Saphenous vein aortorenal bypass grafts: Serial arteriographic study

Short vein grafts for cerebral revascularization

Experience with the use of a short saphenous vein bypass graft for cerebral revascularization is reviewed. Twenty patients with symptomatic atherosclerotic occlusive disease underwent a total of 21 bypass procedures. Cerebral revascularization was performed using a short (5 to 10 cm) saphenous vein graft (SVG) extending from the superficial temporal artery (STA) trunk anterior to the ear in 19 bypasses, or from the occipital artery (OA) immediately behind the mastoid process to the posterior temporal or angular branch of the middle cerebral artery (MCA) in two bypasses. The early patency rate for the SVG bypasses was 90%. Two of the four patients with SVG occlusion were found to have substantial resolution of a severe inaccessible internal carotid artery stenosis that was present preoperatively. Filling of multiple major branches of the MCA through the SVG was seen in 90% of patients on late postoperative conventional angiography. The STA trunk or proximal OA was consistently found to be enlarged on the late studies. None of the patients had recurrence of cerebral transient ischemic attacks. The procedure may be useful as a primary means of cerebral revascularization or as an alternative approach when a scalp artery cannot be used because of its small size, severity of arteriosclerotic changes (a common occurrence), or damage during its dissection. Cerebral blood flow studies suggest that the use of a short SVG has a more favorable effect upon the cerebral circulation than the conventional bypass procedure.

The current status of surgical therapy for renal artery disease

The first reports of surgically curable hypertension in the late 1930s led to enthusiasm among clinicians for removing kidneys with arterial stenosis in hypertensive patients. The development of vascular surgical techniques in the 1950s made it possible to achieve successful renal revascularization in many of these cases. However, the cause and effect relationship between a stenotic renal artery lesion and hypertension was poorly understood and many patients treated surgically had no improvement of blood pressure postoperatively. Continued experience in this field during the past two decades has significantly improved our understanding of the natural history and functional significance of renovascular disorders. Patients with renovascular hypertension can now be identified with a high degree of accuracy and successful renal revascularization is possible in most cases. Nevertheless, multiple factors must be weighed in determining whether medical or surgical therapy is more appropriate for a given patient. These include the causal relationship of renovascular disease to hypertension, the adequacy of blood pressure control with medical therapy, the natural history of untreated renovascular disease with particular regard for the risk of sustaining impaired renal function, the medical condition of the patient, the morbidity and results of surgical therapy, and the availability of other therapeutic options such as percutaneous transluminal dilatation.

Renal artery stenosis in children

Because high blood pressure in children is rare and most of these patients are asymptomatic, many are overlooked until they present with a hypertensive crisis or irreparable damage. Most children with renal artery stenosis are asymptomatic and the hypertension is detected only by blood pressure recording during physical examination. Angiography is the most helpful diagnostic study. It is generally agreed that renal artery lesions in children should be considered for surgical correction. An illustrated case is described.

Surgical treatment of renovascular hypertension in children: the roile of renal autotransplantation

We describe 2 children with renovascular hypertension treated successfully by autotransplantation, as well as an additional child in whom ex vivo microsurgical repair was attempted. The literature is reviewed and all patients within the pediatric age group with renovascular hypertension who were treated surgically are reported. The different types of vascular reconstructive techniques and, particularly, the previous use of autotransplantation are discussed.

Surgical management of branch renal artery disease: in situ versus extracorporeal methods of repair

Herein are presented the techniques and their respective indications that have been found most effective in replacing the renal artery and its branches. Aortorenal bypass and, occasionally, splenorenal bypass can be tailored to achieve in situ repair of most branch renal artery lesions. Extracorporeal renal revascularization and autotransplantation have been done on onar disease. Revascularization with preservation of renal parenchyma can now be achieved in almost all patients with branch renal artery disease.

Atherosclerotic renal artery occlusion extending into branches: successful revascularization in situ with a branched saphenous vein graft

In some patients successful renal revascularization can be done after complete renal artery occlusion. We report on a patient with atherosclerotic occlusion of the renal artery and its branches in whom an aortorenal bypass with a branched saphenous vein graft was performed in situ, with cure of hypertension and reversal of azotemia. This is a useful and versatile technique for replacing the renal artery and its major branches.

Postoperative changes in autologous vein grafts

Images

Surgical treatment of renovascular hypertension in the pediatric patient

Of 27 children who underwent surgical treatment for renovascular hypertension 16 (59 per cent) were cured, 5 (19 per cent) were improved and 6 (22 per cent) were failures. Improved results were obtained in patients with unilateral renal artery stenosis. Several reconstructive vascular procedures were used, and their relative efficacy and indications are discussed. Renovascular hypertension in children is a curable disease and revascularization with preservation of renal parenchyma should be the aim of surgical therapy in most cases.

Renovascular hypertension: pathophysiology, diagnosis, and treatment

Renovascular hypertension can result from renal artery lesions involving the main renal artery, or its branches. It is generally felt that the elevation of blood pressure results from excessive systemic vasoconstriction secondary to enhanced renin secretion by one or part of one kidney. Renin secretion is enhanced because of constriction of the renal artery and resultant intrarenal ischemia. Clinically patients cannot be distinguished from those with essential hypertension and diagnosis must be made with arteriography although urography and isotope renography may suggest the diagnosis. Surgical cure can be predicted if differential renal vein renin ratios lateralize but a non-lateralizing study does not necessarily mean that surgery will fail. In properly selected patients, surgical results are excellent.

Autogenous arterial grafts in the treatment of renal artery stenosis

Twenty-three patients who underwent renal revascularization with autogenous arterial bypass grafts for renovascular hypertension are reviewed. The arterial autograft consisted of the hypogastric artery in 19 cases and a free splenic artery graft in 4. Eighteen patients were cured (78 per cent), 4 improved (18 per cent) and there was 1 failure (4 per cent). There were no cases of graft stenosis or occlusion. Postoperative morbidity was minimal and there was no operative mortality. When such grafts are available they provide an excellent means to achieve successful long-term renal revascularization.

RENAL AUTOTRANSPLANTATION FOR RENOVASCULAR HYPERTENSION: REPORT OF FOUR CASES(*)

Images

AUTOGENOUS INTERNAL ILIAC ARTERY IN THE TREATMENT OF RENOVASCULAR HYPERTENSION IN CHILDREN

Images

Intimal hyperplasia. A cause of radial artery aortocoronary bypass graft failure

Autogenous radial artery grafts have been advocated for those situations in which adequate saphenous vein is not available for aortocoronary bypass procedures. It was anticipated that autogenous artery would demonstrate less predilection to develop the intimal proliferative changes seen with vein grafts in the arterial system. Early clinical experience with 79 patients receiving one or more radial artery grafts has shown that the radial artery is not spared occlusive intimal proliferative changes. Although early restudy of 6 patients was encouraging, late restudy in 29 patients showed 22 of 34 radial artery grafts (64.7%) to be unsatisfactory. Recovered grafts from 3 patients who required a second operation revealed severe generalized intimal hyperplasia. On the basis of this experience we no longer consider the radial artery an alternative conduit for aortocoronary bypass.

Ex vivo renal artery reconstruction

Ex vivo renal artery reconstruction and autotransplantation is a relatively recent addition to the surgical armamentarium for renal vascular hypertension. Ten consecutive patients were considered for this surgical therapy and form the basis of this communication. The patients were treated by a combination of methods including bilateral ex vivo reconstruction, unilateral in situ and contralateral ex vivo reconstruction, and unilateral ex vivo reconstruction and contralateral nephrectomy. Replacement of the diseased segment of the renal artery in all ex vivo reconstruction consisted of arterial autografts including hypogastric artery, splenic artery, common iliac, and external iliac artery. In the ex vivo reconstruction, the ureter was either left intact or was transected and reconstructed by standard ureterovesicle implantation. After surgery all patients became normotensive without antihypertensive medication. Although this is a relatively small series, the uniform good results in these patients with extensive disease suggest that ex vivo renal artery reconstruction is a safe and effective method of treatment. Thus, it should be more widely applicable, expecially in those patients with renal vascular disease who were previously thought to be inoperable or eligible for nephrectomy only.