Serial myocardial imaging with technetium-99m methoxyisobutyl isonitrile (9'Tc-MIBI) has been proposed for evaluating myocardial salvage after reperfusion. To define 'mTc-MIBI uptake before and after reperfusion, 17 open-chest dogs underwent 3 hours of left anterior descending artery occlusion and 3 hours of reperfusion. 9'Tc-MIBI was injected during occlusion (group 1) or after 90 minutes of reperfusion (group 2). Myocardial 99'Tc-MIBI activity was correlated with microsphere flow during occlusion and reperfusion. Anatomic risk area and infarct area were defined by postmortem vital staining and correlated with the perfusion defects defined by analysis of 99mTc-MIBI macroautoradiographs and gamma camera images of myocardial slices. The left ventricle was divided into 96 segments for gamma well counting. Flow and '9"Tc-MIBI activity were normalized to nonischemic values. Myocardial segments were grouped, based on occlusion flow, into zones: severely ischemic (<30% nonischemic), moderately ischemic (>30%o, .60%o nonischemic), mildly ischemic (>60%o, <90%1 nonischemic), and nonischemic (>90%o, < 120% nonischemic). Among dogs injected with "'Tc-MIBI during coronary occlusion (group 1), myocardial 99'Tc-MIBI activity correlated linearly with occlusion flow for both endocardial (r=0.91) and transmural (r=0.91) segments. The risk area defined by '9mTc-MIBI autoradiography (group 1) correlated with the postmortem risk area (p=0.94) but was 29O smaller than the anatomic risk area (p=0.03), reflecting the contribution of collateral flow. Among dogs injected with "'Tc-MIBI after reperfusion (group 2), myocardial 99"Tc-MIBI did not correlate with reperfusion flow in either endocardial or transmural segments. Among group 2 dogs, myocardial 9'Tc-MIBI activity was significantly less than reperfusion flow at the time of injection in the severely ischemic (25 ±5% versus 74±24% nonischemic,p=0.002), moderately ischemic (54±12% versus 96+15% nonischemic, p=0.001), and mildly ischemic (84±6% versus 93±3% nonischemic, p=0.002) zones. The defect area defined by 'mTc-MIBI autoradiography (group 2) correlated very closely with the postmortem infarct area (p=0.98). Thus, the myocardial uptake of 99mTc-MIBI during coronary occlusion correlates with occlusion flow and reflects the "area at risk." When 99mTc-MIBI was given after 90 minutes of reperfusion following 3 hours of coronary occlusion, the myocardial activity was significantly reduced compared with reperfusion flow in both necrotic and perinecrotic regions, reflecting myocardial viability more than the degree of reperfusion. (Circulation 1990;82:1424-1437 T X ahe current management of myocardial infarcinfarction, the extent of myocardial necrosis is detertion focuses on the application of acute mined by the "area at risk," collateral flow, and the interventional reperfusion techniques to duration of coronary occlusion.2 A noninvasive imagreduce myocardial necrosis.1 During myocardial ing technique that could 1) assess the area at risk, 2)

Background-Chronic allograft vasculopathy (CAV) is a major cause of long-term complications and mortality after heart transplantation. Although recipient factors have been implicated, little is known of the role of donor factors in CAV development. We sought to identify donor factors associated with development of CAV after heart transplantation.

Background Cardiac resynchronization therapy (CRT) using a left ventricular (LV) lead inserted via the coronary sinus (CS) improves symptoms of congestive heart failure (CHF), decreases hospitalizations, and improves survival. An epicardial LV lead is often placed surgically after failed percutaneous attempt, but it is unknown if they offer the same benefits. Objective To determine if patients who receive a surgical LV lead after failed CS lead placement for CRT derive the same benefit as patients with a successfully placed CS lead. Methods A total of 452 patients underwent attempted CS lead insertion. Forty-five patients who had failed CS lead placement and then had a surgical LV lead placed were matched with 135 patients who had successful CS lead placement. Results There were no major differences in preoperative variables between groups. Post-procedure complications of acute kidney injury (26.2% vs. 4.9%, P <0.001) and infection (11.9% vs. 2.4%, P=0.03) were more common in the surgical group. Mean long-term follow-up was 32.4 ± 17.5 months for surgical patients and 39.4 ± 14.8 months for percutaneous patients. At follow-up, all-cause mortality (30.6% vs. 23.8%, P=0.22) and readmission for CHF (26.2% vs. 31.5%, P=0.53) were similar between surgical and percutaneous groups. Improvement in NYHA class (60.1% vs. 49.6%, P=0.17) was similar between surgical and percutaneous groups. Conclusions Surgical LV lead placement offers functional benefits similar to percutaneous placement. This comes with the greater risk of perioperative complications including acute renal failure and infection.

The present donor criteria for heart and lung transplantation are too strict. Personal inspection of marginal thoracic donor organs will help to maximize donor utilization.

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ObjectiveThe authors review the general surgical complications of cardiopulmonary bypass, including newer procedures such as heart and lung transplantation, to identify patients at higher risk. Summary Background DataAlthough rare, the general surgical complications of cardiopulmonary bypass are associated with high mortality. The early identification of patients at increased risk for these complications may allow for earlier detection and treatment of these problems to reduce mortality. MethodsA retrospective review was performed of 1831 patients undergoing cardiopulmonary bypass from 1991 to 1993. This was done to identify factors that significantly contributed to an increased risk of general surgical complications. ResultsFactors associated with an increased risk of general surgical complications included prolonged cardiopulmonary bypass (p < 0.005) and intensive care unit stay (p < 0.002), occurrence of arrhythmias (p < 0.001), use of inotropic agents (preoperatively or postoperatively p < 0.001), insertion of the intra-aortic balloon pump (preoperatively p < 0.005, postoperatively p < 0.001), use of steroids (p < 0.001), and prolonged ventilator support (p < 0.001). Multivariate analysis identified use of the intra-aortic balloon pump (p < 0.001) as the strongest predictor of the general surgical complications of cardiopulmonary bypass. A variety of factors not contributing significantly to an increased risk also were identified. ConclusionsFactors indicative of or contributing to periods of decreased end-organ perfusion appear to be significantly related to general surgical complications after cardiopulmonary bypass.The general surgical complications of cardiopulmo-veals that patients undergoing transplantation using carnary bypass are reportedly rare (range 0.3-2.6%),1 2 but diopulmonary bypass have an even higher 30-day incifrequently lethal (range 15-63%).3-5 The literature re-dence of complications (7-20%),6-8 although relatively 489

Background Correct diagnosis of the causative organism is critical for the treatment of pacemaker and defibrillator pocket infections. No gold standard for this exists, although swab and tissue cultures are frequently used. The purpose of this study was to determine the value of ultrasonication of explanted generators in the diagnosis of pocket infections and asymptomatic bacterial colonization. Methods Samples were prospectively collected during pacemaker and defibrillator generator extractions for elective replacements, upgrades, or pocket infections. The devices were placed in an ultrasonicator for 5 minutes and the fluid sent for culture, along with swab and tissue cultures. Results Eighty-two patients with pacemakers (n = 46) or defibrillators (n = 36) underwent generator explantation, 66 of these for elective reasons and 16 for pocket infection. In patients with pocket infection, 15 (94%) received a definitive bacterial diagnosis using a combination of all three-culture modalities. Cultures were positive in 15 sonicated fluid, 13 tissue, and 11 swab samples, with Staphylococcus aureus and other skin flora commonly seen. In asymptomatic patients, 14 (21%) had positive cultures. Cultures were positive in 11 sonicated fluid, eight tissue, and two swab samples. Skin flora was commonly seen, but three of the sonicated fluid cultures grew gram-negative rods. No patients with asymptomatic colonization developed clinical infection during the follow-up period. Conclusions Ultrasonication is an inexpensive and simple technique that improves the bacteriologic diagnosis of device pocket infections. It also identifies a significant proportion of patients with asymptomatic colonization, although this is not a marker of future pocket infection.

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