Simultaneous aortic reconstruction and bilateral renalrevascularization

104

Journal of VASCULAR SURGERY

Letters to the Editors

artery (ICA), and calculating a ratio from these measurements, it is possible to compare angiograms of different patients irrespective of magnification or sex of the patient. A technique for predicting normal vessel diameters in stenosing lesions in the carotid arteries was recently described by Williams et al) They found the diameter of the widest part of the carotid bulb to be 1.19-+ 0.10 (mean -+ 1 SD) times the diameter of the proximal part o f the CCA. Because o f the wide variation in the normal diameter of the carotid bulb, it seems reasonable to include 3 SD above and below the mean to define the normal range. This gives an upper limit of the normal ratio o f 1.5 for the diameter of the carotid bulb in relation to the diameter of the CCA. In relating the dilatation to the diameter of the (normal) part of the distal ICA, we consider a ratio of 2.0 to be above the normal limit. We applied these measurements in five patients with diagnoses o f true aneurysms proved by histologic methods, and in retrospect, in all patients the diameter of the dilatation was above the normal upper limits just defined. Histologic findings in these patients revealed severe atherosclerosis with remnants o f the attenuated media and elastic lamellae that were largely interrupted and fragmented. An example of these measurements is given in Fig. 1. The diameter of dilatation is 15.5 ram, the diameter of the CCA is 9.5 nml, and the diameter of the ICA is 7.0 mm. Thus diameter of dilatation is 1.6 × CCA diameter and 2.2 x ICA diameter, which is above the upper limits of normal and thus should be considered an aneurysm. Further experience is necessary to determine the precise predictive value of this method of measurement, but in the meantime the calculations described above may be used as a preliminary standard in defining carotid aneurysms. Koert P. de Jong, MD Pieter E. Zondervan, MD Hero van Urk, A4D

Departments of Surgery and Pathology University Hospital Rotterdan>Dijkzigt Dr. Molewaterplein 40 3015 G D Rotterdam The Netherlands REFERENCE 1. Williams MA, Nicolaides AN. Predicting the normal dimensions of the irlternal and external carotid arteries from the diameter of the common carotid. Eur J Vase Surg 1987; 1:91-6.

Simultaneous aortic reconstruction and bilateral renal revascularization To the Editors:

We read with interest the article by O'Mara et al. (J VAsc SUWG 1988;8:357-66) and commend the authors on their impressive results in this very challenging area of vascular surgery. We found this type of procedure to be

beneficial to renal ftmction and the control of hypertension in our own series of nine patients. Eight of these patients had an infrarenal aortic aneurysm and one had symptomatic aortoiliac occlusive disease. Revascularization was performed by means of USCI Bionit (Bard Europe Ltd., England graft material; a composite graft appropriate to the patient's vascular anatomy was constructed on a bench immediately before insertion. Graft patency was subsequently confirmed by digital subtraction angiography. There was one postoperative death caused by infarction of the colon, one patient experienced transient respiratory failure, and two had transient deterioration o f renal function. Six of the eight patients who survived have had a good result in terms of control of hypertension and stabilization of deteriorating renal fimction. However, in the light of our own experience we were concerned by the authors' practice of aortic replacement in the absence o f aneurysmal or symptomatic occlusive disease and their reasons for justifying it. We are not aware of any evidence to support their contention that this will prolong aortorenal graft patency, and the authors admit that they have not confirmed graft patency by postreconstruction arteriograms in most of their own patients. Although there was only one postoperative death in their series, five patients had major nonrenal complications that aortic replacement might have contributed to. It is our opinion that the balance of evidence in the literature suggests that simultaneous aortic and renal reconstruction carries a greater risk to the patient than renal revascularization alone. We believe that a satisfactory aortorenal graft inflow can be constructed in the presence of aortic atheroma in most patients, provided careful attention is given to suturing the anastomosis. We accept that there might occasionally be a patient in whom this is not possible, but we do not accept the authors' policy of aortic replacement merely because of atheroma of the aortic wall. Graham G. Cooper,MD, FRCS Aires A.B. BarrosD'Sa, MD, FRCS, FRCS(Ed)

Vascular Surgery Unit Royal Victoria Hospital Belfast BT12 6BA Ireland

Reply To the Editors:

We appreciate the comment by Drs. Barros D'Sa and Cooper on our recent article. In our study o f patients undergoing combined aortic reconstruction and bilateral renal revascularization, two thirds of the patients required correction of either an aortic aneurysm or symptomatic aortoiliac occlusive disease. In the remaining 11 patients angiographic and operative findings invariably revealed severe calcific and degenerative atheromatous disease in the native aorta, which rendered it unsuitable as a reliable source o f inflow to a renal artery bypass graft. It has been our experience that even with careful attention, a techni-