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T S Riles

Publications and source records attributed to T S Riles.

At least 37 records · Page 2Linked to original sources
PubMed1997

A multidisciplinary approach to the treatment of Paget-Schroetter syndrome.

To assess the results of thrombolytic therapy and surgical decompression of the thoracic outlet in the management of spontaneous axillary vein thrombosis (AVT), the records of 38 patients at New York University Medical Center (NYUMC) with AVT were reviewed. Excluded from this report were 20 patients who had AVT secondary to an underlying medical condition, a subclavian catheter, or a failed dialysis access graft. Of the 18 remaining patients with no underlying medical condition, all were found to have effort-related axillo-subclavian thrombosis, Paget-Schroetter syndrome. Urokinase was used for thrombolysis in 17 of the 18 patients, (94.4%) with complete lysis in 14 (82.4%). The remaining patient received anticoagulation only following a favorable response to an initial heparin infusion. Of the patients achieving complete thrombolysis, all but one received urokinase within 8 days of the onset of symptoms. Clot lysis revealed axillary vein compression secondary to a thoracic outlet syndrome in 11 patients, and these underwent staged transaxillary thoracic outlet decompression by first rib resection. All 17 patients have been followed for a mean of 21 months, and none receiving lytic therapy have reoccluded. Review of these data confirms earlier reports showing that with early diagnosis, thrombolysis and, if indicated, thoracic outlet decompression, patients with spontaneous AVT can expect excellent clinical results with a good long-term prognosis.

Anticoagulants↗
PubMed1997

A unique approach in the management of vena caval thrombosis in a patient with Klippel-Trénaunay syndrome.

Vena caval thrombosis has posed a surgical therapeutic challenge for many years. Historically, spiral vein grafts and synthetic materials used as prostheses have had variable results. The use of the stent may serve as a more promising alternative when used in the capacity to relieve caval obstruction. A case is reported in which a young woman with Klippel-Trénaunay syndrome has exercise intolerance and associated hypotensive cardiovascular collapse caused by inferior vena caval thrombosis. Recanalization of her inferior vena cava was successfully achieved and subsequently maintained through the placement of two Wallstents across the lesion. Although most venous stenting procedures have thus far been used in the treatment of venous obstruction caused by malignancy, inferior vena cava stenting in this patient with inferior vena caval thrombosis and Klippel-Trénaunay syndrome suggests that venous stenting might offer an alternative therapeutic modality in treating a broader spectrum of occlusive venous disease.

Adult↗
PubMed1997

Natural history and management of the asymptomatic, moderately stenotic internal carotid artery.

PURPOSE: Although it has been widely accepted as the evidence supporting prophylactic carotid endarterectomy, aspects of the Asymptomatic Carotid Atherosclerosis Study have left unease among clinicians who must decide which individuals without symptoms should undergo surgery. Additional confusion has been created by the fact that the several large randomized trials investigating the efficacy of carotid endarterectomy have classified and analyzed different categories of carotid stenosis. In an effort to provide more information on the natural history of asymptomatic, moderate carotid artery stenosis (50% to 79%), we have reviewed data on approximately 500 arteries. METHODS: Records of our vascular laboratory from 1990 to 1992 were reviewed. We identified 425 patients with asymptomatic, moderate carotid artery stenosis; 71 patients had bilateral stenoses in this category, resulting in 496 arteries for study. RESULTS: The mean length of follow-up was 38 +/- 18 months. New ipsilateral strokes occurred in 16 (3.8%) patients. New ipsilateral transient ischemic attacks occurred in 25 (5.9%) patients. Documented progression of stenosis occurred in 48 (17%) of the 282 arteries for which a repeat duplex examination was available. Arteries that progressed to > 80% stenosis were significantly more likely to have caused strokes than those that remained in the 50% to 79% range (10.4% vs 2.1%, p < 0.02). Conversely, arteries that remained stable in the degree of stenosis were significantly more likely to have remained asymptomatic than those that progressed (92.7% vs 62.5%, p < 0.001). With life-table analysis the estimated cumulative ipsilateral stroke rate was 0.85% at 1 year, 3.6% at 3 years, and 5.4% at 5 years. The respective estimated cumulative transient ischemic attack rates were 1.9%, 5.5%, and 6.3%. The respective estimated cumulative rates for progression of stenosis were 4.9%, 16.7%, and 26.5%. Life-table comparison of ipsilateral stroke revealed a significantly higher cumulative rate among arteries that progressed in the degree of stenosis than among those that remained stable (p < 0.001). CONCLUSIONS: Based on the low rate of permanent neurologic events in these cases, prophylactic carotid endarterectomy for the asymptomatic, moderately stenotic internal carotid artery cannot currently be recommended. The only factor that appears to predict increased risk for future stroke is progression of stenosis. Careful follow-up with serial repeat duplex examinations must be performed in these patients. Until there are widely accepted duplex parameters that can provide all clinicians with accurate identification of arteries with narrowing corresponding to 60% stenosis as defined by the Asymptomatic Carotid Atherosclerosis Study, all surgeons will need to be aware of specifically how their noninvasive laboratories are deriving their results. For the many laboratories that continue to use the University of Washington criteria, 80% should remain the level above which prophylactic carotid endarterectomy is warranted.

Aged↗
PubMed1997

Comparison of lumbar and thoracic epidural narcotics for postoperative analgesia in patients undergoing abdominal aortic aneurysm repair.

OBJECTIVE: To determine whether there is an advantage of thoracic over lumbar epidural narcotics for postoperative analgesia in patients undergoing abdominal aortic aneurysm repair. DESIGN: A prospective randomized study. SETTING: Subjects were inpatients at an academic medical center. PARTICIPANTS: Fifty-two patients scheduled for elective abdominal aortic aneurysm repair. INTERVENTIONS: Subjects were randomly assigned to receive lumbar or thoracic epidural narcotics. Group 1 (n = 26) had lumbar, and group 2 (n = 26) had thoracic epidural catheters placed preoperatively. All patients were monitored with pulmonary artery catheters and arterial catheters, and had general endotracheal anesthesia, in addition to epidural anesthesia with 2% lidocaine. All patients received 5 mg of epidural morphine after intubation. Pain scores were monitored hourly for 36 hours using a visual analog scale, and additional narcotics were given, depending on the level of pain. Complications caused by epidural narcotics were recorded. RESULTS: There was no difference between groups as to the daily dose of narcotics or the time between narcotic doses. Hourly pain scores showed significant differences during hours 6, 7, 8, 20, 34, and 36, with pain scores being lower in group 1. There was no difference in the rate of complications between the groups. CONCLUSION: There is no advantage of thoracic over lumbar epidural analgesia using morphine in patients undergoing abdominal aortic aneurysm repair.

Aged↗
PubMed1996

Perioperative morbidity and mortality in combined vs. staged approaches to carotid and coronary revascularization.

Between 1986 and 1994 we identified 57 patients who underwent carotid endarterectomy (CEA) and coronary artery bypass grafting (CABG) during the same hospitalization. Simultaneous CABG and CEA was performed in 28 patients (mean age 70.5 years, 58% male). Indications for CABG in these patients were myocardial infarction in two crescendo angina in 19, congestive heart failure in two and left main or triple-vessel coronary artery disease noted during carotid preoperative evaluation in five. Indications for CEA were transient ischemic attack (TIA) in 12, crescendo TIA in six, cerebrovascular accident (CVA) in five, and asymptomatic stenosis in five. There were no postoperative myocardial infarctions or perioperative deaths. Two patients developed atrial fibrillation, and four patients had CVAs (two were ipsilateral to the side of CEA). Twenty-nine patients underwent staged procedures (i.e., not performed concomitantly but during the same hospitalization). Indications for CABG and CEA were comparable to those in the group undergoing simultaneous procedures. In 17 patients CEA was performed before CABG. There was a single CVA, the result of an intracerebral hemorrhage. Five of the 17 patients had a myocardial infarction and two died; one patient had first-degree heart block requiring a pacemaker. Four additional patients developed atrial fibrillation, one of whom required cardioversion. The remaining 12 patients had CABG followed by CEA. There were no CVAs, myocardial infarctions, arrhythmias, or deaths in this subgroup. These data demonstrate that the performance of simultaneous CABG and CEA procedures is associated with increased neurologic morbidity (14.3%), both ipsilateral and contralateral to the side of carotid surgery in contrast to staged CABG and CEA (3.4%). In addition, when staged carotid surgery preceded coronary revascularization in those with severe coronary artery disease, the combined cardiac complication and mortality rate was significantly higher than when coronary revascularization preceded CEA. This evidence suggests that when CABG and CEA must be performed during the same hospitalization, the procedures should be staged with CABG preceding CEA.

Aged↗
PubMed1996

The surgical management of carotid artery stenosis in patients with previous neck irradiation.

BACKGROUND: A history of therapeutic irradiation to the neck complicates the management of carotid artery occlusive disease. Serious surgical concerns are raised regarding alternative incisions, difficult dissections, and adequate wound closure. Pathology may be typical atherosclerotic occlusive disease or radiation-induced arteritis. In order to establish guidelines for the treatment of these patients, we have reviewed our operative experience. PATIENTS AND METHODS: A review of our operative experience over the past 15 years revealed 10 patients with a history of prior irradiation to the neck who underwent 14 carotid operations. RESULTS: The indications for radiation included laryngeal carcinoma and lymphoma. Five patients had undergone previous radical neck dissections, and four patients had permanent tracheostomies. The surgical indications were asymptomatic high-grade stenosis in 7 cases, transient ischemic attack in 4 cases, stroke in 2 cases, and a pseudoaneurysm in 1 case. Conventional carotid endarterectomy with patch angioplasty was used in 10 of the 14 operations. In the remaining four operations, saphenous vein interposition grafting was utilized to replace the diseased segment of carotid artery secondary to a panarteritis. Wound closure required dermal grafting in two of five cases where surgery was performed ipsilateral to a prior radical neck dissection. One perioperative cerebral infarction occurred; there were no other neurologic or non-neurologic complications. All patients are doing well in one- to five-year follow-up, with serial postoperative duplex scans demonstrating no signs of recurrent stenosis. CONCLUSIONS: Patients with a history of irradiation to the neck should be screened for the presence of carotid disease. Carotid occlusive disease should be treated surgically in these patients with the usual indications. Intraoperative surgical management is similar to that of non-irradiated patients. Concerns about difficulty in achieving an adequate endarterectomy plane and about problems with wound closure have generally been unfounded.

Aged↗
PubMed1996

Deep venous thrombosis with pulmonary embolus after selective embolization of an internal iliac artery aneurysm.

A 69-year-old man with an isolated right internal iliac artery aneurysm measuring 5.6 cm in diameter was treated with percutaneous embolization inducing thrombosis of the aneurysm. Four months later, he was seen with thrombosis of the right common iliac vein and pulmonary embolus. He subsequently underwent ligation of the aneurysm and repair of the right common iliac artery. Computed tomographic and operative findings suggested that the iliac vein thrombosis was the result of direct compression by the aneurysm itself, as well as perianeurysmal inflammation that encased the right common iliac vein. This report summarizes this case and presents a new potential long-term complication after successful selective embolization of an internal iliac artery aneurysm.

Aged↗
PubMed1996

A comparison of regional and general anesthesia in patients undergoing carotid endarterectomy.

PURPOSE: The optimal anesthetic for use during carotid endarterectomy is controversial. Advocates of regional anesthesia suggest that it may reduce the incidence of perioperative complications in addition to decreasing operative time and hospital costs. To determine whether the anesthetic method correlated with the outcome of the operation, a retrospective review of 3975 carotid operations performed over a 32-year period was performed. METHODS: The records of all patients who underwent carotid endarterectomy at our institution from 1962 to 1994 were retrospectively reviewed. Operations performed with the patient under regional anesthesia were compared with those performed with the patient under general anesthesia with respect to preoperative risk factors and perioperative complications. RESULTS: Regional anesthesia was used in 3382 operations (85.1%). There were no significant differences in the age, gender ratio, or the rates of concomitant medical illness between the two patient populations. The frequency of perioperative stroke in the series was 2.2%; that of myocardial infarction, 1.7%; and that of perioperative death, 1.5%. There were no statistically significant differences in the frequency of perioperative stroke, myocardial infarction, or death on the basis of anesthetic technique. A trend toward higher frequencies of perioperative stroke (3.2% vs 2.0%) and perioperative death (2.0% vs 1.4%) in the general anesthesia group was noted. In examining operative indications, however, there was a significant increase in the percentage of patients receiving general anesthesia who had sustained preoperative strokes when compared with the regional anesthesia patients (36.1% vs 26.4%; p < 0.01). There was also a statistically significant higher frequency of contralateral total occlusion in the general anesthesia group (21.8% vs 15.4%; p = 0.001). The trend toward increased perioperative strokes in the general anesthesia group may be explicable either by the above differences in the patient populations or by actual differences based on anesthetic technique that favor regional anesthesia. CONCLUSIONS: In a retrospective review of a large series of carotid operations, regional anesthesia was shown to be applicable to the vast majority of patients with good clinical outcome. Although the advantages over general anesthesia are perhaps small, the versatility and safety of the technique is sufficient reason for vascular surgeons to include it in their armamentarium of surgical skills. Considering that carotid endarterectomy is a procedure in which complication rates are exceedingly low, a rigidly controlled, prospective randomized trial may be required to accurately assess these differences.

Aged↗
PubMed1995

A comparative study of saphenous vein, internal jugular vein, and knitted Dacron patches for carotid artery endarterectomy.

To determine whether the choice of material used for patch closure following carotid artery endarterectomy (CAE) affected the immediate operative results, the early follow-up results, or the incidence of early restenosis, a retrospective study of 275 consecutive carotid endarterectomies by two vascular surgeons was performed. Among 275 primary CAEs performed between July 1991 and August 1993, 159 (57.8%) were closed with saphenous vein (SV), 25 (9.1%) with double-thickness internal jugular vein (JV), and 91 (33.1%) with knitted Dacron (KD). Primary closure was not used in any of the arteries in this series. The overall perioperative mortality rate was 1.1% and the rate of major and minor morbidity was 4.4% There were four (1.5%) perioperative strokes: two (1.3%) in the SV group, one (4.0%) in the JV group, and one (1.1%) in the KD group. Two-hundred fifty-eight (93.8%) of the 275 endarterectomies were followed postoperatively for 2 to 35 months (mean 14.4). Two-hundred nineteen (79.6%) were evaluated using duplex scans during follow-up with a mean interval of 13.7 months. Of the arteries studied, four (3.6%) in the SV group, none in the JV group, and six (8.4%) in the KD group demonstrated restenosis of > 50% at the time of follow-up (NS). In addition, one (0.9%) artery in the SV group, one (5.6%) in the JV group, and none in the KD group demonstrated complete occlusion. Retrospective analysis of the data showed no statistically significant differences in perioperative morbidity, mortality, or early postoperative restenosis whether the artery was closed with saphenous vein, jugular vein, or knitted Dacron patches. Longer follow-up is needed to determine whether rates of late restenosis and aneurysmal dilation will differ between synthetic and autologous patches.

Aged↗
PubMed1995

Carotid endarterectomy in the presence of a contralateral occlusion: a review of 315 cases over a 27-year experience.

Recent data from the North American Symptomatic Carotid Endarterectomy Trial revealed a 14.3% perioperative risk of stroke or death with carotid endarterectomy contralateral to a carotid artery occlusion. Since last reporting on this topic in the mid-1980s, the authors have reviewed 180 patients with occlusion of one internal carotid artery (ICA) and who underwent endarterectomy of the stenotic contralateral ICA operated from 1965 to 1984 (group A) compared with 135 operated on from 1985 to 1991. The two groups were similar with respect to age, sex, incidence of coronary artery disease, hypertension, diabetes and history of smoking, but group B had a significantly increased incidence of patients who were neurologically symptom-free before surgery (21.5% versus 7.8%, P < 0.001). The combined perioperative stroke or death rate for patients in group B was significantly lower than for those in group A (0.7% versus 6.7%, P < 0.01). Comparison of the operative techniques showed more frequent placement of intra-arterial shunt (52.6% versus 29.4%, P < 0.001) and increased use of general anesthesia (20.0% versus 9.4%, P < 0.01) in patients of group B. Analysis of the etiology of the complications, however, showed that shunting alone could not account for the improved results. Lower incidences of postoperative thrombosis, embolization and intracerebral hemorrhage were equally important.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Vessel Prosthesis↗
PubMed1995

Long-term follow-up of patients undergoing carotid endarterectomy in the presence of a contralateral occlusion.

BACKGROUND: Patients with stenosis of one carotid artery and occlusion of the contralateral carotid artery (stenosis-occlusion) who are treated medically are at high risk for stroke. We have recently reported that carotid endarterectomy on the stenotic artery has a low perioperative risk in these patients. We now present follow-up data to define the long-term effectiveness of this operation. PATIENTS AND METHODS: From 1985 to 1991, 135 patients with stenosis-occlusion underwent endarterectomy of the stenotic carotid artery. Selective intra-arterial shunting was performed based on mental status changes under regional anesthesia, preoperative neurologic deficit, or evidence of preoperative cerebral infarction on computed tomography scan. Shunting was used in 70 patients (52%). Saphenous vein was used for patch closure in 132 patients (98%), and polytetrafluoroethylene in 3 (2%). RESULTS: By life-table analysis, 92% of patients have remained stroke-free at 5 years. Fourteen deaths, none related to cerebrovascular disease, have occurred during follow-up. The life-table cumulative stroke-free survival rate at 5 years is 74%, and the overall survival rate is 82%. CONCLUSION: Carotid endarterectomy in the presence of a contralateral occlusion provides long-term benefit to the patient with respect to prevention of stroke. With lower perioperative stroke rates and proven long-term benefit, carotid endarterectomy of the stenotic artery should be the treatment of choice in the patient with stenosis-occlusion.

Aged↗
PubMed1995

MR angiography in carotid stenosis. A clinical prospective.

MR angiography is a major advancement in the diagnosis and treatment of patients with carotid artery stenosis. It has become the major preoperative diagnostic test for these patients. An understanding of the principles of MR imaging allows the clinician to overcome the occasional drawback of MR angiography. Use of MR imaging with duplex scanning allows the surgeon to have an extremely accurate image of the carotid artery bifurcation. Studies conclude that by using these tests as the preoperative assessment for the patient undergoing carotid artery endarterectomy, the procedure is performed with decreased complication, as the risks of conventional cerebral angiography are avoided.

Arterial Occlusive Diseases↗
PubMed1994

Immediate and long-term results of carotid endarterectomy for asymptomatic high-grade stenosis.

We examined the operative risks and long-term results of carotid endarterectomy for asymptomatic patients in terms of stroke, death, and recurrent stenosis. The results of a nonrandomized study with a follow-up of 1 to 104 months (mean 46 months) is reported. A tertiary referral center served as the setting for this report. One hundred consecutive patients with severe but asymptomatic carotid artery stenosis out of a total of 514 patients undergoing carotid endarterectomy were entered into this study. The severity of carotid disease was determined by duplex scanning and confirmed arteriographically. No patients were lost to follow-up after surgery. Eighty-nine operations (77%) were done under cervical block anesthesia and all arteries were closed with saphenous vein patches. Life-table analysis showed that the stroke-free rate at 5 years was 96.3% with an ipsilateral stroke-free rate of 98.2%. The 5-year overall survival rate was 78.2% with a stroke-free survival rate of 75%. Carotid endarterectomy can be performed safely for asymptomatic patients believed to be at risk for stroke. The potential for early death due to myocardial disease, late stroke, and recurrent stenosis do not justify advising patients against undergoing prophylactic carotid endarterectomy for asymptomatic high-grade stenosis.

Aged↗
PubMed1994

The cause of perioperative stroke after carotid endarterectomy.

PURPOSE: The purpose of this study was to examine the cause of perioperative stroke after carotid endarterectomy. METHODS: The records of 2365 patients undergoing 3062 carotid endarterectomies from 1965 through 1991 were reviewed. Sixty-six (2.2%) operations were associated with a perioperative stroke. The mechanism of stroke was determined in 63 of 66 cases. Patient risk factors and surgeon-dependent factors were analyzed. RESULTS: More than 20 different mechanisms of perioperative stroke were identified, but most could be grouped into broad categories of ischemia during carotid artery clamping (n = 10), postoperative thrombosis and embolism (n = 25), intracerebral hemorrhage (n = 12), strokes from other mechanisms associated with the surgery (n = 8), and stroke unrelated to the reconstructed artery (n = 8). Dividing the operative experience approximately into thirds, during the years 1965 to 1979, 1980 to 1985, and 1986 to 1991 the perioperative stroke rates were 2.7%, 2.2%, and 1.5%, respectively. This, in part, is associated with a better selection of patients (more symptom free, fewer with neurologic deficits). There has been a notable decrease in perioperative stroke caused by ischemia during clamping and intracerebral hemorrhage, but postoperative thrombosis and embolism remain the major cause of neurologic complications. CONCLUSIONS: Although patient selection seems to play a role, most perioperative strokes were due to technical errors made during carotid endarterectomy or reconstruction and were preventable.

Aged↗
PubMed1994

Is there detrimental gender bias in preoperative cardiac management of patients undergoing vascular surgery?

BACKGROUND: To investigate the possibility of gender bias in the cardiac management of patients who undergo peripheral vascular surgery, we examined the hospital data and outcomes for 350 adult men and 128 women who underwent vascular surgery from September 1987 to December 1991. METHODS AND RESULTS: There were no significant differences between the two groups in age at operation, incidence of standard risk factors for myocardial infarction, or incidence or duration of episodes of perioperative silent ischemia. Nevertheless, a significantly lower percentage of women than men had undergone prior coronary bypass procedures (6.3% and 17.1%, respectively; P < .01), an apparent example of gender bias. However, there was no significant difference in the incidence of perioperative myocardial infarction in women (3.9%) compared with men (4.0%). Furthermore, actuarial analysis showed that at 24 months after operation a significantly higher percentage of women (77.9%) had escaped late cardiac death and cardiac complications than men (71.9%; P < .05). CONCLUSIONS: These findings indicate that apparent gender bias in the preoperative cardiac management of this group of women who underwent vascular surgery may have had no detrimental effect on short- and long-term incidence of cardiac death and complications, and may represent sound clinical judgment rather than true bias. However, the possibility that female patients might have had even better short- and long-term cardiac results if they had undergone more preoperative cardiac revascularization cannot be discounted.

Actuarial Analysis↗
PubMed1994

3. Surgical management of internal carotid artery stenosis: preventing complications.

Although the North American Symptomatic Carotid Endarterectomy Trial and the European Collaborative Trial demonstrated the efficacy of carotid surgery for the prevention of stroke in patients with symptomatic high grade stenosis, it is important to remember that within the surgical arms of these studies the perioperative stroke rate was 5.5% and 7.5% respectively. Few studies have addressed the factors responsible for perioperative stroke. In a recent report from our institution, 66 of 3062 carotid endarterectomies were complicated by perioperative stroke. Of these, 65% were due to a failure in surgical technique. The mechanisms of failure included ischemia during carotid clamping (10), postoperative thrombosis and embolism (25) and other factors (8). Strokes not related to technical failures were due to reperfusion injuries and intracranial hemorrhage (12) and other events in the postoperative period (30 days). Specific problems and possible solutions are discussed. Further improvements in the technique of carotid endarterectomy may lead to lower complication rates and a wider acceptance of surgery for the prevention of stroke.

Carotid Artery, Internal↗
PubMed1993

Plasma catecholamine concentrations during abdominal aortic aneurysm surgery: the link to perioperative myocardial ischemia.

Cardiac disease continues to be the leading cause of morbidity and mortality following peripheral vascular surgical procedures. Although the mechanism of sudden myocardial infarction remains elusive, many possibilities exist. The role of catecholamines is intriguing in view of the evidence that beta-adrenergic blockers reduce cardiac morbidity and mortality in vascular surgical patients. To ascertain whether the plasma catecholamine levels rise significantly during abdominal aortic aneurysm repair, serial determinations of plasma epinephrine and norepinephrine levels were performed in 18 patients. Epinephrine levels rose significantly from preoperative baseline values both during the operation and postoperatively, and norepinephrine levels rose significantly at 24 hours postoperatively. Although only one patient studied developed a myocardial infarction, the finding that patients undergoing aortic surgery uniformly experienced abnormally high serum catecholamine levels supports other evidence that perioperative myocardial ischemic events have a hormonal component.

Aortic Aneurysm, Abdominal↗