Interventional Therapy" An Alternative View John M. Porter, MD, Portland, Oregon

in his editorial (pp 99-100, this issue), Dr. Diethrich expresses the remarkable opinion that catheter-based interventional therapy is the future of vascular surgery and suggests that vascular surgeons had best "get on b o a r d " or risk abandonment of the entire field to interventionalists, including radiologists, cardiologists, and, presumably, unnamed other's. I strongly disagree with Dr. Diethrich's conclusions on many points. In the first place, the efficacy of interventional therapy has never been scientifically established, and all the claims of benefit to date are little more than anecdotes. It is the absolute responsibility of anyone proposing a new therapy to eventually prove its efficacy. It is not the responsibility of others to prove the new treatment is unsatisfactory. Having recently reviewed all the English language interventional literature, i take the clear position that interventional proponents have in no way proved the efficacy of their treatment. Mortality and acute complications of interventional therapy are comparable to that of good quality vascular surgery. Procedural cost averages about 40% of surgical costs, but a few repeat dilatations and the initial cost benefit is lost. The critical deficiency in the interventional literature is a remarkable dearth of objectively documented results and life-table presentation of procedural durability. The interventional literature continues to abound with such assessment terms as " p a t e n c y " (usually determined on the table at the conclusion of the procedure) and patients, self-assessment of "imp r o v e m e n t " . Even attempts to use an increased ankle/brachial index as an objective assessment are frequently tainted by the small print informing us that either an improvement in ABI or an improvement in pedal Doppler analogue arterial waveforms From the Division of Vascular Surgery, Oregon Health Sciences University, Portland, Oregon. Reprint requests: John M. Porter, MD, Oregon Health Sciences University, Department of Surgetw_, Division of Vascular Surgeo,, 3181 S.W. Sam Jackson Park Road, OPll, Portland, Oregon 97201-3098. 101

constitutes objective evidence of treatment efficacy. Interestingly, an overwhelming majority of interventional papers completely exclude from analysis all patients in whom treatment was attempted but was unsuccessful. This is clearly contrary to the universally accepted standard of analyzing outcome efficacy by the statistical convention of"intention to treat." Ignoring the initial failures makes as little sense as a vascular surgeon who, when faced with a thrombosed femoralpopliteal bypass several hours after surgery, simply excludes that patient from all future life-table analyses because the procedure was obviously initially unsuccessful. While there is precious little objective data concerning balloon dilatation (with or without laser), there is virtually none concerning stents and atherectomy. I have grown weary of the unending stream of anecdotal reports with neither objective documentation of outcome nor follow-up. Why are the interventionalists not held to the same reporting standards as the vascular surgeons? I retain great confidence in the ability of the American public to eventually sort out which procedures work and which do not. If interventional techniques eventually prove safer, cheaper, and as or more durable than vascular surgery, these techniques will appropriately prevail; if not, they will not. For the present, I wish advocates of interventional procedures would expend less effort verbally extolling the anecdotal procedural merits and a great deal more effort accumulating and publishing objective outcome data including long-term follow-up information. A major point raised by Dr. Diethrich is that vascular surgeons should be performing these procedures, and he descries our abandonment of arteriography. I well remember the " g o o d old d a y s " described by Dr. Diethrich when vascular surgeons routinely performed their own arteriography. Unfortunately, i also remember the attendant arterial complications, poor films, frequent contrast toxicity, and worse, i shed no nostalgic tears for the passing of this era. l regard my radiologic peers as

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well-trained and respected colleagues. I marvel at their arteriographic skills acquired through years of training and experience. Dr. Diethrich's suggestion that a three day hands-on training program will suffice for the acquisition of requisite skills is beyond absurd. What about a detailed knowledge of radiation physics and radiation safety required by all who use ionizing radiation? When will the threeday wonders acquire these skills? I find it curious that the same hospital medical staff credentialling organizations which grant vascular surgical privileges only after an approved vascular residency may grant full arteriographic privileges after only a rigorous three-day training period.

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ANNALS OF VASCULAR SURGERY

My summary position is that I regard all interventional therapy as experimental at present. No one really knows the objective early or late benefits of the procedures. The cost implications of extending these procedures to many patients currently insufficiently symptomatic to undergo vascular surgery have never been addressed. I strongly object to an economically driven nationwide program of interventional procedures in every community hospital and equally strongly object to three day courses purporting to make angiographers and interventionalists out of vascular surgeons. I am reminded of the apocryphal story, "Three days ago I couldn't even spell interventionalist. Now I are one."

Interventional therapy: an alternative view.

Interventional Therapy" An Alternative View John M. Porter, MD, Portland, Oregon in his editorial (pp 99-100, this issue), Dr. Diethrich expresses th...
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