Manel Matas

Transcranial Doppler Monitoring of Transcervical Carotid Stenting With Flow Reversal Protection A Novel Carotid Revascularization Technique

Background and Purpose— Transfemoral carotid stenting, despite becoming very frequent, has some limitations such as difficult groin access in few patients, lack of distal protection during filter placement, or embolization despite protection. Transcervical stenting (TCS) is a novel technique during which a common carotid to jugular vein shunt is placed creating a protective reversal flow in the internal carotid artery after proximal common carotid artery (CCA) clamping. We aim to study, with transcranial Doppler (TCD), cerebral flow changes and microemboli detection during transcervical stenting. Methods— From September 2005 to March 2006, of 65 consecutive patients eligible for carotid revascularization, 23 were considered high risk (sapphire criteria) and underwent TCS. Neurologic examination was performed before and after the procedure by a neurologist and a preprocedure vascular reactivity TCD examination was done in all patients. Results— After CCA clamping, flow inversion was observed in the anterior cerebral artery, supplying blood to the middle cerebral artery (MCA) and internal carotid artery (reversal). TCD did not detect any air/solid emboli during stent deployment and angioplasty confirming the reversal flow protection hypothesis. Mean reversal flow time was 15.4 minutes; in all cases, substantial MCA flow was present during CCA clamping (initial mean velocity 30 cm/s), and a slow gradual increase was observed traducing collateral flow recruitment (mean velocity after 5 minutes 36 cm/s, P<0.001). Flow increase was observed in all patients except in those with preprocedural exhausted ipsilateral vascular reactivity (16% versus 2%, P=0.036). The only in-procedure complication was one transient ischemic attack. After CCA unclamping, normal antegrade flow was restored in anterior cerebral artery and mean final MCA velocity increased 16% according to preprocedure flow. Conclusions— TCS with protective internal carotid artery flow reversal can eliminate showers of micoremboli during stent deployment making it a promising carotid revascularization technique in high-risk patients with carotid stenosis.

Intra-arterial administration of microbubbles and continuous 2-MHz ultrasound insonation to enhance intra-arterial thrombolysis.

Microbubbles (MB) and ultrasound have been shown to enhance thrombolysis. We sought to evaluate safety and efficacy on middle cerebral artery (MCA) recanalization of local MB administration during intra‐arterial (IA) thrombolysis and continuous transcranial Doppler (TCD) monitoring.

Endovascular Treatment of Traumatic Thoracic Aortic Injuries: Short- and Medium-term Follow-up

BACKGROUND Successful thoracic endovascular aortic repair (TEVAR) with low rates of complications has been referred to in the treatment of traumatic thoracic aortic injuries; however, we still do not know the long-term behavior. In this series, short- and intermediate-term results of TEVAR of traumatic aortic injuries are analyzed. METHODS The clinical charts and courses of 20 patients (mean age, 31.8 years; age range, 15-65 years; 14 [70%] men) with traumatic thoracic aortic injuries treated with TEVAR were retrospectively reviewed. Mean delay from trauma to intervention was 15 days (range, 0-180 days). RESULTS The initial success rate was 100%, with no deaths or intraoperative leaks, although in 4 (20%) patients, injuries were repaired in the arterial access site. The mean postoperative follow-up was 43.53 months (range, 5.5-108.0 months). Four (20%) patients required reintervention: 2 postoperative revascularizations of the left subclavian artery (20% of the patients in whom the ostium was intentionally occluded) and 2 aortic reinterventions (endovascular treatment of a collapsed stent graft and open repair after thrombosis of another stent graft). All reinterventions were successfully performed and no additional complications were registered during follow-up. Asymptomatic findings related to the stent graft included lack of proximal device-wall apposition in 8 patients (40%), intragraft mural thrombus formation during the first 6 months in 7 patients (35%), and an asymptomatic fracture of the longitudinal reinforcing bar of the stent graft 4 years later in 1 patient (5%). CONCLUSION Although not completely exempt of complications, TEVAR provides a reliable method for the treatment of traumatic thoracic aortic injuries with good results in the short- and medium-term follow-up. All complications have been treated successfully. Long-term evolution of lack of proximal device-wall apposition and intragraft mural thrombus formation should be closely monitored to prevent long-term complications.

Buying time for recanalization in acute stroke: arterial blood infusion beyond the occluding clot as a neuroprotective strategy.

Acute ischemic stroke treatment is meant to induce early reperfusion before ischemic lesion becomes definitive; unfortunately, in many cases, recanalization occurs too late. We present a case in which oxygenated blood was perfused through the occluding clot during intra‐arterial (IA) thrombolysis to anticipate reperfusion.

Incidence and Evolution of Mural Thrombus in Abdominal Aortic Endografts

BACKGROUND The aims of this study were to analyze the predictive factors for intragraft mural thrombus formation and evolution during follow-up after endovascular treatment of abdominal aortic aneurysms and to evaluate its relationship with the subsequent appearance of complications. METHODS A retrospective study was performed by selecting those patients who underwent endovascular repair of an abdominal aortoiliac aneurysm between June 1998 and September 2004, with a minimum follow-up of 24 months. Preoperative clinical data, anatomical characteristics of the aneurysm, and endograft type were analyzed. In addition, clinical evaluation and abdominal computed tomography angiography (CT scans) performed at 1, 6, 12, and 24 months after the surgery were reviewed. RESULTS Eighty-nine patients were submitted for endovascular aneurysm repair in this period, and 75 completed the 24-month follow-up. Eighteen patients developed intragraft mural thrombus (24% incidence), 13 (72.2%) appearing at 1 month of follow-up, and up to 16 (88.9%) appearing during the first 6 months. Logistic regression analysis showed that the lumen percentage of mural thrombus in the native aorta and the use of aortouniiliac endografts were independent predictors of intragraft mural thrombus formation (odds ratio, 1.065; 95% confidence interval, 1.022-1.110, and odds ratio, 8.014; 95% confidence interval, 1.598-40.181, respectively). No spontaneous regression of the thrombus was observed. The area of intragraft mural thrombus had increased at 12 and 18-24 months after their diagnosis (Wilcoxon signed rank test, p = 0.028 and 0.028, respectively). The presence of intragraft mural thrombus was associated with a greater tendency to endograft body or branch occlusion (5 of 18 cases with intragraft mural thrombus (27.8%) versus 1 of 57 cases without it (1.8%), (p = 0.003). CONCLUSION Intragraft formation of mural thrombus is a common finding during the follow-up of abdominal aortic endografts, particularly in aneurysms with large mural thrombus of the native aorta, and is associated with the use of aortouniiliac endografts. The area occupied by the mural thrombus was shown to gradually increase during follow-up and was associated with a greater tendency for endograft occlusion.

Late thrombosis of a thoracic aorta stent graft: Therapeutic management

The case of a 17-year-old adolescent boy with severe polytrauma is reported. Among other injuries, he presented with aortic rupture distal to the origin of the subclavian artery with no bleeding into the mediastinum. The lesion was repaired by placement of a Cook TX2 endovascular graft (Cook Incorporated, Bloomington, Ind). One year later, he was hospitalized with acute heart failure. Computed tomography angiography showed nearly complete stent graft occlusion and no evidence of altered integrity of the device. A right axillofemoral bypass was performed, allowing conversion to successful definitive repair consisting of an extra-anatomic bypass from the ascending aorta to the supraceliac abdominal aorta.

Compressive Symptoms Due to Thrombosed or Hypertrophic Collateral Circulation in Infrarenal Inferior Vena Cava Agenesis

Agenesis of the infrarenal segment of inferior vena cava is an uncommon and often asymptomatic congenital abnormality with an approximate incidence of 0.005-1% in the general population. Presentation of this condition as deep venous thrombosis associated with symptoms secondary to thrombosis or hypertrophy of collateral vessels is a rare clinical form. Two cases of this rare form are described, and an analysis of the related literature is presented. The first case was that of a 35-year-old man with symptoms of acute obstructive pyelonephritis with no apparent cause and swelling of the lower limb. The second case involved a 30-year-old man with lower limb swelling associated with paresthesia and motor deficit. Both patients were found to have infrarenal inferior vena cava agenesis associated with iliofemoral deep venous thrombosis and compression of anatomic structures by collateral vessels (ureteral compression due to thrombosis of an ectatic gonadal vein and L5 nerve root compression due to a hypertrophic epidural venous plexus). Patients were conservatively managed with anticoagulation therapy, with a favorable outcome and no recurrence in either case. In a young patient with iliac deep venous thrombosis of uncertain etiology, and particularly in those with atypical associated symptoms (mainly abdominal or neurologic), it is important to investigate congenital vena cava anomalies and carry out diagnostic imaging studies. Anticoagulation therapy is currently considered the best treatment option for this condition, but it should be individualized. The need for long-term anticoagulation should also be assessed in each case.

Innominate artery aneurysm with hemoptysis and airway compression in a patient with bovine aortic arch.

We present the case of a 63-year-old man with a bovine aortic arch variation, who presented episodes of mild hemoptysis secondary to a 4.5-cm (diameter) aneurysm of the innominate artery that compressed the trachea and obliterated the right subclavian artery. Surgery, performed through a median sternotomy, consisted of a bypass from the ascending aorta to both common carotid arteries using a Dacron graft, and exclusion of the aneurysm by ligature and direct thrombin injection. Computed tomography angiography at 30 days showed a patent bypass, successful aneurysm exclusion, and improvement of the tracheal compression. The patient is currently asymptomatic at 12 months following the procedure.