerry P"
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Cardiovascular magnetic resonance: applications and practical considerations for the general cardiologist
by
McCann, Gerry P
,
Arnold, Jayanth Ranjit
in
Aneurysms
,
Atrial Function
,
cardiac magnetic resonance (CMR) imaging
2020
Cardiovascular magnetic resonance (CMR) is a rapidly evolving non-invasive imaging modality offering comprehensive, multiparametric assessment of cardiac structure and function in a variety of clinical situations. Cine imaging with CMR is the gold standard non-invasive imaging technique for the quantification of ventricular volumes and systolic function. It also affords superior visualisation of apical and right ventricular morphological abnormalities. In coronary artery disease, CMR stress perfusion imaging identifies functionally significant coronary artery disease with high sensitivity and specificity, and international guidelines recommend CMR perfusion imaging in patients with chest pain at intermediate-high risk of coronary disease. Late gadolinium enhancement (LGE) imaging is the most sensitive imaging technique for identifying infarction/viability. In non-ischaemic cardiomyopathy, LGE imaging plays vital diagnostic and prognostic roles in a number of cardiomyopathies (eg, hypertrophic and dilated cardiomyopathies, and amyloidosis). In vivo tissue characterisation with CMR enables the identification of oedema/inflammation in acute coronary syndromes/myocarditis and the diagnosis of chronic fibrotic conditions (eg, in hypertrophic and dilated cardiomyopathy, aortic stenosis and amyloidosis). CMR T2* imaging uniquely offers non-invasive assessment of iron overload states, facilitating diagnosis and management. A multiparametric CMR approach also enables differentiation of cardiac masses/tumours and is a useful adjunct to echocardiography in the assessment of valve disease. The emergence of automated, inline, quantitative methodologies will expand the scope of CMR and reduce its cost in forthcoming years.
Journal Article
Epicardial adipose tissue in obesity-related cardiac dysfunction
by
McCann, Gerry P
,
Ayton, Sarah L
,
Gulsin, Gaurav S
in
Adipocytes
,
Adipose Tissue - metabolism
,
biomarkers
2022
Obesity is associated with the development of heart failure and is a major risk factor for heart failure with preserved ejection fraction (HFpEF). Epicardial adipose tissue (EAT) is a unique visceral fat in close proximity to the heart and is of particular interest to the study of cardiac disease. Small poorly differentiated adipocytes with altered lipid:water content are associated with a proinflammatory secretome and may contribute to the pathophysiology observed in HFpEF. Multimodality imaging approaches can be used to quantify EAT volume and characterise EAT composition. Current research studies remain unclear as to the magnitude of effect that EAT plays on myocardial dysfunction and further work using multimodality imaging techniques is ongoing. Pharmacological interventions, including glucagon-like peptide 1 receptor agonists and sodium-dependent glucose linked transporter 2 inhibitors have shown promise in attenuating the deleterious metabolic and inflammatory changes seen in EAT. Clinical studies are ongoing to explore whether these therapies exert their beneficial effects by modifying this unique adipose deposit.
Journal Article
Diabetic cardiomyopathy: prevalence, determinants and potential treatments
by
Gulsin, Gaurav S.
,
McCann, Gerry P.
,
Athithan, Lavanya
in
Abnormalities
,
Aerobic capacity
,
Blood
2019
The prevalence of type 2 diabetes (T2D) has reached a pandemic scale. These patients are at a substantially elevated risk of developing cardiovascular disease, with heart failure (HF) being a leading cause of morbidity and mortality. Even in the absence of traditional risk factors, diabetes still confers up to a twofold increased risk of developing HF. This has led to identifying diabetes as an independent risk factor for HF and recognition of the distinct clinical entity, diabetic cardiomyopathy. Despite a wealth of research interest, the prevalence and determinants of diabetic cardiomyopathy remain uncertain. This limited understanding of the pathophysiology of diabetic heart disease has also hindered development of effective treatments. Tight blood-glucose and blood-pressure control have not convincingly been shown to reduce macrovascular outcomes in T2D. There is, however, emerging evidence that T2D is reversible and that the metabolic abnormalities can be reversed with weight loss. Increased aerobic exercise capacity is associated with significantly lower cardiovascular and overall mortality in diabetes. Whether such lifestyle modifications as weight loss and exercise may ameliorate the structural and functional derangements of the diabetic heart has yet to be established. In this review, the link between T2D and myocardial dysfunction is explored. Insights into the structural and functional perturbations that typify the diabetic heart are first described. This is followed by an examination of the pathophysiological mechanisms that contribute to the development of cardiovascular disease in T2D. Lastly, the current and emerging therapeutic strategies to prevent or ameliorate cardiac dysfunction in T2D are evaluated.
Journal Article
A Panel of 4 microRNAs Facilitates the Prediction of Left Ventricular Contractility after Acute Myocardial Infarction
2013
Prediction of clinical outcome after acute myocardial infarction (AMI) is challenging and would benefit from new biomarkers. We investigated the prognostic value of 4 circulating microRNAs (miRNAs) after AMI.
We enrolled 150 patients after AMI. Blood samples were obtained at discharge for determination of N-terminal pro-brain natriuretic peptide (Nt-proBNP) and levels of miR-16, miR-27a, miR-101 and miR-150. Patients were assessed by echocardiography at 6 months follow-up and the wall motion index score (WMIS) was used as an indicator of left ventricular (LV) contractility. We assessed the added predictive value of miRNAs against a multi-parameter clinical model including Nt-proBNP.
Patients with anterior AMI and elevated Nt-proBNP levels at discharge from the hospital were at high risk of subsequent impaired LV contractility (follow-up WMIS>1.2, n = 71). A combination of the 4 miRNAs (miR-16/27a/101/150) improved the prediction of LV contractility based on clinical variables (P = 0.005). Patients with low levels of miR-150 (odds ratio [95% confidence interval] 0.08 [0.01-0.48]) or miR-101 (0.19 [0.04-0.97]) and elevated levels of miR-16 (15.9 [2.63-95.91]) or miR-27a (4.18 [1.36-12.83]) were at high risk of impaired LV contractility. The 4 miRNA panel reclassified a significant proportion of patients with a net reclassification improvement of 66% (P = 0.00005) and an integrated discrimination improvement of 0.08 (P = 0.001).
Our results indicate that panels of miRNAs may aid in prognostication of outcome after AMI.
Journal Article
Role of inflammation in diabetic cardiomyopathy
2022
The prevalence of type 2 diabetes (T2D) has reached a pandemic scale. Systemic chronic inflammation dominates the diabetes pathophysiology and has been implicated as a causal factor for the development of vascular complications. Heart failure (HF) is regarded as the most common cardiovascular complication of T2D and the diabetic diagnosis is an independent risk factor for HF development. Key molecular mechanisms pivotal to the development of diabetic cardiomyopathy include the NF-κB pathway and renin–angiotensin–aldosterone system, in addition to advanced glycation end product accumulation and inflammatory interleukin overexpression. Chronic myocardial inflammation in T2D mediates structural and metabolic changes, including cardiomyocyte apoptosis, impaired calcium handling, myocardial hypertrophy and fibrosis, all of which contribute to the diabetic HF phenotype. Advanced cardiovascular magnetic resonance imaging (CMR) has emerged as a gold standard non-invasive tool to delineate myocardial structural and functional changes. This review explores the role of chronic inflammation in diabetic cardiomyopathy and the ability of CMR to identify inflammation-mediated myocardial sequelae, such as oedema and diffuse fibrosis.
Journal Article
Reproducibility of left atrial function using cardiac magnetic resonance imaging
by
Graham-Brown, Mathew P.
,
Gulsin, Gaurav S.
,
Singh, Anvesha
in
Aorta
,
Aortic stenosis
,
Atrial Function, Left
2021
Objectives
To determine the test-retest reproducibility and observer variability of CMR-derived LA function, using (i) LA strain (LAS) and strain rate (LASR), and (ii) LA volumes (LAV) and emptying fraction (LAEF).
Methods
Sixty participants with and without cardiovascular disease (aortic stenosis (AS) (
n
= 16), type 2 diabetes (T2D) (
n
= 28), end-stage renal disease on haemodialysis (
n
= 10) and healthy volunteers (
n
= 6)) underwent two separate CMR scans 7–14 days apart. LAS and LASR, corresponding to LA reservoir, conduit and contractile booster-pump function, were assessed using Feature Tracking software (QStrain v2.0). LAEF was calculated using the biplane area length method (QMass v8.1). Both were assessed using 4- and 2-chamber long-axis standard steady-state free precession cine images, and average values were calculated. Intra- and inter-observer variabilities were assessed in 10 randomly selected participants.
Results
The test-retest reproducibility was moderate to poor for all strain and strain rate parameters. Overall, strain and strain rate corresponding to reservoir phase (LAS_r, LASR_r) were the most reproducible, yielding the smallest coefficient of variance (CoV) (29.9% for LAS_r, 28.9% for LASR_r). The test-retest reproducibility for LAVs and LAEF was good: LAVmax CoV = 19.6% ICC = 0.89, LAVmin CoV = 27.0% ICC = 0.89 and total LAEF CoV = 15.6% ICC = 0.78. The inter- and intra-observer variabilities were good for all parameters except for conduit function.
Conclusion
The test-retest reproducibility of LA strain and strain rate assessment by CMR utilising Feature Tracking is moderate to poor across disease states, whereas LA volume and emptying fraction are more reproducible on CMR. Further improvements in LA strain quantification are needed before widespread clinical application.
Key Points
•
LA strain and strain rate assessment using Feature Tracking on CMR has moderate to poor test-retest reproducibility across disease states.
•
The test-retest reproducibility for the biplane method of assessing LA function is better than strain assessment, with lower coefficient of variances and narrower limits of agreement on Bland-Altman plots.
•
Biplane LA volumetric measurement also has better intra- and inter-observer variability compared to strain assessment.
Journal Article
Society for Cardiovascular Magnetic Resonance (SCMR) expert consensus for CMR imaging endpoints in clinical research: part I - analytical validation and clinical qualification
2018
Cardiovascular disease remains a leading cause of morbidity and mortality globally. Changing natural history of the disease due to improved care of acute conditions and ageing population necessitates new strategies to tackle conditions which have more chronic and indolent course. These include an increased deployment of safe screening methods, life-long surveillance, and monitoring of both disease activity and tailored-treatment, by way of increasingly personalized medical care. Cardiovascular magnetic resonance (CMR) is a non-invasive, ionising radiation-free method, which can support a significant number of clinically relevant measurements and offers new opportunities to advance the state of art of diagnosis, prognosis and treatment. The objective of the SCMR Clinical Trial Taskforce was to summarizes the evidence to emphasize where currently CMR-guided clinical care can indeed translate into meaningful use and efficient deployment of resources results in meaningful and efficient use. The objective of the present initiative was to provide an appraisal of evidence on
analytical validation
, including the accuracy and precision, and
clinical qualification
of parameters in disease context, clarifying the strengths and weaknesses of the state of art, as well as the gaps in the current evidence This paper is complementary to the existing position papers on standardized acquisition and post-processing ensuring robustness and transferability for widespread use. Themed imaging-endpoint guidance on trial design to support drug-discovery or change in clinical practice (part II), will be presented in a follow-up paper in due course. As CMR continues to undergo rapid development, regular updates of the present recommendations are foreseen.
Journal Article
A systematic review of micro‐RNAs in aortic stenosis and cardiac fibrosis
by
Singh, Anvesha
,
Murphy, Gavin
,
Adewuyi, Jemima Osekafore
in
Aortic stenosis
,
Aortic valve
,
Aortic valve stenosis
2022
Aortic stenosis (AS) is the commonest valve lesion requiring surgery in the Western world. The presence of myocardial fibrosis is associated with mortality even after valve replacement. MicroRNAs could serve as biomarkers of fibrosis and risk stratify patients for earlier intervention. This study aimed to systematically review reports of micro‐RNA (miR) associated with fibrosis in AS and identify potential biomarkers. We searched EMBASE, Medline, and Web of Science up to May 2020. Studies that reported on the role of miRs in AS and cardiac fibrosis were included. Study quality was assessed using the Newcastle‐Ottawa scale. Of 4230 reports screened, 25 were included. All studies were of low to moderate quality. MiRs were analyzed in myocardial tissue (n = 10), aortic valve tissue (n = 5), plasma (n = 5), and serum (n = 5). A total of 365 miRs were reported, of which only a few were reported in more than one paper (3 in the myocardium, 5 in the aortic valve, and 1 in plasma). miR‐21 was upregulated in plasma and myocardial tissue. MiR‐19b was downregulated in the myocardium. Papers reporting myocardial miR‐1 contradicted each other, and miR‐133a was associated with increased left ventricular mass regression post‐surgery. In the aortic valve, miRs‐665, 602 and 939 were downregulated, and miRs‐193b and 214 were upregulated. The data on miR in fibrosis in AS is scarce and of low to moderate quality. Further studies are needed to identify novel miRs as biomarkers, especially at an earlier asymptomatic phase of the disease.
Journal Article
Characterizing heart failure with preserved and reduced ejection fraction: An imaging and plasma biomarker approach
by
Gulsin, Gaurav S.
,
Ng, Leong L.
,
McCann, Gerry P.
in
Aged
,
Aged, 80 and over
,
Biology and Life Sciences
2020
The pathophysiology of heart failure with preserved ejection fraction (HFpEF) remains incompletely defined. We aimed to characterize HFpEF compared to heart failure with reduced ejection fraction (HFrEF) and asymptomatic hypertensive or non-hypertensive controls.
Prospective, observational study of 234 subjects (HFpEF n = 140; HFrEF n = 46, controls n = 48, age 73±8, males 49%) who underwent echocardiography, cardiovascular magnetic resonance imaging (CMR), plasma biomarker analysis (panel of 22) and 6-minute walk testing (6MWT). The primary end-point was the composite of all-cause mortality and/or HF hospitalization.
Compared to controls both HF groups had lower exercise capacity, lower left ventricular (LV) EF, higher LV filling pressures (E/E', B-type natriuretic peptide [BNP], left atrial [LA] volumes), more right ventricular (RV) systolic dysfunction, more focal and diffuse fibrosis and higher levels of all plasma markers. LV remodeling (mass/volume) was different between HFpEF (concentric, 0.68±0.16) and HFrEF (eccentric, 0.47±0.15); p<0.0001. Compared to controls, HFpEF was characterized by (mild) reductions in LVEF, more myocardial fibrosis, LA remodeling/dysfunction and RV dysfunction. HFrEF patients had lower LVEF, increased LV volumes, greater burden of focal and diffuse fibrosis, more RV remodeling, lower LAEF and higher LA volumes compared to HFpEF. Inflammatory/fibrotic/renal dysfunction plasma markers were similarly elevated in both HF groups but markers of cardiomyocyte stretch/damage (BNP, pro-BNP, N-terminal pro-atrial natriuretic peptide and troponin-I) were higher in HFrEF compared to HFpEF; p<0.0001. Focal fibrosis was associated with galectin3, GDF-15, MMP-3, MMP-7, MMP-8, BNP, pro-BNP and NTproANP; p<0.05. Diffuse fibrosis was associated with GDF-15, Tenascin-C, MMP-2, MMP-3, MMP-7, BNP, proBNP and NTproANP; p<0.05. Composite event rates (median 1446 days follow-up) did not differ between HFpEF and HFrEF (Log-Rank p = 0.784).
HFpEF is a distinct pathophysiological entity compared to age- and sex-matched HFrEF and controls. HFpEF and HFrEF are associated with similar adverse outcomes. Inflammation is common in both HF phenotypes but cardiomyocyte stretch/stress is greater in HFrEF.
Journal Article
Diagnostic and prognostic utility of cardiovascular magnetic resonance imaging in heart failure with preserved ejection fraction – implications for clinical trials
by
McAdam, John
,
Cheng, Adrian S. H.
,
Singh, Anvesha
in
Adenosine - administration & dosage
,
Adult
,
Aged
2018
Background
Heart failure with preserved ejection fraction (HFpEF) is a poorly characterized condition. We aimed to phenotype patients with HFpEF using multiparametric stress cardiovascular magnetic resonance imaging (CMR) and to assess the relationship to clinical outcomes.
Methods
One hundred and fifty four patients (51% male, mean age 72 ± 10 years) with a diagnosis of HFpEF underwent transthoracic echocardiography and CMR during a single study visit. The CMR protocol comprised cine, stress/rest perfusion and late gadolinium enhancement imaging on a 3T scanner. Follow-up outcome data (death and heart failure hospitalization) were captured after a minimum of 6 months.
Results
CMR detected previously undiagnosed pathology in 42 patients (27%), who had similar baseline characteristics to those without a new diagnosis. These diagnoses consisted of: coronary artery disease (
n
= 20, including 14 with ‘silent’ infarction), microvascular dysfunction (
n
= 11), probable or definite hypertrophic cardiomyopathy (
n
= 10) and constrictive pericarditis (
n
= 5). Four patients had dual pathology. During follow-up (median 623 days), patients with a new CMR diagnosis were at higher risk of adverse outcome for the composite endpoint (log rank test:
p
= 0.047). In multivariate Cox proportional hazards analysis, a new CMR diagnosis was the strongest independent predictor of adverse outcome (hazard ratio: 1.92; 95% CI: 1.07 to 3.45;
p
= 0.03).
Conclusions
CMR diagnosed new significant pathology in 27% of patients with HFpEF. These patients were at increased risk of death and heart failure hospitalization.
Trial registration
ClinicalTrials.gov Identifier:
NCT03050593
. Retrospectively registered; Date of registration: February 06, 2017.
Journal Article