Rupture of the vein patch: a rare complication of carotid endarterectomy.

Vein patch closure after carotid endarterectomy has been used to reduce the incidence of residual and recurrent stenosis at the carotid bifurcation. A rare but potential serious complication is rupture of the vein patch during the early postoperative period. In our experience of 2359 carotid operations performed from 1962 through 1986, saphenous vein was used for closure in 2275 (96.5%) operations. In three patients out of 75 in whom the vein patch had been harvested from the ankle, rupture of the patch occurred 2 to 5 days after uneventful carotid surgery. At emergency reoperation, the central portion of the vein was necrotic, with no evidence of infection. In each case the carotid artery was closed again with fresh thigh saphenous vein, and recovery was uneventful. The use of ankle vein was discontinued in December 1983 in favor of groin saphenous vein, and similar complications have not occurred in more than 600 carotid endarterectomies performed since. Early noninfectious ruptures of the saphenous vein patches have been mentioned in other reported series of carotid operations and have often been related to the use of ankle vein, but they remain unexplained.

Beta blockade to decrease silent myocardial ischemia during peripheral vascular surgery.

The incidence and duration of intraoperative silent myocardial ischemia have been shown to be significantly correlated with the incidence of perioperative myocardial infarction in patients undergoing peripheral vascular surgery. To assess the effectiveness of intraoperative beta blockade in limiting such silent myocardial ischemia, a group of 48 patients was treated with oral metoprolol immediately prior to peripheral vascular surgery. The total duration of intraoperative silent myocardial ischemia, the percentage of intraoperative time silent myocardial ischemia was present, the number of intraoperative episodes of silent myocardial ischemia, and the intraoperative heart rate in the treated patients were compared with those in 152 similar but untreated peripheral vascular surgery patients. The patients treated with oral metoprolol had significantly less intraoperative silent ischemia with respect to relative duration and frequency of episodes, a significantly lower intraoperative heart rate, and less intraoperative silent myocardial ischemia in terms of total absolute duration. These results suggest that beta-adrenergic activation may play a major role in the pathogenesis of silent myocardial ischemia during peripheral vascular surgery.

[Need for surgery in asymptomatic carotid stenosis]. / Operationsbedürftigkeit asymptomatischer Karotisstenosen.

1. Asymptomatic carotid stenosis up to 80% do not require prophylactic surgery, but should be followed non-infasively. 2. Stenoses of 80-99% are associated with a significant incidence of stroke which is estimated to be 4-10%/year. 3. Occlusion is considered to be an unfavorable end point, since the risk of stroke remains higher than those with patent arteries. 4. The role of carotid endarterectomy is related to the stroke morbidity and mortality of the procedure. To show significant benefits of surgical therapy during the first two years, it is necessary to have a stroke/death rate of less than 3%.

Limb salvage with microvascular free flap reconstruction using simultaneous polytetrafluoroethylene graft for inflow.

Microvascular free flaps have been successfully used to cover defects of the lower extremity. In patients with peripheral vascular disease and lower extremity defects, revascularization with in situ or reversed saphenous vein bypass graft combined with microvascular tissue transfer can salvage a limb that would otherwise be amputated. However, some of these patients may not have autologous vein available for the bypass procedure. We present a case of a 69-year-old man who underwent revascularization with a long polytetrafluoroethylene (PTFE) graft and a simultaneous microvascular free flap reconstruction using the PTFE graft as the inflow. The patient had undergone coronary artery bypass graft with saphenous vein and experienced a nonhealing wound of the distal saphenous vein harvest site and exposure of 8 cm of tibia. Angiogram revealed a significant stenosis of the common iliac artery, occluded superficial femoral artery, faint filling of the profunda femoris artery, and a faintly reconstituted posterior tibial artery. Because the patient had no available saphenous vein for bypass, he underwent an axillary-profunda and profunda-posterior tibial artery bypass with PTFE. A rectus abdominus microvascular free flap with direct anastomosis of the inferior epigastric artery to the PTFE was used to cover the exposed bone. The patient currently ambulates without difficulty. Limb salvage using bypass with PTFE combined with simultaneous microvascular free flap reconstruction is possible in selected patients.

Should proximal saphenous vein be used for carotid patch angioplasty: a clinical study of the need for vein in subsequent operations.

Reluctance to use saphenous vein (SV) for patch closure of the carotid arteriotomy is due in part to the concern of vascular surgeons that the SV should be preserved for possible future coronary or lower extremity reconstruction. Even among those who favour vein patch closure of the arteriotomy for improved immediate and late results, an effort has been made to use the ankle portion of the SV, preserving the upper, larger segment for later surgery. Recent reports of rupture of the patches formed from ankle SV and a study showing a decrease in strength of the ankle segment of vein, raised the question of the importance of trying to preserve the proximal SV and the impact of use of this segment in those patients requiring secondary vascular procedures. We reviewed 134 consecutive carotid patients from 1981 who had proximal SV harvested for patch angioplasty. Of those 122 were available (mean 44.9 months). Thirteen had secondary vascular procedures. Adequate saphenous vein was available in twelve. We conclude from this study that (1) less than 15% of patients undergoing carotid surgery will require a secondary vascular surgery within 5 years and (2) harvesting SV from the thigh rarely compromises future revascularisation.

Is duplex scanning sufficient evaluation before carotid endarterectomy?

Recent reports have suggested that cerebral angiography may not be necessary before carotid endarterectomy is performed in selected patients. To determine if arteriography provides additional information that might influence the decision to operate or the conduct of the operation, a retrospective review was performed of 100 consecutive patients undergoing cerebral angiography and carotid duplex scanning. Eighty of the 100 patients subsequently underwent carotid endarterectomy for neurologic symptoms or asymptomatic stenosis greater than 80%. Among the 20 patients not operated on, three would have undergone unnecessary surgery for mistaken diagnoses had the arteriogram not been obtained. Two other patients in this group of 20 would have had carotid endarterectomy for asymptomatic stenosis in the presence of an equally stenotic tandem lesion. Among the 80 patients operated on, an additional three had the operative procedure altered because arteriographic studies revealed pathologic findings outside the area of duplex scan examination. Thus the use of arteriography altered the management of eight (8%) patients in this group of 100.

Vertebral artery angioplasty in patients younger than 55 years: long-term follow-up.

Since 1964 we have performed 136 vertebral artery reconstructions representing 4% of all operations on extracranial cerebral arteries by our staff. Fifteen of our patients were under age 55 years and had symptoms of dizziness, bilateral visual disturbances, ataxia, presyncopal episodes, and occasionally localized extremity weakness. Dizziness, often severe and incapacitating, has been the most common and consistent symptom. The diagnosis of vertebral artery lesions was made using aortic arch four-vessel cerebral arteriography. Operations were performed for severely obstructing bilateral vertebral artery lesions and included only unilateral vertebral vein patch angioplasty with or without suture plication of the artery in 13 patients. Unilateral carotid vertebral bypass was performed in one patient and unilateral vertebral reimplantation to the carotid in another. Follow-up averaged 8.9 years, ranging from ten months to 20 years. Eleven of 15 patients have remained asymptomatic and without strokes. Recurrent dizziness was present in three, two of whom had vertebral arteriography showing patent vertebral reconstructions. Another had a stroke related to the anterior circulation in follow-up at nine years. Atherosclerotic obstruction of vertebral arteries does occur in patients in the preatherosclerotic age group. Even atypical symptoms suggestive of vertebrobasilar insufficiency may be associated with isolated correctable bilateral flow-impeding vertebral lesions. These symptoms warrant evaluation with cardiac neurological and cerebrovascular studies. Vertebral angioplasty relieves symptoms and the incidence of stroke during follow-up is low.

Intracranial hemorrhage after carotid endarterectomy.

Among 1500 carotid endarterectomies performed between 1975 and 1984, 11 ipsilateral intracranial hemorrhages (IH) occurred between the first and tenth postoperative days for an incidence of 0.7%. The mortality rate among these patients was 36%. The only recognizable predisposing factor was relief of high-grade carotid stenosis (greater than 90%) whereas other factors such as age (58 to 81 years), preoperative hypertension (systolic blood pressure 120 to 160 mm Hg), preoperative head CT scans showing recent infarction (only one in five positive), and preoperative cerebral infarction (only 1 of 11 patients) did not play a role. All patients had normal coagulation studies. No patient required a shunt because all tolerated cross-clamping of the carotid artery. Postoperative systolic blood pressures were 200 to 240 mm Hg in 6 of 11 patients. The time of occurrence of IH extended from the immediate postoperative period to the tenth postoperative day (mean interval 3.3 days). Treatment consisted of craniotomy in five patients; four survived and one recovered completely. Of the six patients treated nonoperatively, three survived and two completely recovered. IH shares equal incidence with recurrent thrombosis, cross-clamping ischemia, and embolization as a cause of perioperative stroke. Although all except IH can be prevented by current practice, the means of preventing IH are not apparent; however, careful monitoring of blood pressure to prevent uncontrolled hypertension deserves consideration.

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.

Causes of the increased stroke rate after carotid endarterectomy in patients with previous strokes.

Patients who have sustained a preoperative stroke are at increased risk for perioperative stroke after carotid endarterectomy. At our institution this risk was recently shown to be increased two-to threefold. The purpose of this study was to investigate the reasons for the increased surgical risk in these patients. Records of 606 patients undergoing 704 consecutive carotid endarterectomies from 1988 through 1993 were reviewed. Patients who suffered preoperative strokes (n = 183) were compared to those who were either asymptomatic or experienced only transient ischemic attacks (TIAs) preoperatively (n = 423). Of the 183 patients who had suffered preoperative strokes, eight patients who experienced perioperative strokes after endarterectomy were compared with 175 who successfully underwent surgery. Patients with a prior stroke had an increased perioperative stroke rate (4.4% versus 1.2%, p = 0.01). They had a significantly higher incidence of hypertension (62.6% versus 47.9%, p < 0.001), cardiac disease (54.7% versus 40.7%, p = 0.001), and positive smoking history (52% versus 40.6%, p = 0.01) than did the asymptomatic/TIA patients. The presence of contralateral total occlusion was also significantly increased (22% versus 10.3%, p < 0.001). Although not statistically significant due to the overall small number of patients who sustained perioperative strokes, the preoperative stroke patients who sustained perioperative strokes had a higher incidence of hypertension (87.5% versus 61.5%) and contralateral total occlusion (37.5% versus 21.3%) than did those who successfully underwent surgery. Patients with both a prior stroke and contralateral total occlusion had a 7.5% perioperative stroke rate. Patients with both a prior stroke and hypertension had a 6.1% perioperative stroke rate. The perioperative strokes in patients with prior strokes were not related to the severity of the prior stroke, the interval between the stroke and surgery, the use of a shunt, or the type of anesthesia employed. Patients who have sustained preoperative strokes have a higher incidence of significant medical illnesses and overall cerebrovascular disease. Hypertension and total occlusion of the contralateral carotid artery appear to be particularly poor prognostic indicators of outcome after endarterectomy in these patients. Patients who have sustained preoperative strokes may be more likely to display clinical neurologic symptoms in response to any form of cerebral ischemia. In this higher risk subgroup, intraoperative and surgeon-dependent factors appear to play less of a role.

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.

Successful treatment of postpartum shock caused by amniotic fluid embolism with cardiopulmonary bypass and pulmonary artery thromboembolectomy.

We report the successful treatment of a moribund patient as a result of amniotic fluid embolism with cardiopulmonary bypass and open pulmonary artery thromboembolectomy. Review of the literature indicates that this is the first reported case of treatment of amniotic fluid embolism with cardiopulmonary bypass and pulmonary thromboembolectomy.

Redo endarterectomy for recurrent carotid artery stenosis.

From a registry of 2406 carotid endarterectomies performed on 1818 patients over a 19-year period, 29 patients (1.6%) underwent reoperations for recurrent stenosis. Reoperations were performed for symptomatic stenosis for 23 and asymptomatic greater than 80% stenosis for six patients. Compared to the entire series, there was no difference in the incidence of restenosis for men and women. The pathologic findings were myointimal hyperplasia in 27%, atherosclerosis in 53%, thrombus with vessel dilatation in 17% and extrinsic scar in 3%. Redo endarterectomy with patch angioplasty was used for reconstruction in 27 patients and patch angioplasty alone in two. There were no operative deaths or strokes. Late follow-up (mean 50 months) revealed only one stroke and six other deaths. Although 21 (75%) were alive and stroke-free, follow-up studies suggest a high incidence (21%) of tertiary lesions among patients who have undergone redo endarterectomy for recurrent stenosis.

Differences in carotid shunt flow rates and implications for cerebral blood flow.

A wide variety of carotid shunts are available for use in extracranial carotid surgery. Since it is commonly assumed that when properly positioned all shunts are equal in ability to protect the brain from cerebral ischemia, the choice of shunt is usually based on handling characteristics. However, after an intraoperative stroke occurred in a patient, we compared shunt flow rates using a simple and reproducible method of measurement. A mock circuit was created using a saline-filled fluid reservoir connected to the particular shunt being tested via 1/2-inch tubing. Hydrostatic pressure across the shunt was varied by changing the height of the reservoir, and the flow was collected over 30-second intervals. Multiple flow rate measurements were performed for each shunt with pressure gradients varying from 25 to 150 cm H2O. The data show significant hemodynamic differences among commercially available carotid shunts. A pressure gradient of 75 cm H2O produced a 2.8-fold variation in the amount of fluid delivered by various shunts. Minimal cerebral blood flow requirements and the possibility of underperfusion require that the surgeon consider such data in choosing an appropriate carotid shunt.

The value of silent myocardial ischemia monitoring in the prediction of perioperative myocardial infarction in patients undergoing peripheral vascular surgery.

Real-time electrocardiographic monitoring for silent myocardial ischemia was performed on 200 patients undergoing peripheral vascular surgery to try to better define those at high risk of perioperative myocardial infarction. The patients were divided into those undergoing abdominal aortic aneurysm or lower extremity revascularization procedures (group I, n = 120) and those undergoing carotid artery endarterectomy (group II, n = 80). Silent ischemia was detected during the preoperative, intraoperative, or post-operative periods in 60.8% of group I and 67.5% of group II patients. Six group I and three group II patients suffered an acute perioperative myocardial infarction with two cardiac deaths. In both groups I and II a variety of parameters based on monitoring of silent myocardial ischemia were compared between the subgroups of patients who had myocardial infarction and those who did not. The results show that in both groups there was a significantly (p less than or equal to 0.05) greater total duration of perioperative ischemic time, total number of perioperative ischemic episodes, and total duration of perioperative ischemic time as a percent of total monitoring time in patients who suffered a perioperative myocardial infarction compared to those who did not. Multivariate logistic regression analysis of preoperative characteristics in all 200 patients showed the occurrence of preoperative silent myocardial ischemia and angina at rest to be the only significant predictors of perioperative myocardial infarction. Thus perioperative monitoring for silent myocardial ischemia might noninvasively identify those patients undergoing peripheral vascular surgery who are at increased risk for perioperative myocardial infarction, permitting implementation of timely preventive measures in selected patients.

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.

Gadolinium-enhanced 3D MRA of the aortic arch vessels in the detection of atherosclerotic cerebrovascular occlusive disease.

PURPOSE: Our goal was to evaluate non-breath-hold Gd-enhanced 3D MR angiography (MRA) for the detection of atherosclerotic occlusive disease of the aortic arch vessels and to compare image quality with two breath-hold techniques. METHOD: One hundred sixty consecutive patients with known or clinically suspected atherosclerotic cerebrovascular occlusive disease underwent Gd-enhanced 3D MRA of the aortic arch and great vessels. One hundred twenty-six examinations were performed with the body coil after infusion of 40 ml of Gd-DTPA; 89 of these were performed without breath-holding and 37 were acquired during suspended respiration. Thirty-four examinations were performed in a body phased-array coil with breath-holding, a timing examination, and 20 ml of contrast agent by manual (n = 17) or power (n = 17) injection. Images were evaluated for the presence of blurring and ghosting artifacts and venous enhancement. Of the 27 patients who underwent non-breath-hold MRI and digital subtraction angiography (DSA), two readers blinded to the DSA results retrospectively evaluated the MRA examinations for the presence of occlusive disease of the innominate, carotid, subclavian, and vertebral arteries. DSA correlation was not evaluated for the 71 breath-hold studies. RESULTS: Sensitivity and specificity for arch vessel occlusive disease with non-breath-hold MRA were 38 and 94% for Reader A and 38 and 95% for Reader B. Breath-holding significantly reduced blurring and ghosting artifacts (p < 0.001) when compared with non-breath-hold imaging, and use of 20 ml of contrast medium, with a timing examination, resulted in significantly less venous enhancement than seen with 40 ml (p < 0.001). CONCLUSION: Non-breath-hold Gd-enhanced 3D MRA is insensitive for detecting arch vessel occlusive disease. Breath-hold imaging, in conjunction with a timing examination and a lower dose of contrast agent, improves image quality, but further studies are needed to assess diagnostic accuracy.

Silent myocardial ischemia monitoring predicts late as well as perioperative cardiac events in patients undergoing vascular surgery.

In a previous study we have shown that perioperative monitoring for silent myocardial ischemia can noninvasively identify those patients undergoing peripheral vascular surgery who are at significantly increased risk for perioperative myocardial infarction. In the present study a group of 385 patients undergoing peripheral vascular surgery was studied long-term as well as short-term to determine whether perioperative monitoring for silent ischemia can identify those patients who are at significantly increased risk of late cardiac death or late cardiac complications as well as those patients at increased risk of perioperative myocardial infarction. All patients were monitored before, during, and after operation and were divided into two groups on the basis of results of monitoring: patients whose total duration of silent ischemia as a percentage of the total duration of perioperative monitoring was 1% or greater (group I, n = 120) and those for whom this value was less than 1% (group II, n = 265). Among patients in group I 13.3% (16 of 120) suffered a perioperative myocardial infarction in contrast to only 1.1% (3 of 265) patients in group II (p less than 0.001). Multivariate logistic regression analysis of preoperative and perioperative characteristics showed that the presence of a total perioperative percent time ischemic 1% or greater and age were the only significant predictors of perioperative myocardial infarction.(ABSTRACT TRUNCATED AT 250 WORDS)

Long-term follow-up of patients undergoing reoperation for recurrent carotid artery disease.

PURPOSE: We examined the perioperative course and long-term fate of individuals who required reoperation for recurrent carotid artery disease. METHODS: The records of 2289 patients undergoing 2961 consecutive operations during a 22-year period were reviewed. Forty-two patients (1.8%) who underwent reoperations were studied. Forty-seven redo carotid artery reconstructions were performed on these 42 patients for neurologic symptoms or asymptomatic high-grade stenosis. Long-term follow-up was obtained on 41 of 42 patients (mean 54 months; range 9 to 202 months). RESULTS: The forty-seven reoperations consisted of endarterectomy with patch angioplasty (n = 36), saphenous vein or polytetrafluoroethylene interposition graft (n = 7), or simply vein or polytetrafluoroethylene patch angioplasty (n = 4). There were no perioperative strokes or deaths. Three patients had perioperative transient ischemic attacks and two had cranial nerve injuries. The incidence of late failure after secondary surgery was 19.5% (8/41 patients). These failures consisted of one stroke, three transient ischemic attacks, and four asymptomatic occlusions. One tertiary carotid artery reconstruction was performed for a restenosis at the site of the secondary reconstruction. CONCLUSION: The factors responsible for the high incidence of late failures after secondary carotid artery reconstruction are unclear. Reoperation for recurrent carotid artery disease appears less durable than primary carotid endarterectomy. Close postoperative surveillance is recommended after carotid artery reoperation.