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Dive into the research topics where John L. Morris is active.

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Featured researches published by John L. Morris.


The Lancet | 2014

Unfractionated heparin versus bivalirudin in primary percutaneous coronary intervention (HEAT-PPCI): an open-label, single centre, randomised controlled trial

Adeel Shahzad; Ian Kemp; Christine Mars; Keith S. Wilson; Claire Roome; Rob Cooper; Mohammed Andron; Clare Appleby; Mike Fisher; Aleem Khand; Babu Kunadian; Joseph D. Mills; John L. Morris; Wl Morrison; Shahzad Munir; Nick D. Palmer; Raphael A. Perry; David R. Ramsdale; Periaswamy Velavan; Rod Stables

BACKGROUND Bivalirudin, with selective use of glycoprotein (GP) IIb/IIIa inhibitor agents, is an accepted standard of care in primary percutaneous coronary intervention (PPCI). We aimed to compare antithrombotic therapy with bivalirudin or unfractionated heparin during this procedure. METHODS In our open-label, randomised controlled trial, we enrolled consecutive adults scheduled for angiography in the context of a PPCI presentation at Liverpool Heart and Chest Hospital (Liverpool, UK) with a strategy of delayed consent. Before angiography, we randomly allocated patients (1:1; stratified by age [<75 years vs ≥75 years] and presence of cardiogenic shock [yes vs no]) to heparin (70 U/kg) or bivalirudin (bolus 0·75 mg/kg; infusion 1·75 mg/kg per h). Patients were followed up for 28 days. The primary efficacy outcome was a composite of all-cause mortality, cerebrovascular accident, reinfarction, or unplanned target lesion revascularisation. The primary safety outcome was incidence of major bleeding (type 3-5 as per Bleeding Academic Research Consortium definitions). This study is registered with ClinicalTrials.gov, number NCT01519518. FINDINGS Between Feb 7, 2012, and Nov 20, 2013, 1829 of 1917 patients undergoing emergency angiography at our centre (representing 97% of trial-naive presentations) were randomly allocated treatment, with 1812 included in the final analyses. 751 (83%) of 905 patients in the bivalirudin group and 740 (82%) of 907 patients in the heparin group had a percutaneous coronary intervention. The rate of GP IIb/IIIa inhibitor use was much the same between groups (122 patients [13%] in the bivalirudin group and 140 patients [15%] in the heparin group). The primary efficacy outcome occurred in 79 (8·7%) of 905 patients in the bivalirudin group and 52 (5·7%) of 907 patients in the heparin group (absolute risk difference 3·0%; relative risk [RR] 1·52, 95% CI 1·09-2·13, p=0·01). The primary safety outcome occurred in 32 (3·5%) of 905 patients in the bivalirudin group and 28 (3·1%) of 907 patients in the heparin group (0·4%; 1·15, 0·70-1·89, p=0·59). INTERPRETATION Compared with bivalirudin, heparin reduces the incidence of major adverse ischaemic events in the setting of PPCI, with no increase in bleeding complications. Systematic use of heparin rather than bivalirudin would reduce drug costs substantially. FUNDING Liverpool Heart and Chest Hospital, UK National Institute of Health Research, The Medicines Company, AstraZeneca, The Bentley Drivers Club (UK).


Jacc-cardiovascular Interventions | 2010

Impact of length and hydrophilic coating of the introducer sheath on radial artery spasm during transradial coronary intervention: a randomized study.

Sudhir Rathore; Rodney H. Stables; Maheshwar Pauriah; Abdul Hakeem; Joseph D. Mills; Nick D. Palmer; Raphael A. Perry; John L. Morris

OBJECTIVES The aim of this study was to assess the impact of length and hydrophilic coating of the introducer sheath on radial artery spasm, radial artery occlusion, and local vascular complications in patients undergoing transradial coronary procedures. BACKGROUND Radial artery spasm is common during transradial procedures and the most common cause for procedural failure. METHODS We randomly assigned, in a factorial design, 790 patients scheduled for a transradial coronary procedure to long (23-cm) or short (13-cm) and hydrophilic-coated or uncoated introducer sheaths. The primary outcome measure was clinical evidence of radial artery spasm, and secondary outcome measures were patient discomfort and local vascular complications. RESULTS Procedural success was achieved in 96% of the cases, and radial artery spasm accounted for 17 of 33 failed cases. There was significantly less radial artery spasm (19.0% vs. 39.9%, odds ratio [OR]: 2.87; 95% confidence interval [CI]: 2.07 to 3.97, p < 0.001) and patient reported discomfort (15.1% vs. 28.5%, OR: 2.27; 95% CI: 1.59 to 3.23, p < 0.001) in patients receiving a hydrophilic-coated sheath. No difference was observed between long and short sheaths. Radial artery occlusion was observed in 9.5% of the patients and was not influenced by sheath length or coating. A local large hematoma or arterial dissection was seen in 2.6% of the patients with no difference in groups allocated at randomization. Younger age, female sex, diabetes, and lower body mass index were identified as independent predictors of radial artery spasm. CONCLUSIONS Hydrophilic sheath coating, but not sheath length, reduces the incidence of radial artery spasm during transradial coronary procedures.


Catheterization and Cardiovascular Interventions | 2009

A comparison of the transradial and the transfemoral approach in chronic total occlusion percutaneous coronary intervention

Sudhir Rathore; Abdul Hakeem; Maheshwar Pauriah; Elved Roberts; Andrew Beaumont; John L. Morris

Background: Transradial coronary intervention is a safe and effective method of percutaneous revascularization. Furthermore, the indications for transradial percutaneous coronary intervention (PCI) are expanding. However, there is limited data on the efficacy and the safety of the transradial approach for chronic total occlusion (CTO) PCI. Methods: We examined 468 patients who underwent CTO PCI between January 2003 and December 2005, and compared the radial (318 patients) and the femoral (150 patients) approach. Results: Baseline demographics, lesion location, and the vessel treated were similar in both groups. Angiographic success was 82% in radial versus 86% in femoral group, P = 0.28, similar in both groups. Total fluoroscopy time (24.49 ± 13.18 vs. 24.07 ± 14.12 min, P = 0.36), total procedure time (54.22 ± 25.35 vs. 60.23 ± 28.15 min, P = 0.23), and the use of total contrast volume (395.54 ± 180.25 vs. 406.15 ± 173.98 ml, P = 0.27) were similar in radial and femoral group, respectively. In hospital MACE [radial: 12 MI (3.8%) vs. femoral: 1 death (0.7%) and 5 MI (3.5%), P = 0.26] were similar in both groups. Access site vascular complications [radial: 11 (3.5%) vs. femoral: 17 (11.3%), P ≤ 0.001] were significantly less in radial group. Conclusions: The radial approach in CTO PCI is as fast and successful as the femoral approach with comparable in hospital MACE. However, there are far less access site complications with radial approach.


Catheterization and Cardiovascular Interventions | 2010

A randomized comparison of TR band and radistop hemostatic compression devices after transradial coronary intervention

Sudhir Rathore; Rodney H. Stables; Maheshwar Pauriah; Abdul Hakeem; Joseph D. Mills; Nick D. Palmer; Raphael A. Perry; John L. Morris

Background: The transradial route for coronary intervention has proven to be safe, effective, and widely applicable in different clinical situations. Several compressive hemostatic devices have been introduced that have shown to be safe and are effective in achieving hemostasis. Methods: Seven hundred ninety patients were randomly assigned to receive either TR band or Radistop hemostatic compression devices after transradial coronary procedure. The outcome measures were patient tolerance of the device, local vascular complications, and the time taken to achieve hemostasis. Results: The mean age was 62.88 years, and 74.2% of the patients were men. Patient age, height, weight, wrist circumference, body mass index, male sex, hypertension, diabetes, hypercholesterolemia, and smoking incidences were similar in both groups. There were significantly more patients reporting no discomfort in the TR band group compared to the Radistop group (77% vs. 61%; P = 0.0001). Patients in the Radistop group reported significantly more pain across all categories of severity and three patients in the Radistop group were crossed over to TR band because of severe discomfort. Oozing and ecchymosis were seen in about 16% of the patients. Local small hematoma and large hematoma were seen in 5.4% and 2.2% patients respectively, and similar in both groups. Radial artery occlusion at the time of discharge was seen in 9.2% of the patients though only 6.8% showed persistent occlusion at the time of follow‐up. The time taken to achieve hemostasis was significantly longer in the TR Band group (5.32 ± 2.29 vs. 4.83 ± 2.23 hr; P = 0.004). There was significantly higher incidence of radial artery occlusion in patients with smaller wrist circumference, the patients who experienced radial artery spasm during the procedure, and patients with no heparin administration during the procedure. Conclusions: We have shown in a randomized comparison of Radistop and TR band that both devices are safe and effective as hemostatic compression devices following transradial procedures. However, more patients felt discomfort with the Radistop device and the time taken to achieve hemostasis was longer with TR band.


Heart | 2006

Stent expansion: a combination of delivery balloon underexpansion and acute stent recoil reduces predicted stent diameter irrespective of reference vessel size

Shahid Aziz; John L. Morris; Raphael A. Perry; Rodney H. Stables

Background: There is a strong inverse relationship between final vessel diameter and subsequent risk of treatment failure after coronary stent deployment. The aim of this study was to investigate the magnitude by which stent delivery balloon underexpansion and stent elastic recoil contributed to suboptimal final vessel geometry. Methods: A prospective angiographic study recruiting 499 lesions (385 patients) undergoing coronary stent implantation was performed. Quantitative coronary angiography (QCA) was used to measure the minimal lumen diameters of the delivery balloon during stent deployment (MLD1) and of the stented segment following balloon deflation (MLD2). The expected balloon diameter for the deployment pressure was determined from the manufacturer’s reference chart. Delivery balloon deficit was measured by subtracting the MLD1 from the expected balloon size and stent recoil was calculated by subtracting MLD2 from MLD1. Delivery balloon deficit and stent recoil were examined as a function of reference vessel diameter (RVD) and balloon–vessel (BV) ratio. Results: The final stent MLD was a mean 27.2% (SD = 7.2) less than the predicted diameter. The mean delivery balloon deficit was 0.65 mm (SD = 0.27) and the mean stent recoil was 0.28 mm (SD = 0.17). Percentage delivery balloon deficit and stent recoil were independent of RVD. Delivery balloon deficit increased with higher BV ratios. Stent recoil was independent of BV ratio and the use of predilatation. Conclusion: Failure to achieve predicted final stent diameter is a real problem with contribution from delivery balloon underexpansion and stent recoil. On average the final stent MLD is only 73% of the expected diameter, irrespective of vessel size.


Clinical Science | 2010

Impact of catheter insertion using the radial approach on vasodilatation in humans

Ellen A. Dawson; Sudhir Rathore; N. Timothy Cable; D. Jay Wright; John L. Morris; Daniel J. Green

The aim of this study was to determine the impact of catheter sheath insertion, a model of endothelium disruption in humans, on the conventional FMD (flow-mediated dilatation) response in vivo. Seventeen subjects undergoing transradial catheterization were recruited and assessed prior to, the day after, and 3-4 months postcatheterization. The catheter sheaths external diameter was 2.7 mm, and the average preprocedure internal radial artery diameter was 2.8 mm, indicating a high likelihood of endothelial denudation as a consequence of sheath placement. Radial artery flow-mediated and endothelium-derived NO (nitric oxide)-dependent function (FMD) was assessed within the region of sheath placement (sheath site) and also above the sheath (catheter site). GTN (glyceryl trinitrate) endothelium-independent NO-mediated function was also assessed distally. Measurements were made in both arms at all time points; the non-catheterized arm provided an internal control. Neither sheath (4.5+/-0.9%) nor catheter (4.4+/-0.9%) insertion abolished FMD, although both significantly decreased FMD from preintervention levels (9.0+/-0.8% sheath segment; 8.4+/-0.8% catheter segment; P<0.05). The impact of sheath and catheter placement on FMD was no longer evident after approximately 3 months recovery (8.0+/-1.5 and 8.1+/-1.7%, sheath and catheter, respectively). GTN responses also decreased from 14.8+/-1.7 to 7.9+/-1.0% (P<0.05) as a result of sheath placement, but values returned to baseline at approximately 3 months (13.0+/-1.8%). These results suggest that the presence of an intact, functional endothelial layer and consequent NO release may not be obligatory for some component of the FMD response. This raises the possibility of an endothelium-independent contribution to the flow-induced vasodilatation in humans.


Circulation-cardiovascular Interventions | 2010

Impact of Introducer Sheath Coating on Endothelial Function in Humans After Transradial Coronary Procedures

Ellen A. Dawson; Sudhir Rathore; N. Timothy Cable; D. Jay Wright; John L. Morris; Daniel J. Green

Background—The aim of this study was to compare the impact of transradial catheterization with hydrophilic-coated catheter sheaths versus uncoated sheaths on NO-mediated endothelial-dependent and -independent vasodilator function. Methods and Results—Thirty-five subjects undergoing transradial catheterization were recruited and assessed before and the day after catheterization. A subgroup was also assessed 3 to 4 months after catheterization. Subjects received hydrophilic-coated sheaths (n=15) or uncoated sheaths (n=20). Radial artery flow-mediated dilatation and endothelium- and NO-dependent arterial dilatation were assessed within the region of sheath placement. Glyceryl trinitrate endothelium-independent NO-mediated function was also assessed. The noncatheterized arm provided an internal control. Flow-mediated dilatation in the catheterized arm decreased from 10.3±3.8% to 5.3±3.3% and 8.1±2.4% to 5.2±3.7% in the coated and uncoated groups, respectively (P<0.01). These values returned toward baseline levels ≈3 months later (coated, 6.4±1.4%; uncoated, 9.4±4.1%; P<0.05) versus postprocedure. Glyceryl trinitrate decreased from 14.8±7.2% to 9.5±4.1% (P<0.05) in the coated group and from 12.2±4.6% to 7.5±4.2% (P<0.01) in the uncoated group. Values returned to baseline at ≈3 months (coated, 16.6±5.6%; uncoated, 12.1±3.9%; P<0.05). There was no difference in the magnitude of decrease in flow-mediated dilatation or glyceryl trinitrate between coated and uncoated groups. No changes in function occurred in the noncatheterized arm. Conclusions—Placement of a catheter sheath inside the radial artery disrupts vasodilator function, which recovers after 3 months. No differences were evident between hydrophilic-coated and uncoated sheaths.


Journal of Interventional Cardiology | 2009

The feasibility of percutaneous transradial coronary intervention for saphenous vein graft lesions and comparison with transfemoral route.

Sudhir Rathore; Elved Roberts; Abdul Hakeem; Maheshwar Pauriah; Andrew Beaumont; John L. Morris

BACKGROUND Transradial PCI is rapidly expanding and is effective in complex lesion subset due to miniaturization of devices and accumulated clinical experience. However, the femoral route still remains the usual vascular route used for SVG PCI in most catheterization laboratories. METHODS We examined 115 consecutive patients undergoing SVG PCI between January 2003 and December 2005 and compared the radial (51 patients) and femoral (64 patients) approaches. RESULTS Baseline demographics, lesion location, and clinical indication were similar in both groups. GpIIbIIIa inhibitor usage was high in the radial group (78.4% vs. 53.1%, P < 0.01). Angiographic success was similar in both groups, 96% in the radial group vs. 96.8 in the femoral. Total fluoroscopy time (18.59 +/- 12.23 vs. 20.45 +/- 12.9), total procedure time (52.1 +/- 29.5 vs. 43.90 +/- 23.31 min), and the use of total contrast volume (357.0 +/- 174.0 vs. 346.0 +/- 157.0 ml) were similar in the radial and femoral groups, respectively. In-hospital MACE (radial: 2 MI [4.0%] vs. femoral: 1 death [1.6%] and 7 MI [11.0%], P < 0.01) were similar in both groups. Access site vascular complications (radial: 2 [4.0%] vs. femoral: 10 [11.0%], P < 0.001) were significantly less in the radial group. CONCLUSIONS The transradial approach for SVG PCI is feasible, safe, and as quick as the femoral approach. Procedural success is high with similar radiation and contrast exposure. In-hospital MI in the femoral group is high because of more-unstable patients. However, there are significantly lower vascular complications despite high use of platelet inhibitors in the radial approach.


Heart | 1997

If Rotablator is useful, why don't we use it?

David R. Ramsdale; John L. Morris

manufacturer has produced tapered, more flexible guidewires that straighten arterial contours less and push the burr into the edge of a curve less forcefully. The distal 9 cm of the drive shaft tubing was removed, also making the shaft more flexible. With evolution of the shaft-guidewire system biased cutting is reduced. However, in severely angulated segments such as the takeoff of a left circumflex from the left main coronary artery with an angle > 1200, a more substantial wire (type C or Extra Support) can be preshaped to match the anatomy. This lesion specific prebending provides more complete abrasion of the plaque with decreased deeply biased cutting.


Heart | 2010

034 A randomised comparison of TR band and Radistop haemostatic compression devices after transradial coronary intervention

Sudhir Rathore; Rod Stables; M Pauriah; M Hakeem; J D Mills; Nicholas D. Palmer; Raphael A. Perry; John L. Morris

Introduction The transradial route for coronary intervention has proven to be safe, effective, and widely applicable in different clinical situations. Several compressive haemostatic devices have been introduced which have shown to be safe and are effective in achieving haemostasis. Aims of Study Two commonly-used compressive devices to achieve haemostasis after transradial access are the Radistop (RADI, Uppsala, Sweden), and the TR Band (Terumo Inc, Japan). The objectives of our study are to compare the effects of Radistop and TR band on patients comfort, time taken to achieve haemostasis and local vascular complications. Methods Seven hundred and ninety patients were randomly assigned to receive either TR band or Radistop after transradial procedure. The outcome measures were patient tolerance of the device, local vascular complications, and the time taken to achieve haemostasis. Results The mean age was 62.88 years, and 74.2% of the patients were men. Patient age, height, weight, wrist circumference, body mass index, male sex, hypertension, diabetes, hypercholesterolaemia and smoking incidence were similar in both groups. There were significantly more patients reporting no discomfort in the TR band group compared to the Radistop group (77% vs 61%; p=0.0001). Patients in the Radistop group reported significantly more pain across all categories of severity and three patients in the Radistop group were crossed over to TR band because of severe discomfort. Oozing and ecchymosis were seen in about 16% of the patients. Local small haematoma and large haematoma were seen in 5.4%, and 2.2% patients respectively, and similar in both groups. Radial artery occlusion at the time of discharge was seen in 9.2% of the patients though only 6.8% showed persistent occlusion at the time of follow-up. The time taken to achieve haemostasis was significantly longer in the TR Band group (5.32±2.29 vs 4.83±2.23 h; p=0.004). There was significantly higher incidence of radial artery occlusion in patients with smaller wrist circumference, the patients who experienced radial artery spasm during the procedure, and patients with no heparin administration during the procedure. Conclusions We have shown in a randomised comparison of Radistop and TR band, that both devices are safe and effective as haemostatic compression devices following transradial procedures. However, more patients felt discomfort with the Radistop device and the time taken to achieve haemostasis was longer with TR band.

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Dive into the John L. Morris's collaboration.

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Sudhir Rathore

Liverpool John Moores University

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Abdul Hakeem

University of Arkansas for Medical Sciences

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Rod Stables

Imperial College London

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D. Jay Wright

Liverpool John Moores University

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Ellen A. Dawson

Liverpool John Moores University

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Ian Kemp

Liverpool Heart and Chest Hospital NHS Trust

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