Search PubMed⌕ Search

Biomedical subjects

T J Bowker

Publications and source records attributed to T J Bowker.

At least 19 recordsLinked to original sources
PubMed2003

Sudden, unexpected cardiac or unexplained death in England: a national survey.

BACKGROUND: Post-mortem examinations of adults who were apparently healthy but died suddenly and unexpectedly sometimes reveal no morphological abnormalities to explain their deaths. The frequency of such unexplained deaths in relation to other causes of sudden cardiac death is not known. AIM: To estimate the frequency of sudden unexpected cardiac or unexplained death in England. DESIGN: Prospective survey using a stratified random sample of 83 of the 132 H.M. Coroner's jurisdictions in England. METHODS: Consecutive White Caucasians, aged 16-64 years, with no medical history of cardiac disease, seen alive within 12 h of death, on whom autopsy found either a cardiac or no identifiable cause of death, were included. The coroner's officer sent a copy of the post-mortem report and a completed case registration form to the investigators, with tissue samples. RESULTS: Sixty-seven (81%) coroners participated, each maintaining prospective surveillance for 4 months. Of 692 ascertained cases, case registration forms were received for 650 (94%), post-mortem reports for 682 (99%), blood samples for 569 (82%), myocardial slices for 517 (75%) and whole hearts for 47 (7%). In cases with myocardial tissue, death was ascribed to ischaemic heart disease in 465 (82.4%). In 43.1% the ischaemia was acute, in 19.1% there was myocardial scarring but no acute ischaemia, and 20.2% had coronary atheroma only. Death was due to left ventricular hypertrophy in 32 (5.7%), to other cardiac causes in 30 (5.3%) and in 23 (4.1%) there was no clear cause. Those with cardiac causes were 81% male, median ages 55.9 (male) and 56.6 (female) years. The 23 unexplained deaths were 57% female, median ages 40.5 (male) and 54.9 (female) years. The estimated annual frequency of sudden unexpected death due to cardiac or unidentified causes, in English adults of employment age, was 11/100,000 (3481 annual deaths). DISCUSSION: In 4.1% of sudden unexpected deaths under 65 years, no cause was found. Until it becomes accepted practice to identify these cases by a name, such as Sudden Adult Death Syndrome (SADS), it will not be possible to study their aetiology systematically.

Adolescent↗
PubMed2002

Gender differences in the management and outcome of patients with acute coronary artery disease.

STUDY OBJECTIVE: s: To compare the clinical management and health outcomes of men and women after admission with acute coronary syndromes, after adjusting for disease severity, sociodemographic, and cardiac risk factors. DESIGN: Prospective national survey of acute cardiac admissions followed up by mailed patient questionnaire two to three years after initial admission. SETTING: Random sample of 94 district general hospitals in the UK. PATIENTS: 1064 patients under 70 years old recruited between April 1995 and November 1996. MAIN RESULTS: Of the 1064 patients recruited, 126 (11.8%) died before follow up. Of the 938 survivors, 719 (76.7%) completed a follow up questionnaire. There were no gender differences in the use of cardiac investigations during the index admission or follow up period. However, male patients with hypertension were more likely to undergo rehabilitation compared with female hypertensive patients (OR 2.01, 95% CI 0.85 to 4.72). Men were also more likely to undergo coronary artery bypass grafting (CABG) than women (OR 1.90, 95%CI 1.21 to 3.00), but there was no gender difference in the use of revascularisation overall (p=0.14). An indirect indication that the gender differences in CABG were not attributable to bias was provided by the lack of gender differences in health outcomes, which implies that patients received the care they needed. CONCLUSIONS: Despite the extensive international literature referring to a gender bias in favour of men with coronary heart disease, this national survey found no gender differences in the use of investigations or in revascularisation overall. However, the criteria used for selecting percutaneous transluminal coronary angioplasty compared with CABG requires further investigation as does the use of rehabilitation. It is unclear whether the clinical decisions to provide these procedures are made solely on the basis of clinical need.

Acute Disease↗
PubMed2001

Difference in the mortality of the CABRI diabetic and nondiabetic populations and its relation to coronary artery disease and the revascularization mode.

In diabetics with coronary artery disease (CAD), there remains uncertainty as to whether revascularization by percutaneous transluminal coronary angioplasty (PTCA) or coronary artery bypass surgery (CABG) is preferable. To address this, 4-year mortality and level of pre- and postrevascularization angiographic CAD (measured by a series of coronary scores) were compared between both diabetics and nondiabetics and between revascularization modes in the Coronary Angioplasty versus Bypass Revascularization Investigation population as a whole, and then substratified by diabetic status and then by procedure to which they were randomized. The 1,054 randomized subjects contained 125 diabetics (11.9%) who had significantly greater mortality than nondiabetics (RR 2.19, p = 0.001). Among diabetics or nondiabetics, there was no significant mortality difference between those randomized to PTCA versus those to CABG. Diabetics randomized to PTCA and those to CABG had higher mortalities than respective nondiabetics; the association reached significance only in the former (RR 2.41, p = 0.002). All subgroups had similar prerevascularization CAD. Postrevascularization residual CAD was consistently significantly greater in PTCA than in respective CABG subgroups. Most measurements of CAD were greater in diabetic than in nondiabetic subgroups, but none was significant. In the Coronary Angioplasty versus Bypass Revascularization Investigation, diabetics had double the mortality of nondiabetics; this difference was statistically significant both for the entire population and for those randomized to PTCA, but not for those randomized to CABG. Among diabetics or nondiabetics, there was no significant mortality difference between PTCA and CABG. The higher diabetic mortality was more likely related to more rapid disease progression than to greater postrevascularization disease.

Angioplasty, Balloon, Coronary↗
PubMed2001

The effect of adjusting for baseline risk factors and post revascularisation coronary disease on comparisons between coronary angioplasty and bypass surgery.

BACKGROUND: In CABRI at 1 year PTCA was associated with greater repeat revascularisation and angina (but not myocardial infarction or death). We determined whether adjusting for baseline risk factors and post revascularisation coronary disease offsets this disadvantage of PTCA. METHODS: In the CABRI population the crude association of revascularisation mode (i.e. PTCA or CABG) with four clinical outcome (i.e. mortality, myocardial infarction, repeat revascularisation and angina) was adjusted for the baseline risk factors using a logistic regression model for each clinical outcome. A number of measures of angiographic coronary disease were used to assess post revascularisation coronary disease. One at a time, each of these measures was added to each of the four outcome models, to adjust for post revascularisation coronary disease. RESULTS: Comparing adjusted and crude unadjusted association of PTCA with repeat revascularisation there was an increase from 12.8 (P<0.0005) (crude relative risk) to 16.7 (P<0.0005) (adjusted odds ratio), with angina, from 1.89 (P=0.001) to 1.98 (P<0.0019), and with mortality from 1.84 (P=0.092) to 2.15 (P=0.060). PTCA was not significantly associated with myocardial infarction, either crudely or after adjustment. CONCLUSION: Adjusting for baseline risk factors and post revascularisation coronary disease tended to strengthen rather than weaken associations between PTCA and 1 year mortality, repeat revascularisation and angina at 1 year.

Aged↗
PubMed2000

Relation between coronary artery disease, baseline clinical variables, revascularization mode, and mortality. CABRI Participants. Coronary Angioplasty vs. Bypass Revascularisation Investigation.

The Coronary Angioplasty vs. Bypass Revascularisation Investigation (CABRI) trial comparing percutaneous transluminal coronary angioplasty (PTCA) with coronary artery bypass grafting did not show a difference in mortality with either procedure. Nonrandomized studies suggest that coronary artery disease (CAD) severity and distribution influences outcome. In the present study we explored the effect of prerevascularization CAD on 1-year mortality in the CABRI population, while adjusting for other baseline variables. Of the 1,054 patients recruited, there were sufficient angiographic results to derive the CAD scores in 974 (92.4%). Of these 974, there were 32 deaths. A number of CAD scores, both weighted for proximal disease (Duke and Leaman) and nonweighted, were used. These scores were then cross-tabulated against mortality. Demographic and clinical variables were also cross-tabulated against mortality and used to derive an initial logistic regression model to predict mortality. The effect of adding each of the CAD scores to this initial model was then assessed. After inclusion of the CAD scores, the best model was: (1) presence of peripheral vascular disease (odds ratio [OR] 3.89, p = 0.0025), (2) previous cerebrovascular accident (OR 2.86, p = 0.043), (3) older age (OR 1.05, p = 0.039), (4) a higher Duke score (OR 2.84, p = 0.0061), and (5) having undergone PTCA (OR 2.12, p = 0.047). In the CABRI population, adjustment for baseline variables, including prerevascularization CAD, revealed significantly higher mortality in those who underwent PTCA than in those who underwent coronary artery bypass grafting.

Adult↗
PubMed2000

Clinical outcomes, risk stratification and practice patterns of unstable angina and myocardial infarction without ST elevation: Prospective Registry of Acute Ischaemic Syndromes in the UK (PRAIS-UK)

AIMS: To determine characteristics, outcomes, prognostic indicators and management of patients with acute coronary syndromes without ST elevation. METHODS AND RESULTS: A prospective registry was carried out with follow-up for 6 months after index hospital admission. A history of acute cardiac chest pain was required plus ECG changes consistent with myocardial ischaemia and/or prior evidence of coronary heart disease. Patients with ST elevation or those receiving thrombolytic therapy were excluded. A total of 1046 patients were enrolled from 56 U.K. hospitals. The mean age was 66+/-12 years and 39% were female. The rate of death or non-fatal myocardial infarction at 6 months was 12.2% and of death, new myocardial infarction, refractory angina or re-admission for unstable angina at 6 months was 30%. In a multivariate analysis, patients >70 years had a threefold risk of death or new myocardial infarction compared with those <60 years (P<0.01) and those with ST depression or bundle branch block on the ECG had a five-fold greater risk than those with normal ECG (P<0.001). Aspirin was given to 87% and heparin to 72% of patients in hospital. At 6 months 56% received no lipid-lowering therapy at all. The 6-month rate of coronary angiography was 27% and any revascularization 15%. CONCLUSIONS: In this cohort there was a one in eight chance of death or myocardial infarction, and a one in three chance of death, new myocardial infarction, refractory angina or re-admission for unstable angina, over 6 months. Age and baseline ECG were useful markers of risk. Aspirin, heparin and statins were not given to about one-sixth, one-third and one-half respectively. Rates of angiography and revascularization appear low. A review of treatment strategies of unstable angina and myocardial infarction without ST elevation is warranted in the U.K. to ensure that patients are receiving optimum treatments to reduce mortality and morbidity.

Acute Disease↗
PubMed2000

A national Survey of Acute Myocardial Infarction and Ischaemia (SAMII) in the U.K.: characteristics, management and in-hospital outcome in women compared to men in patients under 70 years.

AIMS: To assess the clinical characteristics, management and outcome of women compared to men with acute myocardial infarction or ischaemia. DESIGN: A prospective clinical survey was made in a random sample of 94 District General Hospitals in the U.K. 1064 patients, <70 years of age, comprising six consecutive females and six consecutive males from each hospital, diagnosed on admission as acute coronary syndromes (myocardial infarction or myocardial ischaemia) were studied. Outcome measures included: admission and final diagnosis, time to delivery of care, inpatient management, complications and clinical outcome. RESULTS: Five hundred and three women and 561 men were admitted with a diagnosis of acute myocardial infarction or myocardial ischaemia. Women were older, waited longer between seeking and receiving advice, and much less likely to have infarction than men. After adjustment for age, diagnosis and past medical history there were no gender differences in initial and subsequent hospital management, in complications (recurrent ischaemia, arrhythmias, temporary pacing, heart failure), any routine procedure or outcome. Of all patients, 3.4% died in a District General Hospital, 12.2% were transferred to Specialist Cardiac Centres and 84.4% discharged home. Prophylactic medication on discharge was similar for men and women. CONCLUSION: After adjustment for age, diagnosis and past medical history, although women waited longer between seeking and receiving medical advice, in hospital their assessment, management, complications, outcome and follow-up arrangements were the same as for men. In hospital, management and outcomes were mainly influenced by age, diagnosis (infarction or ischaemia), a past history of coronary disease, but not by gender. This large, nationally representative, survey has found no evidence of important gender difference in the hospital management of acute ischaemic syndromes.

Adult↗
PubMed2000

Cardioinhibition during tilt testing identifies patients who may benefit from pacing.

UNLABELLED: This study examined whether the various hemodynamic collapse patterns observed during tilt testing in patients with suspected neurocardiogenic syncope are relevant when planning therapy, particularly whether a predominantly cardioinhibitory response predicts a beneficial response from pacing. METHODS: The effects of temporary atrioventricular (A-V) sequential pacing were studied during tilt testing in 34 patients 48.2 +/- 18.5 years of age. The patient population was divided into a cardioinhibitory group (VASIS classes 2A and 2B) or mixed group (VASIS classes 1 and 3) according to their response to baseline tilt testing. The test was then repeated during A-V pacing with rate hysteresis. A positive response to A-V pacing was defined as a > or = 30-second increase between onset of symptoms and syncope, or mitigation of symptoms compared with the baseline tilt test. RESULTS: The study protocol was not successfully completed in three patients. Among the remaining 31 patients, a baseline cardioinhibitory response was observed in 17, and a mixed response in 14 patients. A-V sequential pacing was successful in 13 of 17 patients with a cardioinhibitory response versus 5 of 14 patients with a mixed response (P = 0.024). CONCLUSION: The presence of a predominantly cardioinhibitory collapse pattern (VASIS 2A and 2B) during baseline tilt testing doubled the likelihood of successful temporary A-V sequential pacing, and may identify patients with neurocardiogenic syncope most likely to benefit from permanent dual chamber pacing.

Blood Pressure↗
PubMed1999

Usefulness of tilt test-induced patterns of heart rate and blood pressure using a two-stage protocol with glyceryl trinitrate provocation in patients with syncope of unknown origin.

This study assesses the vasovagal collapse pattern changes, i.e, heart rate (HR) and arterial blood pressure (BP) with a 2-stage tilt-test protocol using glyceryl trinitrate (GTN) provocation. With use of the 45-minute 60 degrees head-up Westminster protocol, 102 consecutive patients were studied. Sublingual GTN 300 microg was given to those with a negative passive tilt. Heart rate and BP patterns were classified according to the Vasovagal International Study classification (VASIS) and then compared between those with a positive passive tilt and those with a positive tilt after having been given GTN. Twelve patients did not tolerate tilt testing, and 16 had a negative response despite taking GTN. Thirty-five patients (20 women and 15 men, mean age 45 +/- 21 years [mean +/- SD]) did not take GTN and 38 (26 women and 12 men, mean age 53 +/- 22 years) had positive passive test results. When comparing the VASIS classification between the 2 groups, results showed: type 1, mixed BP and HR decreased without severe bradycardia (31% [passive] vs 54% [with GTN], p = NS); type 2A, BP decreased before HR decreased (20% vs 22%, p = NS); type 2B, HR decreased before or coincident with BP (34% vs 8%, p = 0.003); type 3, BP decreased without HR decrease (9% vs 0%, p = NS); exception 1, chronotropic incompetence (0% vs 13%, p = 0.026); and exception 2, excessive HR increase (6% vs 3%, p = NS). Thus, GTN use increases frequency of positive results from 34% to 73%. Older people with chronotropic incompetence, who may benefit from pacing, were identified. In younger people there was an increase in those with cardioinhibition.

Administration, Sublingual↗
PubMed1999

Trials of angioplasty and surgery: CABRI.

The medium term (4-year post randomization) results from CABRI indicate that the principal difference between those randomized to coronary angioplasty and those to coronary surgery has been the much greater need for repeat revascularization in the former. A number of factors may play a role in the greater repeat revascularization rate post coronary angioplasty, these include coronary restenosis, residual coronary artery disease, coronary artery disease progression. In the longer term, graft failure in those who have undergone coronary surgery will be important, and it remains to be seen what the effect of this will be.

Angioplasty, Balloon, Coronary↗
PubMed1998

Impact of postangioplasty restenosis on comparisons of outcome between angioplasty and bypass grafting. Coronary Angioplasty versus Bypass Revascularisation Investigation (CABRI) Investigators.

Restenosis is a major limitation of percutaneous transluminal coronary angioplasty (PTCA). In this study, we assessed the impact of restenosis on PTCA with reference to coronary angioplasty bypass grafting (CABG). In the Coronary Angioplasty versus Bypass Revascularisation Investigation (CABRI) PTCA population, those who had restenosis were defined as those needing a second revascularization at a site revascularized at the initial procedure. The 1-year clinical outcome of the nonrestenotic group (n=437) was compared with those who underwent CABG (n=453). There was no difference in deaths. In the nonrestenotic PTCA group, the incidence of more infarctions was insignificant (relative risk [RR] 1.9, 95% confidence intervals [CI] 0.96 to 3.75, p=0.064), there was a much greater need for repeat revascularization (RR 8.6, CI 5.14 to 14.41, p <0.0005), and patients had a poorer angina status (RR 1.46, CI 1.01 to 2.13, p=0.046). Using 2 measures of coronary disease, the degree of pre- and postrevascularization disease was compared between groups. There were no differences in prerevascularization disease. However, using either measure, residual postrevascularization disease was more frequent in the nonrestenotic PTCA group. Restenosis only partially accounts for the greater morbidity seen after PTCA, compared with CABG, in multivessel disease. The greater likelihood of residual disease post-PTCA may contribute to this greater morbidity.

Adult↗
PubMed1998

Differential restenosis rate of individual coronary artery sites after multivessel angioplasty: implications for revascularization strategy. CABRI Investigators. Coronary Angioplasty versus Bypass Revascularisation Investigation.

BACKGROUND: Restenosis is a major limitation of angioplasty. In this analysis we assessed the effects of lesion site and quality of dilatation on restenosis rate in the Coronary Angioplasty versus Bypass Revascularization Investigation population who underwent angioplasty. METHODS: The angiographic quality of the successful angioplasty revascularization at each site was assessed, and the subsequent restenosis rate was determined. Restenosis was defined by the need for a second angioplasty at the initial site or by surgical coronary bypass grafting at or distal to the initial site. RESULTS: The restenosis rate was unaffected by quality of dilatation but was significantly more common in the proximal left anterior descending artery compared with other sites, whether or not optimal dilatation had been achieved (relative risk 2.0 and 1.9, respectively). CONCLUSION: Revascularization strategies in multivessel disease should consider the presence or absence of a proximal left anterior descending artery target. Furthermore in studies in which restenosis is an outcome of interest, an allowance should be made for the distribution of target disease.

Aged↗
PubMed1996

A British Cardiac Society survey of the potential for the secondary prevention of coronary disease: ASPIRE (Action on Secondary Prevention through Intervention to Reduce Events).

OBJECTIVE: To measure the potential for secondary prevention of coronary disease in the United Kingdom. DESIGN: Cross sectional survey of a representative sample of coronary patients from a retrospective review of hospital medical records and patient interview and examination. SETTING: Stratified random sample of 12 specialist cardiac centres and 12 district general hospitals drawn from 34 specialist cardiac centres and 261 district general hospitals in 12 geographic areas in the United Kingdom. SUBJECTS: 2583 patients < or = 70 yr; 25 consecutive males and 25 consecutive females identified retrospectively in each of four diagnostic categories: coronary artery bypass grafting, percutaneous transluminal coronary angioplasty, acute myocardial infarction, and acute myocardial ischaemia without evidence of infarction. MAIN OUTCOME MEASURES: Risk factor recording and management in medical records; the prevalence and control of risk factors at interview six months after the procedure or event. RESULTS: Recording of coronary risk factors in patient's records was incomplete and this varied by risk factor. Smoking habit and blood pressure were most completely recorded, whereas a history of hyperlipidaemia and blood cholesterol concentrations were least complete. Risk factor records were more likely to be complete in cardiac centres than in district hospitals. At interview 10% to 27% of patients were still smoking cigarettes and 75% remained overweight, females more severely so. Up to a quarter of patients remained hypertensive, males more severely so than females. Over three quarters had a total cholesterol > 5.2 mmol/l. In patients on medication for blood pressure, cholesterol or glucose, risk factor profiles were little better than in those who were not. Only about one patient in three was taking a beta blocker after infarction. Up to a fifth of patients who had had acute myocardial ischaemia were not taking aspirin at follow up. CONCLUSIONS: There is considerable potential to reduce the risk of a further major ischaemic event in patients with established coronary disease. This can be achieved by effective lifestyle intervention, the rigorous management of blood pressure and cholesterol, and the appropriate use of prophylactic drugs.

Adrenergic beta-Antagonists↗
PubMed1995

Sudden unexpected cardiac death: methods and results of a national pilot survey.

In order to develop a methodology for measuring the occurrence and circumstances of sudden unexpected adult deaths due to cardiac and to unidentified causes throughout England, a stratified random pilot sample of 12 of the 133 coroner's jurisdictions in England was invited to survey prospectively a quota sample of 78 consecutive white Caucasians, aged from 16 to 64 years, with no history of ischaemic heart disease, who were last seen alive within 12 h of being found dead, and for whom a coroner's post-mortem examination found either a cardiac or no identifiable cause of death. Eleven (92%) coroners participated. In a median of 105 days (range 21-169), 65 cases (83% of the quota) were ascertained (54 (83%) males). Of the ascertained cases, registration forms were received on 62 (95%), tissue specimens on 63 (97%), and post-mortem reports on 58 (89%). Death was witnessed in 58%, of which 35% were 'instantaneous'. The median time from symptom onset to death was 40 min. In unwitnessed deaths, the median time since last being seen alive was 90 min. Sixty-eight per cent of all deaths were attended--by a relative in 34%, passer-by (8%), ambulance crew (32%), nurse (11%), doctor (38%), and police (9%). Cardio-pulmonary resuscitation was attempted in 38 of the 42 attended deaths. Sixty-seven per cent were taken ill at home, 12% at work, 12% in a public place, and 10% elsewhere. The certified cause of death was ischaemic heart disease in 89%, in whom coronary thrombosis and/or myocardial damage was absent in 6 cases (9%). In the remainder, the certified cause was hypertensive heart disease (5%), hypertrophic obstructive cardiomyopathy (3%), 'cardiomegaly' (1.5%) and 'sudden cardiac arrhythmia' alone (1.5%). A retrospective audit of coroner's records revealed the median case ascertainment rate was 75%. This approach to surveying sudden unexpected adult death nationally resulted in a high response rate (92%) from coroners, consultant pathologists and their staff, the identification of a large proportion of eligible cases, and complete information in most of the identified cases. In from 2% to 15% of cases, death may have been either purely dysrhythmic or due to a sudden adult death syndrome.

Adolescent↗