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PubMed2005

Pediatric patients with multi-organ dysfunction syndrome receiving continuous renal replacement therapy.

BACKGROUND: Critical illness leading to multi-organ dysfunction syndrome (MODS) and associated acute renal failure (ARF) is less common in children compared to adult patients. As a result, many issues plague the pediatric ARF outcome literature, including a relative lack of prospective study, a lack of modality stratification in subject populations and inconsistent controls for patient illness severity in outcome analysis. METHODS: We now report data from the first multicenter study to assess the outcome of pediatric patients with MODS receiving continuous renal replacement therapy (CRRT). One hundred twenty of 157 Registry patients (63 male/57 female) experienced MODS during their course. RESULTS: One hundred sixteen patients had complete data available for analysis. The most common causes leading to CRRT were sepsis (N= 47; 39.2%) and cardiogenic shock (N= 24; 20%). Overall survival was 51.7%. Pediatric Risk of Mortality (PRISM 2) score, central venous pressure (CVP), and% fluid overload (%FO) at CRRT initiation were significantly lower for survivors versus nonsurvivors. Multivariate analysis controlling for severity of illness using PRISM 2 at CRRT initiation revealed that%FO was still significantly lower for survivors versus nonsurvivors (P < 0.05) even for patients receiving both mechanical ventilation and vasoactive pressors. We speculate that increased fluid administration from PICU admission to CRRT initiation is an independent risk factor for mortality in pediatric patients with MODS receiving CRRT. CONCLUSION: We suggest that after initial resuscitative efforts, an increased emphasis should be placed on early initiation of CRRT and inotropic agent use over fluid administration to maintain acceptable blood pressure.

Adolescent↗
PubMed1993

Oral disease and physical disability in community-dwelling older persons.

OBJECTIVE: The aim of this epidemiologic investigation was to determine whether poor oral health in older persons was associated with physical disability. DESIGN: The study was a cross-sectional survey involving in-home interviews and dental examinations of older persons. SETTING: A random sample of 68 cities and towns was selected from the six New England states, with stratification according to population size. PARTICIPANTS: The study sample consisted of 1,156 community-dwelling (non-institutionalized) individuals aged 70 and over, randomly selected from the Medicare beneficiary lists for each city and town. MEASUREMENTS: Oral health was assessed by three dichotomous indices: edentulism (no teeth); current caries, including either coronal or root decay; and periodontal disease, as measured by gingival pocket depth. Physical disability was indicated by the subject's self-report of difficulty in the areas of personal care (eating, bathing, dressing, and using the toilet) and mobility (walking, bed transfer, getting outside). Additional independent variables included age, sex, number of teeth, education, living alone, oral hygiene practices, and time since last dental visit. RESULTS: We found a direct association between specific areas of physical disability and current caries and edentulism. The risk of poor oral health did not increase with advancing age once the related risk factors were controlled for. Those subjects with mobility disabilities were at increased risk of tooth loss; those with personal care limitations were at increased risk of current caries. CONCLUSIONS: Physical disability should be added to the list of known risk factors for oral disease among the older population. Our findings call attention to the need for health care providers to screen for oral health problems among disabled older persons. Further gerontologic research is needed to identify the mechanisms linking physical disability with oral disease in older persons.

Activities of Daily Living↗
PubMed1962

The ABO and rhesus blood groups in Perthes' disease.

Determinations were carried out of the ABO blood groups and Rhesus phenotypes of a series of 142 children with Perthes' disease. Where possible their parents and sibs were also grouped. Sera from the mothers of affected children were examined for the presence of Rhesus antibodies. No apparent association was demonstrated between Perthes' disease and any ABO phenotype. The disease is also apparently independent of ABO incompatibility between mother and child. There is the suggestion in these families of an increased incidence of the Rhesus cc phenotype among the affected children. The level of significance is estimated at 0.02, even after taking into account the numerous significance tests possible on the data. Parental and sibship studies show that any association between Perthes' disease and the Rhesus Cc phenotypes, if one does exist, is unlikely to be the product of genetical stratification within the population. Maternal Rhesus antibody, acting through the agency of haemolytic disease of the newborn, plays no detectable part in the aetiology of a subsequently developing Perthes' disease in the child.

ABO Blood-Group System↗
PubMed2006

Inherited thrombophilia and stratification of ischaemic stroke risk among users of oral contraceptives.

BACKGROUND: Whether use of oral contraceptives is a risk factor for arterial ischaemic stroke is controversial. In particular, few data are available on what criteria should be adopted to establish an individual profile of risk before the start of oral contraceptives. PATIENTS AND METHODS: The effects of oral contraceptives and their interaction with the G1691A polymorphisms of the factor V gene, the G20210A polymorphisms of the prothrombin gene and the C677T polymorphisms of the MTHFR gene on the risk of cerebral ischaemia were determined in a series of 108 consecutive women aged <45 years with ischaemic stroke and 216 controls, in a hospital-based case-control study design. RESULTS: Use of oral contraceptives was associated with an increased risk of cerebral ischaemia (odds ratio (OR) 3.95; 95% confidence interval (CI) 2.29 to 6.78). ORs for stroke were 2.25 (95% CI 1.15 to 4.40), 3.94 (95% CI 2.28 to 6.81) and 8.87 (95% CI 3.72 to 21.1) for non-oral contraceptive users with the TT MTHFR genotype, oral contraceptive users without the TT MTHFR genotype and oral contraceptive users with the TT MTHFR genotype, respectively, when compared with non-oral contraceptive users without the TT MTHFR genotype, with a multiplicative independent effect. Compared with non-oral contraceptive users, ORs for stroke were 2.65 (95% CI 1.46 to 4.81) for oral contraceptive users with none of the studied polymorphisms and 22.8 (95% CI 4.46 to 116.00) for oral contraceptive users with at least one of the studied polymorphisms, with a synergistic effect. CONCLUSIONS: Exposure to the effects of oral contraceptives may increase the risk of ischaemic stroke in women with an inherited prothrombotic background. Testing for these genetic variants may allow more accurate stratification of the population at risk before long-term use of oral contraceptives is prescribed.

Adult↗
PubMed2006

[Ankle-brachial index in patients with diabetes mellitus: prevalence and risk factors].

INTRODUCTION: Diabetic patients have a high cardiovascular morbidity and mortality rate. Ankle brachial index (ABI) is an available, straightforward and reproducible method for the detection of peripheral vascular disease and for improving risk stratification in this population. The objective of our study was to evaluate the prevalence of a low and a pathological ABI in type 2 diabetics older than 60 years and to study the risk factors associated with its development. PATIENTS AND METHODS: 1,360 subjects between 60 and 79 years, 213 of them diabetics, without symptoms of intermittent claudication and who gave their consent to have an ABI measurement in their primary care center were included in the study. Cardiovascular risk factors were evaluated in all participants. An ABI < 0.9 was considered low and a value < 0.9, >or= 1.4 or non-compressible was considered pathological. RESULTS: Prevalence of a low ABI in subjects with or without diabetes was 11.3% and 4.3% and prevalence of a pathological ABI was 18.8% and 7%, respectively. Factor associated with a low or pathological ABI were gender, age, duration of diabetes, the type of antidiabetic treatment and the presence of vascular disease in another vascular bed. After multivariate adjustment, only age (OR: 1.15; 95% CI: 1.04-1.27) and duration of diabetes (OR: 1.05; 95% CI: 1.01-1.10) continue being significant. The prevalence of a pathological ABI did not differ between diabetics without vascular disease and non-diabetics with previous cardiovascular disease. CONCLUSION: The prevalence of a low or pathological ABI is elevated in diabetic subjects and relates with age, duration of diabetes and the presence of vascular disease in another vascular bed.

Aged↗
PubMed2006

[Primary prophylaxis with the implantable cardioverter-defibrillator in heart failure: a clinical point of view].

The implantable cardioverter-defibrillator (ICD) is one of the great inventions of modern cardiology. Its use for the prevention of sudden death in patients with left ventricular dysfunction has meant that clinical cardiologists are now fully involved in decision-making on the implantation of these devices. The majority of clinical trials, which have used low ejection fraction as the only or main criterion for patient recruitment, have shown that ICD use leads to a significant improvement in survival. Three trials, two of which were carried out soon after myocardial infarction and one of which was performed at the same time as surgical revascularization, were exceptions. However, it is important to be aware that the improvements observed in the most recent trials have not been as large as those seen in the initial studies. Reduced efficacy has meant that in the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT), for instance, 25 ICDs had to be implanted to save one life over a 2-year period. The most likely explanation for this observation is that the better prognosis achieved by present-day pharmacologic treatment of heart failure has reduced the margin of benefit associated with ICD use. Another consequence is that depressed left ventricular ejection fraction has lost some of its specificity in predicting sudden death. New predictive variables are needed to improve risk stratification in this population. Without these variables, the use of ICDs in the primary prevention of sudden death in patients with left ventricular dysfunction will not seem a very attractive option from the point of view of good clinical practice.

Arrhythmias, Cardiac↗
PubMed2003

A new powerful non-parametric two-stage approach for testing multiple phenotypes in family-based association studies.

We introduce a new powerful nonparametric testing strategy for family-based association studies in which multiple quantitative traits are recorded and the phenotype with the strongest genetic component is not known prior to the analysis. In the first stage, using a population-based test based on the generalized estimating equation approach, we test all recorded phenotypes for association with the marker locus without biasing the nominal significance level of the later family-based analysis. In the second stage the phenotype with the smallest p value is selected and tested by a family-based association test for association with the marker locus. This strategy is robust against population admixture and stratification and does not require any adjustment for multiple testing. We demonstrate the advantages of this testing strategy over standard methodology in a simulation study. The practical importance of our testing strategy is illustrated by applications to the Childhood Asthma Management Program asthma data sets.

Asthma↗
PubMed1993

Prediction of repetition of parasuicide: with special reference to unemployment.

Economically active male parasuicides admitted to the Regional Poisoning Treatment Centre, Edinburgh in 1984 were divided into two groups--those with a previous history of parasuicide and those without. The two groups were compared on a number of psychosocial and clinical characteristics to examine which were related to repetition. A further analysis (of economically active male admissions in 1985 and 1986) tested the predictive value of these discriminating characteristics. By stratification of the population, the interaction of unemployment (a discriminator and a predictor of repetition) with certain other variables was examined. A final analysis examined the risk of repetition by duration of unemployment. Unemployment discriminated those with a past history of repetition from those with no past history and also predicted repetition within a calendar year of the initial episode. The 35-64 age group were particularly vulnerable to repetition if unemployed as were those in social classes I-III and those with a past psychiatric history (inpatient or outpatient). The relationship between unemployment and parasuicide was no longer significant when the population was stratified by presence or absence of personality disorder and history of previous parasuicide, suggesting that these might be confounding variables in the relationship. The particular vulnerability of the long-term unemployed (greater than one year) to repetition was confirmed.

Adolescent↗
PubMed1993

Effect of angiotensin-converting enzyme inhibitors on ventricular remodeling and survival following myocardial infarction.

OBJECTIVE: To discuss the effects of angiotensin-converting enzyme (ACE) inhibitors on ventricular remodeling and survival after acute myocardial infarction (AMI). An overview is provided of the pathophysiologic changes produced by AMI and the ventricular remodeling process. ACE inhibitors have been studied for their use in the prevention of ventricular remodeling and reduction in postinfarction mortality. Trials in humans and animals are reviewed, including study methods, results, and limitations. DATA SOURCES: MEDLINE searches identified applicable literature, including experimental trials and review articles. STUDY SELECTION: All clinical trials of ACE inhibitors following AMI were reviewed. DATA EXTRACTION: Morbidity and mortality data evaluating the effect of postinfarction ventricular remodeling are rare. At the time of publication, all available clinical trials studying the effects of ACE inhibitors on postinfarction ventricular remodeling were included, regardless of whether morbidity and mortality were assessed. Data from the Survival and Ventricular Enlargement (SAVE) and Cooperative New Scandinavian Enalapril Survival Study II (CONSENSUS II) trials include almost 10,000 patients. Data were extracted by two independent observers. Data quality and validity were assessed based on sample size, stratification of study population, and statistical power of the studies. DATA SYNTHESIS: ACE inhibitors may prevent the deleterious consequences of AMI, including ventricular remodeling and neurohumoral activation. Ventricular hypertrophy begins acutely following infarction, an early physiologic response to myocardial injury. Hemodynamic benefits from the initial phase of left ventricular hypertrophy include increased ventricular working capacity, normalized systolic wall stress, and maintenance of stroke volume. Although acute dilatation may delay hemodynamic deterioration for six to eight months, it also results in reduced coronary reserve, decreased ventricular compliance, and altered myocardial contractility. With chronic dilatation, the beneficial effects reach a plateau, stroke volume decreases, contractility is reduced, and cardiac failure may ensue. Ventricular hypertrophy is associated with worsened prognosis following infarction and may be the most important single determinant of late prognosis. Ventricular hypertrophy contributes to postinfarction heart failure, angina, and sudden death. Clinical trials show a beneficial effect of the ACE inhibitor captopril on the prevention of left ventricular dysfunction. Although captopril therapy significantly improved survival and myocardial function following AMI in the SAVE trial, these results cannot be generalized to all patient subpopulations. The CONSENSUS II trial demonstrated a decreased survival rate when enalapril was administered within 24 hours of AMI, indicating that timing of therapy may be an important consideration. Captopril therapy may positively affect outcome when initiated 3-16 days following infarction in patients with ejection fractions below 40 percent and who have no signs of ischemia or heart failure. Based on the CONSENSUS II results, enalapril therapy immediately following AMI cannot be recommended. CONCLUSIONS: Clinical trials have demonstrated that ACE inhibitors can limit ventricular hypertrophy following AMI, resulting in clinical benefit and improved survival. These effects may be secondary to modulation of neurohumoral activation or the antiischemic effect of ACE inhibitors, which may also reduce the incidence of reinfarction. Early intervention with ACE inhibitors (within 3-16 days of infarction) can slow the progression of cardiovascular disease and improve the survival rate.

Angiotensin-Converting Enzyme Inhibitors↗
PubMed2005

Sibship T2 association tests of complex diseases for tightly linked markers.

For population case-control association studies, the false-positive rates can be high due to inappropriate controls, which can occur if there is population admixture or stratification. Moreover, it is not always clear how to choose appropriate controls. Alternatively, the parents or normal sibs can be used as controls of affected sibs. For late-onset complex diseases, parental data are not usually available. One way to study late-onset disorders is to perform sib-pair or sibship analyses. This paper proposes sibship-based Hotelling's T2 test statistics for high-resolution linkage disequilibrium mapping of complex diseases. For a sample of sibships, suppose that each sibship consists of at least one affected sib and at least one normal sib. Assume that genotype data of multiple tightly linked markers/haplotypes are available for each individual in the sample. Paired Hotelling's T2 test statistics are proposed for high-resolution association studies using normal sibs as controls for affected sibs, based on two coding methods: 'haplotype/allele coding' and 'genotype coding'. The paired Hotelling's T2 tests take into account not only the correlation among the markers, but also take the correlation within each sib-pair. The validity of the proposed method is justified by rigorous mathematical and statistical proofs under the large sample theory. The non-centrality parameter approximations of the test statistics are calculated for power and sample size calculations. By carrying out power and simulation studies, it was found that the non-centrality parameter approximations of the test statistics were accurate. By power and type I error analysis, the test statistics based on the 'haplotype/allele coding' method were found to be advantageous in comparison to the test statistics based on the 'genotype coding' method. The test statistics based on multiple markers can have higher power than those based on a single marker. The test statistics can be applied not only for bi-allelic markers, but also for multi-allelic markers. In addition, the test statistics can be applied to analyse the genetic data of multiple markers which contain double heterozygotes--that is, unknown linkage phase data. An SAS macro, Hotel_sibs.sas, is written to implement the method for data analysis.

Diabetes Mellitus↗
PubMed1983

Doxorubicin, mitomycin-C, and 5-fluorouracil (DMF) in the treatment of metastatic hormonal refractory adenocarcinoma of the prostate, with a note on the staging of metastatic prostate cancer.

Sixty-two patients with metastatic hormonal refractory adenocarcinoma of the prostate received a combination of doxorubicin, mitomycin-C, and 5-fluorouracil (DMF). Thirty (48%) of the patients achieved an objective response. Response criteria excluded disease "stabilization" as a manifestation of response. Four clinical prognostic categories were identified: osseous I (OI) had metastatic axial skeletal involvement (23 patients); osseous II (OII) had axial and extremity skeletaL involvement (18 patients); visceral I (VI) had pulmonary metastasis (9 patients); and visceral II (VII) had pulmonary metastasis and involvement of other viscera (12 patients). The 20 responding patients survived a median of 47.5 weeks, whereas the 32 nonresponding patients survived a median of 23.8 weeks (n = 0.002). Response rates were highest among patients with OI (52%) and VI (88%) disease; response rates were lower amont patients with OII (33%) and VII (33%) disease. Responding patients in each clinical category survived longer than nonresponding patients except for those patients with VII disease. The median duration of response for patients with OI disease was 11 months, for OII 9.5 months, for VI patients it was 6.5 months, and VII patients it was 5 months. DMF is an effective treatment of metastatic hormonal refractory prostate cancer, resulting in consistent objective responses. The staging system employed identifies four clinical categories of metastatic prostate cancer and allows for accurate comparison of diet and stratification of study populations.

Adenocarcinoma↗
PubMed1998

Guide to epidemiological surveillance for rinderpest. Office International des Epizooties.

The practical implementation of epidemiological surveillance programmes for rinderpest prescribed by the standards of the Office International des Epizooties (OIE) is described. The rationale of surveillance is discussed in relation to the stages of disease control, discontinuation of vaccination, clinical surveillance and serological surveillance. These stages lead to provisional and confirmed declarations of freedom from disease, and the confirmed declaration of freedom from infection. Practical methods of stratification of livestock populations, and selection of samples of herds and animals within selected herds are explained. The actions to follow any discovery of disease, or any clinical or serological signs of disease, are discussed. In the serological surveillance stage, balancing the number of herds and the number of animals within selected herds tested can result in considerable reduction in the overall number of serum samples to be tested. The methods used in rinderpest surveillance can readily be adapted to surveillance programmes for other diseases.

Animals↗
PubMed2025

The X-Linked TLR7 rs179008 T Allele Is Associated with an Increased Risk of Severe Multisystem Inflammatory Syndrome in Children/Kawasaki-like Syndrome in SARS-CoV-2-Infected Boys.

The X-linked TLR7 rs179008 T allele has been associated with altered antiviral immunity. Given their shared inflammatory pathways and higher pediatric mortality rates in Brazil during the pandemic, we investigated their association with multisystem inflammatory syndrome in children (MIS-C) together with Kawasaki disease (KS) following SARS-CoV-2 infection. A cross-sectional study (2021-2022) analyzed 73 hospitalized children (<13 years) with confirmed COVID-19. Genotyping for TLR7 rs179008, TLR8 (rs3764879, rs2407992), and TLR3 rs3775291 was performed via PCR and Sanger sequencing. MIS-C/KS cases were identified using CDC criteria, with severity classified by the need for ICU care. Statistical analysis included Fisher's exact test and relative risk (RR) calculations. Hemizygous boys carrying the TLR7 T allele had a 1.87-fold higher risk of MIS-C/KS (p = 0.007) and a 1.75-fold increased risk of severe or critical outcomes. The T allele frequency was 2.6&#xd7; higher in MIS-C/KS cases versus other COVID-19 presentations. All fatalities occurred in boys (3/8 MIS-C cases) with one T-allele carrier. No associations were found for TLR8 or TLR3 variants. The TLR7 rs179008 T allele is a potential genetic risk factor for severe post-COVID-19 inflammatory syndromes in boys, likely due to impaired immune signaling. These findings highlight its utility as a biomarker for risk stratification in pediatric populations.

Humans↗
PubMed2001

Less medical intervention after sharp demarcation of Grade 1-2 cervical intraepithelial neoplasia smears by neural network screening.

BACKGROUND: Neural network technology has been used for the daily screening of cervical smears in The Netherlands since 1992. The authors believe this method might have the potential to demarcate diagnoses of Grade 1-2 cervical intraepithelial neoplasia (CIN 1-2). METHODS: Of 133,196 women who were screened between 1992-1995, there were 2236 CIN 1-2 smears; 1128 of which were detected by means of neural network screening (NNS) (n = 83,404 women) and 1108 of which were diagnosed by conventional screening (n = 49,792 women). Cytologic and clinical outcomes (first cytologic or histologic follow-up diagnosis) were retrieved for all the women in the study population (n = 1920). Stratification based on clinical outcome resulted in the cases being grouped as overdiagnosed, concordant, or underdiagnosed. The smears were performed by general practitioners, whereas the biopsies were obtained by gynecologists. RESULTS: The prevalence rate for CIN 1-2 was 1.15% (95% confidence interval [95% CI], 1.08-1.23%) for NNS and 1.92% (95% CI, 1.80-2.04%) for conventional diagnosis (P < 0.001). Concordance with histology was significantly higher for NNS (53.9%; 95% CI, 50.7-57.0%) compared with conventional screening (29.2%; 95% CI, 26.4-32.2%). In addition, overdiagnosis was significantly lower for cases diagnosed by NNS (39.4%; 95% CI, 36.3-42.4%) compared with cases diagnosed by conventional screening (62.4%; 95% CI, 59.3-65.5%). CONCLUSIONS: Neural network-based screening can lead to fewer women being burdened unnecessarily with a cytologic diagnosis of CIN 1-2 by resulting in a sharp demarcation in these diagnoses and a corresponding reduction in unnecessary medical interventions. [See editorial on pages 171-172, this issue.]

Cytogenetic Analysis↗
PubMed2001

Unbiased discordant sib-pair tests when parental genotypes are missing.

Population admixture and stratification are potential sources of confounding in a variety of statistical analyses of genetic data. Many approaches to adjusting for such confounding have been developed in the context of association analyses. These approaches may generally be viewed as relying on nonparametric null hypotheses that specify certain, sometimes incompletely observed, conditional distributions; the conditional distributions are used to normalize test statistics to have expectation zero under the null hypothesis. Here, with a very simple example, it is shown that there is potentially information that is free of confounding, but that is not recovered by such normalized statistics. An approach presented here in the context of the simple example might be extended to methods for recovering information in more complex settings.

Bias↗
PubMed1985

Relationship between insulin response to intravenous glucose and plasma lipoproteins in healthy men.

In order to evaluate the influence of serum insulin levels on serum lipoprotein composition, 62 randomly selected healthy males were studied. All of them had a normal glucose tolerance. The Insulin Response to a bolus of intravenous glucose (0.50 g/kg) was significantly correlated with VLDL-Triglyceride (p less than 0.01), VLDL-Cholesterol (p less than 0.01) and with the "Atherogenic Index" (Formula: see text) (p less than 0.01). Moreover, stratifing the all population in quartiles according to the Insulin Response distribution, the highest quartile had a significant increase in Total and VLDL-Cholesterol levels (p less than 0.02), as well as in Total (p less than 0.02), VLDL (p less than 0.02) and LDL (p less than 0.01) Triglyceride, in comparison with the lowest quartile. The Atherogenic Index was also significantly elevated in the high Insulin Response group (p less than 0.005). The influence of serum insulin on lipoprotein metabolism was also evaluated by a stepwise multiple regression analysis. Body weight, Insulin Response and Exogenous Triglyceride removal were independently correlated with VLDL-Triglyceride concentration (r = 0.58, p less than 0.001). VLDL cholesterol concentration and fasting serum insulin levels were inversely correlated with HDL-Cholesterol (r = 0.49, p less than 0.001). In conclusion, in absence of any metabolic derangement, high insulin levels are associated with multiple lipoprotein abnormalities. Insulin might act as a risk factor for arterial disease through its influence on serum lipoproteins.

Adult↗
PubMed1984

Factors influencing postoperative survival in aortic regurgitation. Analysis by Cox regression model.

From 1965 to 1981, 114 patients underwent aortic valve replacement for severe aortic regurgitation in our institution. Catheterization was performed preoperatively in 103 patients. Follow-up was possible in 98% of the survivors. Long-term survival was significantly different between patients in preoperative Functional Class I-II and those in Class III-IV (p less than 0.03); those with a preoperative cardiothoracic ratio less than 0.64 versus greater than or equal to 0.64 (p less than 0.001); and those with a preoperative ejection fraction greater than 0.50 versus less than or equal to 0.50 (p less than 0.03). A multifactorial analysis was used to identify the dominant preoperative prognostic variables affecting survival. Three of the 13 parameters examined simultaneously were found to independently influence survival rates: cardiothoracic ratio (p = 0.001), strain pattern on the electrocardiogram (p = 0.072), and left ventricular end-systolic pressure (p = 0.127). After stratification of the population into two groups according to preoperative functional class, the predictive variables were cardiothoracic ratio (p = 0.014), strain pattern (p = 0.050), and acute/chronic form of aortic regurgitation (p = 0.034). This statistical analysis enabled us to derive a mathematical equation for predicting an individual patient's probability of survival. We found a close fit between the survival rate predicted by the mathematical model and the observed survival rate.

Adolescent↗
PubMed1996

Evaluation of the patient with 'rule out myocardial infarction'.

Evaluation in the emergency department of the patient with chest pain remains a common problem. Large numbers of patients are admitted to the hospital because of diagnostic uncertainty. Strategies dealing with this population include risk stratification by clinical presentation, serial cardiac enzyme assays to exclude myocardial infarction, and detection of myocardial ischemia with nuclear scintigraphy or echocardiography. Each of these strategies is rational with specific benefits and weaknesses. Bypassing these steps and performing immediate exercise testing is the newest approach that appears to be safe, timely, and cost-effective.

Diagnosis, Differential↗