PubMed Health⌕ Search

Biomedical subjects

T P Murphy

Publications and source records attributed to T P Murphy.

At least 73 records · Page 4Linked to original sources

An apparent rachitogenic effect of excessive vitamin E intakes in the chick.

Three replicates (pens of 10 birds each) of a 2 X 2 factorial design experiment (25 and 10,000 IU vitamin E/kg diet on 25 and 500 IU vitamin D/kg diet) were utilized in order to assess effects of excessive intakes of vitamin E on calcium metabolism in the growing chick. A one-week equilibration period was followed by a two-week experimental period. Excessive vitamin E supplementation resulted in reduced calcium and phosphorus in blood plasma, in dry fat-free bone, and in bone ash, calcium, and phosphorus. Inadequate vitamin D supplementation reduced total feed consumption, terminal body weight, plasma calcium, dry fat-free-bone, bone ash, bone calcium, and bone phosphorus. Significant vitamin E X vitamin D interactions were noted for plasma calcium, dry bone, and bone ash, excessive vitamin E apparently interfering with vitamin D utilization.

Animal Feed↗

Iatrogenic arterial dissection: treatment by percutaneous transluminal angioplasty.

Iatrogenic arterial dissection may require intervention, depending on the severity of resulting stenosis and the degree of symptoms. We present 5 cases of iatrogenic arterial dissection: 1 with dissection of the lower abdominal aorta, common iliac artery, and external iliac artery, and 3 with external iliac artery dissections, all managed with percutaneous transfemoral transluminal angioplasty; and 1 with dissection of the superior mesenteric artery with angioplasty performed by the translumbar approach. Four of the 5 patients had no additional therapy; 1 patient eventually underwent surgery for an asymptomatic residual pseudoaneurysm seen on abdominal computed tomography. Angiographic follow-up in 2 patients demonstrated persistent improvement in stenosis, 1 at 2 weeks after angioplasty, and the other, 6 weeks following angioplasty. None of the 5 patients required further therapy for recurrence of symptoms on clinical follow-up obtained up to 1 year after angioplasty. Though the incidence of recurrent arterial stenosis following angioplasty for dissection may be greater than that incurred after intravascular stent placement or surgery, angioplasty may be effective, and has the advantage of being less expensive than both of these treatment modalities, and more widely available and applicable than intravascular stents.

Adult↗

Use of a puncture needle for recanalization of an occluded right subclavian vein.

We report a patient in whom we used a puncture needle to initiate percutaneous recanalization of a chronic occlusion of the junction between the right subclavian vein and the right brachiocephalic vein. Under fluoroscopic guidance, an 18-gauge needle was used to puncture the right subclavian vein. When contrast material injected through the needle confirmed intravascular location, the needle was advanced until it deflected and perforated an occlusion balloon target positioned within the right brachiocephalic vein. This technique may be useful in patients with central venous occlusions that are refractory to traversal using traditional catheter and guidewire techniques.

Aged↗

Percutaneous revascularization of complex iliac artery stenoses and occlusions with use of Wallstents: three-year experience.

PURPOSE: To assess the outcome of percutaneous placement of Wallstents for treatment of hemodynamically significant diffuse stenoses (> 3 cm in length), chronic occlusions, failed angioplasty procedures, and flow-limiting dissection in the iliac arteries. MATERIALS AND METHODS: Lesions in 94 iliac limbs were treated in 66 patients. Indications for stent placement included claudication in 49 limbs and limb-threatening ischemia in 45. Forty-two limbs were treated for diffuse disease, 39 for chronic occlusion, nine for failed angioplasty, and four for flow-limiting dissection. RESULTS: Technical success was achieved in 86 of 94 limbs (91%), with major complications in 9% of patients. One death occurred within 30 days (not procedure-related). Ankle-brachial indexes improved from 0.51 +/- 0.24 to 0.76 +/- 0.22 (P < .001). Eighty-five percent demonstrated improvement under Rutherford criteria. Follow-up was obtained up to 38 months (mean, 14 months +/- 8). Cumulative primary patency rates were 78% at 1 year and 53% at 2 and 3 years (standard error 10%). Secondary patency rates were 86% at 1 year and 82% up to 32 months (standard error > 10% after 32 months). No significant decrease in mean ankle-brachial index was observed during follow up. No difference in primary patency was observed based on lesion type, symptom severity, lesion location, or runoff status. The limb salvage rate for patients with limb-threatening ischemia was 98% at a mean follow-up of 14 months +/- 7. CONCLUSIONS: Technical success and complication rates for percutaneous iliac artery revascularization with use of Wallstents are favorable, symptoms improved in the majority of patients, and excellent secondary patency can be achieved. With use of Wallstents, most patients with iliac artery insufficiency as a result of long-segment disease or chronic occlusions can be treated percutaneously.

Arterial Occlusive Diseases↗

Local thrombolytic therapy as part of a multidisciplinary approach to acute axillosubclavian vein thrombosis (Paget-Schroetter syndrome).

PURPOSE: To evaluate the efficacy of thrombolytic therapy in the treatment of acute axillosubclavian vein thrombosis in patients with Paget-Schroetter syndrome. MATERIALS AND METHODS: A 4.5-year, retrospective study of all patients with "effort" thrombosis of the axillosubclavian vein was performed. RESULTS: Six men and eight women (age range, 18-56 years; mean, 34 years) presented with acute axillosubclavian vein thrombosis. Twenty thrombotic events occurred in the 14 patients and were treated with urokinase only (14 of 20) or urokinase combined with percutaneous transluminal angioplasty (PTA) (six of 20), Nine of the 14 treatments with urokinase only (64%) resulted in complete lysis of thrombus, whereas four treatments (29%) resulted in restoration of flow with some residual stenosis, yielding an immediate patency rate of 93%. Eight of the 14 patients remained asymptomatic after thrombolytic therapy (urokinase or urokinase and PTA) alone (n = 4), or in combination with a first rib resection (n = 4) at a mean follow-up of 24 months (range, 1-36 months). CONCLUSIONS: Thrombolytic therapy appears to be a safe and efficacious method of establishing immediate patency of the axillosubclavian vein and may be helpful in establishing a symptom-free result in patients with Paget-Schroetter syndrome. Rib resection and repeated thrombolytic therapy are frequently necessary to complete treatment.

Acute Disease↗

Long-term follow-up after TIPS: use of Doppler velocity criteria for detecting elevation of the portosystemic gradient.

PURPOSE: To evaluate the performance of Doppler ultrasound as a screening test for detecting elevated portosystemic gradients in failing transjugular intrahepatic portosystemic shunts (TIPS). MATERIALS AND METHODS: Twenty-seven of 61 patients who underwent TIPS creation between November 1991 and March 1996 were studied. At routine intervals, angle-corrected velocity measurements of portal venous and intrashunt blood flow (at the portal venous, middle, and hepatic venous levels of the shunt) were obtained. These were compared with portal hemodynamics for diagnostic accuracy in predicting clinically significant elevation of the portosystemic gradient. Venographic and manometric correlations were obtained on all patients available for follow-up and were not limited to those with symptoms or "abnormal" Doppler studies. Receiver-operating characteristic (ROC) curves were done. Linear regression was done to study correlation of shunt velocities with portal pressure, and logistic regression was done to predict shunt stenosis with use of shunt velocities. RESULTS: The most accurate location for shunt velocity measurement was the main portal vein, but this had an area under the ROC curve of only 0.70. Accuracy of any velocity threshold (including maximum shunt velocity) was no greater than 70%. Maximum shunt velocity of less than 60 cm/sec was 93% specific for detecting shunt restenosis, but only 25% sensitive, for an overall accuracy of 64%. High sensitivity (90%) could only be achieved with poor specificity (< 33%). Linear regression revealed poor correlation between shunt or portal vein velocity measurements and portal pressure (/r/ < 0.23 for all). CONCLUSIONS: Intrashunt and portal venous Doppler velocities alone do not accurately predict elevation of the portosystemic gradient on long-term follow-up after TIPS.

Adult↗

Aortoiliac stent placement in patients treated for intermittent claudication.

PURPOSE: To assess the results of iliac artery stent placement for the treatment of patients with intermittent claudication. MATERIALS AND METHODS: Lesions in 90 iliac arteries were treated in 65 patients with 111 Wallstents and 21 Palmaz stents. Stents were placed for symptoms of intermittent claudication classified as grade I, categories 1-3 by the SVS/ISCVS/SCVIR reporting standards. Sixty-two stenosed arteries and 28 chronically occluded arteries were treated. Patients were followed for up to 57.1 months (mean, 17.4 months +/- 14.9). RESULTS: Technical success was achieved in 87 of 90 iliac limbs (97%), with major complications in seven of 65 patients (11%). The 30-day mortality was zero. Mean pressure gradients across stenoses improved from 14.7 mm Hg +/- 9.8 to 1.4 mm Hg +/- 1.4 (P < .001). Ankle-brachial indices improved from 0.62 +/- 0.21 to 0.90 +/- 0.18 (P < .001). With use of the Rutherford criteria, 84% demonstrated +2 or +3 improvement. The cumulative patency rates were 77%, 71%, 62%, and 62% at 1, 2, 3, and 4 years (standard error [SE] < 10%). Continued clinical and noninvasive test benefit was present in 80%, 80%, 73%, and 73% at 1, 2, 3, and 4 years, respectively (SE < 10%). CONCLUSIONS: Significant hemodynamic improvement can be achieved by percutaneous stent placement, with excellent clinical results. Observed mortality in this series was zero, but major complications, requiring modification of the treatment plan, were seen in 11% of patients. Clinical results were better than suggested using current accepting reporting standards for "patency."

Aorta, Abdominal↗

Stent placement for treatment of mesenteric artery stenoses or occlusions.

PURPOSE: To evaluate stent placement in the treatment of mesenteric ischemia. PATIENTS AND METHODS: Twelve patients (eight women, four men; mean age, 63 years) with chronic mesenteric ischemia underwent stent placement for stenoses or occlusions during a 5.5-year period. Nine patients with 10 stenoses (three celiac arteries, seven superior mesenteric arteries) and three patients with three chronic occlusions (two superior mesenteric arteries, one aortosuperior mesenteric artery bypass graft) were treated. RESULTS: Initial technical success was achieved in 11 of the 12 patients (92%), including all three patients with chronic occlusions. There were no technical complications. There was one postprocedural death (<30 days) due to bowel ischemia and infarction, despite a technically successful procedure. Clinical follow-up was available in all 12 patients, with a mean follow-up of 15.7 months (range, 0-38.5 months). Primary and primary-assisted patency up to 18 months was 74% (standard error [SE], 13%) and 83% (SE, 11%), respectively. Secondary patency was 83% (SE, 11%) at 3 years. All three patients (100%) with chronic occlusions had relief of clinical signs and symptoms at a mean follow-up of 22 months (range, 13-38.5 months). CONCLUSIONS: Stent placement is safe and clinically effective as an adjunctive therapy to angioplasty or as a primary method of treatment for chronic mesenteric ischemia in patients with focal visceral artery stenoses or occlusions.

Aged↗