Understanding the recent growth in Medicare physician expenditures

This study employs several large Health Care Financing Administration data sets for 1983 and 1985 to examine the recent growth in Medicare physician services. The study concludes that the recent growth (approximately 15% in real terms between 1983 and 1985) has been more rapid in areas with higher incomes per capita and suggests that this may be related to faster adoption and diffusion of new medical technologies in these areas. The volume of physician services had grown considerably faster for those specialists who utilize newer procedures and technologies than for those who do not. The study also provides evidence that the sharp increase in assignment rates in recent years because of the introduction of the physician participation program also contributed to the growth in physician services during this period. Medicare's prospective payment system, which controlled hospital payments and encouraged hospitals to become more efficient, had at most a small positive impact on the growth in Part B spending. Finally, the freeze on physician's fees did not seem to have had a major impact on the volume of physician services.     

Troponin T levels in baboons with pig heterotopic heart transplants.

Troponin T levels have been monitored in baboons (n = 8) undergoing pig heterotopic heart transplantation, and correlated with a decrease in graft contractions and graft survival. Pig heart graft survival was from 12 to 139 days (mean 45, median 33), and graft failure was associated with predominant thrombotic microangiopathy and ischemia, with focal hemorrhage, and edema. An increase in troponin T levels 5 to 6 days before graft failure correlated closely with diminished graft contractions. An increase in troponin T was a reliable indicator that graft dysfunction was occurring.     

Resection of the inferior vena cava and tumor of the excretory duct: diagnostic and prognostic problems

The authors present a case of transitional cell carcinoma of the renal pelvis with inferior vena cava involvement. Two types of vena cava involvement are discussed: thrombus or nodes. The CT scan appears to be the best examination to preoperatively diagnose the type of invasion in order to be able to select the optimal treatment. However, these two types of involvement have a poor prognosis and surgery abstention may be justified. Chemotherapy may be useful in these cases.     

Severity of asymptomatic carotid stenosis and risk of ipsilateral hemispheric ischaemic events: results from the ACSRS study.

OBJECTIVES: This study determines the risk of ipsilateral ischaemic neurological events in relation to the degree of asymptomatic carotid stenosis and other risk factors. METHODS: Patients (n=1115) with asymptomatic internal carotid artery (ICA) stenosis greater than 50% in relation to the bulb diameter were followed up for a period of 6-84 (mean 37.1) months. Stenosis was graded using duplex, and clinical and biochemical risk factors were recorded. RESULTS: The relationship between ICA stenosis and event rate is linear when stenosis is expressed by the ECST method, but S-shaped if expressed by the NASCET method. In addition to the ECST grade of stenosis (RR 1.6; 95% CI 1.21-2.15), history of contralateral TIAs (RR 3.0; 95% CI 1.90-4.73) and creatinine in excess of 85 micromol/L (RR 2.1; 95% CI 1.23-3.65) were independent risk predictors. The combination of these three risk factors can identify a high-risk group (7.3% annual event rate and 4.3% annual stroke rate) and a low risk group (2.3% annual event rate and 0.7% annual stroke rate). CONCLUSIONS: Linearity between ECST per cent stenosis and risk makes this method for grading stenosis more amenable to risk prediction without any transformation not only in clinical practice but also when multivariable analysis is to be used. Identification of additional risk factors provides a new approach to risk stratification and should help refine the indications for carotid endarterectomy.     

Left ventricular aneurysm: a new surgical approach

Since 1984, we have used a circular patch to reconstruct the left ventricle ("endoventricular circular plasty") in order to maintain a more physiologic cavity. This technique has three theoretical advantages over standard linear closure of the left ventricle (LV). First, it allows exclusion of the septal akinetic segment of the LV. Secondly, circular reorganization of the remaining LV muscle avoids the restraint caused by the linear suture closure and achieves a more physiologic LV cavity. Thirdly, circular plasty using the patch allows a complete resection of aneurysmal segments including resection of extensive subendocardial scar tissue, when appropriate, without critically compromising the cavity size. The technique involves the following steps: --Resection of dyskinetic or akinetic LV free wall and thrombectomy when indicated. --A dacron patch lined with pericardium is secured at the junction of the endocardial muscle and scarred tissue, thereby excluding non contractile portions of the LV and septum. --Myocardial revascularization is performed as indicated with particular attention paid to revascularizing the proximal left anterior descending segment. The group of patients forming this study includes 130 cases of LV reconstruction since 1984. The three main indications for surgery were angina (40%), cardiac failure (35%), arrhythmias (10%). There have been 8 hospital deaths, 4 late mortalities related to recurrence of cardiac failure in this group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of gonadotrophin-releasing hormone agonists on human ovarian steroid secretion in vivo and in vitro-results of a prospective, randomized in-vitro fertilization study

The aim of this prospective randomized study was to compare the effects of two gonadotrophin-releasing hormone (GnRH) agonists, buserelin and triptorelin, on human ovarian follicular steroidogenesis, oocyte fertilization and IVF treatment outcome. Ovulatory, healthy women undergoing IVF were treated either with human menopausal gonadotrophin (HMG) alone or with HMG and one of the two GnRH agonists. Serum and follicular fluid hormonal concentrations and cultures of luteinizing granulosa cells obtained during follicular aspiration were analysed. GnRH agonist treatment significantly affected steroidogenesis both in serum and follicular fluid. In follicular fluid, progesterone and oestradiol concentrations were significantly elevated while testosterone concentrations were significantly lower in the triptorelin group. The ratios of testosterone/progesterone, oestradiol/progesterone but not oestradiol/testosterone concentrations were significantly affected by GnRH agonist administration. Similarly, the steroidogenic activity of luteinizing granulosa cells in vitro was significantly decreased in women treated with GnRH agonists. Women treated with GnRH agonists had significantly more fertilized oocytes and cleaving embryos. The results indicate a marked effect of GnRH agonists on the pattern of ovarian follicular steroidogenesis that cannot be explained solely by changes in gonadotrophin concentrations.     

Up-regulation of ICAM-1, CD11a/CD18 and CD11c/CD18 on human THP-1 monocytes stimulated by Streptococcus suis serotype 2

Streptococcus suis serotype 2 is known to be a major pathogen of swine, causing mainly meningitis. It is also a zoonotic agent leading predominantly to meningitis in humans working in close contact with pigs. In this study, we investigated the ability of S. suis to up-regulate the expression of adhesion molecules involved in inflammation, using an enzyme-linked immunosorbent assay. S. suis serotype 2 stimulated the up-regulation of the expression of intercellular adhesion molecule-1 (ICAM-1, CD54), CD11a/CD18 and CD11c/CD18 on human THP-1 monocytes, but did not change that of ICAM-1, vascular cell adhesion molecule-1 (VCAM-1, CD106) and E-selectin (CD62E) on human endothelial cells. The up-regulation of adhesion molecules was time- and bacterial concentration-dependent, and cell wall components were largely responsible for such stimulation. To a lesser extent, purified haemolysin of S. suis also stimulated adhesion molecule expression. Stimulation of monocytes with strains of different origin showed that there was no clear tendency for human strains to induce a higher expression of adhesion molecules than strains from diseased pigs. Finally, monocytes stimulated with S. suis also showed an increase in adherence to endothelial cells. Hence, S. suis is capable of up-regulating important adhesion molecules involved in inflammation, which may result in an increased leucocyte recruitment into sites of infection, thus providing a possible mechanism for some of the inflammatory features of meningitis caused by this pathogen.     

Acute inflammatory reaction after myocardial ischemic injury and reperfusion. Development and use of a neutrophil-specific antibody.

Reperfusion of the infarcted canine myocardium after 1 hour of ischemia is associated with an acute inflammatory infiltrate at the border of the infarct. In this paper, we demonstrate that early margination and emigration of neutrophils originate in thin-walled (approximately 5 micrometers) venous cisterns that average 200 micrometers in length and vary from 10 to 70 micrometers in width and show strong constitutive expression of both ICAM-1 and P-selectin; this class of vessels (venous cisterns) appears to be a unique feature in heart. A monoclonal antibody (SG8H6) with specificity for canine neutrophils was developed that allowed much more sensitive immunohistochemical detection of neutrophils in tissue and allowed us to follow tissue infiltration with time. Samples from 1 hour of reperfusion revealed dense margination and substantial emigration of neutrophils associated with the venous cisterns and collecting venules. By 2 hours, there was intense local emigration to the extravascular space between cardiac myocytes. By 3 hours, the infiltrate extended deeper into the infarct, and there was a continuous border zone of neutrophil infiltration that overlapped a region where intact cardiac myocytes strongly expressed ICAM-1 mRNA and extended into the necrotic tissue. At later times, neutrophil migration into infarcted tissue continued to progress. Neutrophil transmigration into reperfused myocardium is more extensive than previously described, and its extravascular distribution during early reperfusion is primarily in the viable border zone of the myocardium where myocyte ICAM-1 mRNA is found. These data are compatible with the hypothesis that extravascular neutrophils may participate in reperfusion injury.