Carotid endarterectomy using a "home-constructed" shunt for patients intolerant to cross-clamping

Anticoagulation strategy in patients with atrial fibrillation after carotid endarterectomy

Aim: Carotid artery stenosis and atrial fibrillation are diseases of the aging patient population. Literature lacks precise anticoagulation treatment protocols for patients with atrial fibrillation following carotid endarterectomy. We present our experiences with anticoagulation strategy in this particular patient population. Patients and methods: Between June 2001-September 2017, 165 patients with chronic or paroxysmal atrial fibrillation out of 1594 cases from three different institutions whom received Coumadin and aspirin and required carotid endarterectomy were reviewed, respectively. Mean age was 63.4 ± 7.9 years. Male/female ratio was 102/63. There were 67 diabetic and 138 hypertensive cases. Results: Patients are followed a mean of 64.4 ± 16.9 months. Early mortality occurred in two patients due to intracranial bleeding and heart failure. Another patient was lost due to intracerebral hemorrhage and 16 other patients died due to various causes in the late follow-up. Three patients required exploration against bleeding. Conclusion: Combination of warfarin with an aim to keep the INR value between 2 and 3, and aspirin at a dosage of 100 mg per day seemed feasible and in our modest patient cohort. Further studies including multicenter larger data are warranted in order to establish a precise anticoagulation treatment protocol for patients with atrial fibrillation after carotid endarterectomy.

Determination of Ultrastructural Properties of Human Carotid Atherosclerotic Plaques by Scanning Acoustic Microscopy, Micro-Computer Tomography, Scanning Electron Microscopy and Energy Dispersive X-Ray Spectroscopy

Microcalcification is the precursor of vulnerability of plaques in humans. Visualization of such small structures in vivo with high spatial resolution is an unsolved issue. The goal of this study is to evaluate the potential of scanning acoustic microscopy (SAM) in the determination of atherosclerotic plaques with calcifications by validating this technique with micro-computer tomography (micro-CT), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). The fibrocalcific plaques were obtained from 12 different patients and initially examined with micro-CT. The images exhibited calcifications within these plaques. For imaging with SAM, approximately 5 μm thick slices were prepared. Sound speed values within calcified regions were measured to be greater than the ones in collagen-rich regions. These fibrocalcific plaques were also examined with SEM and EDS revealing collagen and calcium deposition within these samples. The consistency of the results obtained by all of the modalities involved in our study is an indication of the potential of SAM as a clinical tool for the diagnosis of vulnerable plaques.

The importance of internal carotid artery occlusion tolerance test in carotid endarterectomy under locoregional anesthesia

BACKGROUNDS

Carotid endarterectomy is considered a safe and effective method for preventing stroke in the short and long term in patients with severe carotid stenosis. The internal carotid artery (ICA) occlusion tolerance test was performed to evaluate cerebral tolerance during temporary carotid occlusion, defined as the capacity of the cerebral hemisphere to maintain adequate cerebral blood flow during occlusion of the ICA. Thus, the aim of the present study is to determine the importance of this test in patients undergoing carotid endarterectomy.

METHODS

From August 2008 to May 2015, 115 consecutive patients (39 female, 77 male) were referred for carotid endarterectomy at the Santa Casa de Belo Horizonte by the main author.

RESULTS

Of the 115 patients who participated in the study, 107 were submitted to carotid endarterectomy. Morbi-mortality was 2.7 %. The presence of deficits during the ICA occlusion tolerance test in less than 30 s was associated with the presence of complications. Among the 104 patients who showed no deficits during the test, only one case (0.9 %) presented complications, while among the three cases that showed deficits during the test and who were submitted to carotid endarterectomy, two cases presented complications (p < 0.0001).

CONCLUSIONS

The carotid endarterectomy under locoregional anesthesia is a safe surgical procedure. The internal carotid artery occlusion tolerance test can help identify high-risk patients who have been assigned this treatment.

Locoregional Anesthesia for Carotid Endarterectomy: Identification of Patients with Intolerance to Cross-Clamping

OBJECTIVE

During carotid endarterectomy (CEA), carotid cross-clamping is performed to allow for artery incision and plaque removal. A small subgroup of patients can tolerate carotid occlusion for only a few seconds, if at all, without presenting neurologic deficit. These patients are described as having ''cross-clamp intolerance.'' The purpose of this study was to demonstrate the safety of locoregional anesthesia in identifying patients with cross-clamp intolerance and factors associated with this condition.

METHODS

From August 2008 to May 2010, 115 consecutive patients were submitted to CEA under locoregional anesthesia at the Santa Casa de Belo Horizonte; the procedure was performed by the main author. Patients who showed intolerance to internal carotid artery (ICA) occlusion for <30 seconds were considered to have cross-clamp intolerance.

RESULTS

Among the 115 participating patients, 9.6% (11 patients) showed intolerance to ICA occlusion and developed deficits in <30 seconds (i.e., these patients presented cross-clamp intolerance). The factor that was associated with cross-clamp intolerance was the mean degree of contralateral carotid stenosis, which was 57.5% for those who presented intolerance and 27.8% for those who tolerated ICA occlusion.

CONCLUSION

Locoregional anesthesia is a safe method for identifying patients with cross-clamp intolerance. Patients with cross-clamp intolerance present contralateral stenosis that is greater on average than patients who readily tolerate carotid artery occlusion.

Cerebral protection with a crossover external carotid artery bypass during arch debranching

Endovascular stent graft repair of the thoracic aorta sometimes requires debranching of the aortic arch and reimplantation of the left common carotid and left subclavian arteries to the brachiocephalic trunk. Cerebral protection has utmost importance during such a procedure. The surgical technique detailed here offers pulsatile flow inside the internal carotid arteries despite proximal clamping of the common carotid arteries throughout the whole procedure.