Biomedical subjects

P D Batin

Publications and source records attributed to P D Batin.

9 recordsLinked to original sources

PubMed2004

Predicting sudden death in patients with mild to moderate chronic heart failure.

OBJECTIVES: To explore the relation between non-invasive measures of cardiac function and sudden cardiac death, as well as the development and utility of an index integrating these variables to identify patients at increased risk of this mode of death. DESIGN: UK-HEART (United Kingdom-heart failure evaluation and assessment of risk trial) was a prospective study conducted between December 1993 and April 2000. The study was specifically designed to identify non-invasive markers of death and mode of death among patients with chronic heart failure. SETTING: 8 UK general hospitals. MAIN OUTCOME MEASURES: Death and mode of death. RESULTS: 553 patients aged a mean (SD) of 63 (10) years, in New York Heart Association functional class 2.3 (0.02), recruited prospectively. After 2365 patient-years' follow up, 201 patients had died (67 suddenly). Predictors of sudden death were greater cardiothoracic ratio, QRS dispersion, QT dispersion corrected for rate (QTc) across leads V1-V6 on the 12 lead ECG, and the presence of non-sustained ventricular tachycardia. The hazard ratio and 95% confidence intervals (CI) of sudden death for a 10% increase in cardiothoracic ratio was 1.43 (95% CI 1.20 to 1.71), for a 10% increase in QRS dispersion 1.11 (95% CI 1.04 to 1.19), for the presence of non-sustained ventricular tachycardia 2.03 (95% CI 1.27 to 3.25), and for a 10% increase in QTc dispersion across leads V1-V6 1.03 (95% CI 1.00 to 1.07) (all p < 0.04). An index derived from these four factors performed well in identifying patients specifically at increased risk of sudden death. CONCLUSIONS: Results show that an index derived from three widely available non-invasive investigations has the potential to identify ambulant patients with chronic heart failure at increased risk of sudden death. This predictive tool could be used to target more sophisticated investigations or interventions aimed at preventing sudden death.

Aged↗

PubMed2000

Antiarrhythmic management and implantable defibrillator use in survivors of prehospital cardiac arrest without myocardial infarction in West Yorkshire.

OBJECTIVE: To explore the current use of secondary preventive treatment in survivors of out of hospital cardiac arrest without myocardial infarction (primary ventricular tachycardia/ventricular fibrillation (VT/VF)) in West Yorkshire, and assess the implications of recent studies on the benefits of implantable cardioverter-defibrillators (AICD) in this context. DESIGN: Retrospective analysis of an ambulance service based database of outcome after resuscitation of out of hospital cardiac arrest and the Leeds AICD implantation database. MAIN OUTCOME MEASURES: Mortality, rate of referral for specialist investigation, antiarrhythmic treatment. RESULTS: Twelve month mortality following successful discharge after primary VF arrest was 15%. Of 53 patients with primary VF/VT, 29 apparently did not see a cardiologist during the initial admission. Amiodarone was the most widely used antiarrhythmic agent. Six patients (15%) received an AICD. During the same period 22 patients from the same catchment area received an AICD following an in-hospital cardiac arrest. CONCLUSIONS: Mortality among survivors of non-infarct related prehospital cardiac arrest remains significant, with few patients being referred for specialist investigation. The implementation of recent guidelines on AICD use in cardiac arrest survivors would have resulted in an approximate 60% increase in the total numbers of defibrillators implanted in the West Yorkshire area.

Adult↗

PubMed1999

The relationship between QT intervals and mortality in ambulant patients with chronic heart failure. The united kingdom heart failure evaluation and assessment of risk trial (UK-HEART)

AIMS: Mortality in patients with heart failure remains high and is difficult to predict. QT interval parameters on a 12-lead ECG have been shown to predict arrhythmic events in patients with a variety of myocardial diseases. There is some, but not consistent, evidence that QT interval parameters may act as predictors of mortality, in particular sudden death, in patients with heart failure. In an adequately powered prospective study we have studied QT interval parameters in patients with stable chronic heart failure in order to determine whether they are predictive of all-cause mortality or mode of death. METHODS AND RESULTS: Five hundred and fifty-four ambulant outpatients with chronic heart failure were recruited. A 12-lead ECG, chest radiograph, echocardiogram, 24 h ambulatory electrocardiogram and serum for biochemical analysis were obtained at baseline. Patients were followed for 471+/-168 days. QT intervals were measured in all leads blinded to patient's characteristics and outcome, were corrected for heart rate, and the maximum QT intervals, and QT dispersion (range of QT intervals) were determined. The same parameters were determined for JT intervals. The primary end-point was all-cause mortality, secondary end-points were sudden cardiac death and death due to progressive heart failure. Multivariate analysis with the Cox's proportional hazards model was used to determine which variables were independently related to outcome. Four hundred and ninety-five patients had analysable ECGs at study entry and of these 71 died during follow-up. The heart rate corrected QT dispersion and maximum QT interval were significant univariate predictors of all-cause mortality (P=0.026 and <0.0001 respectively), and also of sudden death and progressive heart failure death, but were not related to outcome in the multivariate analysis. The independent predictors of all-cause mortality were cardiothoracic ratio (P=0.0003), creatinine (P=0.0009), heart rate (P=0.007), echocardiographically derived left ventricular end-diastolic dimension (P=0.007) and ventricular couplets on 24 h electrocardiographic monitoring (P=0.015). CONCLUSION: In an adequately powered prospective study none of the QT or JT parameters were shown to be independent predictors of outcome in patients with mild to moderate congestive heart failure. These variables do not therefore add to the prognostic information which can be gained from simple radiographic, biochemical, echocardiographic and Holter data in this group of patients.

Death, Sudden, Cardiac↗

PubMed1999

Ventricular dilatation in the absence of ACE inhibitors: influence of haemodynamic and neurohormonal variables following myocardial infarction.

OBJECTIVE: To examine the relation between patterns of ventricular remodelling and haemodynamic and neurohormonal variables, at rest and during symptom limited exercise, in the year following acute myocardial infarction in patients not receiving angiotensin converting enzyme (ACE) inhibitors. DESIGN: A prospective observational study. PATIENTS: 65 patients recruited following hospital admission with a transmural anterior myocardial infarction. METHODS: Central haemodynamics and neurohormonal activation at rest and during symptom limited treadmill exercise were measured at baseline before hospital discharge, one month later, and at three monthly intervals thereafter. PATIENTS were classified according to individual patterns of change in left ventricular end diastolic volumes at rest, assessed at each visit using transthoracic echocardiography. RESULTS: In most patients (n = 43, 66%) ventricular volumes were unchanged or reduced. Mean (SEM) treadmill exercise capacity and peak exercise cardiac index increased at month 12 by 200 (24) seconds (p < 0.001 v baseline) and by 0.8 (0.4) l/min/m2 (p<0.05 v baseline), respectively, in this group. In patients with limited ventricular dilatation (n = 11, 17%) exercise capacity increased by 259 (52) seconds (p < 0.001 v baseline) and peak exercise cardiac index improved by 0.8 (0.7) l/min/m2 (NS). In the remaining 11 patients with progressive left ventricular dilatation, exercise capacity increased by 308 (53) seconds (p< 0. 001 v baseline) and peak exercise cardiac index similarly improved by 1.3 (0.7) l/min/m2 (NS). There were trends towards increased atrial natriuretic factor (ANF) secretion at rest and at peak exercise in this group. CONCLUSIONS: Ventricular dilatation after acute myocardial infarction is a heterogeneous process that is progressive in only a minority of patients. Compensatory mechanisms, including ANF release, appear capable of maintaining and improving exercise capacity in most patients for at least 12 months, even in those with a progressive increase in ventricular size.

Adult↗

PubMed1998

Prospective study of heart rate variability and mortality in chronic heart failure: results of the United Kingdom heart failure evaluation and assessment of risk trial (UK-heart).

BACKGROUND: Patients with chronic heart failure (CHF) have a continuing high mortality. Autonomic dysfunction may play an important role in the pathophysiology of cardiac death in CHF. UK-HEART examined the value of heart rate variability (HRV) measures as independent predictors of death in CHF. METHODS AND RESULTS: In a prospective study powered for mortality, we recruited 433 outpatients 62+/-9.6 years old with CHF (NYHA functional class I to III; mean ejection fraction, 0.41+/-0.17). Time-domain HRV indices and conventional prognostic indicators were related to death by multivariate analysis. During 482+/-161 days of follow-up, cardiothoracic ratio, SDNN, left ventricular end-systolic diameter, and serum sodium were significant predictors of all-cause mortality. The risk ratio for a 41.2-ms decrease in SDNN was 1.62 (95% CI, 1.16 to 2.44). The annual mortality rate for the study population in SDNN subgroups was 5.5% for >100 ms, 12.7% for 50 to 100 ms, and 51.4% for <50 ms. SDNN, creatinine, and serum sodium were related to progressive heart failure death. Cardiothoracic ratio, left ventricular end-diastolic diameter, the presence of nonsustained ventricular tachycardia, and serum potassium were related to sudden cardiac death. A reduction in SDNN was the most powerful predictor of the risk of death due to progressive heart failure. CONCLUSIONS: CHF is associated with autonomic dysfunction, which can be quantified by measuring HRV. A reduction in SDNN identifies patients at high risk of death and is a better predictor of death due to progressive heart failure than other conventional clinical measurements. High-risk subgroups identified by this measurement are candidates for additional therapy after prescription of an ACE inhibitor.

Aged↗

PubMed1995

Haemodynamic and hormonal response to a stream of cooled air.

Many patients with angina note that their symptoms deteriorate in cold weather, although the precise physiological mechanism that explains this remains unclear. Exposure of the face to cool winds may be a contributory factor. The cardiovascular and hormonal response to a localised stream of room (22 degrees C) and cold (4 degrees C) air during submaximal treadmill exercise was therefore studied in nine normal subjects. Cardiac output and respiratory gases were measured with a mass spectrometer, using the indirect Fick principle. Blood samples were taken for plasma noradrenaline. A localised stream of air at 5 m.s-1 produced significant cardiovascular effects at rest, some of which persisted during exercise. In response to cold air, stroke volume, cardiac output, blood pressure and oxygen uptake increased (all P < 0.05). There was a trend towards a reduction in heart rate at rest and increase in plasma noradrenaline. Room air caused a reduction in blood pressure (P = 0.01) but stroke volumes and oxygen uptake were unchanged. The results of this study demonstrate significant cardiovascular effects of a cooled air facial stimulus at rest and during exercise. They may, in part, explain the effects of cold winds on patients with angina.

Adult↗

PubMed1994

Patterns of neuroendocrine activation at rest and during exercise following acute myocardial infarction.

Previous studies of neurohumoral activation following myocardial infarction have concentrated on the within-hospital phase and have only made measurements at rest. The objectives of this study were to measure neuroendocrine activity in the early convalescent phase of myocardial infarction at rest and during symptom-limited maximal exercise and to study the effects of early drug therapy. We studied 75 patients, mean age 57 (range 37-74) without evidence of overt heart failure, following Q-wave myocardial infarction. Patients were studied a mean of 17 days following myocardial infarction and compared with 11 age-matched control subjects. Plasma noradrenaline, adrenaline, atrial natriuretic peptide and plasma renin activity were measured at rest, at submaximal and symptom-limited maximal treadmill exercise. At the time of study 40 patients were taking beta-blockers, 19 diuretics and 16 no treatment. Atrial natriuretic peptide levels were higher at rest (P = 0.0001) and at symptom-limited exercise (P = 0.002) in the patient group than in the control subjects. Although there were no significant resting differences between the patient subgroups, at symptom-limited exercise plasma atrial natriuretic peptide levels were significantly higher in the patients taking beta-blockers than in the other patient groups (P = 0.001). Plasma renin activity was no different between the patients and the control subjects at rest or during exercise. Those patients taking diuretics had higher values at rest (P = 0.001) and during exercise (P = 0.005) compared with the remaining patients. There were no significant differences in resting or maximal exercise levels of plasma noradrenaline and adrenaline between the patients and the control subjects (all P > 0.1).(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenergic beta-Antagonists↗

PubMedDate not supplied

Management and health status in the first year after out-of-hospital cardiac arrest.

The one-year survival, functional and cerebral capacity and patient management following out-of-hospital cardiac arrest were examined in a follow-up study of 143 prospectively identified patients discharged from a West Yorkshire hospital between January 1987 and July 1993. One-year survival was 87%; 13 of the 18 deaths were cardiac related; 89% of survivors had no further cardiac related admissions; 98% of patients surviving to one year were capable of independent daily activities. There was low utilisation of simple drug therapy: 23% of patients were discharged taking beta-blockers and 52% aspirin; 50% of patients discharged after a primary arrhythmic event were taking antiarrhythmic therapy or were given an implantable defibrillator. Irrespective of the availability of invasive cardiac facilities, there was underutilisation of investigations: only 39% of patients were seen by a cardiologist and 54% were not evaluated for ischaemic risk. Significant improvements in patient management could probably be achieved quickly without substantial increases in resources.

Adolescent↗

PubMedDate not supplied

Junior doctors and clinical audit.

OBJECTIVES: To assess the extent of junior doctor involvement in clinical audit, the degree of support from audit staff, and the perceived value of the resulting audits. DESIGN: Postal survey of National Health Service (NHS) junior doctors. SUBJECTS AND SETTINGS: 704 junior doctors in central Leeds hospitals, June 1996. RESULTS: Questionnaires were returned by 232 respondents (33%), 211 (31%) were completed; 157 respondents (74%) had personally performed audit. Mean (+/- SD) duration since last audit project was 14.9 (14.1) (range 0-84) months. Of the respondents who had personally performed audit, 88 (56%) did not use the hospital audit department, 60 (38%) received no guidance and only 19 (12%) were involved in re-auditing the same project. Mean (+/- SD) time spent per audit project was 27.8 (37.7), (range 2-212) hours. Seventy-five junior doctors (48%) were aware of subsequent change in clinical practice, 41 (26%) perceived a negative personal benefit from audit, 33 (21%) perceived a negative departmental benefit, and 42 (27%) felt that audit was a waste of time. CONCLUSIONS: A large proportion of junior doctors are involved in audit projects that do not conform to established good practice and which have a low impact on clinical behaviour. Although junior doctors feel that there is inadequate assistance and poor supervision whilst performing audit, they still support the principle of audit. There is a need to improve the quality and supervision of audit projects performed by junior doctors.

Attitude of Health Personnel↗