Long-term follow-up of reoperative carotid surgery.

BACKGROUND: We examined our long-term results of carotid reoperation to identify risk factors for morbidity and secondary recurrence. METHODS: Medical record review revealed 27 patients had reoperative surgery for recurrent stenosis. Demographics, operative details, pathology, clinical outcome, and follow-up imaging results were reviewed. RESULTS: No neurologic deficits and no mortalities were noted perioperatively. Long-term follow-up (average 54 months) revealed an 85% 5-year and 29% 10-year estimated survival. The 5- and 10-year estimated neurologic event rates were 15% and 35%, respectively. These included 3 ipsilateral strokes and 1 ipsilateral TIA; only the TIA involved secondary restenosis. Follow-up imaging revealed a 21% incidence of secondary restenosis, occurring more frequently in patients with hyperlipidemia (P < 0.05) and previous contralateral endarterectomy (P < 0.05). CONCLUSIONS: (1) Reoperation provides long-term protection from stroke due to recurrent stenosis. (2) Secondary restenosis rates appear higher than those for primary surgery. (3) Hyperlipidemia and contralateral endarterectomy are risk factors for secondary restenosis.

Early carotid endarterectomy in selected stroke patients.

Although there are several reports suggesting the safety of performing carotid endarterectomy (CE) within 4 weeks (early) of a nondisabling stroke, at many institutions it is not standard practice. Benefits of early surgery may include reduction in the number of strokes or carotid occlusions during the time between stroke and surgery, as well as a reduction in the cost of medical care due to the elimination of interval anticoagulation and close follow-up. This review examines the outcomes of early CE in selected patients after a nondisabling stroke. A total of 1065 CEs were performed between November 1991 and April 1998. Seventy-five patients were identified by computerized hospital record and office chart review as having CE after a nondisabling stroke. Criteria for early surgery included 1) nondisabling stroke ipsilateral to a carotid stenosis >50%, 2) neurological stability, and 3) no evidence of hemorrhagic stroke or significant cerebral edema by CT/MRI evaluation. This review suggests that early CE can be performed in selected patients with an acceptable perioperative morbidity and mortality.

Comparison of Doppler US and CT angiography for evaluation of renal artery stenosis.

RATIONALE AND OBJECTIVES: The authors compared Doppler ultrasound (US) with computed tomographic (CT) angiography in the evaluation of stenosis of the main renal artery. MATERIALS AND METHODS: Fifty-six patients who had undergone conventional angiography of the renal arteries participated in a prospective comparison of Doppler US (45 patients) and CT angiography (52 patients). US evaluation included both the main renal artery and segmental renal arteries. RESULTS: There were 27 main renal arteries with at least 50% stenosis in 20 patients. In 36 patients, there was no significant stenosis. All cases of main renal artery stenosis detected with Doppler US of the segmental arteries were also identified with Doppler US of the main renal artery. The by-artery sensitivity (63%) of US of the main renal artery was greater than that (33%) of US of the segmental arteries. CT angiography was more sensitive (96%) than Doppler US (63%) in the detection of stenosis, but the specificity of CT (88%) was similar to that of US (89%). The difference in the area under the receiver operating characteristic curve (AUC) between CT (AUC = 0.94) and US (AUC = 0.82) was statistically significant (P = .038). CONCLUSION: Doppler US of the main renal artery is more sensitive than Doppler US of segmental arteries in the detection of stenosis. CT angiography is more accurate than Doppler US in the evaluation of renal artery stenosis.

Long-term outcome following sympathectomy for complex regional pain syndrome type 1 (RSD).

We performed a retrospective study of 29 patients with CRPS1 (RSD) who were initially examined between 1983 and 1993, and had either transthoracic (lower third of stellate ganglia to T3) or lumbar (L2-L4) sympathectomy. The patients were followed from 24 to 108 months after surgery. Patients with unsuccessful surgical outcomes had significantly longer duration of symptoms before surgery (median, 36 months) than those with successful outcomes (median, 16 months) by Wilcoxon rank sum test (chi2=8.69, df=1, P<0.01). All seven patients (100%) who had sympathectomy within 12 months of injury, nine of 13 patients (69.2%) who had sympathectomy within 24 months of injury, and only four of nine patients (44.4%) who had sympathectomy after 24 months of injury obtained permanent (greater than 24 months) symptom relief. Patient age, sex, occupation, site of injury, type of injury, presence of trophic changes, and duration of follow-up were not significantly related (P>0.05) to surgical outcome.

Magnetic resonance chemical shift imaging and spectroscopy of atherosclerotic plaque.

An in vivo magnetic resonance imaging (MRI) technique for identification and characterization of atherosclerotic plaque was assessed in animal and human models. Atherosclerosis was induced in the abdominal aorta of four rabbits by a combination of balloon denudation and a high cholesterol diet. In vivo conventional spin-echo and fat/water suppressed images of the rabbit aortae were obtained at 1.5 T. Chemical shift imaging (CSI) was achieved using a hybridization of selective excitation and modified Dixon techniques. These techniques were then used to obtain images of atherosclerotic lesions in the carotid arteries of four patients prior to endarterectomy. The MRI results were corroborated by histologic and high-resolution proton MR spectroscopic (8.5 T) analysis of rabbit aorta, human carotid endarterectomy, and six additional human superficial femoral and iliac atherectomy specimens. All animal and human lesions were classified as either fatty streaks or fibrotic plaque. When compared to conventional spin-echo images, fat suppression by CSI substantially improved the measured contrast-to-noise ratio between plaque and vessel lumen, and enhanced its discrimination from periadventitial fat. In contrast, water suppression eliminated visualization of plaque due to the negligible amount of isotropic (liquid-like) signal from the immobilized lesion lipids. Magnetic resonance spectroscopy corroborated the CSI results by demonstrating broad, ill-defined fat resonances characteristic of nonmobile lipids in both human and rabbit atherosclerotic lesions. These findings indicate that in vivo MRI of plaque is technically feasible and can be markedly improved using chemical shift imaging.

Efficacy of thrombolysis in infrainguinal bypass grafts.

The initial outcome of a consecutive series of 43 intra-arterial urokinase infusions for thrombosed infrainguinal grafts in 37 patients was analyzed. There was an 88% (38/43) technical success rate (complete clot lysis) and a 74% (32/43) clinical success rate. Complications occurred in 10 patients (23%) and were related to bleeding in four patients (9%). Patient age, graft age, location, material, and the duration of occlusion did not significantly influence the initial outcome, although there was a trend toward a higher bleeding complication rate among grafts less than or equal to 1 month of age at the time of thrombolysis. A second group of 43 infrainguinal grafts successfully recanalized using regional infusions of thrombolytic agents were followed for long-term patency. This group included 32 grafts successfully treated with urokinase and 11 grafts recanalized with streptokinase. By life-table analysis there was a 55.6% 1-year patency, which fell to 42.4% at 4 years. Vein grafts had significantly (p = 0.01) better long-term patency than prosthetic grafts (69.3% versus 28.6% at 30 months). Grafts with flow-limiting lesions identified and corrected by angioplasty or surgery also had significantly (p = 0.01) better long-term patency than those without such lesions (79.0% versus 9.8% at 2 years). Based on the results of our study compared with a survey of long-term results following secondary surgical procedures for thrombosed infrainguinal grafts, thrombolysis can be recommended in several circumstances. Thrombolysis is indicated for thrombosed vein grafts or when thrombus is present in distal runoff vessels. Thrombosed prosthetic grafts should be replaced by autogenous vein grafts whenever possible.(ABSTRACT TRUNCATED AT 250 WORDS)

Airway compromise after carotid surgery in patients with cervical irradiation.

Symptomatic carotid atherosclerotic disease occurring as a result of cervical irradiation often requires surgical intervention. Airway obstruction is an uncommon problem after most carotid surgery and has not been described for patients with cervical irradiation. Airway obstruction developed after two of five carotid endarterectomy procedures in previously irradiated necks requiring emergency tracheostomy or reintubation. Mechanisms of obstruction included endotracheal tube trauma to the fixed irradiated vocal cords and laryngeal edema caused by surgical dissection in an irradiated field. In addition, one patient in our series demonstrated hypercarbia as a result of bilateral carotid body ablation, a process known to impair the ventilatory response to hypoxia. An increased risk of airway obstruction after carotid surgery exists in patients with prior cervical irradiation. Preventive methods include the use of perioperative steroids and either carotid surgery with local anesthesia or bronchoscopic vocal cord visualization and intubation.

Intravenous labetalol for the treatment of hypertension after carotid endarterectomy.

Hypertension after carotid endarterectomy has a variable incidence ranging up to 56%. Blood pressure (BP) control is essential due to possible increased risk of morbidity from neurologic deficits or cardiovascular complications. This study evaluated intravenous labetalol for control of hypertension after carotid endarterectomy. Sixty ASA II-IV patients were studied; 20 developed BP high enough for treatment with labetalol. The anesthetic technique was standardized. Labetalol was administered at the conclusion of surgery as a 20-mg bolus over two minutes followed by 40 mg every 10 minutes until the desired BP was achieved (BP less than or equal to 10% above average preoperative BP or less than 150 mmHg, systolic) or 300 mg had been given. The mean total dose of labetalol was 42.0 +/- 33.0 mg (mean +/- SD) and mean time to reach the desired BP was 16.2 +/- 21.4 minutes. Systolic, diastolic, mean arterial pressure and heart rate significantly decreased after labetalol treatment and remained so for the remainder of the 180-minute study period. There was no hypotension, bradycardia, evidence of myocardial ischemia or central nervous system dysfunction present with labetalol treatment. Blood samples were obtained for determination of plasma renin activity, epinephrine, and norepinephrine in 10 patients who developed hypertension and received labetalol, and 10 patients who did not develop hypertension. In the patients developing hypertension, there was a significant elevation in epinephrine just before treatment, that decreased by 30 minutes after treatment. Norepinephrine levels became significantly elevated five minutes after labetalol treatment in the group with hypertension and remained elevated for 120 minutes. Concomitantly, there was a significantly lower plasma renin activity seen in this group.(ABSTRACT TRUNCATED AT 250 WORDS)

Pseudoaneurysm of the ascending aorta following cardiac surgery.

Pseudoaneurysm of the ascending aorta is an unusual and potentially fatal complication of cardiovascular surgery. Most pseudoaneurysms are associated with aortic valve or coronary artery bypass graft surgery and are often mycotic in origin. Chest roentgenography and aortography have been the principle methods of diagnosis. Recently, contrast enhanced computed tomography (CT) has proven to be a useful means of diagnosis, providing a less invasive method of distinguishing pseudoaneurysm from other causes of fever and mediastinal widening in the postoperative cardiovascular patient. Thirty one cases of postoperative pseudoaneurysm of the ascending aorta occurring since 1963 are reviewed, including seven cases from our experience.

The value of intraoperative EEG monitoring during carotid endarterectomy.

Since controversy continues concerning the value of routine electroencephalographic (EEG) monitoring and selective carotid bypass shunting, we reviewed the neurological morbidity and mortality following elective carotid endarterectomy in 172 patients with symptomatic carotid occlusive disease. The use of EEG monitoring and selective shunting was associated with a reduction in the frequency of carotid shunts (49 to 12%) and a decline in combined major neurological morbidity and mortality (2.3 to 1.1%). We conclude that the routine use of intraoperative EEG monitoring is a valuable procedure, particularly in patients at high risk for perioperative neurological complications.

Surgically treatable lesions of the extracranial circulation, including the vertebral artery.

Stroke is the third most common cause of death in the United States, and 50 per cent of sources arise in the extracranial carotid arteries. Well-performed vascular surgery provides a low-risk approach in preventing this devastating event if these sources can be identified before the stroke occurs. An awareness of the patient at risk, an appreciation of the type and location of the causative lesions, and a timely diagnosis offer the best chance for success.

Ruptured abdominal aortic aneurysm with horseshoe kidney.

A case of ruptured abdominal aortic aneurysm associated with horseshoe kidney is presented. Two aspects of the operation are discussed: the vascular supply to the kidney and isthmus and the division of the isthmus. It is important in handling these cases either on an emergency basis or electively to be aware of the various vascular anomalies.

Preoperative embolization of retroperitoneal hemangiopericytomas as an aid in their removal.

The first reported cases of preoperatively embolized hemangiopericytomas are presented. Both lesions presented in the retroperitoneum where most lesions are now considered to be malignant. In the past, the highly vascular nature of these tumors has made resection in these areas difficult. Since the angiographic picture of hemangiopericytomas is now thought to be specific, it became feasible to add preoperative embolization to the overall management of these cases. In the first case, the diagnosis had been established 15 years previously. When first seen at Thomas Jefferson University Hospital, extensive bone destruction of the sacrum and lumbar vertebrae were present. Preoperative Gelfoam embolization aided in the palliative debulking of the tumor at operation. With this experience, preoperative embolization became part of the management in the second case and aided in the complete surgical removal of the tumor. Radiation therapy in the dosage of 5000 rad was given postoperatively in this case and should also be part of the treatment plan for these lesions.

Clinical aspects of persistent sciatic artery: report of two cases and review of the literature.

The sciatic artery is the principal blood supply to the lower extremity in the human embryo prior to the development of the femoral artery. Persistence of the sciatic artery in the adult is a rare albeit well documented anomaly with at least 29 cases reported in the world's literature and two additional cases presented here. The persistent sciatic artery is a branch of the internal iliac artery. It leaves the pelvis in close proximity with the sciatic nerve and is continuous with the popliteal artery. The superficial femoral artery usually is present and hypoplastic and only sends collaterals to the popliteal artery. Diagnosis of a patent sciatic artery is suggested by auscultation with a Doppler ultrasound and confirmed by autography. Obstruction and/or aneurysms of the sciatic artery should be treated with a femoral to popliteal or other distal artery bypass and ligation of the aneurysm if one is present.

Isolated massive chylopericardium. Complication of open heart surgery for aortic valve replacement.

Chylopericardium following open-heart surgery for aortic valve replacement in a 53-year-old woman is described. Five weeks after surgery, the chylous pericardial effusion was detected when the patient developed recurrent chest pain and cardiomegaly. Treatment included drainage of the fluid and partial pericardiectomy. No recurrence of the chylopericardium was observed in this patient up to 14 months after surgery.