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1.
S B Knoebel 《The American journal of cardiology》1985,56(5):32C-34C
When health care cost containment is tied to unit pricing, the system may become price-driven rather than care-driven. Although the incentives engendered by unit pricing may not necessarily result in practices detrimental to the young or the patient with relatively pure disease, the potential for adverse effects on the elderly, the poor and the chronically ill is real. Hospitals will soon emphasize quick turnover, efficiency and intensive care. Diagnostic evaluations and chronic disease care will be moved out of hospitals into physician owned-and-operated facilities and out-of-hospital settings, respectively. The health care system will fractionate, and quality control will require restructuring to achieve the present level of quality assurance. Cardiologists, as well as other physicians, will need to alter their teaching style and teaching locations. Better methods for predicting outcomes will need to be developed; we will no longer have the safety net of following a patient closely and altering management plans according to the patient's response. Cost containment may occur under diagnosis related groups, preferred provider organizations, health maintenance organizations and other prepaid or "capped" systems. There are, however, many issues relative to cost versus quality that need to be resolved if severe detrimental effects on care are to be avoided. 相似文献
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B F Waller B J Maron A A Del Negro J S Gottdiener W C Roberts 《The American journal of cardiology》1984,53(1):139-147
To assess the reliability of M-mode echocardiographic patterns of mitral valve prolapse (MVP) (echo MVP) in detection of morphologic evidence of MVP (morphologic MVP), operatively excised mitral valves and corresponding M-mode echocardiograms from 65 patients with chronic, severe, isolated, pure mitral regurgitation (MR) were studied. Of the 65 patients, 45 (69%) had echo MVP (either holosystolic or mid-to-late systolic prolapse patterns on preoperative M-mode echograms) and 42 (93%) of them had morphologic MVP; of the 3 without morphologic MVP, 2 had ruptured chordae tendineae from infective endocarditis and 1 had papillary muscle dysfunction from atherosclerotic coronary heart disease. Of the 20 patients without echo MVP, 14 (70%) had no morphologic MVP (9 had papillary muscle dysfunction from coronary heart disease, 4 had infective endocarditis on previous normal valves and 1 had rheumatic heart disease). Of the 48 patients with morphologic MVP, 42 (88%) had echo MVP and most had considerably dilated mitral anulae; the other 6 had ruptured chordae tendineae with less degrees of anular dilatation. Of the 17 patients without morphologic MVP, 3 had echo MVP (coronary artery disease in 1 and infective endocarditis on a previous normal valve in 2); of the 14 with neither echo nor morphologic MVP, 9 had papillary muscle dysfunction from coronary artery disease, 4 had infective endocarditis on previously normal valves and 1 had rheumatic heart disease. The patients with very dilated mitral anuli and leaflet areas generally had holosystolic (hammocking) patterns on echo; the patients with small anuli and leaflet areas usually had mid-to-late systolic (buckling) prolapse patterns. 相似文献
5.
Arunabha Ganguly Myron H. Weinberger John M. Passmore John A. Caras Rashid M. Khairi Clarence E. Grim James Edmonson C.Conrad Johnston 《Metabolism: clinical and experimental》1982,31(6):595-600
To evaluate the role of the renin-angiotensin-aldosterone system in the hypertension associated with primary hyperparathyroidism, we measured plasma renin activity and aldosterone concentration before and after maneuvers to suppress and stimulate this system in 11 hypertensive patients with primary hyperparathyroidism. We also measured plasma or urinary norepinephrine concentration to examine the role of catecholamines in the hypertension. The results were compared with an age- and race-matched control population. While the mean plasma aldosterone concentrations were normal, the mean plasma renin activity in response to furosemide stimulation was subnormal in subjects with hyperparathyroidism. Plasma or urinary norepinephrine concentrations were within the normal range. Thus a specific abnormality of the renin-angiotensin-aldosterone system or catecholamines could not be identified in these hypertensives with primary hyperparathyroidism. 相似文献
6.
Bundle branch block and sudden death 总被引:2,自引:0,他引:2
Gary R. Fisch Douglas P. Zipes Charles Fisch 《Progress in cardiovascular diseases》1980,23(3):187-224
It is clear from the available data that the prognosis for patients with chronic BBB depends to a large extent on the presence and etiology, as well as the severity, of the associated heart disease. In most patients, the terminal event is usually one of heart failure or the complication of coronary artery disease. In the absence of clinically detectable heart disease, the long-term prognosis for this group of patients is good.Patients with chronic bundle branch block Have been shown to have an incidence of ventricular arrhythmias greater than that found in a normal population. The mechanism of sudden death in any single unmonitored patient is speculative. Most patients dying suddenly, especially those with coronary artery disease, probably do so from ventricular fibrillation. Patients with documented transient high-degree AV block are at a substantial risk of sudden death.No clinical variable (such as age, syncope, angina, shortness of breath), or physical finding (such as S3 gallop, cardiomegaly, heart failure), or electrocardiographic finding (such as RBBB with LAD, RBBB with RAD, P-R interval prolongation), or electrophysiologic variable (such as A-H or H-V interval prolongation) is useful in predicting progression to complete heart block. All the above variables occur frequently in patients with BBB and yet the progression to CHB is relatively infrequent. One might single out His-Purkinje block with normal AV nodal conduction during atrial pacing as a possible marker for development of complete heart block. However, the opposite, namely a normal H-V interval, does not rule out progression to complete heart block.The data available on the use of pacing in patients with unexplained recurrent syncope or dizziness suggests that this approach is reasonable provided an effort has been made to exclude noncardiac cause for the symptoms. Some suggest that documentation of bradyarrhythmia or measurement of H-V interval is essential prior to institution of pacing. Further studies are needed to clarify this point.BBB complicating acute myocardial infarction places the individual at significant risk of developing congestive heart failure, with mortality usually secondary to myocardial failure or refractory ventricular arrhythmias. The pressence of high-degree AV block per se does appear to increase the mortality in patients without pump failure. Recent data suggest that immediate survival may be enhanced by prophylactic pacing in patients at high risk for abrupt complete heart block complicating acute myocardial infarction, but who do not manifest evidence of heart failure. The assumption that prophylactic pacing will improve survival of patients with bundle branch block and significant heart failure complicating acute myocardial infarction is purely speculative.Insufficient and conflicting data prevent a definitive statement regarding the usefulness of the P-R and H-V intervals as guidelines for the management of patients with recent-onset bundle branch block and acute myocardial infarction.Permanent pacing appears to benefit survivors of acute myocardial infarction complicated by BBB and transient high-degree AV block. However, the evidence is far from convincing.Little information is available on the influence of antiarrhythmic therapy on sudden death in patients with BBB. All currently used antiarrhythmic agents have a potentially high risk when administered to patients with BBB. Since there is no convincing prospective study as to the efficacy of drugs in preventing sudden death in patients with BBB, drug selection and its use in this group of patients remains at the discretion of the individual physician. It is based on the individual physician's experience with the drug in question and his perception of the benefit-to-risk ratio of the agent to be used. 相似文献
7.
Wambui Gathirua-Mwangi Andrea Cohee Will L. Tarver Andrew Marley Erika Biederman Timothy Stump Patrick Monahan Susan Rawl Celette Sugg Skinner Victoria L. Champion 《Women's health issues》2018,28(5):462-469
Background
Breast cancer is the second leading cause of cancer mortality, yet mammography screening rates remain less than optimal and differ by income levels. The purpose of this study was to compare factors predicting mammography adherence across income groups.Methods
Women 41 to 75 years of age (N = 1,681) with health insurance and with no mammogram in the last 15 months were enrolled to participate in an interventional study. Binary logistic regression was used to estimate multivariable-adjusted odds ratios (ORs) for demographic and health belief factors predicting mammography adherence for each income group: 1) low, less than $30,000, 2) middle, $30,000 to 75,000, and 3) high, greater than $75,000 per year.Results
Being in the contemplation stage (vs. precontemplation) of obtaining a mammogram predicted mammography adherence across all income groups and was the only predictor in the middle-income group (OR, 3.9; 95% CI, 2.61–5.89). Increase in age was associated with 5% increase (per year increase in age) in mammography adherence for low-income (OR, 1.05; 95% CI, 1.01–1.09) and high-income (OR, 1.05; 95% CI, 1.02–1.08) women. Having a doctor recommendation predicted mammography adherence only in low-income women (OR, 10.6; 95% CI, 2.33–48.26), whereas an increase in perceived barriers predicted mammography adherence only among high-income women (OR, 0.96; 95% CI, 0.94–0.99). In a post hoc analysis, high-income women reported difficulty in remembering appointments (53%) and lack of time to get a mammogram (24%) as key barriers.Conclusions
For all income groups, being in contemplation of obtaining a mammogram predicted mammography adherence; however, age predicted mammography adherence for low- and high-income groups, whereas doctor recommendation and perceived barriers were unique predictors for low- and high-income women, respectively. Health care providers should be aware of differences in factors and emphasize strategies that increase mammography adherence for each income group. 相似文献8.
D P Zipes E N Prystowsky J J Heger 《Journal of the American College of Cardiology》1984,3(4):1059-1071
Interest in amiodarone has increased because of its remarkable efficacy as an antiarrhythmic agent. The purpose of this report is to review what is known about the electrophysiologic actions, hemodynamic effects, pharmacokinetics, alterations of thyroid function, response to treatment of supraventricular and ventricular tachyarrhythmias and adverse effects of amiodarone. Understanding the actions of amiodarone and its metabolism will provide more intelligent use of the drug and minimize the development of side effects. The mechanism by which amiodarone suppresses cardiac arrhythmias is not known and may relate to prolongation of refractoriness in all cardiac tissues, suppression of automaticity in some fibers, minimal slowing of conduction in fast channel-dependent tissue, or to interactions with the autonomic nervous system, alterations in thyroid metabolism or other factors. Amiodarone exerts definite but fairly minor negative inotropic effects that may be offset by its vasodilator actions. Amiodarone has a reduced clearance rate, large volume of distribution, low bioavailability and a long half-life that may last 2 months in patients receiving short-term therapy. Therapeutic serum concentrations range between 1.0 and 3.5 micrograms/ml. The drug suppresses recurrences of cardiac tachyarrhythmias in a high percent of patients, in the range of 80% or more for most supraventricular tachycardias and in about 66% of patients with ventricular tachyarrhythmias, sometimes requiring addition of a second antiarrhythmic agent. Side effects, particularly when high doses are used, may limit amiodarone's usefulness and include skin, corneal, thyroid, pulmonary, neurologic, gastrointestinal and hepatic dysfunction. Aggravation of cardiac arrhythmias occurs but serious arrhythmias are caused in less than 5% of patients. Amiodarone affects the metabolism of many other drugs and care must be used to reduce doses of agents combined with amiodarone. 相似文献
9.
James R. Butler Joshua K. Kays Michael G. House Eugene P. Ceppa Attila Nakeeb Christian M. Schmidt Nicholas J. Zyromski 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2019,21(3):301-309
Background
Cirrhosis increases the risk of perioperative mortality in gastrointestinal surgery. Though cirrhosis is sometimes considered a contraindication to pancreatoduodenectomy (PD), few data are available in this patient population. The aim of the present study is to identify predictors of outcome in cirrhotic patients undergoing PD.Methods
Patients undergoing PD with biopsy-proved cirrhosis were evaluated. Primary endpoints were morbidity and mortality. Child score, MELD score, and radiographic evidence of portal hypertension (pHTN) were assessed for accuracy in preoperative risk stratification. A systematic review of the literature with meta-analysis was also performed to query morbidity and mortality of patients with cirrhosis reported to undergo PD.Results
Between 2005 and 2015, 36 cirrhotic patients underwent PD; three year follow-up was complete. Median Child score was 6 (range 5–10); median MELD score was 9 (range 7–18). Perioperative (90-day) mortality was 6/36. Median survival was 37 months (range 0.2–116). MELD ≥ 10 was associated with increased mortality (4/13 vs. 2/13, p = 0.004). Irrespective of Child or MELD score, those with pHTN had poor outcomes including significantly greater intraoperative blood loss, increased incidence of major complication, and length of stay. Postoperative mortality was significantly higher with pHTN (3/16 vs. 1/13, p = 0.012).Conclusion
Pancreatoduodenectomy may be considered in carefully selected cirrhotic patients. MELD ≥ 10 predicts increased risk of postoperative mortality. Specific attention should be afforded to patients with preoperative radiographic evidence of portal hypertension as this group experiences poor outcomes irrespective of MELD or Child score. 相似文献10.
The value of the exercise stress test in the evaluation of clinically healthy subjects and patients with coronary heart disease is not limited to the isolated interpretation of abnormalities of the S-T segment. Other measurable parameters which are of diagnostic and prognostic importance include: (1) a decrease in systolic blood pressure during exercise; (2) the appearance of complex ventricular arrhythmias of low exercise heart rates; (3) the appearance of inverted U waves during or after exercise; (4) the patient's maximal exercise capacity; and (5) new auscultatory findings postexercise. The reliability of the exercise test as a diagnostic tool is futher enhanced by proper patient selection and careful attention to exercise techniques. Subjects with labile ST-T wave changes during standing hyperventilation, fixed ST-T changes at rest, and intraventricular conduction defects are not ideal candidates for "diagnostic" stress testing and the examining physician must rely more heavily on nonelectrocardiographic findings. The criteria used to define an abnormal S-T response will vary according to the lead system used. However, in both symptomatic and asymptomatic subjects the appearance of marked degrees of S-T depression at low exercise heart rates significantly increases the probability of finding advanced coronary disease, particularly if the S-T depression is seen in multiple monitoring leads and is of prolonged duration postexercise. 相似文献