Pediatric renovascular hypertension: 132 primary and 30 secondary operations in 97 children

PURPOSE

This study was undertaken to characterize the contemporary surgical treatment of pediatric renovascular hypertension.

METHODS

A retrospective analysis was conducted of the clinical data of 97 consecutive pediatric patients (39 girls, 58 boys), aged from 3 months to 17 years, who underwent operation at the University of Michigan from 1963 to 2006. All but one patient had refractory hypertension not responsive to contemporary medical therapy. Developmental renal artery stenoses accounted for 80% of the renal artery disease, with inflammatory and other ill-defined stenoses encountered less frequently. Splanchnic arterial occlusive lesions affected 24% and abdominal aortic coarctations, 33%.

RESULTS

Primary renal artery operations were undertaken 132 times. Procedures included resection beyond the stenosis and implantation into the aorta in 49, renal artery in 7, or superior mesenteric artery in 3; aortorenal and iliorenal bypasses with vein or iliac artery grafts in 40; focal arterioplasty in 10; resection with reanastomosis in 4; operative dilation in 4; splenorenal bypass in 2; and primary nephrectomy in 13 when arterial reconstructions proved impossible. Bilateral renal operations were done in 34 children, and 17 underwent celiac or superior mesenteric arterial reconstructions, including 15 at the time of the renal operation. Thirty patients underwent abdominal aortic reconstructions with patch aortoplasty (n = 19) or thoracoabdominal bypass (n = 11). Twenty-five of the aortic procedures were performed coincidently with the renal operations. Thirty secondary renal artery procedures were done in 19 patients, including nine nephrectomies. Hypertension was cured in 68 children (70%), improved in 26 (27%), and was unchanged in three (3%). Follow-up averaged 4.2 years. No patients required dialysis, and there were no operative deaths.

CONCLUSION

Contemporary surgical treatment of pediatric renovascular hypertension emphasizes direct aortic implantation of the normal renal artery beyond its stenosis and single-staged concomitant splanchnic and aortic reconstructions when necessary. Benefits accompany carefully executed operative procedures in 97% of these children.

Advantages and indications of transcervical carotid artery stenting with carotid flow reversal

AIM

The aim of this Italian prospective registry was to evaluate the applicability and efficacy of the Mo.Ma Device (Invatec, Roncadelle, Italy) for the prevention of cerebral embolization during carotid artery stenting (CAS) in a real world population.

METHODS

In 4 Italian centers, 416 patients (300 men; mean age 71.6+/-9 years) between October 2001 and March 2005 were enrolled in a prospective registry. Two-hundred and sixty-four symptomatic (63.46%) with >50% diameter stenosis and 152 (36.54%) asymptomatic patients with >70% diameter stenosis were included. The Mo.Ma Proximal Flow Blockage Embolic Protection System was used to perform protected CAS, achieving cerebral protection by endovascular clamping of the common carotid artery (CCA) and of the external carotid artery (ECA).

RESULTS

Technical success, defined as the ability to establish protection with the Mo.Ma device and to deploy the stent, was achieved in 412 cases (99.03%). The mean duration of flow blockage was 4.91+/-1.1 min. Transient intolerances to flow blockage were observed in 24 patients (5.76%), but in all cases the procedure was successfully completed. No peri-procedural strokes and deaths were observed. Complications during hospitalization included 16 minor strokes (3.84%), 3 transient ischemic attacks (0.72%), 2 deaths (0.48%) and 1 major stroke (0.24%). This resulted in a cumulative rate at discharge of 4.56% all strokes and deaths, and of 0.72% major strokes and deaths. All the patients underwent thirty-day follow-up. At thirty-day follow-up, there were no deaths and no minor and major strokes, confirming the overall cumulative 4.56% incidence of all strokes and deaths rate, and of 0.72% rate of major strokes and deaths at follow up. In 245 cases (58.89%) there was macroscopic evidence of debris after filtration of the aspirated blood.

CONCLUSIONS

This Italian multicenter registry confirms and further supports the efficacy and applicability of the endovascular clamping concept with proximal flow blockage in a broad patient series. Results match favorably with current available studies on carotid stenting with cerebral protection.

Renal artery stenosis and aneurysms associated with neurofibromatosis

Renal artery lesions associated with neurofibromatosis may involve stenosis and aneurysm formation at all levels of the renal artery to the intraparenchymal branches, and usually are associated with hypertension. A 13-year-old boy with type I neurofibromatosis and severe hypertension presented with multiple aneurysms and multiple stenotic lesions in the renal artery and segmental arteries. The patient underwent ex-vivo renal artery repair with autologous hypogastric artery and autotransplantation to the iliac fossa and was clinically improved. The characteristic histologic findings are presented. A review of the recent literature comparing different treatment modalities for renovascular hypertension in children with neurofibromatosis suggests that surgery remains the best treatment alternative.

Endovascular Therapy for Tracheoinnominate Artery Fistula: A Temporizing Measure

Tracheoinnominate artery fistula remains an uncommon, highly fatal complication of tracheostomy and peritracheal pathology. Endovascular placement of a covered stent can provide control of the fistula. Depending on the conditions of the trachea and peritracheal tissues, the fistula may heal or the stent may become infected and/or further erode into the trachea. We report on a case of a patient with a tracheoinnominate artery fistula related to peritracheal tumor invasion, radiation therapy, and tracheostomy. The fistula was initially excluded with a covered stent, but a few weeks later hemoptysis recurred secondary to deep tracheal erosion by the covered stent.

Transcervical carotid artery angioplasty and stenting with carotid flow reversal: surgical technique

We have performed this technique in 40 patients with carotid artery stenosis. No deaths or strokes have occured. During the initial experience, one patient in whom flow reversal was not properly established sutained an hemispheric transient ischemic attack. Transcervical carotid artery balloon dilatation and stenting is feasible and safe. It establishes reliable cerebral protection before the carotid lesion is instrumented by reversing flow in the internal and external carotid arteries. It can be done under local anesthesia, and it avoids the potential limitations, complications, and additional cost of the transfemoral approach with protection devices.

Transcervical carotid stenting with internal carotid artery flow reversal: Feasibility and preliminary results

OBJECTIVE

Transfemoral carotid artery stenting (CAS), with or without distal protection, is associated with risk for cerebral and peripheral embolism and access site complications. To establish cerebral protection before crossing the carotid lesion and to avert transfemoral access complications, the present study was undertaken to evaluate a transcervical approach for CAS with carotid flow reversal for cerebral protection.

METHODS

Fifty patients underwent CAS through a transcervical approach. All patients with symptoms had greater than 60% internal carotid artery (ICA) stenosis, and all patients without symptoms had greater than 80% ICA stenosis. Twenty-one patients (42%) had symptomatic disease or ipsilateral stroke, and 8 patients (16%) had contralateral stroke. Four patients (8%) had recurrent stenosis, 7 patients (14%) had contralateral ICA occlusion, and 1 patient (2%) had undergone previous neck radiation. Twenty-seven procedures (54%) were performed with local anesthesia, and 23 (46%) with general anesthesia. Using a cervical cutdown, flow was reversed in the ICA by occluding the common carotid artery and establishing a carotid-jugular vein fistula. Pre-dilation was selective, and 8-mm to 10-mm self-expanding stents were deployed and post-dilated with 5-mm to 6-mm balloons in all cases.

RESULTS

The procedure was technically successful in all patients, without significant residual stenoses. No strokes or deaths occurred. There was 1 wound complication (2%). All patients were discharged within 2 days of surgery. Mean flow reversal time was 21.4 minutes (range, 9-50 minutes). Carotid flow reversal was not tolerated in 2 patients (4%). Early in the experience, carotid flow reversal was not possible in 1 patient, and there were 1 major and 3 minor common carotid artery dissections, which resolved after stent placement. One intraoperative transient ischemic attack (2%) occurred in 1 patient in whom carotid flow was not reversed, and 1 patient with a contralateral ICA occlusion had a contralateral transient ischemic attack. At 1 to 12 months of follow-up, all patients remained asymptomatic, and all but 1 stent remained patent.

CONCLUSION

Transcervical CAS with carotid flow reversal is feasible and safe. It can be done with the patient under local anesthesia, averts the complications of the transfemoral approach, and eliminates the increased complexity and cost of cerebral protection devices. Transcervical CAS is feasible when the transfemoral route is impossible or contraindicated, and may be the procedure of choice in a subset of patients in whom carotid stenting is indicated.

Carotid angioplasty with internal carotid artery flow reversal is well tolerated in the awake patient

OBJECTIVE

The purpose of this study was to evaluate the neurologic tolerance and changes in ipsilateral hemispheric oxygen saturation during transcervical carotid artery stenting with internal carotid artery (ICA) flow reversal for embolic protection.

PATIENTS AND METHODS

This was a prospective study of 10 patients (mean age 68 years) undergoing transcervical carotid angioplasty and stenting. All ICA stenoses were greater that 70%. Seven patients had an ipsilateral hemispheric stroke (3) or transient ischemic attack (4), two patients had a contralateral stroke, and one patient was asymptomatic. Nine procedures were done under local anesthesia. Cerebral protection was established through a cervical common carotid (CCA) cutdown to create an external fistula between the ICA and the internal jugular vein with temporally CCA occlusion. Venous oxygen saturation (SVO(2)) was continuously monitored through a catheter placed in the distal internal jugular vein. Mental status and motor-sensory changes were categorized and assessed throughout and after the procedure.

RESULTS

All procedures were technically successful without significant residual stenosis. Mean ICA flow reversal time was 22 minutes (range, 15 to 32). Common carotid artery (CCA) occlusion produced a slight (SVO(2) = 72.6%+/-9.4) but significant decrease (P =.012) in SVO(2), compared with baseline (SVO(2) = 77% +/-10.5). During ICA flow reversal (SVO(2) = 72.4% +/-10.1) cerebral oxygen saturation did not change compared with CCA occlusion alone (P =.85). Transient balloon occlusion during angioplasty of the ICA (SVO(2) = 64.6%+/-12.9) produced a significant decrease in cerebral SVO(2) compared with CCA occlusion (P =.015) and compared with CCA occlusion with ICA flow reversal (P =.018). No mental status changes or ipsilateral hemispheric focal symptoms occurred during CCA occlusion with ICA flow reversal. One patient with contralateral ICA occlusion sustained brief upper extremity weakness related to the contralateral hemisphere. Five patients sustained a vasovagal response during balloon dilatation, four did not require treatment, and one had asystole requiring atropine injection. Mean SVO(2) saturation was not different in these five patients compared with the five who did not sustain a vasovagal response. No deaths or neurologic deficits occurred within 30 days after the procedure.

CONCLUSIONS

Our data suggest that transcervical carotid angioplasty and stenting with ICA flow reversal is well tolerated in the awake patient, even in the presence of symptomatic carotid artery disease. Cerebral oxygenation during ICA flow reversal is comparable to that during CCA occlusion. ICA angioplasty balloon inflation produces a decrease in cerebral SVO(2) significantly greater than that occurring during ICA flow reversal.

Transluminal thrombin injection and exclusion of a paramesenteric abdominal aortic aneurysm

Surgical repair of aortic aneurysms involving the visceral arteries carries high morbidity and mortality in poor surgical candidates. With current technology, visceral artery involvement generally precludes endovascular repair of aortic aneurysms. We report on a patient with a large abdominal aortic pseudoaneurysm involving the origin of the superior mesenteric artery. This aneurysm was successfully repaired by transluminal thrombin injection of the sac and exclusion with balloon expandable covered stents placed in the aorta.

Impaired Hyperemic Response Is Predictive of Early Access Failure

The aim of this study was to demonstrate that hyperemic response is a predictor of access failure. We conducted a review of a prospective database of dialysis access patients with preoperative hyperemia studies from June 1998 to August 2002. These consisted of bilateral brachial artery pressures followed by flow velocity measurements of the brachial artery and radial artery at rest and after 3 min of arm ischemia. Measurements were taken by using a cuff placed above the antecubital fossa and inflated to 20 mmHg above systolic pressure. There were no differences recorded in brachial artery pressures for the bilateral studies. Hyperemic response was entered into a stepwise Cox regression to determine its effect on access failure. Access failure was defined as failure to mature or thrombosis. Accesses were placed according to Dialysis Outcome Quality Intiatives (DOQI) guidelines. Kaplan-Meier survival analysis was performed. Log-rank testing was used to compare patency results. Censored end points were death, renal transplant, and access survival to the end of the study period. Fistulas that failed to mature were considered failures at 3 months. Arteries with a <5 cm/sec increase in peak systolic velocity were defined as nonresponders. The 59 arteries used for dialysis access were divided into two groups on the basis of their hyperemic response in cm/sec. The nonresponders were compared with the remainder of accesses performed. Accesses based on arteries with absent or minimal hyperemic response had significantly lower (p < 0.0005) secondary patencies by Kaplan-Meier analysis. Upon further stratification into radial and brachial arteries, the significant difference in secondary patency remained for radial artery--based accesses (p = 0.024) and approached statistical significance for brachial artery--based accesses (p = 0.057). A significant difference was not seen in primary patencies, indicating that accesses based on arteries with an acceptable hyperemic response are more likely to be salvaged by revisions. A nonresponsive radial artery was not a significant predictor of a nonresponsive brachial artery in the same extremity by binary logistic regression (p = 0.111), and a nonresponsive artery was not a significant predictor of nonresponsiveness in the corresponding artery in the contralateral extremity (p = 0.137). Cox regression analysis revealed that the hyperemic response is a significant predictor of failure to mature or thrombosis. Hyperemic testing is a useful means of evaluating adequate arterial inflow for dialysis access. Reduced or absent hyperemic response is an independent predictor of access failure.

[Medullar carcinoma of the thyroid gland: surgical treatment of mediastinal metastases]

Metastatic medullary carcinoma is related to very bad prognosis. Surgery, associated or not to radiotherapy, may be effective in controlling metastasis due to local invasion, as in mediastinal extension. We present a case of medullary carcinoma with mediastinal disease that was treated through mediastinal dissection following by complimentary radiotherapy. After three years of follow-up, the patient remains free of recurrence, although calcitonin levels have not become normal yet.

Transesophageal echo-guided endovascular exclusion of thoracic aortic mobile thrombi

Mobile luminal thrombus of the descending thoracic aorta is an unusual finding in patients with peripheral embolization. The diagnosis is best made with transesophageal echography (TEE). Traditionally, systemic anticoagulation and selective surgical thrombectomy are standard treatment. We present a case report of recurrent mobile thrombus despite surgical thrombectomy and systemic anticoagulation. We treated it with endovascular exclusion of a descending thoracic aorta emboligenic lesion with an endoluminal stent graft, using simultaneous TEE and fluoroscopic intraoperative guidance. The patient remains symptom-free 9 months after stent-graft implantation. TEE-guided endoluminal exclusion should be considered in treatment of descending thoracic aorta emboligenic lesions.

Thoracodorsal sympathectomy for severe hyperhydrosis: posterior bilateral versus unilateral staged sympathectomy

The aim of this study was to compare the results of simultaneous bilateral thoracodorsal sympathectomy in the prone position with those of anterolateral sympathectomy performed in two staged, separate procedures for the treatment of bilateral excessive sweating of the hands and axillae, and to describe our technique for bilateral, simultaneous thoracodorsal sympathectomy. From July 1995 to March 2001, 202 thoracodorsal sympathectomies were done in 101 patients for severe hyperhydrosis. There were 79 females (age range 20-46) and 22 males (age range 19-65). In 52 patients, anterolateral sympathectomies were performed in the supine position, using unilateral lung collapse, with both sides operated on in two separate, staged procedures. In 49 patients, bilateral sympathectomy was conducted during a single procedure, in the prone position, without using unilateral lung collapse. In comparing the results from these two methods, we concluded that simultaneous bilateral thoracodorsal posterior sympathectomy, has comparable safety, may improve outcome, decreases in half the number of hospital admissions, and produces a significant overall reduction in cost when compared with staged anterolateral sympathectomy for the treatment of severe hyperhydrosis.

Duplex scanning or arteriography for preoperative planning of lower limb revascularisation

OBJECTIVE

to compare the accuracy of duplex and angiography for the planning of lower limb revascularisation.

PATIENTS AND METHODS

Sixty limbs (82% with critical limb ischaemia) were assessed by means of duplex by one surgeon and by angiography by another in terms of the optimum inflow and outflow sites for arterial bypass. These data were then compared with the final operation performed which was used as the gold standard. Surgeons were blinded to the determinations of the other.

RESULTS

surgical plans based on duplex scan and angiography were correct in 77% (40/52) and 79% (41/52), respectively and plans based on the one imaging modality was modified by the other in only 1 and 2 instances. The diagnostic agreement between duplex scanning and arteriography was excellent (Kappa value=0.94, 95% C.I. 0.89-0.98).

CONCLUSIONS

the reliability of duplex scanning is comparable to digital angiography in the preoperative planning of lower extremity arterial reconstruction. However neither exam can be considered as the gold standard because intraoperative arteriography needs to be available in a significant number of infrapopliteal procedures.

Abdominal aortic coarctation, renovascular, hypertension, and neurofibromatosis

Abdominal aortic coarctation and renal artery stenosis associated with neurofibromatosis is an unusual cause of renovascular hypertension in children and young adults. Sustained hypertension despite pharmacological treatment carries significant end-organ deterioration, failure to thrive, and potentially lethal complications. Timely arterial reconstruction can render these children normotensive, allowing normal development and reducing long-term morbidity. Progression of the arterial occlusive process, however, may occur after surgery. Therefore, careful follow-up is mandatory following aortorenal reconstruction in children with neurofibromatosis.

Conservative hemodynamic surgery for varicose veins

Conservative hemodynamic surgery for varicose veins is a minimally invasive, nonablative technique that preserves the saphenous vein and helps avoid excision of varicosities. It represents a physiologic approach to the surgical treatment of varicose veins based on knowledge of the underlying venous pathophysiology gained through detailed duplex scanning. A change in venous hemodynamics is attained through fragmentation of the blood column by interruption of the refluxing saphenous trunks, closure of the origin of the refluxing varicose branches, and preservation of the communicating veins that drain the incompetent varicose veins into the deep venous system. After surgery, varicose veins regress through a reduction in hydrostatic pressure and efficient emptying of the superficial system by the musculo-venous pump. Obvious advantages of this technique are that it is done in an ambulatory setting, minimizes the risk of surgical complications, and permits a rapid return to full activity. The long-term hemodynamic improvement and recurrence rate of this technique remain to be established.