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In this paper we describe 1-year experience with a perspective operative protocol of emergency myocardial revascularization in extensive acute myocardial infarction (AMI). Entry criteria were: age75 years; anterior AMI with ST segment elevation4 leads, infero-postero-lateral or inferior and right ventricular AMI, within 6 hours from symptom onset. After coronary arteriography, an emergency staff, composed by cardiologists and cardiac surgeons, addresses the patients to coronary artery bypass grafting (CABG) or to percutaneous transluminal coronary angioplasty (PTCA). From November 1994 to November 1995, 35 patients were enrolled: 19 (mean age 54.3 +/- 9.7 years) underwent CABG and 16 were treated with PTCA. Myocardial protection was such as to restore energetic substrates and to prevent reperfusion injury: surgical technique consisted of antegrade-retrograde substrate-enriched blood cardioplegic solution delivery, early cardioplegic delivery on the infarcting area via a saphenous graft, retrograde controlled reperfusion before aortic unclamping and then prolonged reperfusion of the infarcted myocardium. In 8 patients (mean age 50.9 +/- 8.6 years), with anterior AMI and stable hemodynamics, a left internal thoracic artery graft was used, performing the prolonged controlled reperfusion retrogradely before aortic unclamping. In hospital death occurred in 1/19 (5.3%) patients because of cerebral hemorrhage. At a mean follow-up of 5.1 +/- 3.7 months 17 patients (94.4%) were in NYHA functional class I-II and 1 patient (5.6%) complained of effort angina, that was well controlled with medical therapy. Left ventricular ejection fraction calculated by echocardiography preoperatively, before discharge and at follow-up was respectively 39.3 +/- 12.7, 43.1 +/- 8.9 and 43.4 +/- 9.0%. In the last 8 consecutive patients thermodilution and transesophageal echocardiography monitoring were performed preoperatively and 12 hours after CABG: in all cases ejection fraction and cardiac index increased after CABG, from 42.2 +/- 13.5 to 48.6 +/- 14.3% (p = 0.01) and from 2.8 +/- 0.5 to 3.4 +/- 0.6 l/min/m2 (p = 0.005), respectively. The preliminary results show the effectiveness of this perspective protocol in the management of critically ill patients with extensive AMI.

The internal thoracic artery (ITA) flow steal syndrome after coronary bypass operations is rare. In the absence of subclavian artery stenosis, it has mainly been attributed to incomplete harvesting of the conduit along its proximal course. 1 Previous reports describe the recurrence of angina months or years after revascularization. The possibility of an ITA steal phenomenon associated with acute transmural myocardial ischemia occurring perioperatively is presented. Clinical Summary A 73-year-old, hypertensive, non‐insulin-dependent diabetic man with normal left ventricular function and no history of prior myocardial infarction or evidence of pulmonary disease underwent triple bypass grafting for worsening anginal symptoms caused by three-vessel coronary disease. The operation was performed with conventional cardioplegic arrest, and included left ITA grafting to the left anterior descending artery and saphenous vein bypass to the obtuse marginal and right posterior descending branches. The patient was weaned from cardiopulmonary bypass with no inotropic support or sign of myocardial ischemia. Extracorporeal circulation and aortic crossclamp times were 96 and 57 minutes, respectively. Three hours after arrival in the intensive care unit, the patient showed nonsustained ventricular tachycardia, immediately followed by signs of acute transmural anterolateral ischemia. The electrocardiogram gradually normalized with nitroglycerin infusion; intravenous amiodarone was also administered. No further instability occurred, and extubation was accomplished after control coronary angiography, which showed patent bypass grafts and an undivided collateral branch originating from the proximal ITA (Figure 1, A and B). Thereafter, however, blood gas exchanges remained borderline, and despite the application of continuous positive airway pressure, the patient subsequently experienced a low output state (oliguria, serum liver-specific enzyme increase, and paroxysmal supraventricular tachyarrhythmias) and eventually required reintubation for mechanical ventilatory support. The peak serum creatine kinase (myocardial band) level was 1139 (90) U/L. Catheterization was repeated on the basis of the previous angiograms to perform coil embolization of the ITA collateral branch (Figure 1, C). Cardiorespiratory function improved, and the patient was extubated the following day, showing no further complications. Echocardiography documented hypokinesia of the left ventricular apex with normal ejection fraction, and the patient was discharged on postoperative day 12. At 3 months’ follow-up, dobutamine stress echocardiography showed no inducible wall-motion abnormality and increased diastolic ITA flow, indicating a normal-functioning graft. 2

In an adult with severe dysphagia, diagnosis of aneurysmal aberrant subclavian artery was suspected on computed tomogram; no vascular ring was visible on arteriogram. A diverticulum of the aortic isthmus was surgically resected. Histologic analysis ruled out acquired disease. In conclusion, dysphagia related to esophageal compression may be caused by an isolated congenital aortic diverticulum. (J Vasc Surg 1997;26:142-3.)