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Notes: Abstract Objectives: Nitric oxide (NO) gas infusion to the oxygenator, as well as heparin-coated bypass circuits, have been reported to attenuate blood activation induced by the interaction with the artificial surfaces of an extracorporeal bypass circuit. Using a mock circulation model, we compared the effect of each and also evaluated the effect of their combination on attenuating bypass-induced blood activation. Methods: A miniature closed bypass circuit was primed with diluted fresh human blood and perfused for 180 minutes using a centrifugal pump. NO gas (0, 50, or 100 ppm) was infused to the oxygenator sweep gas of either a non-heparin-coated or a heparin-coated circuit. Platelet counts, β-thromboglobulin, platelet factor 4, complement-3 activation products and granulocyte elastase were measured at 0, 30, 60, 120, and 180 minutes after starting the perfusion. Results: One hundred ppm of NO was statistically equivalent to the heparin-coated circuit for attenuating bypass-induced blood activation, and a combination of the two significantly surpassed the results of either modification alone. Fifty ppm of NO alone provided only a slight attenuation of blood activation as compared with the non-heparin-coated circuit, though the difference was not significant. A combination of 50 ppm NO and the heparin-coated circuit did not significantly enhance the effects of the heparin-coated circuit alone. Conclusions: The combination of NO gas infusion and heparin-coated circuits appears to be a useful and promising modification for enhancing the attenuation of bypass-induced blood activation, though the optimal dose of NO infusion in terms of effectiveness and adverse effects to the whole body remains to be established.(J Card Surg 2002;17:477-484)

Notes: Background: Operative survival after the Fontan procedure is good; however, there are some patients with disappointing results, especially those with atrial isomerism. Objectives: We tested whether the diameter of the pulmonary veins, which is reported as a useful indicator of pulmonary blood flow, predicts operative results after the Fontan operation. Patients and Methods: We evaluated 30 consecutive patients undergoing either the bidirectional Glenn anastomosis (BDG) or the Fontan operation. Age at operation ranged from 3 to 81 months (mean 30). Diagnosis was right or left isomeric heart in 15 patients, double-outlet right ventricle in 4 and various other malformations in 11. BDG was performed in 16 patients and the Fontan operation in 14 patients. The diameters of the pulmonary veins were measured proximal to the entrance into the atrium in the late phase of a pulmonary arteriogram. The pulmonary vein (PV) index (in mm2/m2) was calculated from the sum of the cross-sectional areas of these veins divided by the body surface area. Results: Of the patients undergoing BDG (± ancillary procedures), 12 had successful results and 4 had unsuccessful results. The PV index for hemodynamically successful patients was 361 ± 153 and 275 ± 60 mm2/m2 (mean 5 SD) for unsuccessful patients (p = 0.30). Of the patients who underwent the Fontan operation, 13 had successful and 1 had unsuccessful results. The PV index for successful patients was 〉285 mm2/m2 and 137 mm2/m2 for the nonsuccessful patients. The new pulmonary vascular resistance (PVR) calculated by using the PV index (mean pressure difference between the pulmonary artery and the atrium/PV index) for BDG patients with successful or unsuccessful results was 2.0 ± 0.5 or 3.5 ± 0.2 mmHg/mm2 per m2, respectively (p 〈0.01). The new PVR for Fontan patients with successful results was 〈.0 mmHg/mm2 per m2, while that for the patient with an unsuccessful result was 4.4. The new PVR completely separated patients into successful and unsuccessful groups, while conventionally calculated PVR did not (p = 0.63). Conclusions: PV index appears to be a useful morphological indicator of pulmonary blood flow and “new” PVR may improve the decision-making strategy for patients presenting with univentricular heart, especially those associated with isomeric heart.

Notes: Abstract Objectives: This study was done to clarify which diameter, that of the pulmonary arteries (PAs) or that of the pulmonary veins (PVs), more precisely reflects pulmonary blood flow (PBF) bilaterally and unilaterally. Methods: To evaluate bilateral PBF, we studied 15 consecutive patients with Kawasaki disease as normal patients and 30 patients with tetralogy of Fallot who received cardiac catheterization. To evaluate unilateral PBF, 20 patients with various congenital heart diseases undergoing cineangiography and lung perfusion scintigraphy were studied. The diameter of PA was measured immediately proximal to the origin of the first lobar branches bilaterally, and right PA area, left PA area, PA area (mm2), and PA index (mm2/m2) were calculated. The diameter of PV was also measured distal to the junction with the left atrium. Right PV area, left PV area, PV area (mm2), and PV index (mm2/m2) were calculated from these diameters. Pulmonary blood flow (PBF) was obtained by the Fick method during catheterization. To evaluate unilateral PBF, PBF was divided into right and left PBF according to the right/left perfusion ratio measured by lung perufusion scintigraphy. Results: Evaluation of bilateral PBF was as follows: in normal patients, PA and PV areas were correlated with body surface area (r = 0.88, p = 0.0001 and r = 0.93, p = 0.0001); PA index and PV index ranged from 248 to 436 (mean = 343) mm2/m2 and from 346 to 595 (mean = 466) mm2/m2, respectively, and were constant irrespective of body surface area; PA and PV areas were correlated with PBF in normal patients, as well as in patients with tetralogy of Fallot. There was a better correlation between PV area and PBF than between PA area and PBF in normal patients, as well as a significantly better correlation in patients with tetralogy of Fallot. Evaluation of unilateral PBF was as follows: right PV area was correlated with right PBF (p = 0.0002), while right PA area was not; left PV area and left PA area were correlated with left PBF; right/left PV area ratio was correlated with the right/left perfusion ratio with better agreement than right/left PA area ratio. Conclusion: Our data suggest that the size of PVs in patients with congenital heart disease may be more useful than the size of PAs to indicate bilateral and unilateral PBF than the size of PAs. Differences in PV area of each lung may be a suitable indicator of discrepancy in blood flow to each lung.

Notes: A patient who took 50–100 mg nitrazepam per day for 25 years is presented. 123I-IMP SPECT (autoradiography method) and EEG were performed sequentially on the subject during and after the withdrawal syndrome. Severe hypoperfusion of the whole brain on SPECT and diffuse slow activity on EEG were demonstrated during the withdrawal syndrome and subsequently remarkably improved. However, the hypofrontal pattern on both early and delayed images in SPECT was unchanged. The changes observed on SPECT and EEG reflect the pathophysiology of dependence and withdrawal. Additionally, the hypofrontal pattern remained unchanged suggesting that organic brain damage can develop as a result of chronic high-dose benzodiazepine abuse.