Asymptomatic carotid stenosis

LETTERS TO THE EDITOR

Minimally Invasive Nonendoscopic Thyroid Surgery

had colloid cysts or follicular adenomas. The patients ranged in age from 26 to 63, and 16 were women. Resected adenomatous masses measured up to 7 cm or larger. Seventeen of the 19 patients were discharged home 2 to 3 hours after surgery. One patient who had two procedures was admitted to the hospital because of anxiety, but was discharged the next morning. I believe it is more important to perform miniincision thyroidectomy rather than minithyroidectomy and would encourage the concept of same-day surgery using remote outpatient surgicenters and rapid discharge.

Raymond A Dieter, MD, FACS Naperville, IL I enjoyed the article titled “Minimally invasive, nonendoscopic thyroid surgery” by Ferzli and colleagues1 in the May 2001 issue of the Journal. They have brought up a number of interesting points and have demonstrated their enthusiasm for a minimally invasive as compared to an endoscopic approach for resection of the thyroid and its lesion. The study included 84 individuals ranging in age from 18 to 95 years. They have described their technique well and have demonstrated a minimal complication rate in these patients. The article illustrates the incidence of follicular adenomas, papillary carcinomas, and multinodular goiters in this group.1 Comments were made regarding the mean hospital stay of 1 day, and five of their procedures were done on an outpatient basis with patients being discharged a few hours later. Seventy-eight of their patients were discharged as observation bed or 23-hour admits. I would like to comment on the location of the surgical procedure. I have performed 19 consecutive open thyroid procedures without division of the strap muscles at the Center for Surgery in Naperville, IL, a remote outpatient nonhospital surgicenter. Six of the patients had a papillary carcinoma and an additional six patients

REFERENCES 1. Ferzli GS, Sayad P, Abdo Z, Cacchione RN, Minimally invasive nonendoscopic thyroid surgery. J Am Coll Surg 2001;192:665– 668.

Reply George S Ferzli, MD, FACS Staten Island, NY This letter is in response to Dr Dieter’s letter regarding the above article. We appreciate his comments and share his enthusiasm for miniincision thyroidectomy. We will caution against routine outpatient thyroid surgery and would prefer a selective approach.

Asymptomatic Carotid Stenosis

before additional and unrelated elective surgery” is not justified by the data presented in the article, or indeed by data from clinical trials. Further data are needed before such a course of action can be recommended. Currently, there is uncertainty regarding the benefit of CEA in unselected patients with asymptomatic carotid disease (ACD). Data from the Asymptomatic Carotid Artery Study (ACAS)2 and the North American Symptomatic Carotid Endarterectomy Trial (NASCET)3 reveal that the risk of first stroke in patients with ACD is less than 2% per year. The risk increases with higher degrees of narrowing (18.5% at 5 years in

Jose´ G Merino, MD, MPhil, Jacksonville, FL, Edward H Wong, MB, ChB, FRACP London, Ontario, Canada We read with interest the article by Hagino and colleagues1 in the May issue of the Journal. The risk of postoperative stroke in patients with asymptomatic carotid artery stenosis is real. But we believe that the concluding advice regarding “strong consideration of prophylactic carotid endarterectomy (CEA) in patients with asymptomatic, critical, and preocclusive carotid stenoses

© 2001 by the American College of Surgeons Published by Elsevier Science Inc.

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Letters to the Editor

the 75% to 94% stenosis group in NASCET) but decreases in the preocclusive group.3 ACAS showed that endarterectomy was marginally beneficial in patients with ACD (number needed to treat [NNT] ⫽ 67 at 2 years) as long as perioperative complication rates were less than 3%.2 Complication rates in trials of surgery for ACD,4 and in routine clinical practice,5 are higher than in ACAS, even greater than 10%.5 When the rate of complications approaches 5% the benefits of CEA are negated, and the surgery could even be harmful. Patients who are undergoing unrelated surgical procedures, such as those described by Hagino and coworkers1 may be at a higher risk of complications. Unselected CEA would be expected to be of marginal benefit in terms of prevention of subsequent strokes or death. The problem is compounded by the fact that up to 45% of strokes in the territory of an asymptomatic stenotic carotid are not from large-artery disease.3 CEA does not prevent these strokes. When only large-artery strokes are counted as the outcome of interest in ACAS, the absolute risk reduction of stroke is 3.5% at 2 years (NNT ⫽ 111).3 The case series reported by Hagino and associates does not give information regarding the stroke subtype of the patients, or the results of the stroke workup. Without this information it is impossible to determine whether endarterectomy would be useful in each particular patient. At a more fundamental level, there is a danger in deriving conclusions about clinical management from small case series, such as the one by Hagino and associates, where 11 cases were ascertained over 10 years. Because information about the number of interventions performed and the total number of patients with asymptomatic carotid artery disease who underwent a surgical procedure is not provided, incidence rates of stroke, or even proportions of patients with ACD who have strokes postooperatively, cannot be calculated. There may indeed be a subgroup of patients with ACD who benefit from prophylactic CEA before they undergo unrelated surgical procedures. Until further information is known, preferably from clinical trials where patients are stratified according to risk categories based on functional parameters such as plaque ultrasound6 or MR characteristics, or the presence or absence of emboli on transcranial Doppler, treatments must be made at an individualized level, taking into consideration the risks and possible benefits that accrue to each individual patient in the face of evidence known to date. This evi-

J Am Coll Surg

dence does not support prophylactic CEA in patients undergoing unrelated operations. REFERENCES 1. Hagino RT, Rossi PJ, Rossi MB, et al. Asymptomatic carotid stenoses and unrelated operations: Should we be more aggressive? J Am Coll Surg 2001;192:608–613. 2. Executive Committee for the Asymptomatic Carotid Atherosclerosis Study. Endarterectomy for asymptomatic carotid artery stenosis. JAMA 1995;273:1421–1428. 3. Inzitari D, Eliasziw M, Gates P, et al. The causes and risk of stroke in patients with asymptomatic internal-carotid-artery stenosis. N Engl J Med 2000;342:1693–1700. 4. Taylor DW, Barnett HJM, Haynes RB, et al. Low-dose and highdose acetylsalicylic acid for patients undergoing carotid endarterectomy: a randomized controlled trial. Lancet 1999;353:2179– 2184. 5. Chaturvedi S, Aggarwal R, Muragappan A. Results of carotid endarterectomy with prospective neurologist follow-up. Neurology 2000;55:769–772. 6. Kistler JP, Furie KL. Carotid endarterectomy revisited. N Engl J Med 2000;342:1743–1745.

Reply Ryan T Hagino, MD, FACS, San Antonio, TX, G Patrick Clagett, MD, FACS, Dallas, TX We appreciate the commentary provided by Drs Merino and Wong regarding our article entitled “Asymptomatic carotid stenosis and unrelated operations: Should we be more aggressive?”1 They have correctly noted the relative benignity of the asymptomatic carotid stenosis demonstrated in the medical arm of the Asymptomatic Carotid Atherosclerosis Study (ACAS) trial.2 But difficulty may arise in attempting to extrapolate the results of the ACAS or other trials to our patient cohort. As noted in our article, our patients suffered from a particularly severe form of anatomic carotid occlusive disease; the majority had critical, preocclusive lesions in excess of 90% diameter reduction. The ACAS trial noted modest, but significant benefit of endarterectomy in reducing the 5-year stroke risk for lesions in excess of 60% diameter reduction. But only 30% of enrolled patients had angiographically documented lesions exceeding 80% diameter reduction, and only 5% had stenoses greater than 90%. In addition, none were undergoing elective, unrelated operations.2 Subgroup analysis of these patients with advanced stenoses did not have significant statistical power for meaningful analysis. Our study represents