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PubMed2007

[Stratification with respect to hormone receptor and HER 2/neu in the treatment of metastatic breast cancer; sensitivity to taxane].

Of 231 patients with recurrent or metastatic breast cancer treated in Hiei Hospital between January 2001 and March 2005, for whom data on hormone receptor (HR) and HER 2/neu were available, we retrospectively analyzed the association of the response rate with HR and HER 2 in 172 patients treated with taxane in whom the treatment response could be evaluated. Among the patients treated with taxane alone,the response rates were 37.5% (n=67) in the HR (+) patients and 14.6% (n=41) in the HR (-) patients (p=0.0131). In particular, taxane resistance was suggested in the HR (-)/HER 2 (-) patients (response rate: 4.2%, n=24). Concerning combination therapy with trastuzumab and taxane, the response rate were 52.8% in the HR (+)/HER 2 (+) patients and 60.4% in the HR (-)/HER 2 (+) patients. In 27 of these patients, single therapy with taxane was switched to combination therapy with taxane and trastuzumab after they became resistant to taxane, and 8.3% of the HR (+)/HER 2 (+) patients and 53.3% of the HR (-)/HER 2 (+) patients responded to this combination therapy (p=0.0192), suggesting the synergistic effects of the two agents in HR (-)/HER 2 (+) patients. Therefore, HR and HER 2 were associated with the sensitivity to a chemotherapeutic agent, taxane. Stratification with respect to HR and HER 2 is important in the treatment of metastatic breast cancer. In particular, therapeutic strategies for HR (-)/HER 2 (-) patients with a poor prognosis must be established in the future.

Antibodies, Monoclonal↗
PubMed1992

Autonomic nervous system and sudden cardiac death. Experimental basis and clinical observations for post-myocardial infarction risk stratification.

The analysis of the autonomic control of the heart, by means of indirect markers, may represent a new approach for identifying patients at higher risk for sudden cardiac death after a myocardial infarction. This possibility is based on the evidence that autonomic responses during acute myocardial ischemia are a major determinant of the outcome (i.e., occurrence of ventricular fibrillation or survival). Specifically, sympathetic activation can trigger malignant arrhythmias, whereas vagal activity may exert a protective effect. Several experimental observations have provided new insights on the relation between sympatho-vagal interactions and the likelihood for the occurrence of ventricular fibrillation. In an established experimental model for sudden death involving conscious dogs with a healed myocardial infarction, either depressed reflex chronotropic responses during a blood pressure rise or reduced variability of heart rate (respectively, markers of reflex and tonic cardiac vagal activity) identify dogs at greater risk to develop malignant arrhythmias during a new ischemic episode. In anesthetized cats, direct neural recording of vagal activity to the heart confirmed that vigorous reflex vagal activation during acute myocardial ischemia is associated with protection from ventricular fibrillation. Furthermore, in these experiments the reflex neural response to acute myocardial ischemia was predicted by the analysis of baroreflex sensitivity. The antifibrillatory effect of vagal activation is confirmed by the prevention of ventricular fibrillation during acute ischemia in dogs susceptible to sudden cardiac death by direct electrical stimulation of the right vagus. The clinical counterpart of these experimental data lies in three separate prospective studies showing a higher cardiac mortality in patients who after a myocardial infarction have a depressed baroreflex sensitivity or a decreased heart rate variability. A definitive answer on the role that the analysis of markers of cardiac vagal activity may play in risk stratification of patients with coronary artery disease should be provided by Autonomic Tone and Reflexes After Myocardial Infarction (ATRAMI), an ongoing prospective study. In ATRAMI, baroreflex sensitivity and heart rate variability will be assessed within 20 days after a myocardial infarction in 1,200 patients enrolled in Europe, U.S.A., and Japan with a minimum follow up of one year.

Animals↗
PubMed1991

[Comparison of exercise thallium-201 perfusion scintigraphy and coronarography in the prognostic stratification of patients with post-infarction residual ischemia].

The goals of this study were: 1) to determine and compare the prognostic utility of exercise 201Thallium scintigraphy with coronary angiography in patients with residual ischemia at the symptom limited bicycle exercise testing performed at hospital discharge after a first uncomplicated acute myocardial infarction 2) to verify the ability of perfusion scintigraphy to identify better than coronary angiography a subset of these patients at low risk for future events, despite the ischemic response at the exercise stress testing. Accordingly, follow-up data were obtained prospectively for 72 consecutive patients with adequate left ventricular rest systolic function, and with exercise induced greater than or equal to 1 mm ST-segment depression and/or typical angina pectoris. A planar 201Thallium scintigraphy and coronary angiography were performed within 2 months after acute myocardial infarction. By 31 +/- 29 months 38 patients had no events, while 34 experienced a cardiac event: 3 died of cardiac causes, 2 had nonfatal recurrent myocardial infarction, 29 were rehospitalized for severe class III or IV angina pectoris (4 were treated medically, 25 were revascularized: 20 had coronary bypass surgery, 5 coronary angioplasty). Each of the 3 angiographic classification of coronary artery disease (number of vessels with greater than or equal to 70% reduction of luminal diameter, jeopardy score and Gensini score) accurately identified patients with subsequent cardiac event by Mantel and Cox analysis (respectively p = 0.01, p = 0.0000, p = 0.002). Among 201Thallium variables, the number of segments demonstrating redistribution on delayed images (p = 0.0000), the number of segments with persistent defect (p = 0.0003) and increased 201Thallium uptake by the lungs (p = 0.0100) effectively stratified the probability of survival by the same analysis. Furthermore, the number of perfusion defects, either transient or persistent, with exercise 201Thallium scintigraphy provide additive prognostic information to any of the 3 angiographic coronary artery disease classifications considered. On the contrary, when 201Thallium stress findings are known, coronary angiography data in general are not additive in risk stratification. 17 patients with no reversible perfusion defect remained stable at follow up (52 +/- 28 months) despite development of typical angina pectoris (11/17) and/or ischemic ST segment depression (12/17) during exercise testing.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1991

Value of planar 201Tl imaging in risk stratification of patients recovering from acute myocardial infarction.

Although exercise ECG testing has been shown to have important prognostic value after acute myocardial infarction, exercise 201Tl scintigraphy offers several potential advantages, including: 1) increased sensitivity for detecting residual myocardial ischemia; 2) the ability to localize ischemia to a specific area or areas subtended by a specific coronary artery; 3) the ability to identify exercise-induced left ventricular dysfunction, which is manifested by increased lung uptake or transient left ventricular dilation; and 4) more reliable risk stratification of individual patients. The more optimal prognostic efficiency of 201Tl scintigraphy partially results from the fact that the error rate in falsely classifying patients as low risk is significantly smaller with 201Tl scintigraphy than with stress ECG. Because of these substantial advantages, there seems to be adequate rationale for recommending exercise perfusion imaging rather than exercise ECG alone as the preferred method for evaluating mortality and morbidity risks after acute myocardial infarction.

Angiography↗
PubMed1991

Risk stratification after myocardial infarction with exercise and Doppler echocardiography.

Exercise testing early after myocardial infarction has been shown to be of further risk stratification value among otherwise low-risk patients on the basis of an uncomplicated clinical course. The addition of cardiac imaging modalities to exercise testing has augmented this capacity. Exercise echocardiographic imaging before and immediately after treadmill exercise can be accomplished in 85-95% of patients. New or worsening wall motion abnormalities identify 63-80% of patients who will suffer cardiac events and correctly predict 78-95% of those who will not. In addition, exercise echocardiography can detect multivessel coronary artery disease with a sensitivity of 80% and a specificity of 90%. These results are superior to those obtained by analyzing global left ventricular function during exercise, exercise aortic Doppler velocity profiles, or exercise electrocardiography. How exercise echocardiography compares with 201Tl perfusion imaging after myocardial infarction awaits a systematic study. Therefore, the choice between exercise echocardiography and perfusion imaging depends on physician preference, availability, cost, and service.

Echocardiography, Doppler↗
PubMed1991

Risk stratification after myocardial infarction. Clinical overview.

Many patients with an acute myocardial infarction can be stratified into subgroups that are at high risk for morbidity and mortality on the basis of clinical characteristics that indicate recurrent myocardial ischemia, persistent left ventricular dysfunction, and/or recurrent cardiac arrhythmias. In patients with uncomplicated myocardial infarction the assessment of symptoms, physical findings, and ECG changes during predischarge exercise testing often identifies patients at increased risk for further cardiac events. Because of the suboptimum sensitivity and specificity of the exercise ECG for detecting myocardial ischemia, myocardial perfusion imaging with 201Tl and/or assessment of global and segmental ventricular function by two-dimensional echocardiography or radionuclide cineangiography during or immediately after exercise are often added to the predischarge risk stratification.

Arrhythmias, Cardiac↗
PubMed1991

[Prognostic stratification of non complicated acute myocardial infarct. Usefulness of the dipyridamole test with ecg-echo-thallium 201].

84 patients (pts) with recent first uncomplicated myocardial infarction underwent during the early post-infarction period, dipyridamole (D) test (EKG-ECHO-THALLIUM) and coronary arteriography in order to verify its feasibility, safety and usefulness in the detection of residual jeopardized but viable myocardium and in the diagnosis of multivessel disease. 69 pts performed a pre-discharge exercise test. During the execution of D test no major side effect occurred. The D-Echo was positive for residual ischemia in 41 pts (48.8%), the D-Thallium in 49 pts (58.3%) and the exercise test in 30 pts (43.5%). Both the imaging techniques allow the recognition of viable myocardium within the infarct zone (homozonal positivity) or outside the infarct zone (heterozonal positivity). The sensibility and specificity for multivessel disease are, respectively: with D-echo 50% and 100%; with D-thallium 60% and 100%; with exercise test 48% and 63%. D test has better diagnostic accuracy than exercise test in detecting multivessel disease; in particular we emphasized the excellent specificity of D-echo and D-thallium test. Poliparametric approach with D-test and exercise test gives a better stratification of the ischemic post-infarction risk.

Adult↗
PubMed1991

Risk stratification and outcome assessment of the adult cardiac surgical patient.

Comparisons between institutions are already occurring, and comparisons between individual providers may also become a reality. In spite of the negative views of such comparisons, they are likely to be mandated because of pressure from health care regulators, insurers, and patients. Despite awareness of the importance of demographic variables and concurrent medical problems in influencing outcome, valid comparisons are presently difficult to conduct in the open heart surgical population. Current methods of risk stratification each have limitations. A method for risk assessment based on multivariate analysis from a large group of patients that can be prospectively validated at multiple institutions would be valuable, not only for mortality rate comparisons, but also for patient counseling, research, and hospital management uses. Caution must be applied when using risk assessment in individual patients. Physicians need to be involved in the development of such severity stratifying systems, since inclusion of inappropriate or medically irrelevant data can influence the outcome of multivariate analyses. Ongoing research and evolution of scoring systems also need to occur since therapy changes over time. It is likely that models will need to be developed for application preoperatively, at ICU admission, and for the complex, long-term patient at 7 days or beyond, in order to fully inform medical decision-making.

Adult↗
PubMed1991

Risk stratification in angina pectoris.

Risk stratification of the patient with angina pectoris can be accomplished initially by the history, physical examination, and resting electrocardiogram. Noninvasive testing can add important prognostic information and identify patients who might benefit from revascularization procedures. An exercise electrocardiographic test usually is the initial test to determine risk, but exercise 201Th scintigraphy and exercise radionuclide angiography can provide important additional information regarding outcome in selected subsets of patients.

Angina Pectoris↗
PubMed1990

[Risk stratification after uncomplicated myocardial infarct: the usefulness of the echocardiographic-dipyridamole test].

To assess the value and safety of echo-dipyridamole test in risk stratification soon after an uncomplicated acute myocardial infarction, 56 consecutive patients were enrolled in a prospective study with a 1-year follow-up period for new coronary events. Echo-dipyridamole and symptom-limited ECG stress test were performed respectively 14 to 20 days and 4 to 5 weeks after acute event. Echo-dipyridamole test was performed administering 0.84 mg/kg iv of the drug in 10 min: any worsening of left ventricular regional wall motion was considered as a positive test. Up to December 1989, 43 out of 56 patients had their follow-up period completed: the infarction was anterior in 13 (30%), inferior in 22 (51%), non-Q wave in 8 (19%); mean age was 55 +/- 10; basal echocardiographic ejection fraction was 52 +/- 6%. There were no major complications during echo-dipyridamole test. Coronary events occurred in 7 patients (16%): reinfarction in 3, angina in 4; there were no cardiac deaths. A positive echo-dypiridamole test was observed in 12/43 patients (28%); sensitivity versus coronary events was 43%, specificity 75%, negative predictive value 87%. Ten out of 43 patients (23%) had positive and 9/43 (21%) non valuable ECG stress test: sensitivity versus coronary events was 50%, specificity 75%, predictive negative value 88%. The 2 tests showed no significant difference in detecting patients at risk of future coronary events.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Is noninvasive risk stratification sufficient, or should all patients undergo cardiac catheterization and angiography after a myocardial infarction?

From the foregoing discussion, it becomes apparent that although noninvasive risk stratification is a reasonable approach to assessment of patients following an uncomplicated myocardial infarction, the performance of early cardiac catheterization and angiography on nearly all such patients is not unreasonable and may in fact be the most practical approach. The basis for this rationalization may be summarized as follows: 1. Many subgroups will need early catheterization anyway a. Myocardial infarction complicated by recurrent ischemia, heart failure, or complex ventricular arrhythmias b. Patients receiving thrombolytic treatment c. "Young" patients (less than 50 years old?) d. "Older" patients (over ages 65 to 70?) in otherwise good medical condition e. Patients unable to exercise f. Patients with abnormal or inconclusive noninvasive test results (approximately 70 percent of patients) 2. Cardiac catheterization and angiography as a single test provides the two most powerful prognostic variables following myocardial infarction, namely, the extent of coronary artery disease and residual left ventricular function. This knowledge is reassuring to both physician and patient and allows for planning of optimal long-term management. 3. Certain limitations exist in noninvasive risk assessment strategies. 4. This approach need not be significantly more costly, if all tests are used wisely. The major risk inherent in the definition of the extent of coronary artery disease in all survivors of acute myocardial infarction might be the performance of unnecessary revascularization procedures (percutaneous transluminal coronary angioplasty or coronary bypass surgery). The burden rests with the individual clinician to (1) collect all useful and necessary data; (2) assess reliability and accuracy of various tests available at one's own institution; (3) avoid performing unnecessary and repetitive tests; (4) interpret the data in the proper context; and (5) counsel patients appropriately, correctly, and judiciously about their prognosis and therapeutic options. In this manner, all patients who might benefit appropriately from revascularization can be discovered early and offered this therapeutic option. Other patients can also be managed more appropriately; for example, those who are truly at very low risk (normal left ventricular function and either normal coronary arteries or "mild" coronary artery disease). However, it is most important to avoid unnecessary revascularization procedures. Although this discussion has focused on noninvasive and invasive testing following myocardial infarction, it is necessary to emphasize that comprehensive management of coronary artery disease and its complications should not be neglected in these patients; for example, control or amelioration of risk factors for coronary artery disease is mandatory in all these patients, and in their families as well.

Aged↗
PubMed1990

Recent trends in the process of stratification.

Using the 14 annual cross-sections from the General Social Survey, we specify a "basic model" of attainment and describe the year-by-year fluctuations in its parameters. The results are partially consistent with theories describing the gradual growth of universalistic patterns of stratification and mobility. Under a linear model of educational achievement, we find that the direct effects of race are weakening and the returns to class-based advantages are declining in tandem. The contours of the socioeconomic "gender gap" are also changing in important ways, with the male intercept declining at a rapid pace and the female term registering small and insignificant year-by-year gains. At the same time, the returns to experience and schooling are increasing for men, whereas the corresponding returns for women have remained stable over the 15-year period. This pattern of interaction effects implies that the size of the gender gap varies over time and across different population groups.

Career Mobility↗
PubMed1990

Risk stratification and long-term results after surgical treatment of carcinomas of the thoracic esophagus and cardia. A 25-year retrospective study.

During 25 years (1960 to 1984), 657 patients (aged 22 to 91, mean 66 years) were operated on for carcinomas (squamous cell, n = 230; adenocarcinoma, n = 399; anaplastic, n = 28) of the thoracic esophagus (n = 347) or gastric cardia (n = 310). Esophagogastrectomy was accomplished in 514 patients, of whom 94% (n = 481) had an "inkwell" esophagogastrostomy performed. The hospital mortality rate (less than or equal to 30 days) was 19% and the 5-year cumulative survival rate was 9% +/- 1% (standard error). A Cox regression analysis enabled a detailed risk stratification of the patients. T, N, and M class and age were the strongest predictor variables. The general status of the patients, including pulmonary disease, also had a strong prognostic influence. Eight risk groups were identified having 1-year and 5-year survival rates of 71%/41% (n = 35), 69%/24% (n = 80), 47%/11% (n = 125), 30%/6% (n = 139), 12%/0% (n = 105), 6%/0% (n = 71), 2%/0% (n = 57), and 0%/0% (n = 45) (p less than 0.0001). Hospital mortality (from 6% to 42%) and complication rates increased significantly from the low-risk to high-risk groups. Comparisons with survival rates of background populations matched to each of the first four risk groups indicated that the benefit of surgical treatment may be underestimated if only patient survivals are judged. Use of modern endoscopic and noninvasive tests may yield a reliable TNM classification without surgical exploration. Given the extremely poor prognostic outlook together with high hospital mortality and complication rates of the four last risk groups, an aggressive surgical approach with resection whenever possible can no longer be regarded rational. Selection for surgical treatment should be based on a detailed risk estimation that takes into account both TNM classification and general patient status.

Adenocarcinoma↗
PubMed1988

After the myocardial infarction: a review and approach to risk stratification.

Each patient who is stricken with a myocardial infarction should be evaluated with respect to future risk. Risk stratification should be carried out early after the acute infarction since the majority of excess deaths occur early after discharge. Clinical observations and several properly selected noninvasive procedures will classify most patients into high or low risk.

Cardiac Complexes, Premature↗
PubMed1989

A method of uniform stratification of risk for evaluating the results of surgery in acquired adult heart disease.

The purpose of the study was to devise a method of stratifying open-heart operations into levels of predicted operative mortality, using objective data that are readily available in any hospital. Following univariate regression analysis of 3,500 consecutive operations, 14 risk factors were chosen that met these conditions. A few factors were excluded because they were insufficiently objective or not always available. An additive model was constructed, using the factors chosen, to calculate the probability of mortality within 30 days. The method was then tested prospectively in 1,332 open-heart procedures at the Newark Beth Israel Medical Center. Patients were categorized in five groups of increasing risk: good (0-4%), fair (5-9%), poor (10-14%), high (15-19%), and extremely high (greater than or equal to 20%). The correlation coefficient of anticipated and observed operative mortality, using the additive model, was 0.99. The operative mortality also correlated closely with complication rates and length of hospital stay. The additive model was compared with a second model based on logistic multiple regression; the resulting correlation coefficient was 0.85. The method was also tested at two other hospitals; although their sample sizes were smaller, the outcomes in each risk group were comparable with those at this institution. The collection of data proved to be acceptably simple for all three centers. This study demonstrates that it is possible to design a simple method of risk stratification of open-heart surgery patients that makes it feasible to analyze operative results by risk groups and to compare results in similar groups between institutions. Wider application of the system is recommended.

Adult↗
PubMedDate not supplied

Risk-benefit stratification as a guide to lidocaine prophylaxis of primary ventricular fibrillation in acute myocardial infarction: an analytic review.

Early investigators suggested that ventricular fibrillation without heart failure in acute myocardial infarction was reliably preceded by warning arrhythmias, and that suppression of such arrhythmias with intravenous lidocaine could avoid the need for resuscitation. While the efficacy and safety of lidocaine have been substantiated, the reliability of warning arrhythmias as predictors for primary ventricular fibrillation has not. We present data showing that the risk of primary ventricular fibrillation is most dependent on the patient's age and the interval since the onset of his symptoms, rather than on the presence of warning arrhythmias. We have estimated that lidocaine prophylaxis would have to be given to about 12 patients in the highest risk group (patients under age 50 and within six hours of the onset of symptoms), compared to about 400 patients in the lowest risk group (patients above age 70 and more than 24 hours since the onset of symptoms), to prevent one episode of primary ventricular fibrillation in each group. We propose that these risk stratifications, as adapted to the conditions in specific hospitals, provide the most rational approach to lidocaine prophylaxis of primary ventricular fibrillation.

Age Factors↗
PubMed1985

Risk stratification after myocardial infarction.

Functional risk stratification has been a fruitful new approach to classification and management of patients with acute myocardial infarction. Risk is divided into the functional categories: (1) left ventricular dysfunction; (2) ventricular arrhythmias; and (3) ischemia. Diastolic and systolic left ventricular dysfunction and perhaps aneurysm formation are independent indicators of death. Holter ECG recording of spontaneous ventricular arrhythmias or ventricular arrhythmias induced by programmed ventricular stimulation can identify patients who have a higher risk of dying. Ischemic risk can be identified with accuracy in patients with first inferior myocardial infarction. Coronary angiography is indicated to establish ischemic risk for the following situations (1) angina pectoris with ST depression; (2) non-Q wave infarction (3) inferior infarct with positive exercise test; and (4) anterior infarction with left ventricular ejection fraction between 20% and 40%.

Angina Pectoris↗
PubMed1966

On the stratification of human bile and its importance for the solubility of cholesterol.

Stratification (layer formation) is noted in vitro in hepatic bile collected after interruption of the enterohepatic circulation. Hepatic bile is still layered after more than 12 hr when collected in this way (continuously or in fractions) in a bag made of a semipermeable membrane (simulating an atonic gall bladder) and concentrated. Cholesterol solubility is very slight in the upper layer. This phenomenon may be important for precipitation of cholesterol and the formation of gallstones, since the enterohepatic circulation is interrupted when bile is stored and concentrated in the gall bladder. This condition may be prolonged by temporary stasis, which has always been considered one of the main factors in the formation of gallstones.

Bile↗