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289 result(s) for "Schofield, Peter M"
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Relationship between the EQ-5D index and measures of clinical outcomes in selected studies of cardiovascular interventions
Background The EuroQoL 5D (EQ-5D) has been widely used in studies of cardiac disease, but its measurement properties in this group are not well established. The study aimed to quantify the relationship between measures commonly used in studies of cardiac disease and the EQ-5D index across different levels of disease severity. Methods Patient-level data from 7 studies of cardiac interventions were used, which included randomised trials and observational studies. Relationships between the EQ-5D index and commonly used cardiac measures, Canadian Cardiovascular Society (CCS) angina severity class, treadmill exercise time (ETT) and scales of the Seattle Angina Questionnaire (SAQ) were examined. Mixed effects linear regression was used to assess these relationships, with the EQ-5D index as the response. Results Study sample sizes ranged from 68 to 2419. Mean baseline EQ-5D index ranged from 0.77 in patients at diagnosis (95% CI 0.75, 0.78) to 0.43 in patients with advanced disease (95% CI 0.39, 0.48) and differed significantly across studies (p < 0.001). There was evidence of a ceiling effect in patients at diagnosis. The minimum clinically important difference of a one minute increase in ETT was associated with a 0.019 (95% CI 0.014, 0.025) increase in EQ-5D index. One class increase in CCS was associated with a 0.11 (95% CI 0.09, 0.13) decrease in EQ-5D index. A 10 unit increase in SAQ scales was associated with increases between 0.04 and 0.07 in EQ-5D index (95% CIs 0.03, 0.05 and 0.05, 0.08). Tests of heterogeneity indicated the EQ-5D-covariate relationships were consistent across levels of disease severity for ETT and the treatment satisfaction scale of the SAQ, but heterogeneous for age, gender, CCS angina class and other scales of the SAQ. Conclusion The EQ-5D index varies with coronary disease severity. The relationship between the EQ-5D index and an outcome measure used in cardiac intervention studies, ETT, was consistent across disease severity levels, but the relationship between demographic variables, CCS angina class and most of the SAQ scales and the EQ-5D index was heterogeneous for patients with different levels of coronary disease. Differences in the EQ-5D index associated with clinically important differences in cardiac measures can be quantified and vary between three important examples - angina class, ETT and SAQ.
Minimally Invasive Techniques for the Treatment of Patients with Structural Heart Disease
Historically, patients with advanced structural heart disease have required major surgery to correct the defect. This includes for example, patients with atrial septal defect, aortic valve disease and mitral valve disease. In recent years there have been major advances in the treatment of patients with structural heart disease using minimally invasive, percutaneous treatments. This field continues to evolve quite quickly.This e-book outlines the current situation with respect to minimally invasive treatment of a wide range of structural cardiac defects. Each chapter covers details of a structural defect and outlines various technologies available for treating the condition. Indications for procedures as well as details of the procedures are also provided wherever possible. This e-book should be a useful reference for readers interested in minimally invasive cardiovascular surgery.
Proton NMR analysis of plasma is a weak predictor of coronary artery disease
Multivariate analysis of 1 H-NMR spectra of blood sera was reported previously to predict angiographically defined advanced coronary artery disease (CAD) with >90% accuracy and specificity. The analysis depended mainly on the major lipid regions of the spectra, but many variables, including gender and drug treatment, affect lipid composition and are potential confounders. We have determined the predictive power of the same methodology for angiographically defined CAD using plasma samples from groups of male patients, classified by statin treatment, who had normal coronary arteries (NCAs) or CAD. Predictions for NCA and CAD groups were only 80.3% correct for patients not treated with statins and 61.3% for treated patients, compared with random correct predictions of 50%. A confidence limit of >99% was achieved for 36.2% of predictions for untreated groups and 6.2% for treated groups. Detection of CAD by 1 H-NMR with >99% confidence was therefore very weak compared with angiography.
Left bundle branch block with acute thrombotic occlusion is associated with increased myocardial jeopardy score and poor clinical outcomes in primary percutaneous coronary intervention activations
Objective To assess the utility of left bundle branch block (LBBB) as an activation criterion for primary percutaneous coronary intervention (PPCI). Design Retrospective observational cohort study. Setting Single UK heart attack centre. Patients Consecutive patients referred for PPCI September 2008–December 2011 (n=2192). Interventions Demographic and outcome data were obtained by review of case notes, angiograms and interrogation of local/national databases. Main outcome measures Angiographic culprit lesion assessment defined appropriate and inappropriate activations. Patients outcomes were assessed by Major adverse cardiac events (MACE), defined as a composite of mortality and unplanned revascularisation at 1-year. Results LBBB-activation occurred in 120 patients (5.5%), of whom 21 (17.5%) had acute coronary occlusion angiographically, and were adjudicated appropriately. Compared with appropriate activations for ST segment elevation, appropriate LBBB-activations were older (71.0±9.6 vs 64.2±12.4 years, p=0.01) and more likely to be in cardiogenic shock (19.0% vs 4.3%, p<0.01). Extent of disease quantified by the SYNTAX score did not differ (median 21.5, IQR 11.0–27.0 vs 19, 11.0–25.5, p=0.66), but amount of myocardium at-risk was higher in appropriate LBBB-activations (culprit jeopardy score median 4, IQR 2–6 vs 2, 2–4, p=0.02). Final diagnoses for LBBB-activations were acute coronary syndrome (39.2%), non-acute coronary syndrome cardiac chest pain (33.3%) and non-cardiac chest pain (27.5%). In appropriate LBBB-activations 1-year mortality and MACE were higher (23.8% vs 6.6%, p=0.002 and 28.6% vs 10.5%, p=0.007, respectively). Conclusions Our data suggests that despite its poor specificity for identifying acute coronary occlusion, LBBB should at the present time remain an activation criterion for PPCI and such patients should continue to be transferred to heart attack centres for assessment and treatment.
A study to assess changes in myocardial perfusion after treatment with spinal cord stimulation and percutaneous myocardial laser revascularisation; data from a randomised trial
Background Spinal cord stimulation (SCS) and percutaneous myocardial laser revascularisation (PMR) are treatment modalities used to treat refractory angina pectoris, with the major aim of such treatment being the relief of disabling symptoms. This study compared the change in myocardial perfusion following SCS and PMR treatment. Methods Subjects with Canadian Cardiovascular Society class 3/4 angina and reversible perfusion defects as assessed by single-photon emission computed tomographic myocardial perfusion scintigraphy were randomised to SCS (34) or PMR (34). 28 subjects in each group underwent repeat myocardial perfusion imaging 12 months post intervention. Visual scoring of perfusion images was performed using a 20-segment model and a scale of 0 to 4. Results The mean (standard deviation) baseline summed rest score (SRS) and stress scores (SSS) were 4.6 (5.7) and 13.6 (9.0) in the PMR group and 6.1 (7.4) and 16.8 (11.6) in the SCS group. At 12 months, SRS was 5.5 (6.0) and SSS 15.3 (11.3) in the PMR group and 6.9 (8.2) and 15.1 (10.9) in the SCS group. There was no significant difference between the two treatment groups adjusted for baseline (p = 1.0 for SRS, p = 0.29 for SSS). Conclusion There was no significant difference in myocardial perfusion one year post treatment with SCS or PMR.
Rapid and noninvasive diagnosis of the presence and severity of coronary heart disease using 1H-NMR-based metabonomics
Although a wide range of risk factors for coronary heart disease have been identified from population studies, these measures, singly or in combination, are insufficiently powerful to provide a reliable, noninvasive diagnosis of the presence of coronary heart disease. Here we show that pattern-recognition techniques applied to proton nuclear magnetic resonance ( 1 H-NMR) spectra of human serum can correctly diagnose not only the presence, but also the severity, of coronary heart disease. Application of supervised partial least squares-discriminant analysis to orthogonal signal-corrected data sets allows >90% of subjects with stenosis of all three major coronary vessels to be distinguished from subjects with angiographically normal coronary arteries, with a specificity of >90%. Our studies show for the first time a technique capable of providing an accurate, noninvasive and rapid diagnosis of coronary heart disease that can be used clinically, either in population screening or to allow effective targeting of treatments such as statins.
Randomised controlled trial of vitamin E in patients with coronary disease: Cambridge Heart Antioxidant Study (CHAOS)
Summary Background Vitamin E (α-tocopherol) is thought to have a role in prevention of atherosclerosis, through inhibition of oxidation of low-density lipoprotein. Some epidemiological studies have shown an association between high dietary intake or high serum concentrations of α-tocopherol and lower rates of ischaemic heart disease. We tested the hypothesis that treatment with a high dose of α-tocopherol would reduce subsequent risk of myocardial infarction (MI) and cardiovascular death in patients with established ischaemic heart disease. Methods In this double-blind, placebo-controlled study with stratified randomisation, 2002 patients with angiographically proven coronary atherosclerosis were enrolled and followed up for a median of 510 days (range 3-981). 1035 patients were assigned α-tocopherol (capsules containing 800 IU daily for first 546 patients; 400 IU daily for remainder); 967 received identical placebo capsules. The primary endpoints were a combination of cardiovascular death and non-fatal MI as well as non-fatal Ml alone. Findings Plasma α-tocopherol concentrations (measured in subsets of patients) rose in the actively treated group (from baseline mean 34·2 μmol/L to 51·1 μmol/L with 400 IU daily and 64·5 μmol/L with 800 IU daily) but did not change in the placebo group. α-tocopherol treatment significantly reduced the risk of the primary trial endpoint of cardiovascular death and non-fatal Ml (41 vs 64 events; relative risk 0·53 [95% Cl 0·34-0·83; p=0·005). The beneficial effects on this composite endpoint were due to a significant reduction in the risk of non-fatal Ml (14 vs 41; 0·23 [0·11-0·47]; p=0·005); however, there was a non-significant excess of cardiovascular deaths in the α-tocopherol group (27 vs 23; 1·18 [0·62-2·27]; p=0·61). All-cause mortality was 36 of 1035 α-tocopherol-treated patients and 27 of 967 placebo recipients. Interpretation We conclude that in patients with angiographically proven symptomatic coronary atherosclerosis, α-tocopherol treatment substantially reduces the rate of non-fatal MI, with beneficial effects apparent after 1 year of treatment. The effect of α-tocopherol treatment on cardiovascular deaths requires further study.
Mortality in the CHAOS trial
Results of the CHAOS trial of alpha-tocopherol showed a 75% decrease in non-fatal myocardial infarction in the alpha-tocopherol group, but apparently no effect on mortality. Mitchinson et al discuss more accurate study of deaths and of compliance.