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Biomedical subjects

R M Carroll

Publications and source records attributed to R M Carroll.

11 recordsLinked to original sources

Angioscopy for intraoperative management of thromboembolectomy.

Our experience with angioscopy suggests that direct visualization of the arterial lumen during thromboembolectomy procedures would provide a more reliable method of assessing luminal morphologic characteristics than angiography alone. We inspected 32 grafts (seven aortobifemoral, 18 infrainguinal bypass, and seven dialysis access fistula grafts) in 32 patients. Thirty-one patients had thrombotic events and one patient had an acute embolus. Angioscopy following standard catheter thrombectomy revealed significant amounts of retained thrombus or neointima in all thrombectomies. Angioscopic information from 18 patients with an infrainguinal bypass graft led to graft revision in six cases and placement of a new graft in 10 cases. One graft limb was replaced in seven aortobifemoral grafts, and multiple repeated thrombectomies were employed to extract debris in the remaining six cases. Repeated graft thrombectomy was also beneficial in dialysis access fistulas. Angioscopy allowed us to omit the completion angiogram and led to an improved technical result. We conclude that angioscopy is useful during thromboembolectomy procedures.

Aged

Lipids and lipoproteins in a triethnic sample of 5- or 6-year-old Type A or Type B children.

The Type A behavior pattern (TABP) has been proposed as a risk factor for coronary heart disease (CHD). Several studies have indicated an association between Type A behavior and serum cholesterol levels. If the effects of TABP are mediated by conventional CHD risk factors, evidence for a causal relationship between TABP and CHD would be strengthened if associations were detected among the young. This paper addresses the following: (1) Do levels of serum lipids and lipoproteins among young children vary by ethnicity, gender, or TABP? (2) Can obtained differences be accounted for by possible confounding factors, such as SES or body composition? ANCOVA revealed no significant ethnic, gender, or TABP effects for total serum cholesterol or HDLc. Analyses of LDLc and triglycerides disclosed significant main effects for gender and for ethnicity. A Competition subscale by ethnicity interaction was the only effect to approach statistical significance for TABP. The strongest findings were a replication of differences in lipid and lipoprotein risk factors by ethnicity.

Black or African American

Comparison of contrast arteriography to arterial mapping with color-flow duplex imaging in the lower extremities.

Color flow duplex scanning was used to "map" the iliofemoral and femoral popliteal segments in 61 patients (84 extremities) undergoing evaluation for excimer laser angioplasty. Eight locations, iliac, common femoral, profunda femoris, proximal and distal superficial femoral artery, proximal and distal popliteal, and tibioperoneal trunk were scored as normal versus abnormal, greater than 50% stenosis, or occluded, and occlusions were measured in centimeters. Specificity, sensitivity, and accuracy were calculated with the arteriogram as the gold standard (83% and 96%, respectively, for normal vs abnormal, 87% and 99% for 50% stenosis, and 81% and 99% for occlusions). Color flow accurately identified the presence and extent of occlusions in 48 of 51 extremities (94%) when compared to arteriography plus operative findings, since arteriography alone tended to overestimate occlusion length. It is concluded that color flow Doppler alone may be used to screen patients with peripheral vascular disease to assess candidacy for endovascular procedures without antecedent arteriography, and that arteriography alone would exclude some patients from consideration by falsely overestimating occlusion lengths.

Angiography

Plasma lipoproteins in cortical versus lacunar infarction.

We investigated the relation of plasma lipids to the risk for ischemic stroke by comparing clinical and biochemical characteristics of survivors of cortical (n = 48) and lacunar (n = 36) brain infarction. By analysis of variance, no differences were observed in the concentrations of total cholesterol, triglycerides, low density lipoprotein cholesterol, very low density lipoprotein cholesterol, or apoproteins A1 and B. Patients with lacunar infarction, however, had higher concentrations of high density lipoprotein (HDL)-cholesterol than patients with cortical stroke. This HDL-cholesterol difference was due primarily to a strikingly low HDL-cholesterol content in white patients with cortical stroke. These data suggest that previously demonstrated differences in HDL-cholesterol concentrations between patients with ischemic stroke and control subjects without stroke may apply to patients with cortical but not lacunar infarction. Separation of cerebral infarction into subtypes based on mechanism may help clarify lipid-related risk factors in cerebrovascular disease.

Age Factors

Cardiac arrhythmias associated with treadmill claudication testing.

Eighty-one consecutive patients of an average age of 58 years with suspected lower limb arterial disease underwent standard 5-minute treadmill claudication testing. Prior to, during, and after testing the patients were monitored electrocardiographically. The number of electrocardiographic abnormalities seen in 81 patients undergoing study increased from 33 (40.6%) at rest to 49 (60.5%) with exercise. The commonest abnormalities encountered with exercise were the development and increased incidence of paroxysmal beats and ST-T wave changes which, in some instances, became life-threatening, aborting the test. Since the principal hazard for patients with claudication appears to derive from an increase propensity to cardiac mortality and morbidity, rather than from the consequences of impaired circulation to the limb, electrocardiographic monitoring during treadmill claudication testing, though little practiced, is strongly advised.

Adolescent

Comparison of the effects of the growth factor produced by Spirometra mansonoides and growth hormone in diabetic-hypophysectomized rats: lipid composition.

The effects of bovine growth hormone and the growth factor produced by plerocercoid larvae of the tapeworm, Spirometra mansonoides, on body growth and lipid composition in diabetic-hypophysectomized rats were compared. The diabetic-hypophysectomized control rats gradually lost weight throughout the experiment but both growth hormone and plerocercoids stimulated marked weight gains. Growth hormone treatment resulted in a loss of depot fat from the epididymal fat pads and caused a reduction of liver and serum cholesterol concentrations but had no effect on triglyceride concentrations of either liver or serum. However, plerocercoid infection resulted in increased weights of the epididymal fat pads and increased liver and serum triglyceride concentrations. Serum cholesterol was slightly increased but liver cholesterol was decreased in the plerocercoid-infected rats. Therefore, in the absence of pituitary hormones and insulin, these growth factors had similar effects on body growth but distinctly different effects on lipid metabolism.

Adipose Tissue

A lipogenic effect in intact male hamsters infected with plerocercoids of the tapeworm, Spirometra mansonoides.

Plerocercoids of the tapeworm, Spirometra mansonoides, produce a potent growth stimulating substance which is active in several species of mammals. While most of the actions of the plerocercoid growth factor (PGF) are similar to those of growth hormone (GH), lipid metabolism is one area where their actions are not alike. This report demonstrates that plerocercoid infection not only stimulates growth of intact male hamsters but is lipogenic as well. The lipogenic effects of plerocercoid infection were demonstrated by increases in epididymal fat pad weights, serum triglycerides, cholesterol, and total lipid. The livers of the plerocercoid-infected hamsters also had more cholesterol and more lipid phosphorus than controls. Incorporation studies using [2-14C]acetate showed that infected hamsters incorporated significantly higher levels of the radionuclide in their livers and serum after 1 hr than the controls. The lipogenic effect of plerocercoid infection is distinctly unlike the reported lipolytic action of GH and the lack of any stimulation of [2-14C]acetate incorporation into the epididymal fat pads is unlike the reported acute actions of insulin as well.

Acetates

Left ventricular function during aortic surgery.

Fourteen patients undergoing surgery for aneurysm or occlusive disease of the abdominal aorta were studied. Thirteen patients had a history of hypertension or myocardial infarction; two patients had chronic obstructive pulmonary disease. Tachycardia, hypertension, and elevated pulmonary artery occluded. (PAo) pressure occurred in response to laryngoscopy and intubation in two patients; elevation of PAo pressure in response to aortic cross-clamping occurred in two patients. In three of these four patients, electrocardiographic evidence of myocardial ischemia appeared. These events are important in a consideration of the occurence of myocardial infarction in patients undergoing abdominal aortic surgery. Satisfactory treatment of myocardial ischemia has been accomplished with the use of propranolol hydrochloride and sodium nitroprusside.

Aged