Bilateral Upper Extremity Blood Pressure Measurements Should Be Routine prior to Coronary Artery Surgery

Abstract

To the Editor: Recently, we described a situation in which the diagnosis of left subclavian artery stenosis was made immediately prior to the induction of anesthesia in a patient scheduled for coronary artery bypass grafting with use of left internal mammary artery (IMA) and saphenous vein grafts.1Amar D Attai LA Gupta SK Jones AJ. Perioperative diagnosis of subclavian artery stenosis: a contraindication for internal mammary artery-coronary artery bypass graft.Anesthesiology. 1990; 73: 783-785Crossref PubMed Scopus (5) Google Scholar This diagnosis was suspected because a difference of 50 mm Hg between blood pressures in the upper extremities was found immediately prior to the induction of anesthesia. The diagnosis was confirmed with postoperative B-mode Doppler ultrasonography. The IMA was not used in this case because of the potentially lethal complication of coronary subclavian steal following bypass grafting using the IMA.2Brown AH Wellington MS. Coronary steal by internal mammary graft with subclavian stenosis.J Thorac Cardiovasc Surg. 1976; 73: 690-693Google Scholar On questioning the patient postoperatively, we discovered a 15-year history of being easily fatigued in his nondominant left upper extremity, which was associated with difficulty in obtaining blood pressure measurements in the same arm. This case illustrates the failure to note a physical sign that was present over the course of 15 years of medical and cardiologic consultations, including an evaluation before cardiac catheterization and preoperative surgical and anesthetic evaluations. Ideally, the rate-limiting step should be the evaluation done prior to cardiac catheterization. If a gradient greater than 20 mm Hg is present between arms, then subclavian artery stenosis is likely to exist in over 90 percent of these patients3Walker PM Paley D Harris KA Thompson A Johnston KW. What determines the symptoms associated with subclavian artery occlusive disease? J Vasc Surg. 1985; 2: 154-157Google Scholar; a study of the aortic arch can be done immediately without additional morbidity to the patient. The IMA graft has become the coronary bypass graft of choice,4Loop FD Lytle BW Cosgrove DM Stewart RW Goormastic M Williams GW et al.Influence of the internal-mammary-artery graft on ten-year survival and other cardiac events.N Engl J Med. 1986; 314: 1-6Crossref PubMed Scopus (2256) Google Scholar and its use is increasing. To date, coronary-subclavian steal following the use of the IMA has been reported in ten patients.5Olsen CO Dunton RF Maggs RP Lahey SJ. Review of coronary subclavian steal following internal mammary artery-coronary artery bypass surgery.Ann Thorac Surg. 1988; 46: 675-678Abstract Full Text PDF PubMed Scopus (104) Google Scholar Of concern, however, is the fact that other patients who suffered significant perioperative morbidity and mortality following coronary artery bypass grafting may have been casualties of undiagnosed subclavian artery stenosis. We, therefore, would like to emphasize the importance of bilateral blood pressure measurements in the prevention of this potentially lethal syndrome.