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At least 523 records · Page 29Linked to original sources
PubMed2005

New risk score for patients with acute chest pain, non-ST-segment deviation, and normal troponin concentrations: a comparison with the TIMI risk score.

OBJECTIVES: The purpose of this research was to develop a risk score for patients with chest pain, non-ST-segment deviation electrocardiogram (ECG), and normal troponin levels. BACKGROUND: Prognosis assessment in this population remains a challenge. METHODS: A total of 646 consecutive patients were evaluated by clinical history (risk factors and chest pain score according to pain characteristics), ECG, and early exercise testing. ST-segment deviation and troponin elevation were exclusion criteria. The primary end point was mortality or myocardial infarction at one year. The secondary end point was mortality, myocardial infarction, or urgent revascularization at 14 days (similar to the Thrombolysis In Myocardial Infarction [TIMI] risk score). RESULTS: Primary and secondary end point rates were 6.7% and 5.4%. A risk score was constructed using the variables related to the primary end point: chest pain score > or =10 points (hazard ratio [HR] = 2.5; 1 point), > or =2 pain episodes in last 24 h (HR = 2.2; 1 point), age > or =67 years (HR = 2.3; 1 point), insulin-dependent diabetes mellitus (HR = 4.2; 2 points), and prior percutaneous transluminal coronary angioplasty (HR = 2.2; 1 point). Patients were classified into five categories of risk (p = 0.0001): 0 points, 0% event rate; 1 point, 3.1%; 2 points, 5.4%; 3 points, 17.6%; > or =4 points, 29.6%. The accuracy of the score was greater than that of the TIMI risk score for the primary (C index of 0.78 vs. 0.66, p = 0.0002) and secondary (C index of 0.70 vs. 0.66, p = 0.1) end points. CONCLUSIONS: Patients presenting with chest pain despite no ST-segment deviation or troponin elevation show a non-negligible rate of events at one year. A risk score derived from this specific population allows more accurate stratification than when using the TIMI risk score.

Aged↗
PubMed2006

T-wave alternans and the susceptibility to ventricular arrhythmias.

T-wave alternans (TWA) reflects beat-to-beat fluctuations in the electrocardiographic T-wave, and is associated with dispersion of repolarization and the mechanisms for sudden cardiac arrest (SCA). This review examines the bench-to-bedside literature that, over decades, has linked alternans of repolarization in cellular, whole-heart, and human studies with spatial dispersion of repolarization, alternans of cellular action potential, and fluctuations in ionic currents that may lead to ventricular arrhythmias. Collectively, these studies provide a foundation for the clinical use of TWA to reflect susceptibility to ventricular arrhythmias in several disease states. This review then provides a contemporary evidence-based framework for the use of TWA to enhance risk stratification for SCA, identifying populations for whom TWA is best established, those for whom further studies are required, and areas for additional investigation.

Action Potentials↗
PubMed2006

Toll-like receptor 2 and Toll-like receptor 4 polymorphisms in invasive pneumococcal disease.

BACKGROUND: Toll-like receptors (TLRs) recognize distinct pathogen-associated molecular patterns and trigger anti-microbial host defense responses. Several in vitro and in vivo studies in mice indicate that TLR2 and TLR4 are involved in the defense against Streptococcus pneumoniae. Studies have revealed associations between polymorphisms in TLRs and human diseases. The effect of polymorphisms in TLR2 and TLR4 in the human defense to S. pneumoniae has not been studied. METHODS: We genotyped 99 Caucasian patients with invasive pneumococcal disease and 178 Caucasian controls for the known R579H, P631H and R753Q polymorphisms in TLR2 and the D299G polymorphism in TLR4 with PCR-RFLP methods. RESULTS: The distribution of the TLR2 R579H, P631H and R753Q and TLR4 D299G variants was not significantly different between the patients and the controls. After stratification of the patient population by age, sex, diagnosis, and mortality no significant differences for the TLR2 R753Q genotype and TLR4 D299G genotype were found between various patient subgroups and between patient subgroups and the control population. It should be mentioned that for the TLR2 polymorphisms neither the control group nor the patient group contains homozygous mutant individuals. CONCLUSION: We found no association between TLR2 and TLR4 polymorphisms and invasive pneumococcal infection.

Adolescent↗
PubMed2003

Limited predictive value of inducible sustained ventricular tachycardia for future occurrence of spontaneous ventricular tachycardia in patients with coronary artery disease and relatively preserved cardiac function.

To evaluate the significance of inducible sustained ventricular tachycardia (VT) in patients with coronary artery disease and relatively preserved cardiac function, 33 patients who met the following criteria were studied; documented nonsustained VT but no history of life-threatening arrhythmia, inducible sustained VT at electrophysiologic study, and implantation of a cardioverter-defibrillator. Eighteen patients developed clinical sustained VT within 2 years. By univariate analysis, left ventricular ejection fraction (EF) and the cycle length of induced VT were associated with clinical VT occurrence. By multivariate analysis, however, EF was the only independent predictor. Among 23 patients with EF 40% (P <.01). In coronary artery disease patients with relatively preserved EF, the incidence of clinical VT is considerably low even though sustained VT is inducible. Inducible VT is therefore not appropriate for risk stratification in this patient population.

Aged↗
PubMed2006

A systematic review of longitudinal outcome studies of first-episode psychosis.

BACKGROUND: Existing outcome literature has had an over-representation of chronic patients and suggested a progressive course and poor outcome for schizophrenia. The current study aimed to recombine data of samples from longitudinal studies of first-episode psychosis (FEP) to describe outcome and its predictors. METHOD: A literature search (1966-2003) was conducted for prospective studies examining outcome in first-episode non-affective psychosis using the following key words: early, first, incident, episode, admission, contact, psychosis, schizophrenia, psychotic disorders, course, outcome, follow-up, longitudinal, cohort. These were pooled and analyzed using descriptive and regression analyses. RESULTS: Thirty-seven studies met the inclusion criteria, representing 4100 patients with a mean follow-up of 35.1+/-6.0 months. Studies varied in the categories of outcome used, the most common being 'good' (54% of studies) and 'poor' (34% of studies), variably defined. In studies reporting these categories, good outcomes were reported in 42.2% (3.5%) and poor outcomes in 27.1% (2.8%) of cases. Predictors associated with better outcome domains were: combination of pharmacotherapy and psychosocial therapy, lack of epidemiologic representativeness of the sample, and a developing country of origin. Use of typical neuroleptics was associated with worse outcome. Stratification analyses suggested that populations with schizophrenia only, and those with prospective design, were associated with worse outcome domains. CONCLUSIONS: Outcome from FEP may be more favorable than previously reported, and treatment and methodological variables may be important contributors to outcome. Significant heterogeneity in definitions and methodology limited the comparison and pooling of data. A multi-dimensional, globally used definition of outcome is required for future research.

Cohort Studies↗
PubMed2002

Safety of dobutamine stress echocardiography in patients with unruptured intracranial aneurysms.

Dobutamine stress echocardiography has been increasingly used for the preoperative assessment of patients who undergo major vascular surgery. The safety of this modality has been well documented in various patient subgroups, including patients with aneurysms of the aorta. No previous reports, however, have addressed the safety of this form of stress testing in patients with unruptured intracranial aneurysms. After reviewing the experience of 2 institutions, we identified 40 patients who underwent dobutamine stress echocardiography while harboring at least 1 unruptured intracranial aneurysm, and found no evidence of aneurysm instability in relation to the dobutamine infusion. Although vasodilator stress modalities should intuitively be the non-exercise stress technique of choice in these patients, stress echocardiography with the use of dobutamine appears to be safe and represents an acceptable option when used for diagnostic purposes or preoperative risk stratification in this patient population.

Aged↗
PubMed2001

A functional polymorphism of toll-like receptor 4 is not associated with likelihood or severity of meningococcal disease.

Human Toll-like receptor 4 (TLR4) transduces proinflammatory cytokine release by human cells in response to lipopolysaccharide (LPS). This study tested the hypothesis that, if TLR4 is rate limiting for a successful response to bacterial LPS in humans, a human gene polymorphism that results in the amino acid substitution Asp299Gly and causes reduced expression and function of TLR4 should influence susceptibility to or severity of natural gram-negative infection. The allele frequency of the Asp299Gly polymorphism was 5.9% among 879 blood donors, 6.5% among 1047 patients with microbiologically proven meningococcal disease, and 4.1% among 86 patients who died of meningococcal disease. No significant differences were observed, including those analyzed after stratification of the infected population by age and by meningococcal serogroup. Therefore, this functional TLR4 polymorphism does not influence susceptibility to or severity of meningococcal disease.

Adolescent↗
PubMed2004

Testicular cancer.

PURPOSE OF REVIEW: The purpose of this article is to review the recent clinically relevant literature on testicular cancer. RECENT FINDINGS: Recent studies suggest that an increased incidence of testicular cancer is due to a birth-cohort effect and secondary to early exposure. Work on identifying tumor prognostic characteristics suggests that proliferation and apoptosis markers as well as serum lactate dehydrogenase isoenzyme 1 (S-LD-1) may have value. Poor-risk patients may benefit from intensive treatment despite a possible increased risk of significant toxicity and treatment related deaths. Studies continue to show the efficacy of radiation for stage I and stage II seminoma, but another study adds to the evidence that adjuvant carboplatin may be an acceptable alternative in stage I disease. Surgical studies suggest that even patients with minimal findings on computed tomography after chemotherapy are at risk for harboring vital tumor. Surveillance is shown to be an acceptable choice for highly compliant patients with early stage disease. Risk factors predictive of bleomycin pulmonary toxicity are proposed. Fertility remains an area of concern. SUMMARY: Testicular cancer research continues to modify current therapies, increase the understanding of the molecular basis of the disease, and improve the risk stratification of the patient population so as to minimize exposure to treatment-related morbidity and toxicity.

Fertility↗
PubMed2005

Risk prediction in patients with chest pain: early assessment by the combination of troponin I results and electrocardiographic findings.

OBJECTIVE: To evaluate the prognostic value of point of care troponin I (TnI) results in combination with findings from the admission electrocardiogram (ECG) in patients with chest pain. METHODS: Rapid measurements of TnI were performed in 191 consecutive patients with chest pain and a non-diagnostic ECG for myocardial infarction. RESULTS: Within 6 h from admission, maximum TnI elevations of > or = 0.07 microg/l and > or = 0.1 microg/l were noted in 59 and 39% of all patients, respectively. TnI elevations in the range of 0.07-0.09 microg/l were found in many patients with diagnoses other than acute coronary syndrome. By 6-month follow-up, cardiac death had occurred in 7.1 and 11% of patients with maximum TnI > or = 0.07 microg/l and > or = 0.1 microg/l, respectively and myocardial reinfarction was documented in 12 and 15%, respectively. ST-segment depression on the admission ECG was present in 16% of all patients and was the electrocardiographic abnormality with the highest risk (cardiac death 7.7%, myocardial reinfarction 15%). The combination of TnI > or = 0.1 microg/l and ST-segment depression or an abnormal admission ECG in general allowed the identification of patients at low, intermediate and high cardiac risk, 3 h after admission. CONCLUSION: A threshold of TnI > or = 0.1 microg/l corresponding to the 10% coefficient of variation is prognostically most suitable for prediction of cardiac events in patients with chest pain. The combination of TnI results and findings from the admission ECG improves prognostic assessment and allows early and reliable risk stratification in this patient population.

Aged↗
PubMed2003

Central line thrombosis in patients with cancer.

Central venous catheters are used frequently to care for patients with cancer and often serve as long-term venous access. Catheter-related central venous thrombosis is a serious and common complication in these patients. The incidence of this event ranges from 2 to 40%. Potential risk factors are catheter position, size of the catheter, and perhaps site of insertion. The diagnosis of catheter-associated deep venous thrombosis may be difficult. Doppler ultrasound has a lower accuracy in this setting than it does in symptomatic lower extremity venous thrombosis. No clinical management studies have validated the practice of withholding anticoagulant therapy in patients with a negative Doppler ultrasound. The practice of prophylaxis with low-dose warfarin or low-molecular-weight heparin has been recommended, although results from recent studies have called this into question. Larger, prospective, randomized trials with a uniform population of patients or stratification of risk factors will be essential to address this issue further.

Anticoagulants↗
PubMed2005

Impact of age and basic heart rate on heart rate turbulence in healthy persons.

Postextrasystolic acceleration of heart rate (HR), known as HR turbulence (HRT) is attenuated in patients with coronary artery disease at increased risk of adverse events. The influence of age and basic HR on HRT have not been evaluated in a large cohort of persons. In 95 healthy individuals, HRT onset (TO) and slope (TS) were calculated from 24-hour ambulatory electrocardiograms, as well as the turbulence timing (TT). Gender specific differences in TO and TS were compared in simple, linear, weighted regression model. The influence of age and the basic HR preceding ventricular premature contractions on HRT were examined. We found that, in men and women, TO decreases as basic HR increases (P < 0.01). In contrast, in men, TS decreased as basic HR increases, whereas in women, basic HR influenced TS only slightly (P < 0.01). A multiple, linear regression model revealed a decrease in HRT with increasing age in men. In conclusion, physiological acceleration of the HR within the first 11 beats after premature ventricular complex (VPC) was observed in >75% of healthy individuals. An accelerating HR preceding the VPC influenced HRT in men. An increasing age was associated with a decrease in HRT in men and a decrease in TO in women. These results illustrate the importance of physiological modulations of HRT when used for risk stratification, especially in older populations.

Adult↗
PubMed2006

[Cardiovascular risk by Framingham and SCORE in patients 40-65 years old].

BACKGROUND AND OBJECTIVE: The aim of this study was to compare the clinical and treatment implications of 2 cardiovascular risk stratification systems in a population of patients 40-65 years old. PATIENTS AND METHOD: 929 non diabetic patients (40-65 years old) (51% female) with no evidence of previous cardiovascular disease were included in the study. The risk of cardiovascular death was assessed with the charts of the Systematic Coronary Risk Evaluation (SCORE), and coronary risk by the Framingham function (National Cholesterol Education Program Expert Panel on Detection, Evaluation and Treatment of High Blood Cholesterol in Adults -NCEP-ATP-III-). Patients were considered of high risk if risk of cardiovascular death was >or= 5% and coronary risk was > 20%, respectively. RESULTS: 4.1% of patients were considered as high risk by SCORE and 2.5% by Framingham. Only 0.2% of females were classified as high risk with either system. 8.2% and 4.8% of male population were considered as high risk by SCORE and Framingham, respectively. There was a low level of concordance between both systems. Patients classified as high risk by SCORE but not by Framingham were older, smoke less and had a better lipid profile. According to European Guidelines 28% of male and 23% of female were candidates to hypolipemic treatment, that proportion was higher, 43% of males and 28% of females, by NCEP-ATP-III guidelines. CONCLUSIONS: In Spanish patients 40-65 years old, SCORE charts almost duplicate the number of high risk individuals compared to Framingham. although the number of patients candidates to hypolipemic treatment is lower with the European than ATP-III guidelines. Differences were more evident in male.

Adult↗
PubMed2001

Genetic heterogeneity in five Italian regions: analysis of PAH mutations and minihaplotypes.

Molecular analysis of 289 chromosomes has been performed in a cohort of phenylketonuria (PKU) patients whose ancestors lived in five Italian regions, Calabria, Campania, Piemonte, Puglia/Basilicata and Sicilia. Phenylalaninehydroxylase (PAH) gene mutations and minihaplotypes (combinations of PAH gene STR and VNTR systems) have been determined for 78.5 and 64%, respectively, of the chromosomes studied. 21 different minihaplotypes and 24 PKU mutations were found. Heterogeneity tests carried out for the frequencies of mutations and minihaplotypes show that the distribution of eight mutations and four minihaplotypes is statistically heterogeneous in the five Italian regions. Although the evolutionary rate of microsatellites or the age of these mutations is difficult to estimate with accuracy, our findings taken together show a genetic stratification of the Italian population. These results rule out allelic homogeneity of PKU at the molecular level between regions of Italy, yet minihaplotype data may be of practical use for a multistep approach to PAH gene genotyping.

Alleles↗
PubMed1999

Prediction of sustained ventricular tachycardia inducible by programmed stimulation in patients with coronary artery disease. Utility of clinical variables.

BACKGROUND: Cardiologists often use clinical variables to determine the need for electrophysiological studies to stratify patients for risk of sudden death. It is not clear whether this is rational in patients with coronary artery disease, left ventricular dysfunction, and nonsustained ventricular tachycardia. METHODS AND RESULTS: We analyzed the first 1721 patients enrolled in the Multicenter UnSustained Tachycardia Trial to determine whether clinical variables could predict which patients would have inducible sustained monomorphic ventricular tachycardia. The rate of inducibility of sustained ventricular tachycardia was significantly higher in patients with a history of myocardial infarction and in men compared with women. There was a progressively increased rate of inducibility with increasing numbers of diseased coronary arteries. There was a significantly lower rate of inducibility in patients with prior coronary artery bypass surgery and in patients who also had noncoronary cardiac disease. The rate of inducibility was higher in patients of white race, patients with recent (</=6 weeks) angina, left ventricular dyskinesis, and in patients with greater numbers of fixed thallium defects. Inducibility was more likely in patients who had a prior myocardial infarction complicated by congestive heart failure, ventricular tachycardia, or fibrillation </=48 hours after the onset of infarction. Although these associations are statistically significant, the accuracy of the clinical variables in discriminating between patients with and those without inducible ventricular tachycardia is only modest (receiver operator characteristic area <0.70). CONCLUSIONS: Multiple clinical variables are independently associated with inducible sustained ventricular tachycardia. However, they have limited utility to guide clinical decisions regarding the use of electrophysiological testing for risk stratification in this patient population.

Aged↗
PubMed2006

Causal analysis of case-control data.

In a series of papers, Robins and colleagues describe inverse probability of treatment weighted (IPTW) estimation in marginal structural models (MSMs), a method of causal analysis of longitudinal data based on counterfactual principles. This family of statistical techniques is similar in concept to weighting of survey data, except that the weights are estimated using study data rather than defined so as to reflect sampling design and post-stratification to an external population. Several decades ago Miettinen described an elementary method of causal analysis of case-control data based on indirect standardization. In this paper we extend the Miettinen approach using ideas closely related to IPTW estimation in MSMs. The technique is illustrated using data from a case-control study of oral contraceptives and myocardial infarction.

Journal Article↗
PubMed2006

Mycophenylate mofetil: what role in the treatment of lupus?

Improved patient survival following lupus nephritis with the institution of corticosteroids, immunosuppressants and renal replacement therapy allows greater emphasis on long-term management issues. In particular, the recent focus has been on therapies to treat nephritis with fewer adverse effects of cyclophosphamide-including immunosuppressive regimens. Mycophenolate mofetil (MMF) has been used in the field of transplantation for more than 10 years. Following initial anecdotal reports describing benefits of MMF in the treatment of lupus nephritis, randomized, controlled trials have established a role for MMF in the treatment of lupus nephritis. MMF use to treat other lupus manifestations has been evaluated only in anecdotal case reports or series with few well-designed trials. Issues complicating clinical trial design in lupus including appropriate use and interpretation of activity and damage indices, comparable remission and response criteria and stratification of high risk populations have been the subject of much discussion and emerging consensus. As long-term outcomes in lupus improve, the toxicity of therapy and risk of relapse become increasingly important determinants of choice of therapeutic agents.

Cyclophosphamide↗
PubMed2004

SaGAS, the Short and Graphic Ability Score: an alternative scoring method for the motor components of the Multiple Sclerosis Functional Composite.

The timed performances of the 10-m timed walk (TMTW) and the nine-hole peg test (NHPT) of 881 consecutive patients with multiple sclerosis (MS) undergoing a rehabilitation stay, were expressed as a logarithmic function of time in two subscores to form a composite score called the Short and Graphic Ability Score (SaGAS). The subscores (sS) were constructed in such a way that any interval of 0.5 unit corresponds to a change of 25% in the tests. The SaGAS was computed as the mean of four subscores: SaGAS = (2 x TMTWsS + NHPTsS right hand + NHPTsS left hand). With the aid of a nomogram, the timed values of the tests are easily transformed into the corresponding subscores, which are then displayed graphically to facilitate follow-up over time. The correlation coefficients between the SaGAS and the two motor components of the MS Functional Composite (MSFC) (r = 0.987), the Expanded Disability Status Scale (EDSS)(r = -0.83), the Nottingham EADL Index (r = 0.80) and the Rivermead Mobility Index (RMI) (r = 0.90) were all statistically significant (P < 0.001), supporting the validity of the measure. SaGAS had a similar sensitivity to the RMI, but was significantly more sensitive than the EDSS in detecting changes occurring during the rehabilitation stay (14.9% versus 5.0%; P < 0.001) and over a one-year follow-up (35.3% versus 19.7%; P < 0.001). Compared with the motor components of the MSFC, with which it shares several features, SaGAS has several advantages: it does not depend on the stratification of the study population; it does not skew the results of the NHPT towards improvement at the lower end; and it offers an independent assessment of both hands. SaGAS is a simple, intuitive, nonphysician-based measure, which could provide consistent scoring in future clinical trials.

Activities of Daily Living↗
PubMed2001

Prognostic value of ultrasonographic measurement of carotid intima media thickness in dialysis patients.

High-resolution carotid ultrasonography is considered a fundamental technique for the investigation of the vascular system. However, it is still very unclear whether ultrasonographic studies of carotid arteries are useful for the prediction of cardiovascular events in patients with end-stage renal disease. The prediction power of carotid ultrasonography for all-cause and cardiovascular mortality was tested in a cohort of 138 patients receiving chronic dialysis treatment (91 receiving hemodialysis treatment and 47 receiving continuous ambulatory peritoneal dialysis treatment; follow-up, 29.8 +/- 15.0 mo), and the relationship between this parameter and alterations in left ventricular mass (LVM) and geometry was examined. On univariate analysis, intima media thickness (IMT) was directly related to LVM as well as to the absolute and relative thicknesses of LV walls but independent of LV end-diastolic volume. Data analysis based on LV geometry patterns revealed that patients with concentric hypertrophy were those with the highest IMT. The internal diameter of the common carotid artery (DCCA) was also related to concentric hypertrophy, but the strength of this relationship was of borderline significance (P = 0.06). During the follow-up period, 63 patients died: 32 (51%) of them of cardiovascular causes. IMT was significantly higher (P = 0.006) in patients who died of cardiovascular causes (1.10 +/- 0.21 mm) than in patients who survived (0.99 +/- 0.24 mm), In a Cox regression model, this parameter turned out to be an independent predictor of cardiovascular death, and it retained an independent effect in a model that included LVM. Treatment modality failed to independently predict this outcome. The risk of cardiovascular death was progressively higher from the first IMT tertile onward. DCCA failed to predict cardiovascular outcomes. IMT in dialysis patients is associated with LV concentric hypertrophy and is an independent predictor of cardiovascular death. IMT may be usefully applied for risk stratification in the dialysis population.

Aged↗