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At least 1,009 records · Page 56Linked to original sources
PubMed1993

Risk stratification and prognosis of patients treated with amiodarone for malignant ventricular tachyarrhythmias after myocardial infarction.

Seventy-seven consecutive patients (mean age 62 years) with episodes of sustained ventricular tachycardia (VT) or ventricular fibrillation (VF) after acute myocardial infarction (AMI) were evaluated to assess the long-term efficacy of first-line amiodarone treatment and to identify clinical and laboratory factors associated with a high risk of death or arrhythmia recurrence. The presenting arrhythmia was VT in 41 cases (53%) and VF in 36 (47%). VT or VF occurred between the 4th and 90th day after AMI in 45 cases (58%) and later (more than 90 days) in the remaining 32 (42%). The mean number of arrhythmic episodes was 4.2. Forty patients (52%) were in New York Heart Association (NYHA) class I or II, and 37 (48%) were in class III or IV. Mean left ventricular ejection fraction was 32%; ventricular aneurysm was present in 41 subjects. Most patients had multivessel coronary artery disease. Amiodarone was administered as a first-choice drug in all patients, in combination with other antiarrhythmic drugs in 14. By ventricular stimulation after loading doses of amiodarone, sustained VT was inducible in 46 (62%) and noninducible in 28 (38%). During a mean follow-up of 28 months the incidence of cardiac mortality at 1, 3, and 5 years was 21%, 37%, and 47%; of sudden death was 7%, 19%, and 23%; of nonfatal VT recurrence was 13%, 13%, and 24%, respectively. The overall incidence of amiodarone side effects was 35%.2+ was a weak predictor only by univariate analysis (p = 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1982

Response characteristics and stratification of tectal neurons in the toad Bufo bufo (L.).

In the optic tectum of Bufo bufo the activity of single neurons was recorded during the presentation of moving visual stimuli. The location of the recorded cells was marked iontophoretically by means of alcian blue dye. A total of 132 cells were studied, most of which showed clear differences within their responses to a square and to rectangles oriented either horizontally or vertically. The cells were found primarily within the tectum layers 8 and 6. The majority of them preferred the square to the horizontal bar, and this stimulus to the vertical one. Another group responded best to the horizontal rectangle. Relatively few cells were found in which the vertical stimulus was preferred to the horizontal one. A considerable number of tectal cells showed a change of stimulus preference if the stimulus velocity was changed. No clear correlation between response types and anatomical distribution within the tectum layers could be found.

Animals↗
PubMed1990

Risk stratification after percutaneous transluminal coronary angioplasty.

Approximately 20-30% of patients who undergo elective percutaneous transluminal coronary angioplasty (PTCA) require a second angioplasty within 12 months. A significant proportion of patients develop clinical cardiac events during the first year following the initial procedure. The present investigation was undertaken to establish a statistical model for predicting such events. The study group consisted of 100 patients who underwent elective PTCA at the University of Alberta Hospital. All patients were prescribed nifedipine (10 mg tid) and aspirin (325 mg daily) in addition to other medications determined by the attending cardiologist. The patients were reviewed 10 weeks after the procedure and again at the end of 1 year. The follow-up was completed on 96 patients. Within the first year, forty-five experienced cardiac events (1 death, 5 myocardial infarctions, 4 bypass surgeries, 22 repeat PTCAs). These events occurred in 29 patients. An additional 16 patients experienced significant anginal symptoms. A statistical model based upon the patients' perception of symptoms immediately after the procedure, history of hypertension, vessel subjected to PTCA, ejection fraction pre-PTCA, and occurrence of intimal dissection during PTCA was used to identify patients likely to develop cardiac events. Overall, the model classified 72% of the patients (with and without events). Such a statistical model could be used to identify patients who should be subjected to an enhanced degree of cardiologic surveillance in a rehabilitation program.

Aged↗
PubMed1995

Stratification of palpable and nonpalpable breast cancer by method of detection and age.

BACKGROUND: Methods used to diagnose breast cancer in women under the age of 50 years are somewhat controversial. To determine the relationship between type and stage of breast cancer, clinical presentation, and age, we reviewed breast cancer diagnosed at our institution during a recent 3-year period. METHODS: Records from 589 consecutive excisional biopsies and 372 needle placement biopsies performed over a 3-year period were reviewed. Carcinomas were staged according to the TNM system and results compared using chi 2. RESULTS: Breast carcinoma was diagnosed in 118 women during the study period, 33% in patients under 50 years of age. Breast cancer diagnosed by mammography in all age groups was more likely to be noninvasive than that diagnosed by physical examination (p < 0.05). The few invasive cancers diagnosed by mammography in women under age 50 were lower in stage than those diagnosed by physical examination, although not by a statistically significant amount (p = 0.125). Breast cancer diagnosed by mammography in women 50 years and older was significantly lower in stage than that diagnosed by physical examination (p < 0.05). CONCLUSIONS: Invasive carcinoma detected as a nonpalpable lesion by mammography was earlier in stage than invasive carcinoma detected by physical examination, including in women under 50 years of age, although the number of invasive cancers detected in younger women was quite small. The role of mammography in this younger age group remains to be defined.

Age Factors↗
PubMedDate not supplied

Risk stratification in the elderly patient after coronary artery bypass grafting: the prognostic value of radionuclide cineangiography.

BACKGROUND: Recent data have shown that assessment of left ventricular function by radionuclide cineangiography (RNCA) predicts survival and cardiac events among non-age-selected patients who have previously undergone coronary artery bypass grafting (CABG). However, the prognostic value of this noninvasive approach is not known for elderly patients who now undergo CABG with progressively increasing frequency and who survive longer because of operation. Such easily applied prognostic indexes may be useful to determine whether survival benefits are likely to be maintained or additional therapy should be considered. METHODS AND RESULTS: To obtain information on factors related to long-term survival and cardiac events among elderly patients after CABG and, specifically, to determine the prognostic implications of left ventricular performance at rest and during exercise for predicting all causes of death, major nonsurgical cardiac events (death or myocardial infarction), and event-free or surgery-free survival, we evaluated the late postoperative course of 41 patients, aged 65 years and older, who had undergone RNCA 1 month or more (mean 2.3 +/- 2.4 years; range 0.1 to 9 years) after CABG. Average follow-up among patients with event-free survival was 8.8 years after index radionuclide assessment. During follow-up 13 patients died with no known intercurrent event, five patients had nonfatal myocardial infarctions, and five underwent late (> or = 3 months after RNCA) repeat CABG or percutaneous transluminal coronary angioplasty. Log-rank comparisons of Kaplan-Meier product limit estimate curves identified only left ventricular ejection fraction at rest as significantly predictive of survival (p < 0.04). Patients with left ventricular ejection fraction at rest of less than 45% had a 7.8% average annual mortality risk, which was more than three times that of patients with normal resting function. Statistical trends also were found between mortality rates and completeness of revascularization (p < 0.06), major nonsurgical cardiac events and extent of anatomic disease (p < 0.08), and event-free or surgery-free survival and our index of completeness of revascularization (p = 0.08) and age at index RNCA (p < 0.07). CONCLUSIONS: Assessment of left ventricular ejection fraction at rest is prognostically useful after CABG among elderly patients. The efficacy and timing of this approach should be confirmed in further investigations with larger and more varied patient subgroups.

Aged↗
PubMed2004

Arrhythmia risk stratification with regard to prophylactic implantable defibrillator therapy in patients with dilated cardiomyopathy. Results of MACAS, DEFINITE, and SCD-HeFT.

To date, generally accepted indications for prophylactic defibrillator implantation in patients with dilated cardiomyopathy do not exist. Recently, the Marburg Cardiomyopathy Study (MACAS) revealed left ventricular ejection fraction to be the only significant arrhythmia risk predictor in a relatively large patient population with dilated cardiomyopathy. Meanwhile, the preliminary results of two prospective randomized trials evaluating prophylactic defibrillator therapy in dilated cardiomyopathy have been reported. The Defibrillators in Nonischemic Cardiomyopathy Treatment Evaluation study (DEFINITE) randomized 458 patients with a history of symptomatic heart failure, a left ventricular ejection fraction < or = 35% and arrhythmias on Holter to an ICD versus no ICD. As a result, ICD therapy was associated with a significant reduction of arrhythmic deaths, which failed to result in a significant decrease in total mortality due to an insufficient number of patients in DEFINITE. The Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT) was a three-arm study comparing placebo to amiodarone to prophylactic ICD therapy in a total of 2,521 patients with ischemic cardiomyopathy (51%) or nonischemic dilated cardiomyopathy (49%). All patients in SCD-HeFT had a left ventricular ejection fraction inverted exclamation mark U 35% despite optimized medical heart failure therapy. SCD-HeFT showed a significant reduction of total mortality in the ICD group, whereas amiodarone did not improve survival.

Arrhythmias, Cardiac↗
PubMed2004

Risk stratification by the "EPA+DHA level" and the "EPA/AA ratio" focus on anti-inflammatory and antiarrhythmogenic effects of long-chain omega-3 fatty acids.

The identification of risks associated with sudden cardiac death requires further investigations. The question was addressed whether parameters can be established which not only describe an increased risk for an enhanced electrical instability of the heart but also of inflammatory events underlying plaque rupture. Emphasis is placed on dose-dependent effects of the long-chain omega-(omega-)3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Since free acids of EPA and DHA are required for most of their biological effects, it appears essential not only to build up stores in the body for release of these fatty acids, but also to provide a sustained uptake of EPA and DHA in the form of ethyl esters. In contrast to rapidly absorbed triacylglycerols from fish, ethyl esters are taken up more slowly within 24 h. For the administration of 1 g/day highly purified EPA+DHA ethyl esters (Omacor) to healthy volunteers, it is shown that EPA is increased from 0.6% to 1.4% within 10 days, while DHA is increased from 2.9% to 4.3%. After withdrawal, EPA and DHA approach baseline values within 10 days. A gas chromatographic procedure was established which requires only 10 microl of whole blood for the identification of more than 35 fatty acids. Evidence is summarized strengthening the concept that a low "EPA+DHA level" presents a risk for sudden cardiac death and that the administration of 840 mg/day of EPA+DHA ethyl esters raises the "EPA+DHA level" to approximately 6% that is associated with a marked protection from sudden cardiac death. For reducing pro-inflammatory eicosanoids and cytokines, a higher "EPA+DHA level" is required which can be achieved with an intake of 2-4 g/day of 84% EPA+DHA ethyl esters. For assessing influences from pro-inflammatory eicosanoids and cytokines, the EPA/arachidonic acid ratio ("EPA/AA ratio") was identified as diagnostic parameter. To assess the dietary EPA+DHA intake, fatty acids were determined in fish dishes of the cafeteria of the Philipps University Hospital Marburg, Germany. The EPA+DHA content of the popular Alaska Pollock was 125 +/- 70 mg/100 g. A once daily fish dish can thus not provide the 840 mg/day EPA+DHA administered in the GISSI Prevention Study in the form of ethyl ester which markedly reduced the risk of sudden cardiac death in postmyocardial infarction patients. Nonetheless, at least two preferably oily fish meals per week should be consumed as preventive measure by persons without coronary artery disease. With documented coronary heart disease, it was advised to consume approximately 1 g/day of EPA+DHA.

Administration, Oral↗
PubMed2004

[Marburg model for optimization of stratification of the anaesthesiological risk].

The perioperative risk is mostly determined by the patient's cardiological condition and the type of surgical intervention. Therefore it is very important during the premedication visit to identify patients with cardiac risk factors. We suggest that patients be classified into three risk classes according to the ACC/AHA recommendations in advance of the preanaesthetic visit. The majority of patients with a low or medium anaesthesiological risk profile could be identified by simple asking, e.g. whether they are able to exercise physically for 20 min or to climb two staircases without resting. For the lowest risk no further evaluation is necessary. For the medium risk class an additional preoperative diagnosis or for the higher risk class a cardiological consultation or even postoperative intensive care monitoring could be necessary. The aim of such a system is to always minimise the rate of perioperative complications and delays in scheduled surgery.

Anesthesia↗
PubMed2006

Spatial stratification of soil bacterial populations in aggregates of diverse soils.

Most soil microbial community studies to date have focused on homogenized bulk soil samples. However, it is likely that many important microbial processes occur in spatially segregated microenvironments in the soil leading to a microscale biogeography. This study attempts to localize specific microbial populations to different fractions or compartments within the soil matrix. Microbial populations associated with macroaggregates and inner- versus total-microaggregates of three diverse soils were characterized using culture-independent, molecular methods. Despite their relative paucity in most surveys of soil diversity, representatives of Gemmatimonadetes and Actinobacteria subdivision Rubrobacteridae were found to be highly abundant in inner-microaggregates of most soils analyzed. By contrast, clones affiliated with Acidobacteria were found to be relatively enriched in libraries derived from macroaggregate fractions of nearly all soils, but poorly represented in inner-microaggregate fractions. Based upon analysis of 16S rRNA, active community members within microaggregates of a Georgian Ultisol were comprised largely of Gemmatimonadetes and Rubrobacteridae, while within microaggregates of a Nebraska Mollisol, Rubrobacteridae and Alphaproteobacteria were the predominant active bacterial lineages. This work suggests that microaggregates represent a unique microenvironment that selects for specific microbial lineages across disparate soils.

Actinobacteria↗
PubMed2006

FDG-PET status following chemoradiotherapy provides high management impact and powerful prognostic stratification in oesophageal cancer.

PURPOSE: The purpose of this study was to evaluate the impact of FDG-PET following chemoradiotherapy (CRT) on treatment planning and survival in patients with oesophageal cancer (OC). METHODS: Fifty-three consecutive OC patients had a post-treatment PET scan to evaluate tumour response to CRT prior to possible surgery. Baseline pre-CRT PET was performed in 33 patients. Prospectively recorded post-CRT management plans were compared with post-PET treatment. High impact was defined as a change in treatment intent or modality. Survival was analysed using the Kaplan-Meier product limit method and Cox proportional hazards regression model. RESULTS: After completion of CRT, 23/53 patients (43%) achieved complete metabolic response (CMR), as compared with only four (8%) with complete response on computed tomography. High PET impact was observed in 19 patients (36%). CMR was strongly predictive of survival (p<0.008) on multivariate analysis. CMR patients in whom resection was not performed had comparable survival to those (CMR and non-CMR) who underwent resection. CONCLUSION: The use of post-treatment FDG-PET for assessment of tumour response after CRT changed the clinical management of more than one-third of OC patients. CMR status as assessed by PET powerfully stratified prognosis. Even in the absence of a baseline study, normalisation of uptake at all sites of known tumoral involvement carries a good medium-term prognosis.

Adult↗
PubMed1996

Severity stratification and outcome prediction for multisystem organ failure and dysfunction.

Multiple organ system failure or dysfunction (MOSF/MODS) remains a major cause of morbidity and mortality in hospitalized adults. Among intensive care unit (ICU) patients the extent of physiologic derangement, the type of associated disease or injury, increasing age, and life-threatening comorbid conditions are the major determinants of risk for developing MOSF and for survival during the 1980s. Hospital mortality for patients with a single organ system failure (OSF) lasting more than 1 day approached 40%; and for those with two OSFs hospital mortality increased to 60%. These outcomes did not change over the decade. For patients with three or more OSFs persisting after 3 days of OSF, however, data suggest that between 1982 and 1990 the mortality has been reduced from 98% to 84% (p = 0.0003). Because of variations in the types and combinations of OSFs, associated disease, and extent of physiologic derangement, it is difficult to interpret variations in mortality among patients with one or more OSFs defined using categorical criteria. For this and other reasons, outcome prediction based on a comprehensive assessment of patient risk factors is a more sensitive, specific, useful approach to quantifying MODS than a simple count of the number and duration of OSFs. Because repeated assessment of risk factors during subsequent ICU days reflects complications and response to therapy, daily outcome predictions are even more precise than estimates at ICU admission. The ability to more accurately predict survival from MODS/MOSF can improve our ability to test new therapies, evaluate how outcome has changed over time, and assess the efficacy of supportive therapy for individuals.

Adult↗
PubMed2005

[Histological grading of soft tissue sarcomas: stratification of G2-sarcomas in low- or high-grade malignant tumors].

Histological grading according to one of the proven systems, e.g. that of the FFCCS, leads to the definition of different prognostic risk groups. Prerequisite is a precise typing of the tumors, if necessary by immunohistochemical and molecular-pathological methods. The therapeutic decision is dependent on the presence either of a low- or high-grade malignant tumor: With low-grade sarcomas surgery has priority, with high grade tumors usually chemo- and/or radiotherapy are indicated. With the latter, also better therapeutic response is reported. Therefore, conversion of a 3-grade into a 2-grade system has to be carried out by including the tumor localization as prognostic parameter. Thereby, the large group of G2-sarcomas with intermediate malignancy can be stratified. Superficial G2-sarcomas are considered to be low grade and deep G2-sarcomas high grade malignant. Immunohistochemical staining of tumor cell nuclei with Ki67/MIB1 allows a more standardized and precise grading. The ultimate aim, not to define risk groups, but to predict the prognosis for individual patients, possibly could be reached someday by molecular diagnostic methods.

Humans↗