Jonathan Blaxill
Leeds General Infirmary
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Featured researches published by Jonathan Blaxill.
American Heart Journal | 2008
Michael F. Dorsch; John P. Greenwood; Claire Priestley; Kathryn Somers; Carole Hague; Jonathan Blaxill; Stephen B. Wheatcroft; Alan F. Mackintosh; James McLenachan; Daniel J. Blackman
BACKGROUND Primary percutaneous coronary intervention (PCI) is the preferred treatment for ST-segment elevation myocardial infarction (STEMI) provided it can be delivered within 90 minutes of hospital admission. In clinical practice this target is difficult to achieve. We aimed to determine the effect of direct ambulance admission to the cardiac catheterization laboratory on door-to-balloon and call-to-balloon times in primary PCI. METHODS We performed a prospective evaluation of a new system of paramedic electrocardiogram diagnosis of STEMI and subsequent direct ambulance admission to the cardiac catheterization laboratory for primary PCI. Door-to-balloon and call-to-balloon times were recorded for all patients. Direct admissions were compared with admissions via the emergency room of the interventional center and of 2 referring hospitals. All times are quoted as medians. RESULTS Five hundred and seventy-seven patients (70% male, age 63 +/- 13 years) underwent primary PCI between April 2005 and May 2007. After February 2006, 172 (44%) of 387 patients were admitted directly from the ambulance to the catheterization laboratory. Directly admitted patients had significantly reduced door-to-balloon (58 vs 105 minutes, P < .001) and call-to-balloon times (105 vs 143 minutes, P < .001). The 90-minute target for door-to-balloon time was achieved in 94% of direct admissions compared to 29% of patients referred from the emergency room. CONCLUSIONS Direct admission of patients with suspected STEMI from the ambulance service to the catheterization laboratory significantly reduces time to treatment in primary PCI and allows the 90-minute door-to-balloon time target to be reliably achieved.
Diabetes and Vascular Disease Research | 2012
Matthew Kahn; Richard M. Cubbon; Ben Mercer; Alison Wheatcroft; Guy Gherardi; Amir Aziz; Jonathan Blaxill; Jim McLenachan; Daniel J. Blackman; John P. Greenwood; Stephen B. Wheatcroft
Background: We investigated the association between diabetes mellitus (DM) and all-cause mortality in a large cohort of consecutive patients treated with primary percutaneous coronary intervention (PPCI) in the contemporary era. Methods: We conducted a retrospective analysis of a single-centre registry of patients undergoing PPCI for ST-segment elevation myocardial infarction (STEMI) at a large regional PCI centre between 2005 and 2009. All-cause mortality in relation to patient and procedural characteristics was compared between patients with and without DM. Results: Of 2586 patients undergoing PPCI, 310 (12%) had DM. Patients with DM had a higher prevalence of multi-vessel coronary disease (p<0.001) and prior myocardial infarction (p<0.001). Patients with DM were less commonly admitted directly to the interventional centre (p=0.002). Symptom-to-balloon (p<0.001) and door-to-balloon time (p=0.002) were longer in patients with DM. Final infarct-related-artery TIMI-flow grade was lower in patients with DM (p=0.031). All-cause mortality at 30 days (p=0.0025) and 1 year (p<0.0001) was higher in patients with DM. DM was independently associated with increased mortality after multivariate adjustment for potential confounders. Conclusions: Mortality remains substantially higher in patients with DM following reperfusion for STEMI in comparison with those without diabetes, despite contemporary management with PPCI. Greater co-morbidity, delayed presentation, longer times-to-reperfusion, and less optimal reperfusion may contribute to adverse outcomes.
American Heart Journal | 2010
Rhidian J. Shelton; Andrew M. Crean; Kathryn Somers; Claire Priestley; Carol Hague; Jonathan Blaxill; Stephen B. Wheatcroft; James McLenachan; John P. Greenwood; Daniel J. Blackman
BACKGROUND It remains unclear whether the superiority of primary percutaneous coronary intervention (PPCI) over thrombolysis for the treatment of ST elevation myocardial infarction (STEMI) extends to the very elderly. Furthermore, the deliverability and efficacy of PPCI in over the 80s has not been investigated in a real-world setting. The aim of this study was to compare outcome from STEMI in patients aged > or =80 before and after the introduction of routine 24/7 PPCI. METHODS Retrospective observational analysis of all patients aged > or =80 presenting with STEMI to 2 neighboring hospitals in the 3-year period after the introduction of a 24/7 PPCI service and in the preceding 2 years when reperfusion therapy was by thrombolysis. RESULTS Two hundred fifty-six STEMI patients aged > or =80 were included. After the introduction of PPCI, 84% (136/161) received reperfusion therapy, 73% PPCI, and 12% thrombolysis, compared to 77% ([73/95] 1% PPCI, 76% thrombolysis) previously. Mortality after inception of PPCI was reduced at 12 months (29% vs 41%, P = .04) and 3 years (43% vs 58%, P = .02). Improved outcome was attributable to treatment by PPCI, which was associated with numerically lower 12-month (26% vs 37%, P = .07) and significantly reduced 3-year (42% vs 55%, P = .05) mortality compared to thrombolysis. CONCLUSIONS Primary PCI can be effectively delivered to very elderly patients presenting with ST elevation MI in a real-world setting and leads to a substantial reduction in mortality compared to patients treated by thrombolysis.
Catheterization and Cardiovascular Interventions | 2016
Christos Eftychiou; David Barmby; Simon Wilson; Salahaddin Ubaid; Andrew J. Markwick; Loukia Makri; Jonathan Blaxill; James C. Spratt; Mark Gunning; John P. Greenwood
To identify factors associated with outcomes following rotational atherectomy (RA).
Catheterization and Cardiovascular Interventions | 2016
Christos Eftychiou; David Barmby; Simon Wilson; Salahaddin Ubaid; Andrew J. Markwick; Loukia Makri; Jonathan Blaxill; James C. Spratt; Mark Gunning; John P. Greenwood
To identify factors associated with outcomes following rotational atherectomy (RA).
American Journal of Cardiology | 2013
Sreekanth Vemulapalli; Yi Zhou; Matthias Gutberlet; Arramraj Sreenivas Kumar; James S. Mills; Jonathan Blaxill; Richard W. Smalling; Erik Magnus Ohman; Manesh R. Patel
The goal of this study was to characterize determinants of infarct size in the multicenter randomized Counterpulsation to Reduce Infarct Size Pre-PCI Acute Myocardial Infarction (CRISP-AMI) trial. Contemporary determinants of infarct size in patients presenting with acute anterior myocardial infarction without shock and undergoing percutaneous revascularization have been incompletely characterized. In CRISP-AMI, 337 patients with acute anterior ST segment elevation myocardial infarction but without cardiogenic shock at 30 sites in 9 countries were randomized to initiation of intra-aortic balloon counterpulsation before primary percutaneous coronary intervention versus standard of care. The primary outcome was infarct size as measured by cardiac magnetic resonance imaging 3 to 5 days after percutaneous coronary intervention. Of 337 randomized patients, complete periprocedural and infarct size data were available in 250 patients (74%). After a comparison of baseline characteristics to ensure no significant differences, patients with missing data were excluded. Using multiple linear regression of 23 variables, time from symptom onset to first device (β = 0.022, p = 0.047) and preprocedural Thrombolysis In Myocardial Infarction flow 0/1 (β = 15.28, p <0.001) were independent predictors of infarct size. Infarct size increased by 0.43% per 30 minutes in early reperfusion and by 0.63% every 30 minutes in late reperfusion. In conclusion, in patients with acute anterior ST elevation myocardial infraction without cardiogenic shock, total ischemic time and preprocedural Thrombolysis In Myocardial Infarction flow 0/1 were associated with increased infarct size as determined by cardiac magnetic resonance imaging. These findings underscore the importance of systems of care aimed at reducing total ischemic time to open infarct arteries.
Journal of Interventional Cardiology | 2011
Rhidian J. Shelton; Kamal Chitkara; Ravi Singh; Micha F. Dorsch; Kathryn Somers; James McLenachan; Jonathan Blaxill; Stephen B. Wheatcroft; Daniel J. Blackman; John P. Greenwood
Primary percutaneous coronary intervention (PPCI) is superior to thrombolysis in STEMI (ST segment elevation myocardial infarction) patients. Data on late stent thrombosis (ST) have raised concerns regarding the use of drug-eluting stents during PPCI. We report the first 3-year clinical evaluation of the zotarolimus-eluting stent (ZES) in patients undergoing PPCI for STEMI, a single-center, prospective cohort study of consecutive patients admitted with STEMI. All underwent PPCI within 12 hours of symptoms; each received one or more ZES in one or more target lesions. All patients received aspirin 300 mg, clopidogrel 600 mg, abciximab, and unfractionated heparin. A total of 102 STEMI patients (76 male, mean 62 years) received 162 ZES (mean 1.6 stents/patient). Median call-to-balloon time was 123 (102-152) minutes. Thirty-day combined major adverse cardiovascular event (MACE) rate was 3.9% (n = 4). Subacute ST occurred in 2 patients (1.96%). Combined MACE rates at 12 months and 3 years were 7.8% (n = 8) and 13.7% (n = 14). Late ST occurred in 1 patient (1%) with no occurrence of very late ST. This is the first 3-year report of the use of the ZES in an unselected, consecutive PPCI population. Overall 3-year incidence of MACE and target lesion revascularization (5.9%) was low, and was comparable to that seen with sirolimus- and paclitaxel-eluting stents in randomized controlled trials. At 3 years there was no occurrence of very late ST.
Clinical Cardiology | 2015
W. Schuyler Jones; Robert Clare; Karen Chiswell; Divaka Perera; John K. French; A. Sreenivas Kumar; Jonathan Blaxill; Nico H.J. Pijls; James S. Mills; E. Magnus Ohman; Manesh R. Patel
Primary percutaneous coronary intervention (PCI) is the most common method of reperfusion in patients with ST‐segment elevation myocardial infarction (STEMI) in the United States. The intersection between processes of care and performance measures such as door‐to‐balloon (D2B) times and clinical trials evaluating novel therapies for STEMI has not been fully investigated.
European heart journal. Acute cardiovascular care | 2017
Arvindra Krishnamurthy; Claire Keeble; Natalie Burton-Wood; Kathryn Somers; Michelle Anderson; Charlotte Harland; Paul D. Baxter; James McLenachan; Jonathan Blaxill; Daniel J. Blackman; Christopher J Malkin; Stephen B. Wheatcroft; John P. Greenwood
Background: Female sex and South Asian race have been associated with poor clinical outcomes following primary percutaneous coronary intervention (PPCI) for ST-segment elevation myocardial infarction (STEMI) but remain understudied in large real-world series. We therefore investigated the association of sex and race with clinical outcomes following PPCI. Methods: We conducted a prospective study of all patients undergoing PPCI for STEMI between January 2009 and December 2011 at a large UK cardiac centre. Clinical characteristics and outcomes were compared according to sex and race using Chi-square test, independent samples Student’s t-test and Mann–Whitney U-test. Primary and secondary outcomes were 12-month major adverse cardiovascular events (MACEs) – defined as all-cause mortality, myocardial infarction and unplanned revascularization, analysed using Cox proportional hazard models adjusting for cardiovascular risk factors. Results: Three thousand and forty-nine patients were included. Women (n=826) were older than men (n=2223) (median age 69 vs. 60 years, p <0.01). Mortality (hazard ratio 1.48 (1.15–1.90)) and MACE (hazard ratio 1.40 (1.14–1.72)) were higher in women in univariable analysis. However, there were no significant sex-differences in mortality or MACE after age-stratification alone. Multivariable analysis also showed no significant differences in outcomes between sexes. South Asians (n=297) were younger but had a higher prevalence of most risk factors than White patients (n=2570). Mortality and MACE did not differ significantly between South Asian and White patients in univariable or multivariable analysis. Conclusion: MACE and mortality was not greater in women, or in South Asian patients following PPCI after adjustment for cardiovascular risk factors including age, which was most strongly associated with both outcomes.
Heart | 2016
Arvindra Krishnamurthy; Kathryn Somers; Natalie Burton-Wood; Michelle Anderson; Charlotte Harland; Claire Keeble; James McLenachan; Jonathan Blaxill; Christopher Malkin; Daniel J. Blackman; Stephen B. Wheatcroft; John P. Greenwood
Introduction Clinical outcomes following Primary PCI (PPCI) for ST Elevation Myocardial Infarction (STEMI) continue to improve with the evolution of techniques and pharmacotherapy. The West Yorkshire PPCI study was set up to allow identification of clinical and procedural variables that could impact on outcomes following PPCI. We analysed the influence of ethnicity on major adverse cardiovascular events (MACE) and mortality following PPCI. Methods Retrospective analysis of 3049 consecutive patients undergoing PPCI for STEMI between 01–01–2009 and 31–12–2011 at Leeds General Infirmary. Clinical data up to a minimum of 12m following PPCI were collected. Analyses of total mortality and MACE of white patients (n = 2570, mean 64 ± 13yrs) and Asian patients (n = 297, mean 58 ± 14yrs) were performed with Cox proportional hazards models. MACE was defined as death, MI and unplanned revascularisation. Results There was no statistically significant difference in outcomes between the ethnic groups (Figure 1). Abstract 33 Figure 1 Kaplan-Meier survival curves for total mortality and MACE Discussion and conclusion This large retrospective study has revealed no statistically significant difference in mortality or MACE between Asian and white patients following PPCI.