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Biomedical subjects

L M Taylor

Publications and source records attributed to L M Taylor.

At least 37 records · Page 2Linked to original sources

Prospective blinded study of the relationship between plasma homocysteine and progression of symptomatic peripheral arterial disease.

PURPOSE: An elevated plasma homocysteine level is an established risk factor for atherosclerotic coronary heart disease (CHD), cerebrovascular disease (CVD), and lower extremity occlusive disease (LED). An elevated plasma homocysteine level can be reduced by therapy with folate and vitamins B6 and B12. An accurate evaluation of the role of vitamin therapy requires knowledge of the influence of plasma homocysteine levels on the progression of CHD, CVD, and LED. METHODS: The Homocysteine and Progression of Atherosclerosis Study is a blinded prospective study of the influence of homocysteine and of other atherosclerotic risk factors on the progression of disease in patients with symptomatic CVD, LED, or both. This study is set in a university hospital vascular surgery clinic and the General Clinical Research Center. Consecutive patients with stable symptomatic CVD or LED underwent baseline clinical, laboratory, and vascular laboratory testing for homocysteine and other risk factors and were examined every 6 months. The primary endpoints were ankle brachial pressure index, duplex scan-determined carotid stenosis, and death. The secondary endpoints were the clinical progressions of CHD, LED, and CVD. The hypothesis that was tested was whether the progression of symptomatic CVD or LED was more frequent or more rapid in patients with elevated plasma homocysteine levels. plasma homocysteine levels. RESULTS: After a mean follow-up period of 37 months (range, 1 to 78 months) for deaths from all causes (>14 micromol/L; elevated, 18.6%; normal, 9.4%; P = .022), deaths from cardiovascular disease (elevated, 12.5%; normal, 6.3%; P = .05) and the clinical progression of CHD (highest 20% of homocysteine levels, 80%; lowest 20% of homocysteine levels, 39%; P = .007) were significantly more frequent or more rapid by life-table analysis when the homocysteine levels were elevated. Multivariate Cox proportional hazards regression model showed a significant independent and increasing relationship between the plasma homocysteine levels and the time to death (relative risk for highest one third of homocysteine values, 1.6; 95% confidence interval [CI], 1.04 to 2.56; P = 029; and relative risk for highest one fifth of homocysteine values, 3.13; 95% CI, 1.69 to 6.64; P = .0001). After an adjustment for age, smoking, hypertension, diabetes, cholesterol, and the vascular laboratory progression of CVD or LED, each 1.0 micromol/L increase in the plasma homocysteine levels resulted in a 3.6% increase (95% CI, 0.0% to 6.6%; P = .06) in the risk of death (all causes) at 3 years and a 5.6% increase (95% CI, 2.2% to 8.5%; P = .003) in the risk of death from cardiovascular disease. CONCLUSION: We conclude that elevated plasma homocysteine levels are associated significantly with death, with death from cardiovascular disease, and with the progression of CHD in patients with symptomatic CVD or LED. These results strongly mandate clinical trials of homocysteine-lowering vitamin therapy in such patients.

Aged↗

Duplex scanning alone is not sufficient imaging before secondary procedures after lower extremity reversed vein bypass graft.

PURPOSE: Duplex surveillance of lower extremity reversed vein bypass grafts (LERVG) is a means of identifying patients at risk for occlusion. The perceived accuracy of duplex scan as a means of identifying stenoses has led many surgeons to perform graft revision on the basis of duplex scan alone. This may result in missing additional lesions that are threatening patency. To assess the role of duplex scan as the sole imaging method before revision of LERVGs, we reviewed consecutive patients undergoing revisions who underwent preoperative arteriography after identification of duplex scan abnormalities. METHODS: Duplex scan results, operative reports, and preoperative arteriograms for patients undergoing LERVG revision from January 1990 to December 1997 were reviewed. A standard duplex scan surveillance protocol was followed, and attempts were made to survey the entire graft, including inflow and outflow. Duplex scan results were compared with the results of preoperative arteriograms and the operation performed to determine if all significant lesions were identified by means of duplex scan alone. RESULTS: Two hundred five LERVG revisions were performed. The 5-year assisted primary patency rate was 91%. In 119 cases (58%), arteriography did not contribute significantly to duplex scan findings. Arteriography significantly contributed to operative planning in 86 cases (42%). In 38 cases (19%), only a low-flow state was identified by means of duplex scan, and a correctable stenosis was identified by means of arteriography. In 48 cases (23%), additional significant lesions corrected at operation were identified by means of arteriography. These included 26 inflow, 16 graft, and 8 outflow lesions. Arteriography was most useful as a means of determining the revision procedure performed when there were inflow lesions (P <.05) or when the proximal anastomosis was to the profunda or superficial femoral arteries (P <.05). All frequently performed bypass graft configurations had some discrepancy between arteriographic and duplex scan findings. CONCLUSION: Available data do not permit prediction of which LERVG are immune from missed lesions in a duplex scan surveillance protocol. This suggests to us that arteriography is mandatory before LERVG revisions.

Aged↗

Predictors of outcome of forefoot surgery for ulceration and gangrene.

BACKGROUND: Surprisingly little is known about the long-term outcome of forefoot surgery for limb salvage. METHODS: From January 1, 1992 through December 31, 1996, patients requiring toe amputation or forefoot surgery were prospectively entered into a computerized database and followed up for healing, need for repeat foot surgery, or major amputation (below or above knee). RESULTS: A total of 162 patients (mean age 65 years), 72% diabetic, 10% with end-stage renal disease (ESRD), and 73% without palpable pulses, were entered into the study. Mean follow-up was 25 months. Of patients without palpable pulses (n = 98), 83% underwent concomitant or subsequent limb revascularization. Eleven of 98 revascularization procedures (11%) were hemodynamically unsuccessful. Nonhealing of the initial forefoot procedure occurred in 14%, and late repeat foot surgery (following initial healing) was required in an additional 14%. Major amputation was eventually required in 30 (18.5%) patients. Multivariate analysis indicated that unsuccessful revascularization, but not diabetes or ESRD, predicted nonhealing and major amputation (P <0.0001). Patients presenting with palpable pulses and neuropathic ulcers were at risk for late, repeat foot surgery, but not major amputation (P = 0.0015). CONCLUSIONS: In patients requiring toe or partial forefoot amputation, success of revascularization is the primary predictor of initial healing and freedom from major amputation. Neuropathic ulceration predicts need for repeat foot surgery following healing.

Adult↗

Surgical treatment of infected aortic aneurysm.

BACKGROUND: We report results of infected aortic aneurysms treated by a single group over 20 years. METHODS: Retrospective review. RESULTS: Seventeen patients were treated, 10 with infrarenal and 7 suprarenal infections. All had abdominal/back pain, 88% were febrile, 71% had leukocytosis, and 24% were hemodynamically unstable. The most common responsible organism was Staphylococcus aureus (29%) followed by Salmonella organisms (24%). All suprarenal infections were gram-positive organisms. Infrarenal infections were treated with preliminary axillofemoral bypass followed by aortic resection. Suprarenal infections were treated with either in situ prosthetic graft or patch repairs. Operative survival was 90% for infrarenal and 57% for suprarenal infections. Operative deaths occurred in the setting of overwhelming sepsis and/or severe preoperative hemodynamic instability. There was no limb loss, renal failure, or intestinal ischemia. Late deaths occurred in 4 patients at 1.3 to 6.3 years postoperatively and were unrelated to their aortic repairs. Nine patients remain alive with a median follow-up of 2 years. There have been no late aortic or graft infections. CONCLUSIONS: In the absence of hemodynamic instability and uncontrolled sepsis, infected aortic aneurysms can be successfully repaired with durable results.

Adult↗

Inferior epigastric artery pseudoaneurysm: a complication of paracentesis.

Two patients had inferior epigastric artery pseudoaneurysms after therapeutic paracentesis for ascites caused by portal hypertension. The first patient, a 62-year-old man, had a two-week history of left lower quadrant pain, tenderness, and nonpulsatile mass after a paracentesis for ascites. A left inferior epigastric artery pseudoaneurysm measuring 10 cm in diameter and 20 cm in length was diagnosed by means of Duplex ultrasound and arteriography. The patient was treated with percutaneous embolization, with successful thrombosis of the pseudoaneurysm. The second patient, a 33-year-old woman, had a six-week history of left lower quadrant pain, tenderness, and nonpulsatile mass after a paracentesis for ascites. Computerized tomography and arteriography showed a left inferior epigastric artery pseudoaneurysm, measuring 7 cm in diameter and 9 cm in length. The patient was treated with percutaneous embolization with successful thrombosis of the pseudoaneurysm. Both patients were discharged in good condition 2 days after embolization. Inferior epigastric artery pseudoaneurysm is a complication of paracentesis, and percutaneous embolization may be preferable to surgical repair in patients with chronic liver failure and portal hypertension.

Adult↗

Prophylactic repair of renal artery stenosis is not justified in patients who require infrarenal aortic reconstruction.

PURPOSE: Simultaneous prophylactic repair of asymptomatic renal artery stenosis (ARAS) in patients who require infrarenal aortoiliac reconstruction is controversial. This study documents the natural history of ARAS in patients who require aortic reconstruction. METHODS: Two hundred patients who required aortic reconstruction from 1985 to 1990 for indications other than hypertension or renal salvage were identified. ARAS was not repaired. Preoperative angiograms were available for 171 of 200 patients and were reviewed for renal artery stenosis. Patients were assessed for atherosclerotic risk factors, survival, preoperative and follow-up blood pressure, serum creatinine level, antihypertensive medication usage, and need for dialysis. RESULTS: The mean duration of follow-up was 6.3 years. Twenty-four of 171 patients (14%) had preoperative unilateral 70% to 99% diameter reduction ARAS, and eight (5%) had bilateral 70% to 99% ARAS. Clinical features associated with > or =70% ARAS included coronary artery disease, increased age, and a diagnosis of hypertension (p < 0.05). Patients with > or =70% ARAS did not have a decreased 7-year survival rate (66% vs 84%; p = 0.10) but had higher systolic blood pressures (153 +/- 25 vs 138 +/- 30 mm Hg; p < 0.05) as well as increased numbers of antihypertensive medications at follow-up (1.1 +/- 0.2 vs 0.7 +/- 1; p < 0.05). The mean serum creatinine level (1.1 +/- 0.3 preoperative vs 1.4 +/- 0.8 mg/dl; p = NS) was not increased. One patient (0.58%) with polycystic kidney disease and minimal renal artery stenosis required dialysis. CONCLUSIONS: High-grade ARAS in patients who are undergoing infrarenal aortic reconstruction is associated at late follow-up with increased systolic blood pressure and a need for increased numbers of antihypertensive medications, but not decreased survival rate, dialysis dependence, or an increase in serum creatinine level. These data do not support renal artery repair in patients with ARAS who undergo infrarenal aortic reconstruction.

Aorta, Abdominal↗

Interposition grafting for reoperation on the common femoral artery.

PURPOSE: This report details our experience with common femoral artery resection and Dacron interposition grafting in the management of vascular reoperations involving the common femoral artery. DESIGN: Retrospective review. SETTING: University teaching hospital. SUBJECTS: Consecutive reoperative patients who had common femoral artery interposition grafting for arteriosclerotic occlusive disease from 1986 to 1997. INTERVENTIONS: Common femoral artery resection and interposition grafting. MAIN OUTCOME MEASURES: Operative morbidity and mortality rates and long-term patency, limb salvage, patient survival, freedom-from-graft-infection, and freedom-from-reoperation rates. RESULTS: Ninety-nine common femoral arteries (16 bilateral) were resected and replaced with Dacron interposition grafts in 83 patients (50 male, 33 female; mean age, 65 years) who had had 237 previous ipsilateral common femoral artery operations (mean, 2.4 operations; range, 1-9 operations). Simultaneous infrainguinal bypass grafts were performed in 52 operations (53%), and 60 operations (61%) were performed in patients who had had previous ipsilateral proximal bypass grafts. Operative mortality was 2%, with a 14% rate of perioperative wound complications. Mean follow-up time was 22 months. One- and 3-year assisted primary patency rates for the interposition grafts were 90% and 77%, respectively. Both 1- and 3-year life-table-determined limb salvage rates were 95%. One- and 3-year life-table-determined freedom-from-reoperation rates were 74% and 43%, respectively. One- and 3-year life-table-determined freedom-from-infection rates were 99% and 92%, respectively. One- and 3-year life-table-determined survival rates were 82% and 73%, respectively. CONCLUSIONS: Common femoral artery resection and Dacron interposition grafting are safe, and they obviate many difficulties associated with reoperative common femoral artery surgery with satisfactory long-term results.

Adult↗

Late clinical and hemodynamic sequelae of isolated calf vein thrombosis.

PURPOSE: Despite the frequent occurrence of isolated calf vein thrombosis (ICVT), little is known about the long-term clinical and hemodynamic sequelae of this condition. This study was conducted to determine late clinical symptoms and vascular laboratory abnormalities in patients after ICVT. METHODS: Of 146 patients in whom ICVT was documented by color flow duplex scanning between 1989 and 1994, 37 were reexamined. Data included history, physical examination, venous recovery time (VRT), and duplex valve closure time (DVCT). A control group with no history of venous disease also underwent identical clinical and hemodynamic testing. RESULTS: Thirty-seven patients (18 male and 19 female) with a median age of 56 years (range, 22 to 76 years) were examined at a mean follow-up of 3.4 years (range, 2.2 to 5.8 years) after the diagnosis of ICVT in 39 extremities. Seventeen subjects (34 extremities) were recruited as normal controls. Presenting symptoms at the time of ICVT included calf pain in 17 patients, calf swelling in seven, pain and swelling in seven, pulmonary symptoms in four, pulmonary symptoms and calf pain in one, and no symptoms in one. In the patients with ICVT, VRT was abnormal in 23% of extremities with ICVT and in 9% of extremities without ICVT. None of the extremities in the control group had an abnormal VRT (p < 0.05). DVCT was abnormal in one or more venous segments in 26% of extremities diagnosed with ICVT and in 6% of control extremities (p < 0.05). Follow-up clinical examination in patients with ICVT revealed 13 (35%) with reticular veins, 10 (27%) with varicose veins, two (5.4%) with edema, one (2.7%) with pigmentation and ulcer (contralateral extremity to ICVT with a previous history of proximal deep venous thrombosis), 13 (35%) with mild discomfort, and one (2.7%) with severe pain. All symptoms attributable to ICVT were mild in nature except in one patient who had severe pain and no physical or hemodynamic vascular laboratory abnormalities at follow-up. CONCLUSION: At an average of 3.4 years after ICVT, approximately one third of patients showed evidence of mild to moderate venous valvular insufficiency, but mostly in segments not involved with ICVT, and few had significant clinical symptoms attributable to venous disease.

Adult↗

Patient recovery after infrainguinal bypass grafting for limb salvage.

PURPOSE: The outcome of infrainguinal bypass surgery for limb salvage has traditionally been assessed by graft patency rates, limb salvage rates, and patient survival rates. Recently, functional outcome of limb salvage surgery has been assessed by patient ambulatory status and independent living status. These assessments fail to consider the adverse long-term patient effects of delayed wound healing, episodes of recurrent ischemia, and need for repeat operations. An ideal result of infrainguinal bypass surgery for limb salvage includes an uncomplicated operation, elimination of ischemia, prompt wound healing, and rapid return to premorbid functional status without recurrence or repeat surgery. The present study was performed to determine how often this ideal result is actually achieved. METHODS: The records of 112 consecutive patients who underwent initial infrainguinal bypass surgery for limb salvage 5 to 7 years before the study were reviewed for operative complications, graft patency, limb salvage, survival, patient functional status, time to achieve wound healing, need for repeat operations, and recurrence of ischemia. RESULTS: The mean patient age was 66 years. The mean postoperative follow-up was 42 months (range, 0 to 100.1 months). After operation 99 patients (88%) lived independently at home and 103 (92%) were ambulatory. There were seven perioperative deaths (6.3%), and wound complications occurred in 27 patients (24%). By life table, the assisted primary graft patency and limb salvage rates of the index extremity 5 years after operation were 77% and 87%, respectively, and the patient survival rate was 49%. At last follow-up or death, 73% of the patients (72 of 99) who lived independently at home before the operation were still living independently at home, and 70% (72 of 103) of those who were ambulatory before the operation remained ambulatory. Wound (operative and ischemic) healing required a mean of 4.2 months (range, 0.4 to 48 months), and 25 patients (22%) had not achieved complete wound healing at the time of last follow-up or death. Repeat operations to maintain graft patency, treat wound complications, or treat recurrent or contralateral ischemia were required in 61 patients (54%; mean, 1.6 reoperations/patient), and 26 patients (23.2%) ultimately required major limb amputation of the index or contralateral extremity. Only 16 of 112 patients (14.3%) achieved the ideal surgical result of an uncomplicated operation with long-term symptom relief, maintenance of functional status, and no recurrence or repeat operations. CONCLUSIONS: Most patients who undergo infrainguinal bypass surgery for limb salvage require ongoing treatment and have persistent or recurrent symptoms until their death. A significant minority have major tissue loss despite successful initial surgery. Clinically important palliation is frequently achieved by bypass surgery, but ideal results are distinctly infrequent.

Activities of Daily Living↗

Iatrogenic vascular trauma.

With the increasing performance of percutaneous transluminal angioplasty and insertion of an increasing number of intravascular devices, the size of arterial punctures has been increasing. A consistent minority of these procedures will result in vascular injuries requiring treatment. At the same time, the regionalized nature of trauma care in the United States has resulted in a large number of vascular surgeons who are exposed to vascular trauma only when iatrogenic. The most common injuries observed are caused by percutaneous vascular instrumentation and include hemorrhage and pseudoaneurysm that may compress adjacent structures, fistula, acute occlusion, and embolization. Injuries unique to balloon angioplasty/stenting include arterial rupture and dissection. Indwelling intravascular devices are another common source of iatrogenic vascular injury ranging from arterial rupture to thrombosis and embolization. Much less common injuries are observed in orthopedic and abdominal/laparoscopic operations but show reproducible causes/patterns. Finally, pediatric iatrogenic vascular trauma is relatively common because of the small size of the vasculature, but the natural history and management is markedly different from that in adults.

Arterial Occlusive Diseases↗

Upper extremity ischemia from subclavian artery aneurysm caused by bony abnormalities of the thoracic outlet.

OBJECTIVE: To describe our experience with surgical therapy for upper extremity ischemia incident to emboli from aneurysms of the subclavian artery. DESIGN: Retrospective review case series. SETTING: Vascular surgery practice at a university hospital-based tertiary referral center. PATIENTS: All patients treated for upper extremity ischemia caused by embolism from a subclavian artery aneurysm from January 1, 1990, to July 31, 1996. INTERVENTION: All patients underwent detailed history and physical examination, screening for immunologic and hypercoaguable disorders, noninvasive vascular laboratory evaluation, and arteriography of the aortic arch in both arms and hands. Surgical treatment consisted of rib excision or fracture plating, aneurysm excision, and interposition vein grafting, with additional saphenous vein bypasses to brachial or forearm arteries as needed to provide uninterrupted circulation to the wrist. RESULTS: Twelve patients (6 males; mean age, 37 years) were treated. All had episodic upper extremity ischemia with an initial misdiagnosis of primary vasospastic disorder. Rest pain and/or ischemic ulceration developed in 3. Duration of symptoms before correct diagnosis averaged 7 months (range, 1-36 months). All patients had bony abnormalities of the thoracic outlet (8 cervical ribs, 3 abnormal first ribs, and 1 unstable clavicular fracture). All aneurysms contained intraluminal thrombus, and all patients had multiple ipsilateral distal arm, forearm, and/or hand arterial occlusions indicating chronic and repeated embolization. All patients underwent aneurysm excision and interposition vein grafting, with additional vein bypass to the brachial (3 patients) and/or forearm arteries (5 patients). Mean follow-up was 18 months (range, 2 weeks to 63 months). Eleven patients had complete symptomatic relief, and 1 patient improved. All subclavian interposition grafts remained patient. Two distal bypass grafts occluded in patients with preoperative arteriograms demonstrating no patient forearm arteries. There has been no limb loss. CONCLUSIONS: Hand ischemia caused by embolization from a subclavian artery aneurysm occurs in young patients without atherosclerosis and is frequently misdiagnosed as vasospasm. Despite advanced disease and multiple chronic distal arterial occlusions, surgical treatment by resection of bony abnormalities, aneurysm excision and grafting, and distal bypass grafting produces excellent results.

Adolescent↗

Ability of ankle-brachial index to detect lower-extremity atherosclerotic disease progression.

BACKGROUND: Accurate determination of progression of lower-extremity arterial occlusive disease (LEAOD) is required for natural history studies and evaluation of therapies for atherosclerosis. OBJECTIVE: To determine if changes in the ankle-brachial index (ABI) correlated with progression of LEAOD as determined by arteriography or duplex scanning. DESIGN: In patients with prior suprainguinal or infrainguinal lower-extremity revascularization, progression of LEAOD in native arteries was determined by comparing a preoperative (baseline) arteriogram with late follow-up arteriography or duplex scanning. Superficial femoral and popliteal arteries were graded as having less than 50% stenosis, 50% to 99% stenosis, or as being occluded. Tibial arteries were graded as continuously patent or occluded. Operated and nonoperated extremities were included in the study. The baseline ABI was performed postoperatively and repeated at follow-up arteriography or duplex scanning. Progression of LEAOD by the ABI was defined as a decrease in the ABI of 0.15 or greater. Progression of LEAOD by imaging studies was defined as an increase in 1 category of stenosis. Extremities with suprasystolic pressures were excluded. SETTING: Tertiary vascular surgical service. EXTREMITIES AND PATIENTS: One hundred ninety-three extremities were studied in 114 patients during a mean follow-up of 3.3 years. RESULTS: Seventy-two lower extremities (37.3%) showed progression of atherosclerosis by late follow-up arteriography or duplex scanning. Using the imaging studies as the criterion standard, the ABI had 102 true negatives, 29 true positives, 42 false negatives, and 20 false positives (sensitivity, 41%; specificity, 84%; positive predictive value, 59%; negative predictive value, 71%; and accuracy, 68%) for determining the progression of LEAOD. CONCLUSIONS: The ABI is relatively insensitive in identifying the progression of LEAOD as demonstrated by the use of imaging studies. In studies of natural history or therapy for atherosclerosis, imaging studies should be used in preference to the ABI to evaluate the progression of LEAOD accurately.

Adult↗

Duplex ultrasonography in evaluation of splanchnic artery stenosis.

Duplex ultrasonography accurately identifies high-grade stenoses in the SMA. Analysis of velocity data reveals few false positives and virtually no false negatives in the determination of high-grade SMA stenosis by duplex scanning. We therefore utilize duplex scanning to perform early screening studies of patients with symptoms suggestive of chronic visceral ischemia. If the duplex findings are negative, we recommend evaluating for other sources of abdominal pain. If the findings are positive, prompt angiography is indicated. It is important to remember that although duplex scanning can identify mesenteric artery stenosis, it cannot diagnose intestinal ischemia. By establishing duplex scanning as a useful and accessible noninvasive screening tool, it is hoped that the time between onset of visceral ischemic symptoms and diagnosis of chronic visceral ischemia will be shortened significantly, potentially reducing the morbidity and mortality of the disease.

Blood Vessel Prosthesis↗

Pulmonary embolism is associated with the combination of isolated calf vein thrombosis and respiratory symptoms.

PURPOSE: Overall prevalence of pulmonary embolism (PE) in patients with deep venous thrombosis (DVT) isolated to calf veins is low. However, the prevalence of PE in the subgroup of patients with respiratory symptoms and isolated calf vein thrombosis (CVT) is unknown. Such information is important in determining whether patients with CVT only and respiratory symptoms should undergo evaluation for PE. The purpose of this study was to determine the prevalence of PE in patients with respiratory symptoms and isolated CVT. METHODS: From 1992 through 1994, all patients assessed by duplex scanning for lower extremity DVT were reviewed, and those found to have isolated CVT and lower extremity or respiratory symptoms were identified. Patients who had respiratory symptoms or later developed respiratory symptoms in addition to lower extremity symptoms underwent pulmonary angiography or ventilation/perfusion (V/Q) scanning. Positive results on pulmonary arteriograms or "high probability" V/Q scans were considered diagnostic of PE. RESULTS: There were 105 patients with isolated CVT and symptoms. Twenty-six patients had respiratory symptoms; nine (35%) had PE and two died. Seventy-nine patients had only lower extremity complaints; five later developed respiratory symptoms. All five had PE and none had progression of CVT on repeat duplex scanning. Neither age, gender, prior DVT/PE, obesity, pregnancy, medication, known malignancy, smoking, recent surgery, or trauma predicted PE. CONCLUSIONS: Patients with respiratory symptoms and duplex diagnosed isolated CVT have a high prevalence of PE and require pulmonary angiographic or V/Q scanning to rule out PE.

Adult↗

Functional outcome after infrainguinal bypass for limb salvage.

PURPOSE: Functional outcome after infrainguinal bypass (IB) has recently been assessed with global health status questionnaires but not by criteria specific to the objectives of IB (i.e., maintenance of independent living and ambulation). Preoperative and postoperative living situation and ambulatory status were evaluated in patients who underwent IB for limb salvage (LS) indications. METHODS: For patients in whom IB was performed for LS from January 1980 to July 1995, living situation (independent or dependent) and ambulatory status were assessed before the onset of the need for LS surgery and 6 months after surgery. The importance of risk factors (age, sex, diabetes, heart disease, hypertension, renal insufficiency or failure, previous leg bypass, indication for surgery, postoperative morbidity, graft patency) was assessed by multivariate analysis. RESULTS: IB for LS was performed in 513 patients. Before the development of the indication for LS surgery, 92% lived independently and 91% were ambulatory. The operative mortality rate was 2.7%. At 6 months, 86% were alive and the assisted primary graft patency rate was 92%. Ninety-nine percent of survivors who lived independently before developing the need for LS surgery remained independent 6 months after surgery, and 97% of those who were ambulatory before developing the need for LS surgery were ambulatory 6 months after surgery. Only one of 25 survivors (4%) who were not living independently before surgery achieved independent living 6 months after surgery. Twenty-one percent of nonambulatory patients (6 of 29) became ambulatory. Multivariate analysis confirmed the importance of preoperative living situation and ambulatory status in predicting outcome at 6 months (p < 0.0001). Amputation and loss of primary patency were predictive of poor ambulatory status at 6 months (p < 0.0001, p = 0.025, respectively). The overall 5-year survival rate was 48.1%. CONCLUSIONS: Preoperative independence and ambulation best predict postoperative independence and ambulation after IB for LS indications. IB procedures performed for limb salvage have a low operative mortality rate and maintain independent living and ambulation in 99% and 97% of patients, respectively. Poor overall long-term outcome and survival in LS patients results from intercurrent illness and not from IB.

Activities of Daily Living↗

Homocysteinemia as a risk factor for atherosclerosis: a review.

In industrialized nations, the leading cause of death and disability is atherosclerosis. Despite a widespread research effort spanning decades, there remains no clearly defined cause or cure for this disease that directly or indirectly affects the lives of almost all individuals in the western world. Autopsy findings show atherosclerosis to some degree in nearly all aged people, suggesting it should be regarded as a normal aging process as well as a disease. Any investigation of atherosclerosis etiology therefore requires a distinction between atherosclerosis normally observed with aging, and pathologic atherosclerosis causing disease and/or death. Atherosclerosis is most appropriately regarded as a disease when associated with both rapid progression and clinical symptoms. Widely accepted risk factors for atherosclerotic disease include advanced age, diabetes, tobacco use, arterial hypertension, hypercholesterolemia, hypertriglyceridemia, decreased high-density lipoprotein, some hypercoaguable states, sedentary life-style, and elevated plasma homocysteine. The study of lipid metabolism has dominated research into atherosclerosis etiology for decades, although now it is widely recognized that a large number of people with symptomatic atherosclerotic disease have no detectable evidence of abnormal lipid metabolism. Elevation in plasma homocysteine has also been widely studied as an independent risk factor for atherosclerosis. A description of the metabolism of homocysteine, its relationship to vascular disease, evidence supporting its role as an independent risk factor for atherosclerotic vascular disease, and the potential role of treatment will form the basis for this review.

Arteriosclerosis↗

Diagnosis and management of ureteroiliac artery fistula: value of provocative arteriography followed by common iliac artery embolization and extraanatomic arterial bypass grafting.

PURPOSE: We describe an effective multidisciplinary approach to the diagnosis and management of ureteroarterial fistulas that reduces morbidity and mortality. MATERIALS AND METHODS: Five ureteroarterial fistulas in 4 patients were studied with standard and provocative arteriography (arteriography combined with ureteral manipulation). After establishing the diagnosis, each lesion was treated with percutaneous embolic occlusion of the common iliac artery followed by extraanatomic arterial bypass grafting. All patients had chronic ureteral stenting, prior pelvic irradiation, prior pelvic surgery and intrapelvic malignancy, and all fistulas presented with urinary tract hemorrhage. RESULTS: Standard arteriography was nondiagnostic but provocative arteriography demonstrated the fistula in each case. Successful embolization of the common iliac artery followed by extraanatomic arterial bypass grafting precluded the need for laparotomy and preserved ipsilateral renal function. CONCLUSIONS: Provocative arteriography followed by arteriographic common iliac artery embolization and extraanatomic bypass grafting was successful for the diagnosis and treatment of ureteroarterial fistulas. There was no mortality, limb loss or renal loss.

Adult↗

Common mutation in methylenetetrahydrofolate reductase. Correlation with homocysteine metabolism and late-onset vascular disease.

BACKGROUND: Increased homocysteine levels are a risk factor for atherosclerosis and its sequelae. A common genetic mutation in methylenetetrahydrofolate reductase (MTHFR), an enzyme required for efficient homocysteine metabolism, creates a thermolabile enzyme with reduced activity. We determined the prevalence of this mutation in many subjects with and without vascular disease and related it to homocysteine and folate levels. METHODS AND RESULTS: DNA from 247 older subjects with vascular disease and 594 healthy subjects without vascular disease (in three different control groups) was screened for the MTHFR 677 C-to-T mutation. Within each group, 9% to 17% of the subjects were homozygous for this mutation, and the mutant allele frequency was 31% to 39%. The genotype distributions, homozygote frequencies, and allele frequencies did not differ significantly between the study groups. In the vascular disease subjects, despite significantly lower folate levels in MTHFR homozygotes, there was no significant difference in homocysteine levels among the MTHFR genotype groups. The negative slope of the regression line relating homocysteine and folate was significantly steeper for those with a homozygous MTHFR mutation compared with those without this mutation. CONCLUSIONS: Although the thermolabile MTHFR mutation is very common, it does not appear to be a significant genetic risk factor for typical late-onset vascular disease. Because MTHFR homozygotes have increased homocysteine with low folate levels, this mutation may contribute to early-onset or familial vascular disease. The genotype dependence of the folate-homocysteine correlation further suggests that homozygotes for this mutation may have both an exaggerated hyperhomocysteinemic response to folic acid depletion and a better response to folic acid therapy.

Adult↗