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Journal articleAhmadvazir S, Shah BN, Zacharias K, et al., 2017,
Incremental prognostic value of stress echocardiography with carotid ultrasound for suspected CAD.
, JACC Cardiovasc Imaging, Vol: 11, Pages: 173-180, ISSN: 1936-878XOBJECTIVES: This study hypothesized that ischemia and atherosclerosis assessment by ultrasound (US) may provide incremental prognostic information in patients with new-onset chest pain who do not have coronary artery disease (CAD). BACKGROUND: The clinical significance of atherosclerosis assessment by carotid US in patients undergoing stress echocardiography (SE) in such patients is unknown. METHODS: Consecutive patients with suspected angina but no history of CAD underwent simultaneous SE and US prospectively to assess myocardial ischemia and carotid plaque burden (CPB), respectively. Patients were followed up for major adverse events (MAEs)-all-cause mortality, nonfatal myocardial infarction, and unplanned coronary revascularization. RESULTS: Of 591 recruited patients, 580 (men, 46%; mean age 59 ± 11 years) patients were available for follow-up. SE demonstrated myocardial ischemia in 12%, but prevalence of carotid plaques was 59%. During a mean follow-up of 1,117 ± 361 days, 40 first MAEs occurred. In the multivariable regression model, pre-test probability (PTP) of CAD (p = 0.001), abnormal SE (p < 0.0001), and CPB (p < 0.0001) predicted MAEs. MAE rates per year increased from 0.9% versus 1.97% versus 4.3% versus 9.7% in patients with no carotid plaque and normal SE versus patients who had plaque and normal SE versus those with no plaque and abnormal SE versus patients with plaque and abnormal SE, respectively (p < 0.0001). In hierarchical analysis, plaque burden provided incremental prognostic value over PTP of CAD and SE; likewise, SE was incremental to PTP-CAD and CPB (p < 0.0001 for both). CONCLUSIONS: In patients with suspected stable angina without known CAD, simultaneous SE (for ischemia) and US (for atherosclerosis) provided incremental prognostic value.
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Journal articleTayal U, Prasad S, Cook SA, 2017,
Genetics and genomics of dilated cardiomyopathy and systolic heart failure
, GENOME MEDICINE, Vol: 9, ISSN: 1756-994XHeart failure is a major health burden, affecting 40 million people globally. One of the main causes of systolic heart failure is dilated cardiomyopathy (DCM), the leading global indication for heart transplantation. Our understanding of the genetic basis of both DCM and systolic heart failure has improved in recent years with the application of next-generation sequencing and genome-wide association studies (GWAS). This has enabled rapid sequencing at scale, leading to the discovery of many novel rare variants in DCM and of common variants in both systolic heart failure and DCM. Identifying rare and common genetic variants contributing to systolic heart failure has been challenging given its diverse and multiple etiologies. DCM, however, although rarer, is a reasonably specific and well-defined condition, leading to the identification of many rare genetic variants. Truncating variants in titin represent the single largest genetic cause of DCM. Here, we review the progress and challenges in the detection of rare and common variants in DCM and systolic heart failure, and the particular challenges in accurate and informed variant interpretation, and in understanding the effects of these variants. We also discuss how our increasing genetic knowledge is changing clinical management. Harnessing genetic data and translating it to improve risk stratification and the development of novel therapeutics represents a major challenge and unmet critical need for patients with heart failure and their families.
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Journal articleNielles-Vallespin S, Khalique Z, Ferreira PF, et al., 2017,
Assessment of myocardial microstructural dynamics by in vivo diffusion tensor cardiac magnetic resonance
, Journal of the American College of Cardiology, Vol: 69, Pages: 661-676, ISSN: 0735-1097BackgroundCardiomyocytes are organized in microstructures termed sheetlets that reorientate during left ventricular thickening. Diffusion tensor cardiac magnetic resonance (DT-CMR) may enable noninvasive interrogation of in vivo cardiac microstructural dynamics. Dilated cardiomyopathy (DCM) is a condition of abnormal myocardium with unknown sheetlet function.ObjectivesThis study sought to validate in vivo DT-CMR measures of cardiac microstructure against histology, characterize microstructural dynamics during left ventricular wall thickening, and apply the technique in hypertrophic cardiomyopathy (HCM) and DCM.MethodsIn vivo DT-CMR was acquired throughout the cardiac cycle in healthy swine, followed by in situ and ex vivo DT-CMR, then validated against histology. In vivo DT-CMR was performed in 19 control subjects, 19 DCM, and 13 HCM patients.ResultsIn swine, a DT-CMR index of sheetlet reorientation (E2A) changed substantially (E2A mobility ∼46°). E2A changes correlated with wall thickness changes (in vivo r2 = 0.75; in situ r2 = 0.89), were consistently observed under all experimental conditions, and accorded closely with histological analyses in both relaxed and contracted states. The potential contribution of cyclical strain effects to in vivo E2A was ∼17%. In healthy human control subjects, E2A increased from diastole (18°) to systole (65°; p < 0.001; E2A mobility = 45°). HCM patients showed significantly greater E2A in diastole than control subjects did (48°; p < 0.001) with impaired E2A mobility (23°; p < 0.001). In DCM, E2A was similar to control subjects in diastole, but systolic values were markedly lower (40°; p < 0.001) with impaired E2A mobility (20°; p < 0.001).ConclusionsMyocardial microstructure dynamics can be characterized by in vivo DT-CMR. Sheetlet function was abnormal in DCM with altered systolic conformation and reduced mobility, contrasting with HCM, which showed reduced mobility with alte
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Journal articleSchafer S, de Marvao A, Adami E, et al., 2017,
Titin-truncating variants affect heart function in disease cohorts and the general population
, Nature Genetics, Vol: 49, Pages: 46-53, ISSN: 1546-1718Titin-truncating variants (TTNtv) commonly cause dilated cardiomyopathy (DCM). TTNtv are also encountered in ~1% of the general population, where they may be silent, perhaps reflecting allelic factors. To better understand TTNtv, we integrated TTN allelic series, cardiac imaging and genomic data in humans and studied rat models with disparate TTNtv. In patients with DCM, TTNtv throughout titin were significantly associated with DCM. Ribosomal profiling in rat showed the translational footprint of premature stop codons in Ttn, TTNtv-position-independent nonsense-mediated degradation of the mutant allele and a signature of perturbed cardiac metabolism. Heart physiology in rats with TTNtv was unremarkable at baseline but became impaired during cardiac stress. In healthy humans, machine-learning-based analysis of high-resolution cardiac imaging showed TTNtv to be associated with eccentric cardiac remodeling. These data show that TTNtv have molecular and physiological effects on the heart across species, with a continuum of expressivity in health and disease.
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Journal articleWare JS, Seidman JG, Arany Z, 2016,
Shared Genetic Predisposition in Peripartum and Dilated Cardiomyopathies REPLY
, New England Journal of Medicine, Vol: 374, Pages: 2601-2602, ISSN: 1533-4406 -
Journal articlePatel HC, Rosen SD, Hayward C, et al., 2016,
Renal denervation in heart failure with preserved ejection fraction (RDF-PEF): a randomised controlled trial
, European Journal of Heart Failure, Vol: 18, Pages: 703-712, ISSN: 1879-0844AimHeart failure with preserved ejection fraction (HFpEF) is associated with increased sympathetic nervous system (SNS) tone. Attenuating the SNS with renal denervation (RD) might be helpful and there are no data currently in humans with HFpEF.Methods and ResultsIn this single-centre, randomised, open-controlled study we included 25 patients with HFpEF (preserved left ventricular (LV) ejection fraction, left atrial (LA) dilatation or LV hypertrophy and raised B-type natriuretic peptide (BNP) or echocardiographic assessment of filling pressures). Patients were randomised (2:1) to RD with the Symplicity™ catheter or continuing medical therapy. The primary success criterion was not met in that there were no differences between groups at 12 months for Minnesota Living with Heart Failure Questionnaire score, peak oxygen uptake (VO2) on exercise, BNP, E/e’, LA volume index or LV mass index. A greater proportion of patients improved at three months in the RD group with respect to VO2 peak (56% vs 13%, P=0.025) and E/e’ (31% vs 13%, P=0.04). Change in estimated glomerular filtration rate was comparable between groups. Two patients required plain balloon angioplasty during the RD procedure to treat renal artery wall oedema.ConclusionThis study was terminated early due to difficulties in recruitment and was underpowered to detect whether RD improved the endpoints of: quality of life, exercise function, biomarkers and left heart remodelling. The procedure was safe in patients with HFpEF though two patients did require intra-procedure renal artery dilatation.
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Journal articleGrapsa J, Nunes MCP, Tan TC, et al., 2015,
Echocardiographic and Hemodynamic Predictors of Survival in Precapillary Pulmonary Hypertension Seven-Year Follow-Up
, CIRCULATION-CARDIOVASCULAR IMAGING, Vol: 8, ISSN: 1941-9651- Author Web Link
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- Citations: 31
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Journal articleSharma R, O'Driscoll JM, Saha A, et al., 2015,
Differing autonomic responses to dobutamine stress in the presence and absence of myocardial ischaemia
, JOURNAL OF PHYSIOLOGY-LONDON, Vol: 593, Pages: 2171-2184, ISSN: 0022-3751- Author Web Link
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- Citations: 3
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Journal articleRoberts AM, Ware JS, Herman DS, et al., 2015,
Integrated allelic, transcriptional, and phenomic dissection of the cardiac effects of titin truncations in health and disease
, Science Translational Medicine, Vol: 7, Pages: 270ra6-270ra6, ISSN: 1946-6234The recent discovery of heterozygous human mutations that truncate full-length titin (TTN, an abundant structural, sensory, and signaling filament in muscle) as a common cause of end-stage dilated cardiomyopathy (DCM) promises new prospects for improving heart failure management. However, realization of this opportunity has been hindered by the burden of TTN-truncating variants (TTNtv) in the general population and uncertainty about their consequences in health or disease. To elucidate the effects of TTNtv, we coupled TTN gene sequencing with cardiac phenotyping in 5267 individuals across the spectrum of cardiac physiology and integrated these data with RNA and protein analyses of human heart tissues. We report diversity of TTN isoform expression in the heart, define the relative inclusion of TTN exons in different isoforms (using the TTN transcript annotations available at http://cardiodb.org/titin), and demonstrate that these data, coupled with the position of the TTNtv, provide a robust strategy to discriminate pathogenic from benign TTNtv. We show that TTNtv is the most common genetic cause of DCM in ambulant patients in the community, identify clinically important manifestations of TTNtv-positive DCM, and define the penetrance and outcomes of TTNtv in the general population. By integrating genetic, transcriptome, and protein analyses, we provide evidence for a length-dependent mechanism of disease. These data inform diagnostic criteria and management strategies for TTNtv-positive DCM patients and for TTNtv that are identified as incidental findings.
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Journal articlePennell DJ, Porter JB, Piga A, et al., 2014,
A 1-year randomized controlled trial of deferasirox vs deferoxamine for myocardial iron removal in beta-thalassemia major (CORDELIA)
, Blood, Vol: 123, Pages: 1447-1454, ISSN: 0006-4971Randomized comparison data on the efficacy and safety of deferasirox for myocardial iron removal in transfusion dependent patients are lacking. CORDELIA was a prospective, randomized comparison of deferasirox (target dose 40 mg/kg per day) vs subcutaneous deferoxamine (50-60 mg/kg per day for 5-7 days/week) for myocardial iron removal in 197 β-thalassemia major patients with myocardial siderosis (T2* 6-20 milliseconds) and no signs of cardiac dysfunction (mean age, 19.8 years). Primary objective was to demonstrate noninferiority of deferasirox for myocardial iron removal, assessed by changes in myocardial T2* after 1 year using a per-protocol analysis. Geometric mean (Gmean) myocardial T2* improved with deferasirox from 11.2 milliseconds at baseline to 12.6 milliseconds at 1 year (Gmeans ratio, 1.12) and with deferoxamine (11.6 milliseconds to 12.3 milliseconds; Gmeans ratio, 1.07). The between-arm Gmeans ratio was 1.056 (95% confidence interval [CI], 0.998, 1.133). The lower 95% CI boundary was greater than the prespecified margin of 0.9, establishing noninferiority of deferasirox vs deferoxamine (P = .057 for superiority of deferasirox). Left ventricular ejection fraction remained stable in both arms. Frequency of drug-related adverse events was comparable between deferasirox (35.4%) and deferoxamine (30.8%). CORDELIA demonstrated the noninferiority of deferasirox compared with deferoxamine for myocardial iron removal. This trial is registered at www.clinicaltrials.gov as #NCT00600938.
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