References of "Mamas, Mamas A"
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See detailArterial access site utilization in cardiogenic shock in the United Kingdom: is radial access feasible?
Mamas, Mamas A.; Anderson, Simon G.; Ratib, Karim et al

in American heart journal (2014), 167(6), 900-81

BACKGROUND: Cardiogenic shock (CS) remains the leading cause of mortality in patients hospitalized with acute myocardial infarction (AMI). The transradial access site (TRA) has become increasingly adopted ... [more ▼]

BACKGROUND: Cardiogenic shock (CS) remains the leading cause of mortality in patients hospitalized with acute myocardial infarction (AMI). The transradial access site (TRA) has become increasingly adopted as a default access site for percutaneous coronary intervention (PCI); however, even in experienced centers that favor the radial artery as the primary access site during PCI, patients presenting in CS are often treated via the transfemoral access site (TFA); and commentators have suggested that CS remains the final frontier that has given even experienced radial operators pause. We studied the use of TRA in patients presenting in CS in a nonselected high-risk cohort from the British Cardiovascular Intervention database over a 7-year period (2006-2012). METHODS: Mortality (30-day) and major adverse cardiac and cerebrovascular events (a composite of in-hospital mortality, in-hospital myocardial reinfarction, target vessel revascularization, and cerebrovascular events) were studied based on TFA and TRA utilization in CS patients. The influence of access site selection was studied in 7,231 CS patients; TFA was used in 5,354 and TRA in 1,877 patients. RESULTS: Transradial access site was independently associated with a lower 30-day mortality (hazard ratio [HR] 0.56, 95% CI 0.46-0.69, P = 0 < .001), in-hospital major adverse cardiac and cerebrovascular events (HR 0.64, 95% CI 0.53-0.76, P < .0001) and major bleeding (HR 0.37, 95% CI 0.18-0.73, P = .004). CONCLUSIONS: Although the majority of PCI cases performed in patients with cardiogenic shock in the United Kingdom are performed through the TFA, the radial artery represents an alternative viable access site in this high-risk cohort of patients in experienced centers. [less ▲]

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See detailSerum sphingolipids level as a novel potential marker for early detection of human myocardial ischaemic injury.
Egom, Emmanuel E.; Mamas, Mamas A.; Chacko, Sanoj et al

in Frontiers in physiology (2013), 4

Background: Ventricular tachyarrhythmias are the most common and often the first manifestation of coronary heart disease and lead to sudden cardiac death (SCD). Early detection/identification of acute ... [more ▼]

Background: Ventricular tachyarrhythmias are the most common and often the first manifestation of coronary heart disease and lead to sudden cardiac death (SCD). Early detection/identification of acute myocardial ischaemic injury at risk for malignant ventricular arrhythmias in patients remains an unmet medical need. In the present study, we examined the sphingolipids level after transient cardiac ischaemia following temporary coronary artery occlusion during percutaneous coronary intervention (PCI) in patients and determined the role of sphingolipids level as a novel marker for early detection of human myocardial ischaemic injury. Methods and Results: Venous samples were collected from either the coronary sinus (n = 7) or femoral vein (n = 24) from 31 patients aged 40-73 years-old at 1, 5 min, and 12 h, following elective PCI. Plasma sphingolipids levels were assessed by HPLC. At 1 min coronary sinus levels of sphingosine 1-phosphate (S1P), sphingosine (SPH), and sphinganine (SA) were increased by 314, 115, and 614%, respectively (n = 7), while peripheral blood levels increased by 79, 68, and 272% (n = 24). By 5 min, coronary sinus S1P and SPH levels increased further (720%, 117%), as did peripheral levels of S1P alone (792%). Where troponin T was detectable at 12 h (10 of 31), a strong correlation was found with peak S1P (R (2) = 0.818; P < 0.0001). Conclusion: For the first time, we demonstrate the behavior of plasma sphingolipids following transient cardiac ischaemia in humans. The observation supports the important role of sphingolipids level as a potential novel marker of transient or prolonged myocardial ischaemia. [less ▲]

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See detailActivation of sphingosine-1-phosphate signalling as a potential underlying mechanism of the pleiotropic effects of statin therapy.
Egom, Emmanuel E.; Rose, Robert A.; Neyses, Ludwig UL et al

in Critical reviews in clinical laboratory sciences (2013), 50(3), 79-89

The mechanisms by which statins are beneficial are incompletely understood. While the lowering of low-density lipoprotein concentration is associated with regression of atherosclerosis, the observed ... [more ▼]

The mechanisms by which statins are beneficial are incompletely understood. While the lowering of low-density lipoprotein concentration is associated with regression of atherosclerosis, the observed benefit of statin therapy begins within months after its initiation, making regression an unlikely cause. Although LDL-C lowering is the main mechanism by which statin therapy reduces cardiovascular events, evidence suggests that at least some of the beneficial actions of statins may be mediated by their pleiotropic effects. Thus, statins may modulate the function of cardiovascular cells and key signalling proteins, including small G-proteins, to ultimately exert their pleiotropic effects. Sphingosine-1-phosphate (S1P) is a naturally occurring bioactive lysophospholipid that regulates diverse physiological functions in a variety of different organ systems. Within the cardiovascular system, S1P mediates cardioprotection following ischemia/reperfusion injury, anti-inflammatory response, improvement of endothelial function, increased mobilization and differentiation of endothelial progenitor cells, inhibition of oxidation, and anti-atherogenic and anti-thrombotic actions. Early evidence suggests that the pleiotropic effects of statins may be related to an increase in S1P signalling. This review focuses on S1P signalling as the potential mechanism underlying the pleiotropic effects of statins. An improved understanding of this mechanism may be vital for establishing the clinical relevance of statins and their importance in the treatment and prevention of coronary artery disease. Key points Several studies have demonstrated a benefit from lowering serum LDL-C with statins in patients with and without clinical evidence of CAD. These may be mediated by the pleiotropic effects of statins-the mechanisms of which are incompletely understood. Early evidence suggests that statins may increase S1P signalling pathways through upregulation of the expression of S1P receptors and an increase in plasma levels of S1P to ultimately exert their pleiotropic effects. Future clinical trials and basic science research aimed at the underlying mechanisms of the pleiotropic effects of statins should enlighten us to their relative clinical relevance and importance. [less ▲]

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See detailInfluence of arterial access site selection on outcomes in primary percutaneous coronary intervention: are the results of randomized trials achievable in clinical practice?
Mamas, Mamas A.; Ratib, Karim; Routledge, Helen et al

in JACC. Cardiovascular interventions (2013), 6(7), 698-706

OBJECTIVES: This study sought to investigate the influence of access site utilization on mortality, major adverse cardiac and cardiovascular events (MACCE), bleeding, and vascular complications in a large ... [more ▼]

OBJECTIVES: This study sought to investigate the influence of access site utilization on mortality, major adverse cardiac and cardiovascular events (MACCE), bleeding, and vascular complications in a large number of patients treated by primary percutaneous coronary intervention (PPCI) in the United Kingdom over a 5-year period, through analysis of the British Cardiovascular Intervention Society database. BACKGROUND: Despite advances in antithrombotic and antiplatelet therapy, bleeding complications remain an important cause of morbidity and mortality in patients with acute ST-segment elevation myocardial infarction (STEMI) undergoing PPCI. A significant proportion of such bleeding complications are related to the access site, and adoption of radial access may reduce these complications. These benefits have not previously been studied in a large unselected national population of PPCI patients. METHODS: Mortality (30-day), MACCE (a composite of 30-day mortality and in-hospital myocardial re-infarction, target vessel revascularization, and cerebrovascular events), and bleeding and access site complications were studied based on transfemoral access (TFA) and transradial access (TRA) site utilization in PPCI STEMI patients. The influence of access site selection was studied in 46,128 PPCI patients; TFA was used in 28,091 patients and TRA in 18,037. Data were adjusted for potential confounders using Cox regression that accounted for the propensity to undergo radial or femoral approach. RESULTS: TRA was independently associated with a lower 30-day mortality (hazard ratio [HR]: 0.71, 95% confidence interval [CI]: 0.52 to 0.97; p < 0.05), in-hospital MACCE (HR: 0.73, 95% CI: 0.57 to 0.93; p < 0.05), major bleeding (HR: 0.37, 95% CI: 0.18 to 0.74; p < 0.01), and access site complications (HR: 0.38, 95% CI: 0.19 to 0.75; p < 0.01). CONCLUSIONS: This analysis of a large number of PPCI procedures demonstrates that utilization of TRA is independently associated with major reductions in mortality, MACCE, major bleeding, and vascular complication rates. [less ▲]

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See detailAtrial fibrillation in heart failure: The sword of Damocles revisited.
Khan, Muhammad A.; Ahmed, Fozia; Neyses, Ludwig UL et al

in World Journal of Cardiology (2013), 5(7), 215-27

Heart failure (HF) and atrial fibrillation (AF) frequently coexist and have emerged as major cardiovascular epidemics. There is growing evidence that AF is an independent prognostic marker in HF and ... [more ▼]

Heart failure (HF) and atrial fibrillation (AF) frequently coexist and have emerged as major cardiovascular epidemics. There is growing evidence that AF is an independent prognostic marker in HF and affects patients with both reduced as well as preserved LV systolic function. There has been a general move in clinical practice from a rhythm control to a rate control strategy in HF patients with AF, although recent data suggests that rhythm control strategies may provide better outcomes in selected subgroups of HF patients. Furthermore, various therapeutic modalities including pace and ablate strategies with cardiac resynchronisation or radiofrequency ablation have become increasingly adopted, although their role in the management of AF in patients with HF remains uncertain. This article presents an overview of the multidimensional impact of AF in patients with HF. Relevant literature is highlighted and the effect of various therapeutic modalities on prognosis is discussed. Finally, while novel anticoagulants usher in a new era in thromboprophylaxis, research continues in a variety of new pathways including selective atrial anti-arrhythmic agents and genomic polymorphisms in AF with HF. [less ▲]

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See detailInfluence of access site selection on PCI-related adverse events in patients with STEMI: meta-analysis of randomised controlled trials.
Mamas, Mamas A.; Ratib, Karim; Routledge, Helen et al

in Heart (British Cardiac Society) (2012), 98(4), 303-11

OBJECTIVE: A meta-analysis of all randomised controlled studies that compare outcomes of transradial versus the transfemoral route to better define best practice in patients with ST elevation myocardial ... [more ▼]

OBJECTIVE: A meta-analysis of all randomised controlled studies that compare outcomes of transradial versus the transfemoral route to better define best practice in patients with ST elevation myocardial infarction (STEMI). DESIGN: A Medline and Embase search was conducted using the search terms 'transradial,' 'radial', 'STEMI', 'myocardial' and 'infarction'. SETTING: Randomised controlled studies that compare outcomes of transradial versus the transfemoral route. PATIENTS: A total of nine studies were identified that consisted of 2977 patients with STEMI. Interventions Studies that compare outcomes of transradial versus the transfemoral route. MAIN OUTCOME MEASURES: The primary clinical outcomes of interest were (1) mortality; (2) major adverse cardiac events (MACE); (3) major bleeding and (4) access site complications. RESULTS: Transradial PCI was associated with a reduction in mortality (OR 0.53, 95% CI 0.33 to 0.84; p=0.008), MACE (OR 0.62, 95% CI 0.43 to 0.90; p=0.012), major bleeding events (OR 0.63, 95% CI 0.35-1.12; p=0.12) and access site complications (OR 0.30, 95% CI 0.19 to 0.48; p<0.0001) compared with procedures performed through the femoral route. CONCLUSIONS: This meta-analysis demonstrates a significant reduction in mortality, MACE and major access site complications associated with the transradial access site in STEMI. The meta-analysis supports the preferential use of radial access for STEMI PCI. [less ▲]

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See detailRole of advanced glycation end products in cardiovascular disease.
Hegab, Zeinab; Gibbons, Stephen; Neyses, Ludwig UL et al

in World journal of cardiology (2012), 4(4), 90-102

Advanced glycation end products (AGEs) are produced through the non enzymatic glycation and oxidation of proteins, lipids and nucleic acids. Enhanced formation of AGEs occurs particularly in conditions ... [more ▼]

Advanced glycation end products (AGEs) are produced through the non enzymatic glycation and oxidation of proteins, lipids and nucleic acids. Enhanced formation of AGEs occurs particularly in conditions associated with hyperglycaemia such as diabetes mellitus (DM). AGEs are believed to have a key role in the development and progression of cardiovascular disease in patients with DM through the modification of the structure, function and mechanical properties of tissues through crosslinking intracellular as well as extracellular matrix proteins and through modulating cellular processes through binding to cell surface receptors [receptor for AGEs (RAGE)]. A number of studies have shown a correlation between serum AGE levels and the development and severity of heart failure (HF). Moreover, some studies have suggested that therapies targeted against AGEs may have therapeutic potential in patients with HF. The purpose of this review is to discuss the role of AGEs in cardiovascular disease and in particular in heart failure, focussing on both cellular mechanisms of action as well as highlighting how targeting AGEs may represent a novel therapeutic strategy in the treatment of HF. [less ▲]

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See detailUse of the Sideguard (Cappella) stent in bifurcation lesions: a real-world experience.
Mamas, Mamas A.; Farooq, Vasim; Latib, Azeem et al

in EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology (2012), 7(10), 1170-80

AIMS: The Sideguard(R) stent (Cappella Medical Devices Ltd, Galway, Ireland), is a novel nitinol self-expanding dedicated bifurcation stent that flares proximally at the ostium of the side branch (SB ... [more ▼]

AIMS: The Sideguard(R) stent (Cappella Medical Devices Ltd, Galway, Ireland), is a novel nitinol self-expanding dedicated bifurcation stent that flares proximally at the ostium of the side branch (SB) into a trumpet shape thereby achieving full ostial coverage. The aim of this study is to report the utility and limitations of this stent in patients undergoing treatment to bifurcation coronary lesions in a real-world setting. METHODS AND RESULTS: We prospectively identified 20 successive patients admitted over a 6-month period in whom there was significant SB disease and who were suitable for a bifurcation procedure. The Sideguard(R) stent was successfully used in all 20 cases including several that would have been technically difficult using conventional bifurcation techniques. We highlight use of this system using five illustrative cases that illustrate its utility and limitations in the treatment of bifurcation lesions. CONCLUSIONS: The Sideguard(R) stent can be used to treat complex bifurcation lesions in a straight forward manner and is not subject to the limitations associated with conventional bifurcation PCI techniques including jailing of the SB ostium and inability to fully cover/scaffold the ostium of the SB. [less ▲]

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See detailAutomated workflows for accurate mass-based putative metabolite identification in LC/MS-derived metabolomic datasets.
Brown, Marie; Wedge, David C.; Goodacre, Royston et al

in Bioinformatics (2011), 27(8), 1108-12

MOTIVATION: The study of metabolites (metabolomics) is increasingly being applied to investigate microbial, plant, environmental and mammalian systems. One of the limiting factors is that of chemically ... [more ▼]

MOTIVATION: The study of metabolites (metabolomics) is increasingly being applied to investigate microbial, plant, environmental and mammalian systems. One of the limiting factors is that of chemically identifying metabolites from mass spectrometric signals present in complex datasets. RESULTS: Three workflows have been developed to allow for the rapid, automated and high-throughput annotation and putative metabolite identification of electrospray LC-MS-derived metabolomic datasets. The collection of workflows are defined as PUTMEDID_LCMS and perform feature annotation, matching of accurate m/z to the accurate mass of neutral molecules and associated molecular formula and matching of the molecular formulae to a reference file of metabolites. The software is independent of the instrument and data pre-processing applied. The number of false positives is reduced by eliminating the inaccurate matching of many artifact, isotope, multiply charged and complex adduct peaks through complex interrogation of experimental data. AVAILABILITY: The workflows, standard operating procedure and further information are publicly available at http://www.mcisb.org/resources/putmedid.html. CONTACT: warwick.dunn@manchester.ac.uk. [less ▲]

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See detailLate outcomes of drug eluting and bare metal stents in saphenous vein graft percutaneous coronary intervention.
Nair, Satheesh; Fath-Ordoubadi, Farzin; Clarke, Bernard et al

in EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology (2011), 6(8), 985-91

AIMS: PCI with drug eluting stents (DES) has been shown to reduce restenosis and major adverse cardiac event (MACE) rates compared to bare metal stents (BMS) in native coronary vessels, although outcomes ... [more ▼]

AIMS: PCI with drug eluting stents (DES) has been shown to reduce restenosis and major adverse cardiac event (MACE) rates compared to bare metal stents (BMS) in native coronary vessels, although outcomes in saphenous vein graft (SVG) lesions are less clear. We retrospectively studied 388 consecutive patients admitted to our centre for SVG PCI to assess mortality and MACE outcomes (defined as composite endpoint of all-death, stroke, myocardial infarction, stent thrombosis and target lesion (TLR)/vessel (TVR) revascularisation) associated with BMS and DES use. METHODS AND RESULTS: Two hundred and nineteen (219) patients had BMS and 169 had DES (total 388 patients). Mean follow up was 41.9+/-23.5 months. No significant differences were observed in mortality (14.2% vs. 11.8%) or MACE (37.6% vs. 35.8%) between the BMS and DES groups at four years follow-up or at other intervening time points studied. Similarly, no differences in TVR/TLR rates were observed over a similar time period (19.8% vs. 21.6%). CONCLUSIONS: We have observed that DES and BMS use in SVG PCI have comparable mortality and MACE rates, and that in contrast to PCI in native coronary arteries, DES do not reduce revascularisation rates in our study cohort. [less ▲]

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See detailA comparison of drug-eluting stents versus bare metal stents in saphenous vein graft PCI outcomes: a meta-analysis.
Mamas, Mamas A.; Foley, James; Nair, Satheesh et al

in Journal of interventional cardiology (2011), 24(2), 172-80

AIMS: Studies demonstrate that percutaneous coronary intervention (PCI) with drug-eluting stents (DES) is associated with reduced revascularization and major adverse cardiac events (MACE) rates compared ... [more ▼]

AIMS: Studies demonstrate that percutaneous coronary intervention (PCI) with drug-eluting stents (DES) is associated with reduced revascularization and major adverse cardiac events (MACE) rates compared to bare metal stents (BMS) in native coronary vessels. Optimal PCI treatment of saphenous vein graft (SVG) lesions remains unclear despite SVG procedures representing up to 10% of PCI cases. We therefore performed a meta-analysis to compare outcomes between BMS and DES in SVG PCI. METHODS AND RESULTS: A search (2004-2009) of MEDLINE and conference proceedings for all relevant studies comparing mortality and MACE outcomes in DES versus BMS in SVG PCI and meta-analysis of the data was performed. Twenty studies were identified from 2005 to 2009 enrolling a total of 5,296 patients. Meta-analysis revealed a decrease in mortality associated with DES use, odds ratio (OR) 0.68; 95% confidence interval (CI) 0.53-0.88; P = 0.004. Similarly, MACE (OR 0.64; 95% CI 0.51-0.82; P < 0.001), total lesion revascularization (OR 0.60; 95% CI 0.43-0.83; P = 0.002), and total vessel revascularization (OR 0.57; 95% CI 0.41-0.80; P = 0.001) were significantly decreased in the patients in which DES were used compared to BMS. This reduction in mortality and MACE events associated with DES use appears to be limited to registry studies and not randomized controlled studies. CONCLUSIONS: Our meta-analysis suggests DES use to be safe in SVG PCI and associated with reduced mortality and MACE rates with reductions in revascularization also observed. [less ▲]

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See detailWhat are the thromboembolic risks of heart failure combined with chronic or paroxysmal AF?
Caldwell, Jane Cochrane; Mamas, Mamas A.; Neyses, Ludwig UL et al

in Journal of cardiac failure (2010), 16(4), 340-7

BACKGROUND: Heart failure (HF) and atrial fibrillation (AF) are common disorders that frequently occur together and are associated with an increased risk of thromboembolism. This thromboembolic risk may ... [more ▼]

BACKGROUND: Heart failure (HF) and atrial fibrillation (AF) are common disorders that frequently occur together and are associated with an increased risk of thromboembolism. This thromboembolic risk may be reduced by anticoagulation with warfarin but not without introducing new hemorrhagic risks. METHODS AND RESULTS: Current guidelines recommend the use of anticoagulation in patients with HF and chronic AF and paroxysmal AF (PAF) that is symptomatic or frequent and prolonged enough to be detected by electrocardiogram. However, the evidence supporting these recommendations is weak and does not take account of research indicating that the prothrombotic risk is higher in more severe HF. CONCLUSIONS: An area not addressed by current guidelines is anticoagulation in patients with HF and short, asymptomatic episodes of AF. These issues need to be resolved with further studies using implanted devices to detect such asymptomatic PAF. [less ▲]

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See detailImpaired glucose tolerance and insulin resistance in heart failure: underrecognized and undertreated?
Mamas, Mamas A.; Deaton, Christi; Rutter, Martin K. et al

in Journal of cardiac failure (2010), 16(9), 761-8

BACKGROUND: A link between diabetes mellitus (DM) and heart failure (HF) has been well-recognized for more than a century. HF is also closely linked to abnormal glucose regulation (AGR) and insulin ... [more ▼]

BACKGROUND: A link between diabetes mellitus (DM) and heart failure (HF) has been well-recognized for more than a century. HF is also closely linked to abnormal glucose regulation (AGR) and insulin resistance (IR) in patients without DM and, similarly, these conditions commonly coexist. In epidemiological studies, each condition appears to predict the other. The prevalence of AGR/IR in HF patients without DM is significantly underrecognized and, as yet, the optimal method for screening for these abnormalities in the outpatient setting is unclear. METHODS AND RESULTS: The purpose of this review is to overview the prevalence and prognostic impact of AGR and IR in HF patients without DM and discuss potential pathophysiological pathways that link these conditions with HF. The severity of glucose intolerance in patients with HF correlates with functional and clinical severity of HF and is an independent predictor of an adverse outcome. It is thought that changes in cardiac metabolism, including a switch from glucose metabolism toward fatty acid metabolism, may in part contribute to the pathophysiological processes associated with HF patients with AGR/IR. CONCLUSIONS: We discuss how pharmacological targeting of metabolic pathways in the myocardium of these patients with HF may represent novel therapeutic strategies in these at-risk patients. [less ▲]

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See detailResting Pd/Pa measured with intracoronary pressure wire strongly predicts fractional flow reserve.
Mamas, Mamas A.; Horner, Simon; Welch, Elise et al

in The Journal of invasive cardiology (2010), 22(6), 260-5

OBJECTIVE: To investigate the relationship between resting distal coronary pressure to aortic pressure ratio (Pd/Pa) and fractional flow reserve (FFR) obtained during maximal hyperemia. BACKGROUND: FFR is ... [more ▼]

OBJECTIVE: To investigate the relationship between resting distal coronary pressure to aortic pressure ratio (Pd/Pa) and fractional flow reserve (FFR) obtained during maximal hyperemia. BACKGROUND: FFR is an invasive index of the functional severity of a coronary artery stenosis determined from coronary pressure measurements. It is generally believed that there is little correlation between resting Pd/Pa and FFR obtained during maximal hyperemia. We have therefore studied this relationship in a large cohort of patients who had undergone pressure- wire assessments. METHODS: 528 consecutive pressure-wire studies performed in 483 patients over a 2-year period were retrospectively analyzed. RESULTS: A linear correlation between resting Pd/Pa and FFR post-pharmacological hyperemia was observed (rho = 0.74; p < 0.0001). When a FFR of < or = 0.75 (or < or = 0.80 as per FAME) was defined as positive, a resting Pd/Pa of < or = 0.85 (< or = 0.87) had a positive predictive value (PPV) of 95% (94.6%), while a resting Pd/Pa of > or = 0.93 (> or = 0.96) had a negative predictive value (NPV) of 95.7% (93%). CONCLUSIONS: We demonstrate a strong correlation between resting Pd/Pa and FFR. Resting values of Pd/Pa can be used to predict a positive FFR result with relatively high PPV and NPV. This may potentially obviate the need for adenosine infusion in a proportion of pressure-wire studies. [less ▲]

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See detailA meta-analysis of glucose-insulin-potassium therapy for treatment of acute myocardial infarction.
Mamas, Mamas A.; Neyses, Ludwig UL; Fath-Ordoubadi, Farzin

in Experimental & Clinical Cardiology (2010), 15(2), 20-4

BACKGROUND: Glucose-insulin-potassium (GIK) therapy has been proposed to provide metabolic support to ischemic myocardium. A meta-analysis that included 1932 patients performed 10 years previously ... [more ▼]

BACKGROUND: Glucose-insulin-potassium (GIK) therapy has been proposed to provide metabolic support to ischemic myocardium. A meta-analysis that included 1932 patients performed 10 years previously demonstrated that GIK therapy may have an important role in reducing mortality after acute myocardial infarction (AMI). Since then, many larger randomized trials investigating the role of GIK in the setting of AMI have been published; hence, the present study repeats the previous meta-analysis performed by the current authors to include these trials. METHOD AND RESULTS: A systematic MEDLINE search for all randomized, placebo-controlled studies of GIK therapy in the setting of AMI was conducted and a meta-analysis of the mortality data was performed. A total of 16 randomized trials from 1966 to 2008 were identified, with 28,374 patients included in the current meta-analysis. There was a total of 1367 deaths (9.6%) in the GIK group, with 1351 deaths (9.6%) in the control group. Meta-analysis did not reveal any benefit from GIK treatment (OR 1.0; 95% CI 0.9 to 1.1; P=0.9). Subgroup analysis of patients given high-dose GIK and in patients in whom reperfusion was not obtained did not demonstrate a benefit from GIK therapy. CONCLUSION: A meta-analysis of 16 randomized trials that spanned 40 years and involved more than 28,000 patients did not reveal any mortality benefit for ST segment elevation AMI using GIK therapy when data from the modern thrombolysis/primary percutaneous coronary intervention era were included. [less ▲]

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See detailUse of the Heartrail II catheter as a distal stent delivery device; an extended case series.
Mamas, Mamas A.; Eichhofer, Jonas; Hendry, Cara et al

in EuroIntervention : journal of EuroPCR in collaboration with the Working Group on Interventional Cardiology of the European Society of Cardiology (2009), 5(2), 265-71

AIMS: The Terumo Heartrail catheter (Terumo Corp., Tokyo, Japan) allows extra deep catheter intubation of coronary vessels and has been shown to be useful in CTO lesions. The aim of this study is to ... [more ▼]

AIMS: The Terumo Heartrail catheter (Terumo Corp., Tokyo, Japan) allows extra deep catheter intubation of coronary vessels and has been shown to be useful in CTO lesions. The aim of this study is to assess the safety and efficacy of using the Heartrail II catheter as a distal stent delivery system in PCI following failure of conventional techniques. METHODS AND RESULTS: We prospectively identified cases performed over a 15-month period in which a Heartrail catheter was used to facilitate stent delivery following failure of conventional techniques. Stent delivery using the Heartrail catheter was performed in 35 cases and was successful in 31 cases. Success rates of 100% in grafts, 95% in RCA, 80% in LAD and 60% in circumflex cases were recorded respectively. Successful stent delivery was associated with intubation depth, with 29/29 succeeding when the intubation depth was > 2 cm and failure in 4/5 cases when the intubation depth <or= 2 cm. There were no complications related to deep intubation of the catheter. CONCLUSIONS: Use of the Heartrail catheter is safe and highly effective for aiding stent delivery across proximal obstructions in both left and right coronary systems. The small number of unsuccessful cases were related to inability of the catheter to traverse stenotic proximal obstructions within 2 cm of the RCA and LCA origins. [less ▲]

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See detailA meta-analysis of the prognostic significance of atrial fibrillation in chronic heart failure.
Mamas, Mamas A.; Caldwell, Jane C.; Chacko, Sanoj et al

in European journal of heart failure (2009), 11(7), 676-83

AIMS: Atrial fibrillation (AF) is one of the commonest sustained arrhythmias in chronic heart failure (CHF), although the prognostic implications of the presence of AF in CHF remain controversial. We have ... [more ▼]

AIMS: Atrial fibrillation (AF) is one of the commonest sustained arrhythmias in chronic heart failure (CHF), although the prognostic implications of the presence of AF in CHF remain controversial. We have therefore performed this meta-analysis to study the effects of the presence of AF on mortality in CHF patients. METHODS AND RESULTS: A systematic MEDLINE search for all randomized trials and observational studies in which the influence of AF on CHF mortality was investigated and meta-analysis of the mortality data was performed. A total of 16 studies were identified of which 7 were randomized trials and 9 were observational studies including 30,248 and 23,721 patients, respectively. An adjusted meta-analysis of the data revealed that the presence of AF is associated with an adverse effect on total mortality with an odds ratio (OR) of 1.40 [95% confidence interval (CI) 1.32-1.48, P < 0.0001] in randomized trials and an OR of 1.14 (95% CI 1.03-1.26, P < 0.05) in observational studies. This increase in mortality associated with the presence of AF was observed in subgroups of CHF patients with both preserved and impaired left ventricular (LV) systolic function. CONCLUSION: In conclusion, meta-analysis of 16 studies involving 53,969 patients suggests that the presence of AF is associated with an adverse prognosis in CHF irrespective of LV systolic function. [less ▲]

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See detailAtrial fibrillation is under-recognized in chronic heart failure: insights from a heart failure cohort treated with cardiac resynchronization therapy.
Caldwell, Jane C.; Contractor, Hussain; Petkar, Sanjiv et al

in Europace : European pacing, arrhythmias, and cardiac electrophysiology : journal of the working groups on cardiac pacing, arrhythmias, and cardiac cellular electrophysiology of the European Society of Cardiology (2009), 11(10), 1295-300

AIMS: Atrial fibrillation (AF) is the most common sustained arrhythmia in patients with chronic heart failure (CHF). Under-detection of asymptomatic paroxysmal AF (PAF) underestimates the true burden of ... [more ▼]

AIMS: Atrial fibrillation (AF) is the most common sustained arrhythmia in patients with chronic heart failure (CHF). Under-detection of asymptomatic paroxysmal AF (PAF) underestimates the true burden of AF in patients with CHF. We retrospectively studied the prevalence of asymptomatic PAF in 162 CHF patients through analysis of cardiac resynchronization therapy (CRT) device downloads to determine whether these episodes are associated with adverse outcomes. METHODS AND RESULTS: An episode of AF was defined by mode switching on CRT devices with an atrial rate >200 for at least 30 s. Of the 101 patients thought to be persistently in sinus rhythm (SR), 27% were found to have significant paroxysms of AF, with the cumulative percentage of time in the 'mode-switch mode' (i.e. the AF burden) of 1.6 +/- 0.9%. Mortality was 19.2% in patients with newly identified PAF with hospitalization and thrombo-embolism rates of 42.3 and 2.1%, respectively, compared with mortality of 10.4% with hospitalization and thrombo-embolism rates of 41.8 and 1.9%, respectively, in patients persistently in SR (P= NS). CONCLUSION: Analysis of data from CRT devices in a population of CHF patients with severe left ventricular dysfunction shows that a significant proportion of those perceived to be persistently in SR have undiagnosed paroxysms of AF but with relatively low burden. These episodes appear to be associated with a trend towards increased mortality but no effects on hospitalization or thrombo-embolism rates. [less ▲]

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See detailTargeting the sarcolemmal calcium pump: a potential novel strategy for the treatment of cardiovascular disease.
Oceandy, Delvac; Mamas, Mamas A.; Neyses, Ludwig UL

in Cardiovascular & hematological agents in medicinal chemistry (2007), 5(4), 300-4

Intracellular calcium dynamics play a very important role in mediating contraction and signalling in cardiomyocytes and vascular smooth muscle cells. A number of calcium transporters have been identified ... [more ▼]

Intracellular calcium dynamics play a very important role in mediating contraction and signalling in cardiomyocytes and vascular smooth muscle cells. A number of calcium transporters have been identified that orchestrate a complex process of excitation-contraction coupling and molecular signalling. Despite the variability of the calcium transporters expressed in cardiomyocytes, most calcium channel blockers used therapeutically target the L-type calcium channel and exhibit antihypertensive and/or vasodilating activities. Recently, another calcium pump which is located in the sarcolemma has been shown to mediate cardiac contractility and vascular tone. Interestingly, this sarcolemmal calcium pump (also known as Plasma Membrane Calcium/calmodulin dependent ATPase or PMCA) exerts its function not by altering global calcium concentration, but by mediating signal transduction pathways. This review will discuss recent advances that support the key roles of PMCA as signalling molecule and the potential to target this calcium pump as a novel approach for the treatment of cardiovascular disease. [less ▲]

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