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Dive into the research topics where Douglas G. Fraser is active.

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Featured researches published by Douglas G. Fraser.


Heart | 2012

Influence of access site selection on PCI-related adverse events in patients with STEMI: meta-analysis of randomised controlled trials

Mamas A. Mamas; Karim Ratib; Helen Routledge; Farzin Fath-Ordoubadi; Ludwig Neyses; Yves Louvard; Douglas G. Fraser; James Nolan

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.


Eurointervention | 2012

Longitudinal stent deformation: a retrospective analysis of frequency and mechanisms.

Paul Williams; Mamas A. Mamas; Kenneth P. Morgan; Magdi El-Omar; Bernard Clarke; Anthony Bainbridge; Farzin Fath-Ordoubadi; Douglas G. Fraser

AIMS Modern drug-eluting stents are constructed with thin struts and are easy to deliver and highly conformable. However, although innovative designs have enabled maintenance of radial strength, longitudinal strength may be lower with these stents and there have been recent reports of longitudinal stent compression of ostially deployed stents. We report the experience in our centre on longitudinal stent deformation and explore mechanisms of this complication and its frequency with various drug-eluting stent platforms. METHODS AND RESULTS Nine cases of longitudinal stent deformation were identified over a four year period representing 0.2% of cases and affected 0.097% of stents deployed. There were several mechanisms for this complication including compression by post-dilatation balloons, guide catheter extensions and proximal embolic protection devices. The rate of stent deformation varied from 0% in several stent types to 0.86% in the case of the Promus Element stent. There was one case of late stent thrombosis attributable to longitudinal stent deformation. CONCLUSIONS Longitudinal stent deformation can occur secondary to a variety of mechanisms and identification is important as, left untreated, it may be associated with a risk of stent thrombosis. Although seen with several different stents, in our series it was more commonly observed with the Promus Element stent.


Catheterization and Cardiovascular Interventions | 2009

Use of the sheathless guide catheter during routine transradial percutaneous coronary intervention: a feasibility study.

Mamas A. Mamas; Savio D'Souza; Cara Hendry; Razwan Ali; Heather Iles-Smith; Karen Palmer; Magdi El-Omar; Farzin Fath-Ordoubadi; Ludwig Neyses; Douglas G. Fraser

Objective: The aim of this study is to investigate the feasibility of using a 6.5 Fr sheathless guide catheter as a default system in transradial (TRA) percutaneous coronary intervention (PCI). Background: TRA PCI has been shown to reduce mortality rates through a reduction in access site related bleeding complications compared with procedures performed though a femoral approach. Complications associated with the TRA route increase with the size of sheath used. These complications may be reduced by the use of a sheathless guide catheter system (Asahi Intecc, Japan) that is 1–2 Fr sizes smaller in diameter than the corresponding introducer sheath. Methods: We performed PCI in 100 consecutive cases using 6.5 Fr sheathless guides to determine the procedural success, rates of symptomatic radial spasm and radial occlusion. Results: Procedural success using the 6.5 Fr sheathless guide catheter system was 100% with no cases requiring conversion to a conventional guide and catheter system. There were no procedural complications recorded associated with the use of the catheter. Adjunctive devices used in this cohort included IVUS, stent delivery catheters, distal protection devices, and simple thrombectomy catheters. The rate of radial spasm was 5% and the rate of radial occlusion at 2 months was 2%. Conclusion: Use of the 6.5 Fr sheathless guide catheter system, which has an outer diameter <5 Fr sheath, as the default system in routine PCI is feasible with a high rate of procedural success via the radial artery.


Jacc-cardiovascular Interventions | 2013

Influence of Arterial Access Site Selection on Outcomes in Primary Percutaneous Coronary Intervention : Are the Results of Randomized Trials Achievable in Clinical Practice?

Mamas A. Mamas; Karim Ratib; Helen Routledge; Ludwig Neyses; Douglas G. Fraser; Mark A. de Belder; Peter Ludman; James Nolan

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.


Catheterization and Cardiovascular Interventions | 2010

Distal Stent Delivery With Guideliner Catheter: First in Man Experience

Mamas A. Mamas; Farzin Fath-Ordoubadi; Douglas G. Fraser

Failure to deliver stents is one of the commonest causes of procedural failure in contemporary PCI practice. We describe successful use of the Guideliner Catheter, the first purpose designed FDA and CE marked device delivery catheter in 13 complex cases in native coronary vessels and bypass grafts performed via the radial route to enable distal stent delivery following failure of conventional techniques. We discuss how the Guideliner catheter may be used to facilitate difficult radial cases.


Jacc-cardiovascular Interventions | 2015

Access Site Practice And Procedural Outcomes In Relation To Clinical Presentation In 439,947 Patients Undergoing Percutaneous Coronary Intervention In The United Kingdom

Karim Ratib; Mamas A. Mamas; Simon G. Anderson; Gurbir Bhatia; Helen Routledge; Mark A. de Belder; Peter Ludman; Douglas G. Fraser; James Nolan

OBJECTIVES This study sought to determine the relationships among access site practice, clinical presentation, and procedural outcomes in a large patient population. BACKGROUND Transradial access (TRA) has been associated with improved patient outcomes in selected populations in randomized trials. It is unclear whether these outcomes are achievable in clinical practice. METHODS Using the BCIS (British Cardiovascular Intervention Society) database, we investigated outcomes for percutaneous coronary intervention procedures undertaken between 2007 and 2012 according to access site practice. Patients were categorized as stable, non-ST-segment elevation acute coronary syndrome (NSTEACS) and ST-elevation acute coronary syndrome (STEACS). The impact of access site on 30-day mortality, major adverse cardiac events, bleeding, and arterial access site complications was studied. RESULTS Data from 210,260 TRA and 229,687 transfemoral access procedures were analyzed. Following multivariate analysis, TRA was independently associated with a reduction in bleeding in all presenting syndromes (stable odds ratio [OR]: 0.24, p < 0.001; NSTEACS OR: 0.35, p < 0.001; STEACS OR: 0.47, p < 0.001) as well as access site complications (stable OR: 0.21, p < 0.001; NSTEACS OR: 0.19; STEACS OR: 0.16, p < 0.001). TRA was associated with reduced major adverse cardiac events only in patients with unstable syndromes (stable OR: 1.08, p = 0.25; NSTEACS OR: 0.72, p < 0.001; STEACS OR: 0.70, p < 0.001). TRA was associated with improved outcomes compared with a transfemoral access (TFA) with a vascular closure device in a propensity matched cohort. CONCLUSIONS In this large study, TRA is associated with reduced percutaneous coronary intervention-related complications in all patient groups and may reduce major adverse cardiac events and mortality in ACS patients. TRA is superior to transfemoral access with closure devices. Use of TRA may lead to important patient benefits in routine practice. TRA should be considered the preferred access site for percutaneous coronary intervention.


Journal of the American College of Cardiology | 2013

Baseline Bleeding Risk and Arterial Access Site Practice in Relation to Procedural Outcomes After Percutaneous Coronary Intervention

Mamas A. Mamas; Simon G. Anderson; Matthew Carr; Karim Ratib; Iain Buchan; Alex Sirker; Douglas G. Fraser; David Hildick-Smith; Mark A. de Belder; Peter Ludman; James Nolan

BACKGROUND Transradial access (TRA) has been associated with reduced access site-related bleeding complications and mortality after percutaneous coronary intervention (PCI). It is unclear, however, whether these observed benefits are influenced by baseline bleeding risk. OBJECTIVES This study investigated the relationship between baseline bleeding risk, TRA utilization, and procedure-related outcomes in patients undergoing PCI enrolled in the British Cardiovascular Intervention Society database. METHODS Baseline bleeding risk was calculated by using modified Mehran bleeding risk scores in 348,689 PCI procedures performed between 2006 and 2011. Four categories for bleeding risk were defined for the modified Mehran risk score (MMRS): low (<10), moderate (10 to 14), high (15 to 19), and very high (≥20). The impact of baseline bleeding risk on 30-day mortality and its relationship with access site were studied. RESULTS TRA was independently associated with a 35% reduction in 30-day mortality risk (odds ratio [OR]: 0.65 [95% confidence interval (CI): 0.59 to 0.72]; p < 0.0001), with the magnitude of mortality reduction related to baseline bleeding risk (MMRS <10, OR: 0.73 [95% CI: 0.62 to 0.86]; MMRS ≥20, OR: 0.53 [95% CI: 0.47 to 0.61]). In patients with an MMRS <10, TRA was used in 71,771 (43.2%) of 166,083 PCI procedures; TRA was used in 8,655 (40.1%) of 21,559 PCI procedures in patients with an MMRS ≥20, illustrating that TRA was used less in those at highest risk from bleeding complications (p < 0.0001). CONCLUSIONS TRA was independently associated with reduced 30-day mortality, and the magnitude of this effect was related to baseline bleeding risk; those at highest risk of bleeding complications gained the greatest benefit from adoption of TRA during PCI.


Catheterization and Cardiovascular Interventions | 2008

Atraumatic complex transradial intervention using large bore sheathless guide catheter.

Mamas A. Mamas; Farzin Fath-Ordoubadi; Douglas G. Fraser

The Asahi sheathless guide catheter system is a hydrophilic catheter with a central dilator that does not require an introducer sheath during transradial percutaneous coronary intervention. Conventional sheath introducers are often 1- to 2F larger than the catheter itself; therefore, this system enables the use of a larger French catheter during procedures than would otherwise be possible using conventional techniques. We describe the use of a 7.5F sheathless guide catheter system with a smaller outer diameter than a conventional 6F introducer sheath in 16 cases performed transradially involving rotablation, crush stent bifurcation lesions, 7F proximal protection, and thrombectomy devices. Such cases would otherwise not always be possible if performed using conventional transradial techniques in patients with smaller radial artery sizes.


Catheterization and Cardiovascular Interventions | 2003

Hydrophilic coating aids radial sheath withdrawal and reduces patient discomfort following transradial coronary intervention: A randomized double-blind comparison of coated and uncoated sheaths

Ferdinand Kiemeneij; Douglas G. Fraser; Ton Slagboom; GertJan Laarman; Ron van der Wieken

Radial artery spasm may cause severe discomfort during radial artery sheath removal. A hydrophilic‐coated sheath may reduce the force required to remove a radial sheath. This force may be quantified using an automatic pullback device (APD). The objective of this study was to assess if a hydrophilic coating reduces the required force and discomfort associated with removal of a radial sheath following transradial coronary intervention. Ninety patients undergoing percutaneous coronary intervention via the radial artery were randomly assigned to two groups receiving either coated or uncoated introducer sheaths. Radifocus Introducer II (Terumo) 25 cm, 6 Fr radial sheaths and sheaths that were identical apart from the presence of the coating were used in all patients. The APD was used for sheath removal at the end of the procedure. Three patients (7%) in the coated group experienced discomfort during automatic sheath removal, compared to 12 patients (27%) in the uncoated group (P = 0.02). The maximum pullback force (MPF) was significantly lower in the coated compared to the uncoated group (0.24 ± 0.31 vs. 0.44 ± 0.33 kg; P = 0.003). Similarly, the mean pullback force was significantly lower in the coated group (0.14 ± 0.23 vs. 0.32 ± 0.24 kg; P < 0.001). Only one patient (2%) in each group had an MPF greater than 1.0 kg together with clinical evidence of radial artery spasm. Removal of the coated Terumo Radifocus sheath requires less force than an identical uncoated sheath. The coated sheath was also associated with less discomfort for the patient. Cathet Cardiovasc Intervent 2003;59:161–164.


American Heart Journal | 2013

Influence of access site choice on incidence of neurologic complications after percutaneous coronary intervention.

Karim Ratib; Mamas A. Mamas; Helen Routledge; Peter Ludman; Douglas G. Fraser; James Nolan

BACKGROUND Neurologic complications (NCs) are a rare but potentially devastating complication that may follow percutaneous coronary intervention (PCI). In recent years, there has been an increase in use of transradial access, driven by a developing body of evidence that favors its use over femoral access. Concerns have been raised, however, that transradial access may increase the risk of NC compared with transfemoral access. We aimed to investigate the influence of access site selection on the occurrence of NCs through a period of transition during which transradial access became the dominant route for PCI procedures performed in the United Kingdom. METHODS We performed a retrospective analysis of the British Cardiovascular Intervention Society database between January 2006 and December 2010. The data were split into 2 cohorts based on access site. An NC was defined as a periprocedural ischemic stroke, hemorrhagic stroke, or transient ischemic attack occurring before hospital discharge. Binary logistic multivariate analysis was used to investigate the influence of access site utilization on NCs and adjust for measured confounding factors. RESULTS Between 2006 and 2010, the use of radial access increased from 17.2% to 50.8% of all PCI procedures. A total of 124,616 radial procedures and 223,476 femoral procedures were studied with a NC rate of 0.11% in each cohort. In univariate (odds ratio 1.01, 95% CI 0.82-1.24, P = .93) and multivariate analysis (odds ratio 0.99, 95% CI 0.79-1.23, P = .91), there was no significant association between the use of radial access and the occurrence of NCs. CONCLUSION These results suggest that radial access is not associated with an increased risk of clinically detected NCs, even during a period when there was a rapid evolution in the preferred access site for PCI in the United Kingdom. These are reassuring results, particularly for operators embarking on a change to radial access for PCI.

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Magdi El-Omar

Manchester Royal Infirmary

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Ludwig Neyses

University of Luxembourg

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Bernard Clarke

Manchester Royal Infirmary

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Paul D. Williams

James Cook University Hospital

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Peter Ludman

Queen Elizabeth Hospital Birmingham

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Rajdeep Khattar

National Institutes of Health

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Samer Arnous

Manchester Royal Infirmary

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