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J Poloniecki

Publications and source records attributed to J Poloniecki.

At least 19 recordsLinked to original sources
PubMed1996

Distinction between arrhythmic and nonarrhythmic death after acute myocardial infarction based on heart rate variability, signal-averaged electrocardiogram, ventricular arrhythmias and left ventricular ejection fraction.

OBJECTIVES: We investigated whether heart rate variability, the signal-averaged electrocardiogram (ECG), ventricular arrhythmias and left ventricular ejection fraction predict the mechanism of cardiac death after myocardial infarction. BACKGROUND: Postinfarction risk stratification studies have almost exclusively focused on predicting the risk of arrhythmic death. The factors that identify and distinguish persons at risk for arrhythmic and nonarrhythmic death are poorly known. METHODS: Heart rate variability, the signal-averaged ECG, ventricular arrhythmias and left ventricular ejection fraction were assessed in 575 survivors of acute myocardial infarction. The patients were followed up for 2 years; arrhythmic and nonarrhythmic cardiac deaths were used as clinical end points. During the follow-up period, 47 cardiac deaths occurred, 29 (62%) arrhythmic and 18 (38%) nonarrhythmic. RESULTS: All risk factors were associated with cardiac mortality in univariate analysis. With the exception of left ventricular ejection fraction, they were also predictors of arrhythmic death. Depressed heart rate variability (p < 0.001), ventricular ectopic beats (p < 0.001) and low ejection fraction (p < 0.001) were related to nonarrhythmic death. In multivariate analysis, depressed heart rate variability (p < 0.001) and runs of ventricular tachycardia (p < 0.05) predicted arrhythmic death. Nonarrhythmic death was associated with depressed heart rate variability (p < 0.001), ventricular ectopic beats (p < 0.001) and low ejection fraction (p < 0.01). By selecting patients with depressed heart rate variability, long filtered QRS duration or ventricular arrhythmias and excluding patients with the lowest ejection fraction, we identified a group in which 75% of deaths were arrhythmic. Similarly, by selecting patients with a low ejection fraction and excluding patients with the lowest heart rate variability, we identified a group in which 75% of deaths were nonarrhythmic. CONCLUSIONS: Arrhythmic death was associated predominantly with depressed heart rate variability and ventricular tachycardia runs, and nonarrhythmic death with low ejection fraction, ventricular ectopic beats and depressed heart rate variability. A combination of risk factors identified patient groups in which a majority of deaths were either arrhythmic or nonarrhythmic.

Electrocardiography↗
PubMed1995

Using data from the 1991 census.

The 1991 census for England and Wales provides a substantial amount of data on demography, ethnicity, housing tenure, employment status, and other social factors for geographical areas ranging in size from enumeration districts upwards. Many in the health service and in the academic community are making use of the data in the 1991 census. However, users of census data need to be aware of the problems and limitations of these data, which include the format of the data, data modification and suppression, sampling error, and underenumeration. An important innovation of the 1991 census was that the census form included a question on the postcode of respondents; this allowed the Office of Population Censuses and Surveys to produce a postcode-enumeration district look up table which overcomes many of the problems previously encountered in trying to assign postcodes to enumeration districts. The new look up table also includes the grid reference of postcodes, and this will improve the geographical referencing of census data.

Data Collection↗
PubMed1995

Differential progression of complex and smooth stenoses within the same coronary tree in men with stable coronary artery disease.

OBJECTIVES: We sought to compare the evolution of complex and smooth stenoses within the same coronary tree in patients with stable coronary artery disease. BACKGROUND: Progression of coronary stenosis has prognostic significance and may be influenced by local and systemic factors. Stenosis morphology is a determinant of disease progression, but no previous study has systematically assessed progression of complex and smooth stenoses within the same patient. METHODS: We studied 50 men with stable angina who 1) had one complex coronary stenosis and one smooth stenosis in different noninfarct-related coronary vessels at initial coronary angiography, and 2) had a second angiogram after a median interval of 9 months (range 3 to 24). Patients with lesions > or = 10 mm long, at a major branching point or with > 85% diameter reduction were not included. Coronary lesions were measured quantitatively from comparable end-diastolic frames. Stenosis morphology was determined qualitatively by two independent observers. RESULTS: All patients remained in stable condition during follow-up. Progression, defined as an increase in diameter stenosis by > or = 15% was seen in only eight complex stenosis (16%) but in no smooth lesions (p < 0.01). The severity of complex stenoses changed more than that of corresponding smooth stenoses (mean +/- 1 SD 5.8 +/- 13% vs. -0.06 +/- 6%, p < 0.01). On average, the annual rate of growth was 11.4 +/- 28% and 1.5 +/- 14% for complex and smooth lesions, respectively (p < 0.01). CONCLUSIONS: Few coronary stenoses progress rapidly in stable angina. Complex and smooth coronary stenoses progress at different rates within the same coronary tree. complex stenosis morphology itself is an important determinant of progression of stenosis in patients with apparently clinically stable coronary artery disease.

Aged↗
PubMed1995

Prognostic significance of spectral turbulence analysis of the signal-averaged electrocardiogram in patients with idiopathic dilated cardiomyopathy.

The aim of this study was to assess whether spectral turbulence analysis (STA) of the signal-averaged electrocardiogram (SAECG) is of prognostic use in patients with idiopathic dilated cardiomyopathy. SAECGs were recorded at presentation in 84 patients with idiopathic dilated cardiomyopathy and STA was performed using 183 Del Mar software. STA was abnormal (> or = 3 of the 4 standard parameters beyond the normal range) in 31 patients (37%). Patients were followed for a mean duration of 24 +/- 18 months (range 1 to 59) during which time 24 (29%) developed progressive heart failure (14 underwent cardiac transplantation), 4 died suddenly or had aborted sudden death, and the others remained clinically stable. Progressive heart failure occurred more often in patients who had an abnormal versus a normal STA result (15 [48%] vs 9 [17%]; p < 0.002). Actuarial survival revealed a 1-year survival of 90% in patients with a normal STA result, and 63% in patients with an abnormal STA result (p < 0.01). The predictive ability of STA to identify patients with progressive heart failure was sensitivity 63%, specificity 77%, positive predictive value 54%, and negative predictive value 83%. Univariate analysis identified peak oxygen consumption as having the largest relative risk for the development of progressive heart failure (9.55, 95% confidence interval [CI] 2.1 to 43.9). Left ventricular end-diastolic dimension (relative risk 4.18, 95% CI 1.5 to 11.4) and STA (relative risk 3.81, 95% CI 1.7 to 8.8) were also significantly associated with the development of progressive heart failure.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Resternotomy for bleeding after cardiac operation: a marker for increased morbidity and mortality.

Over a 2-year period from January 1, 1992, to December 31, 1993, of 2,221 patients undergoing cardiac operations in our unit, 85 (3.8%) were reopened for the control of bleeding (9 patients more than once). The incidence of resternotomy in coronary cases was 2.3%, but resternotomy was more than three times as likely in valve cases (odds ratio, 3.4; 95% confidence interval, 2.1 to 5.4). Previous cardiac operation was more common among resternotomy patients than among the remainder (18% versus 9%, respectively; p = 0.018). An identifiable source of bleeding was found in 57 of the 85 patients (67%), but a concurrent coagulopathy was common (45 patients). Resternotomy patients, as a group, had higher preoperative risk scores (Parsonnet) than did the other patients (p < 0.0001), stayed longer in the intensive care unit (p < 0.0001), and had greater requirements for intraaortic balloon counterpulsation (14% versus 3%) and hemofiltration (9% versus 3%) (p < 0.0001 and p < 0.01, respectively). Nineteen resternotomy patients (22%) died in the hospital, a proportion significantly greater than the risk assigned to this group of patients preoperatively (12.8%) (p = 0.008). In contrast, the observed mortality for the other 2,136 patients (5.5%) was significantly less (8.3%) (p < 0.00006). Multiple forward stepwise logistic-regression analysis confirmed resternotomy for excessive bleeding after cardiac operation to be a significant independent predictor of a prolonged stay in the intensive care unit (p < 0.0001), the need for intraaortic balloon counterpulsation (p < 0.0001), and death (p < 0.0001).

Aged↗
PubMed1995

Effect of flecainide on atrial and ventricular refractoriness and conduction in patients with normal left ventricle. Implications for possible antiarrhythmic and proarrhythmic mechanisms.

We studied the effects of intravenous flecainide (2 mg.kg-1) on atrial and ventricular refractoriness and conduction during sinus rhythm, induced atrial fibrillation and atrial pacing at rates of 100, 120 and 150 ppm, in 14 patients with normal left ventricle. Flecainide caused a significant increase in QRS duration during sinus rhythm (mean +/- SD: 87.2 +/- 8.4 ms vs 102.8 +/- 9.1 ms, P < 0.001), atrial fibrillation (87.8 +/- 10.0 ms vs 108.8 +/- 13.7 ms, P < 0.001) and at all paced rates. The duration of the atrial electrogram was significantly increased during sinus rhythm (54.9 +/- 13.2 ms vs 64.8 +/- 16.6 ms, P = 0.003) and at all pacing rates. The PA interval was also significantly prolonged, as was the pacing stimulus-to-atrial-electrogram interval at all pacing rates. There was increased QRS duration and atrial electrogram prolongation at higher pacing rates. Atrial refractoriness was prolonged during sinus rhythm (216.4 +/- 28.2 vs 228.6 +/- 36.1, P = 0.02), but not during atrial pacing at any rate. The QT interval, but not the JT interval or ventricular refractoriness, was significantly prolonged during sinus rhythm and at all pacing rates. Flecainide slows atrial conduction in a use dependent manner and increases atrial refractoriness during sinus rhythm but not during faster atrial pacing, thus not displaying a use-dependent effect. QRS duration is prolonged in a use-dependent manner without a commensurate increase in ventricular refractoriness. In the presence of rapidly conducted atrial fibrillation, which was not found to be slowed by flecainide, this effect may constitute a proarrhythmic mechanism even in patients with no apparent myocardial abnormality.

Adult↗
PubMed1995

Do general practitioners influence the uptake of breast cancer screening?

OBJECTIVES: To investigate the relative importance of patient and general practice characteristics in explaining variations between practices in the uptake of breast cancer screening. DESIGN: Ecological study examining variations in breast cancer screening rates among 131 general practices using routine data. SETTING: Merton, Sutton, and Wandsworth Family Health Services Authority, which covers parts of inner and outer London. MAIN OUTCOME MEASURE: Percentage of eligible women aged 50-64 who attended for mammography during the first round of screening for breast cancer (1991-1994). RESULTS: Of the 43,063 women eligible for breast cancer screening, 25,826 (60%) attended for a mammogram. Breast cancer screening rates in individual practices varied from 12.5% to 84.5%. The estimated percentage list inflation for the practices was the variable most highly correlated with screening rates (r = -0.69). There were also strong negative correlations between screening rates and variables associated with social deprivation, such as the estimated percentage of the practice population living in households without a car (r = -0.61), and with variables that measured the ethnic make-up of practice populations, such as the estimated percentage of people in non-white ethnic groups (r = -0.60). Screening rates were significantly higher in practices with a computer than in those without (59.5% v 53.9%, difference 5.6%, 95% confidence interval 1.1 to 10.2%). There was no significant difference in screening rates between practices with and without a female partner; with and without a practice nurse; and with and without a practice manager. In a forward stepwise multiple regression model that explained 58% of the variation in breast cancer screening rates, four factors were significant independent predictors (at P = 0.05) of screening rates: list inflation and people living in households without a car were both negative predictors of screening rates, and chronic illness and the number of partners in a practice were both positive predictors of screening rates. The practice with the highest screening rate (84.5%) contacted all women invited for screening to encourage them to attend for their mammogram and achieved a rate 38% higher than predicted from the regression model. Breast cancer screening rates were on average lower than cervical cancer screening rates (mean difference 14.5%, standard deviation 12.0%) and were less strongly associated with practice characteristics. CONCLUSIONS: The strong negative correlation between breast cancer screening rates and list inflation shows the importance of accurate age-sex registers in achieving high breast cancer screening rates. Breast cancer screening units, family health services authorities, and general practitioners need to collaborate to improve the accuracy of the age-sex registers used to generate invitations for breast cancer screening. The success of the practice with the highest screening rate suggests that practices can influence the uptake of breast cancer screening among their patients. Giving general practitioners a greater role in breast cancer screening, either by offering them financial incentives or by giving them clerical support to check prior notification lists and contact nonattenders, may also help to increase breast cancer screening rates.

Breast Neoplasms↗
PubMed1995

Annual night visiting rates in 129 general practices in one family health services authority: association with patient and general practice characteristics.

BACKGROUND: Rates of night visiting by general practitioners have increased steadily over the last 30 years and vary widely between general practices. AIM: An ecological study was carried out to examine night visiting rates by general practices in one family health services authority, and to determine the extent to which differences in night visiting rates between practices could be explained by patient and practice characteristics. METHOD: The study examined the variation in annual night visiting rates, based on night visit fees claimed between April 1993 and March 1994, among 129 general practices in Merton, Sutton and Wandsworth Family Health Services Authority, London. RESULTS: Practices' annual night visiting rates varied from three per 1000 to 75 per 1000 patients. The percentages of the practice population aged under five years and aged five to 14 years were both positively correlated with night visiting rates (r = 0.38 and r = 0.35, respectively), as were variables associated with social deprivation such as the estimated percentage of the practice population living in one-parent households (r = 0.24) and in households where the head of household was classified as unskilled (r = 0.20). The percentage of the practice population reporting chronic illness was also positively associated with night visiting rates (r = 0.26). The percentages of the practice population aged 35 to 44 years and 45 to 54 years were both negatively associated with night visiting rates (r = -0.34 and r = -0.31, respectively) as was the estimated list inflation for a practice (r = -0.31). There was no significant correlation between night visiting rates and the distance of the main practice surgery from the nearest hospital accident and emergency department. There was also no association between night visiting rates and permission to use a deputizing service. In a stepwise multiple regression model, the multiple correlation coefficient was 0.56 with four factors (percentage of the practice population aged under five years, percentage aged 35-44 years, percentage who were chronically ill and estimated list inflation) explaining 32% of the variation in night visiting rates. CONCLUSION: Only about one third of the variation in night visiting rates between practices could be explained by patient and practice variables derived from routine data. Population-based research using data collected on individual patients and practices is required to improve current understanding of the patient and practice characteristics that influence the demand for night visits and of why night visiting rates vary so widely between practices.

Adolescent↗
PubMed1994

Change of autonomic influence on the heart immediately before the onset of spontaneous idiopathic ventricular tachycardia.

OBJECTIVES: This study aimed to assess heart rate variability immediately before the onset of episodes of spontaneous ventricular tachycardia. BACKGROUND: It has been shown that decreased heart rate variability may be associated with a propensity to ventricular tachyarrhythmias. However, it is still disputed whether there is an abrupt change in heart rate variability immediately before the onset of these arrhythmias. METHODS: Twenty-three patients with idiopathic ventricular tachycardia underwent two-channel 24-h Holter monitoring in a drug-free state. Spectral heart rate variability was computed as low (0.04 to 0.15 Hz) and high (0.15 to 0.40 Hz) frequency components at 2-min intervals over a 1-h period immediately before the onset of ventricular tachycardia. Average values of heart rate variability were also computed for the entire 24-h recordings. The low/high frequency component ratio was calculated as an index of the autonomic balance of the heart. RESULTS: Seventy-one episodes of ventricular tachycardia from the 23 recordings formed this study. There was an increased low/high ratio during 6- to 8-min periods immediately before the onset of ventricular tachycardia episodes compared with the average values for the entire 24 h. This increase in the low/high ratio resulted largely from a decrease in the high frequency component value (4.70 +/- 1.15 vs. 5.10 +/- 1.06 ln[ms2] [mean +/- SD], p = 0.001) because there was no significant change in the low frequency component value (6.37 +/- 1.20 vs. 6.34 +/- 0.91 ln[ms2], p = 0.786, 95% confidence interval -0.25 to 0.19 ln[ms2], type II error < 0.0001 for change of 7.8%). In contrast, there were no significant differences in the low or high frequency components or low/high ratio between 6-min salvo-free periods 40 min before the onset of ventricular tachycardia and the average 24-h values (type II error < 0.0001, < 0.038 and < 0.1841, respectively, for change of 7.8%). The low/high ratio was also significantly higher during the 6 min immediately before the onset of ventricular tachycardia compared with that during the 6-min salvo-free periods 40 min before the onset of ventricular tachycardia. A significant increase in mean heart rate immediately before the onset of ventricular tachycardia was also noted. CONCLUSIONS: There is a significant change in autonomic influence on the heart during the last few minutes preceding the onset of episodes of idiopathic ventricular tachycardia. This seems to result mainly from decreased vagal activity rather than enhanced sympathetic input to the heart.

Adolescent↗
PubMed1994

A prospective case-control study of antibodies to coxsackie B virus in idiopathic dilated cardiomyopathy.

OBJECTIVES: This study was conducted to determine the frequency and significance of Coxsackie B virus-specific immunoglobulin-M (IgM) in patients with idiopathic dilated cardiomyopathy and compare them with the frequency in both unmatched and matched control subjects. BACKGROUND: The principal evidence supporting a pathoetiologic role for Coxsackie B viruses in human dilated cardiomyopathy is derived from retrospective serologic studies. These studies have evaluated patients with end-stage disease and have failed to recognize the importance of assessing both matched and unmatched control subjects. METHODS: In this prospective case-control study, we assessed sera for Coxsackie B virus-specific IgM (serotypes B1 to B5) from 114 patients with dilated cardiomyopathy at diagnosis or referral to our center, 94 healthy unmatched control subjects, 41 healthy matched control subjects from the same general practitioner and 32 members of the patients' own households. RESULTS: A higher frequency of positive Coxsackie B virus IgM was observed in patients with dilated cardiomyopathy than in unmatched control subjects (33% vs. 5%; p = 3 x 10(-7)). In patients with dilated cardiomyopathy, the response was monotypic (84%), commonly against serotypes B2 and B5, and was not associated with any clinical or histologic feature. The frequency of positive virus-specific IgM was similar in patients with dilated cardiomyopathy and their 41 matched community control subjects (46% vs. 27%; p = 0.11) and 32 household contacts (37% vs. 28%; p = 0.59). Control subjects who tested positive for virus-specific IgM tended more commonly to be seropositive than did control seronegative subjects (community control subjects 37% vs. 18%, p = 0.32; household contacts 42% vs. 20%; p = 0.36) and had an identical serotypic response in 4 (33%) of 12 cases. CONCLUSIONS: The frequency of Coxsackie B virus IgM was higher in patients with dilated cardiomyopathy than in unmatched control subjects but was similar in patients and control subjects who shared the same environment, indicating local spread of infection. The reason for the association between Coxsackie B virus IgM and dilated cardiomyopathy and its relevance to pathogenesis remain to be established.

Adult↗
PubMed1994

Radiofrequency ablation of accessory pathways: implications of accumulated experience and time dedicated to procedures.

Previous reports on radiofrequency ablation of accessory pathways have shown that the experience of the operator is of crucial importance in reducing fluoroscopy time and achieving higher success rates. However, a detailed analysis of this important issue has not been previously attempted. We analysed 71 consecutive ablation procedures undertaken at St George's Hospital by the same electrophysiology group and always with the same first operator. Of all procedures, 66 (91.6%) were successful, as judged by abolition of accessory pathway conduction without recurrence within the next 24 h. Failures included two out of 38 left-sided pathway procedures (5.3%), one out of 11 intermediate septal (9.1%) and four out of 22 right-sided pathway procedures (18.2%). These differences were not statistically significant. Average procedure and screening times for all procedures were 162.9 +/- 86.0 min and 56.8 +/- 48.2 min respectively, whereas the median of the number of discharges was 12, ranging from one to 51. There was no significant difference between pathway groups or between concealed and non-concealed pathways in respect to procedure and screening time or number of discharges. There was a significant tendency towards decreased procedure and screening times with accumulating experience and this was similar for all pathway groups. There was also a tendency towards improved cumulative success rates with time dedicated to procedures. We conclude that a certain amount of ablation experience is required, even by experienced electrophysiologists, before a relatively high success rate without long radiation exposure can be achieved, regardless of the location or the mode of conduction of the pathway.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Heart rate variability and its relation to ventricular arrhythmias in congestive heart failure.

BACKGROUND: It has been shown that heart rate variability is decreased in patients with congestive heart failure and that depressed heart rate variability is associated with a propensity to ventricular arrhythmias. Little is known, however, about heart rate variability in patients with both congestive heart failure and ventricular arrhythmias. METHODS: Spectral heart rate variability was analysed from 24 hour ambulatory electrocardiograms in 15 controls, 15 patients with non-sustained ventricular tachycardia associated with clinically normal hearts (NHVT group), and 40 patients with congestive heart failure (CHF group) secondary to either ischaemic heart disease (n = 15) or idiopathic dilated cardiomyopathy (n = 25). Of the 40 patients with congestive heart failure 15 had no appreciable ventricular arrhythmias (ventricular extrasystoles < 10 beats/h and no salvos) and formed the CHF-VA- group. Another 15 patients with congestive heart failure and non-sustained ventricular tachycardia formed the CHF-NSVT group. RESULTS: Heart rate variability was significantly lower in the CHF group than in controls (mean (SD) total frequency 23 (12) v 43 (13) ms; low frequency 12 (8) v 28 (9) ms; high frequency 8 (5) v 14 (7) ms; p < 0.001). The differences in heart rate variability between controls and the NHVT group, between ischaemic heart disease and dilated cardiomyopathy, and between the CHF-VA- and CHF-NSVT groups were not significant. In the CHF group heart rate variability was significantly related to left ventricular ejection fraction but not associated with ventricular arrhythmias. The frequency of ventricular extrasystoles was significantly related to the high frequency component of heart rate variability (r = 0.54, p < 0.05) in the NHVT group. Stepwise multiple regression analysis showed that in the CHF group, heart rate variability was predominantly related to left ventricular ejection fraction (p < 0.05). There was no significant difference in heart rate variability between survivors (n = 34) and those who died suddenly (n = 6) at one year of follow up in the CHF group. CONCLUSION: In patients with congestive heart failure, heart rate variability is significantly decreased. The depressed heart rate variability is principally related to the degree of left ventricular impairment and is independent of aetiology and the presence of ventricular arrhythmias. The data suggest that analysis of heart rate variability does not help the identification of patients with congestive heart failure at increased risk of sudden death.

Adult↗
PubMed1994

Temporal influences on the prediction of postinfarction mortality by heart rate variability: a comparison with the left ventricular ejection fraction.

OBJECTIVE: To examine the influence of the duration of follow up on the values of heart rate variability (HRV) and the left ventricular ejection fraction (LVEF) for predicting mortality after infarction. BACKGROUND: HRV is an index of autonomic balance that identifies patients at a high risk of arrhythmic events. The index is most depressed during the first few weeks after myocardial infarction whereas left ventricular function tends to deteriorate with time. HYPOTHESIS: The value of depressed HRV measured before discharge from hospital for predicting mortality after infarction should decline with time. METHODS: The HRV and the LVEF were assessed in 433 survivors of a first acute myocardial infarction: HRV < 20 units and LVEF < 40% were taken as cut off points. Kaplan-Meier survival functions for total cardiac mortality and sudden cardiac death were calculated for the whole five year follow up period and for different intervening periods. RESULTS: During follow up of four weeks to five years there were 46 (10.6%) deaths and 15 (3.5%) patients died suddenly. Within the whole follow up period, HRV < 20 units and LVEF < 40% were both strongly associated with total cardiac mortality (p < 0.0001), but HRV was an independent predictor of total cardiac mortality only during the first six months of follow up. There were no deaths predicted by HRV < 20 units after the first year of follow up whereas LVEF < 40% had a sensitivity of 43% and a positive predictive accuracy of 9% for predicting death during this period. HRV < 20 units was better than LVEF < 40% in predicting sudden deaths during the first year of follow up but was an independent predictor only of those sudden deaths occurring within six months of infarction. CONCLUSIONS: The duration of follow up affects the prediction of sudden death and total cardiac mortality from HRV. Reduced HRV as measured before discharge from hospital does not seem to retain independent prognostic value after six months of follow up. These findings have potential implications for the serial evaluation of HRV and for the prevention of sudden death after myocardial infarction.

Death, Sudden, Cardiac↗
PubMed1993

Long-term echocardiographic follow-up of acromegalic heart disease.

Heart muscle disease in acromegaly manifests usually as cardiac hypertrophy. Based on a retrospective analysis, it was suggested that cardiac hypertrophy is slowly reversible after normalization of plasma growth hormone levels. The reversibility of acromegalic heart muscle disease during and after treatment of acromegaly was studied prospectively. A cohort of 78 patients was examined echocardiographically in 1981, and 38 survivors of this group were reexamined 10 years later. Patients were classified according to original hormonal activity in 1981, and change in hormonal activity during follow-up into the following 4 groups: group I--hormonally inactive for entire follow-up (n = 10); group II--hormonally active for entire follow-up (n = 11); group III--initially hormonally inactive with later resurgence (n = 6); and group IV--initially hormonally active with later normalization of growth hormone levels (n = 11). No significant echocardiographic changes occurred during follow-up in group I. Left ventricular posterior wall and septal diastolic thickness, and left ventricular mass increased significantly (all p < 0.05) in group II. Left ventricular posterior wall thickness, mass and diastolic volume increased significantly (p < 0.05, < 0.01 and < 0.001, respectively) in group III. On the contrary, there were significant decreases in left ventricular mass, and both diastolic and systolic left ventricular volumes (p < 0.01, < 0.05 and < 0.05, respectively) in group IV. It is concluded that both hypertrophy and dilatation of the left ventricle in acromegaly are slowly reversible after successful treatment. On the contrary, continuing or relapsed hyperproduction of growth hormone causes further deterioration of acromegalic heart disease.

Acromegaly↗
PubMed1993

[Why do we make mistakes in identifying risk patients?].

Risk stratification studies, which are aimed at early identification of patients at high risk of clinical complications, are based on comparatively complex techniques for the analysis of retrospectively collected clinical data. Many of these studies contain serious misconceptions and errors in their analysis. This paper is a methodological review which lists the most frequent errors and omissions in retrospective stratification studies. The paper explains the principle of receiver operator characteristics and positive and negative predictive accuracy, and demonstrates the necessity of using a representative patient population for risk stratification. The danger of misleading conclusions resulting from a multivariate analysis, and several suggestions on how to organise and evaluate these studies are also discussed.

Humans↗
PubMed1993

Influence of thrombolytic therapy on the evolution of baroreflex sensitivity after myocardial infarction.

Depressed baroreceptor sensitivity (BRS) has been associated with an increased risk of ventricular arrhythmias and sudden cardiac death after myocardial infarction, but the influence of thrombolytic therapy on BRS has not been examined. To determine the effect of thrombolytic therapy on the evolution of BRS after myocardial infarction, BRS was assessed at 6 days, 6 weeks, and 3 months in 76 patients, 53 (70%) of whom had received thrombolytic therapy. The mean age (57 vs 57 years), sites of infarction, and the proportion of patients taking beta-blockers (68% vs 52%) did not differ between patients who did and those who did not receive thrombolytic therapy. There was no difference in predischarge mean left ventricular ejection fractions (42% vs 46%) between the two groups of patients, but mean baseline BRS was 9.2 (0.8) msec/mm Hg in patients who were treated with thrombolysis and 5.9 (1.3) msec/mm Hg in those who were not (p = 0.03). At 6 weeks the corresponding values were 9.7 (1.1) and 11.1 (2.8) msec/mm Hg (p = 0.6) and at 3 months 9.1 (1.0) and 6.5 (1.1) msec/mm Hg (p = 0.07). At baseline 13% of patients who were treated with thrombolysis and 13% of those who were not had BRS < 3.0 msec/mm Hg, but at 3 months 9% of patients who were treated with thrombolytic agents compared with 17% of those who had BRS < 3.0 msec/mm Hg. In conclusion, early after myocardial infarction mean BRS was higher in patients treated with thrombolysis compared with nontreated patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗