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Background: Coagulation and fibrinolysis parameters were compared between two strategies of heparinization during cardiopulmonary bypass (CPB) in patients who underwent aortic surgery with deep hypothermic circulatory arrest (DHCA) and retrograde cerebral perfusion (RGCP) with aprotinin., Methods and Results: From January 1994 to January 1996, 94 patients underwent aortic surgery with DHCA with aprotinin; replacement of the ascending aorta took place in 14 patients, arch in 69, and descending aorta in 11. Two million units of aprotinin was administrated in the priming of CPB, and 3 mg/kg heparin was given before CPB. During CPB, 49 patients had an additional 1 mg/kg/h heparin regardless of activated clotting time (ACT) [group A], whereas 45 patients had an additional 1 mg/kg/h heparin when ACT was less than 500 seconds [group B]. ACT, PT, aPTT, fibrinogen, AT-3, plasminogen, alpha2-PI (plasmin inhibitor), fibrin/fibrinogen degradation products (FDP), DD (D dimer), TAT (thrombin-antithrombin complex), PIC (plasmin-plasmin inhibitor complex), beta-TG (thromboglobulin), and PF-4 (platelet factor-4) were assayed. No difference was detected between the two groups regarding the duration of operation, CPB, aortic cross-clamping, DHCA, RGCP, and time from the end of CPB to admission to ICU. The heparin dose was greater in group A, but the protamine dose was similar. There was no difference in bleeding after perfusion or in ICU. Levels of TAT, fibrinogen, and DD were lower in group A. PIC, alpha-PI, and FDP value showed no difference. PF-4 and beta-TG were lower in group A, and the platelet count at the end of operation and the day after the operation was higher in group A., Conclusions: Platelets were better preserved and activation of the coagulation system during CPB was less severe in patients who had a regular additional constant heparin regimen irrespective of ACT in surgery for the aortic aneurysm with DHCA and aprotinin usage. An accurate monitoring system for heparinization is necessary to maintain appropriate anticoagulation during CPB in patients who are undergoing aortic surgery with DHCA using aprotinin.

Background: The maze procedure failed to abolish atrial fibrillation (AF) in 14% of patients with underlying organic cardiac lesions. Identification of contributing risk factors will improve results either by treatment of such factors or by avoidance of high-risk patients., Methods and Results: We analyzed 192 consecutive patients with AF undergoing three variations of the maze procedure performed simultaneously with correction of valvular diseases (n = 165), congenital anomalies (n = 19), isolated AF (n = 7), and ischemic disease (n = 1). Twenty-six preoperative factors and two postoperative cardiac size parameters were analyzed by multivariate analyses between patients with successfully ablated AF (n = 165) and those who remained in AF (n = 27) after the maze procedure. Among all factors, postoperative left atrial dimension was the most potent in predisposing patients to persistent AF. Duration of AF left atrial dimension, and cardiothoracic ratio were identified as preoperative risk factors, whereas modifications of the maze procedure and pathogenesis and location of underlying disease failed to have a significant prognostic impact on rhythm after surgery. Individual risk analysis using the three preoperative variables revealed that left atrial size reduction to normalize its dimension played a pivotal role in determining rhythm after the maze procedure., Conclusions: Results favor earlier performance of the procedure before these risk factors develop, after which omission of the procedure or extensive left atrial plication may be appropriate. This requires further study.

Background: The perioperative blood coagulation and fibrinolysis system in patients who underwent aortic surgery under deep hypothermic circulatory arrest with or without aprotinin usage was investigated., Methods and Results: Of 112 patients who underwent aortic surgery between December 1993 and April 1995, 60 had repair under deep hypothermic circulatory arrest. Thirty-nine patients had 2 million U aprotinin in pump priming and had no additional aprotinin. There were 20 patients with aortic dissections and 17 with atherosclerotic aneurysms. Twenty-two patients had left thoracotomy, and 17 had midsternotomy. Surgery consisted of replacement of the ascending aorta in 9 patients, total arch replacement in 11, distal arch replacement in 11, replacement of the descending aorta in 3, and replacement of thoracoabdominal aorta in 5. The control group was 21 patients who underwent operation under deep hypothermic circulatory arrest and retrograde cerebral perfusion but without aprotinin. Blood coagulation and fibrinolysis tests, consisting of activated clotting time, prothrombin time, activated partial thromboplastin time, fibrinogen, antithrombin III, plasminogen, alpha 2-plasmin inhibitor, thrombin-antithrombin complex, plasmin inhibitor complex, fibrin degenerative products, and D-dimer complex, were performed at various stages of surgery, before heparin administration, after heparin, 60 minutes and 120 minutes after beginning of the extracorporeal circulation, 1 hour after protamine administration, and 6 hours after protamine. Statistical analysis was performed with Student's t test, chi 2 test, and ANOVA. The amount of bleeding after perfusion was less in the aprotinin group, and bleeding during first 24 hours in the intensive care unit was less. Blood examination revealed that prothrombin time was higher after cessation of cardiopulmonary bypass in the aprotinin group. Thrombin-antithrombin III complex and alpha 2-plasmin inhibitor were higher during and after bypass in the aprotinin group. There was no difference in activated clotting time, activated partial thromboplastin time, fibrinogen, antithrombin III, plasminogen, plasmin inhibitor complex, fibrin degenerative products, and D-dimer complex., Conclusions: Clinical advantages of hemostatic effects of low-dose aprotinin and no apparent deleterious effects were demonstrated in patients who underwent aortic surgery under deep hypothermic circulatory arrest with retrograde cerebral perfusion. However, blood coagulation and fibrinolytic studies revealed subclinical hypercoagulation. Therefore, and adequate dose of heparin is required during deep hypothermic circulatory arrest.

Background: Relative regression of the pulmonary arterial size has been reported after a conventional bidirectional Glenn procedure. Maintaining a supplemental pulmonary flow could be of surgical value unless the option also militates against the efficacy of the partial right heart bypass., Methods and Results: Twenty-seven patients considered unsuitable for a Fontan-type procedure underwent a bidirectional Glenn procedure in the presence of forward flow from the ventricles to the pulmonary arteries, the flow being maintained through the pulmonary trunk in 22 or a systemic-to-pulmonary shunt in 5. There was one surgical death due to atrioventricular valvular regurgitation. Subsequently, 9 patients have successfully undergone a total cavopulmonary connection 2.6 +/- 1.9 years after the initial procedure. Preoperative and postoperative catheterizations revealed changes in arterial oxygen saturation (75 +/- 11% compared with 83 +/- 7%, P < .001) and end-diastolic volumes of the systemic ventricles (from 238 +/- 92% to 188 +/- 97% of the expected normal volume, P < .01), whereas no difference was detected in the mean cross-sectional area of the right and left pulmonary arteries compared with the expected normal value for the right pulmonary artery (from 76 +/- 21% to 81 +/- 20%) or in the ventricular ejection fraction (from 53 +/- 8% to 50 +/- 14%). The relative regression or growth of the pulmonary arterial size was statistically related to the size of the channel for forward flow., Conclusions: Maintenance of forward flow from the ventricle provides a feasible means, when performing a bidirectional Glenn procedure, of protecting against regression of pulmonary arterial size as well as off-loading the ventricles and improving arterial oxygen saturation.

Background: Persistent atrial fibrillation (AF) leaves patients symptomatic and at increased risk of thromboembolism even after otherwise successful cardiac surgery., Methods and Results: To treat AF secondary to cardiac lesions requiring surgery, we combined a modified maze procedure in 101 patients simultaneously undergoing valvular procedures (87), repair of congenital anomalies (12), and other procedures (2), including 24 repeat operations. Duration of AF varied from 0.1 to 30 years (average +/- SD, 8.8 +/- 7.0 years); the f-wave voltage ranged from 0 to 0.45 mV (0.15 +/- 0.09 mV); and cardiothoracic ratio varied from 40% to 99% (63 +/- 9%). Aortic cross-clamp time varied from 75 to 229 minutes (138 +/- 31 minutes), with bypass time ranging from 119 to 326 minutes (217 +/- 42 minutes). There were two early deaths (2%), no late deaths, and one episode of transient neurological ischemic attack in follow-up ranging from 1.0 to 3.1 years, for a total of 190 patient-years. Postoperative rhythms were sinus in 83 patients (82%), junctional in 4 (4%), and persistent AF in 14 (14%), each of whom had mitral valve disease. Patients with other underlying pathology had complete recovery of atrial rhythm. A normal-sized A wave was detected in 88% for transtricuspid flow and in 73% for transmitral flow, suggesting concomitant recovery of atrial contraction. Among 36 patients without mechanical valves, 30 (83%) with atrial rhythm and contraction have been taken off anticoagulation therapy, including 10 who are free of all medication., Conclusions: The results suggest that the combined approach is safe, effective, and indicated in patients who are judged capable of tolerating the procedure and likely to regain atrial rhythm.

Background: Although the Maze procedure successfully restores sinus rhythm in patients with heart disease and atrial fibrillation, it is still uncertain whether an addition of the Maze procedure in cardiac surgery is beneficial for exercise performance of the patients after surgery., Methods and Results: The Maze procedure was performed in 25 patients (age, 37 to 70 years) during valve surgery (18 patients) or closure of atrial septal defect (7 patients). A cardiopulmonary exercise test using ramp incremental protocol (15 W/min) was performed before and 1 month, 6 months, and 1 year after surgery. Sinus conversion was obtained in 23 of 25 patients 1 month after surgery. However, sinoatrial (SA) node response to exercise was attenuated by surgery: Mean heart rate (HR) was 83 +/- 13/min at rest, 94 +/- 13/min at 60 W, and 107 +/- 17/min at peak exercise. Peak oxygen uptake (PVO2) was unchanged at this period (before, 17.6 +/- 4.5 mL.min-1.kg-1; 1 month after, 17.5 +/- 4.2 mL.min-1.kg-1). Thereafter, SA node response was restored 6 months after surgery: Mean HR was 84 +/- 13/min at rest, 104 +/- 16/min at 60 W, and 130 +/- 20/min at peak exercise (P < .01 versus 1 month). PVO2 was also improved at this period (20.7 +/- 4.0 mL.min-1.kg-1, P < .01). The increase in PVO2 from 1 month to 6 months after surgery was correlated with the increase in peak HR (y = 0.73x +/- 3.6, r = .79). There were no further changes in heart rate response or PVO2 from 6 months to 1 year after surgery., Conclusions: Atrial fibrillation was successfully treated by combined treatment with surgical repair for organic heart disease and the Maze procedure. However, SA node response to exercise was attenuated early after surgery. Thus, exercise capacity was improved at the late phase after surgery, which was related to the extent of restoration in SA node response.

Background: In surgery for chronic mitral regurgitation, the mitral subvalvular apparatus, including annulus, may play an important role in preserving left ventricular (LV) performance. The suture annuloplasty for mitral regurgitation allows annular contraction of the mitral valve. The potential effects of suture annuloplasty on the postoperative LV performance have not been fully defined., Methods and Results: Global and regional LV function in 12 patients with suture annuloplasty were compared with 12 patients with conventional mitral valve replacement (MVR). Cineangiography and echocardiography were obtained before and 10.8 months after surgery. End-diastolic volume index and end-systolic volume index decreased significantly in both groups after surgery (p < 0.01). Ejection fraction remained unchanged in the suture annuloplasty group, whereas it decreased significantly in the MVR group after surgery (p < 0.01). There was a significant inverse relation between ejection fraction and end-systolic wall stress in the two groups after surgery (suture annuloplasty group, r = -0.69, p = 0.01; MVR group, r = -0.60, p = 0.04). The intercept on the y axis was significantly (p < 0.005) higher in the suture annuloplasty group than in the MVR group. In the suture annuloplasty group, cross-sectional area ejection fraction at the mitral valve level and at the papillary muscle level by LV two-dimensional echocardiography remained unchanged after surgery. In the MVR group, they decreased significantly after surgery (p < 0.01). There was a significant correlation between the cross-sectional area ejection fraction and the global ejection fraction at both levels after surgery. Therefore, the improvement of the regional wall motion can be attributed to the improvement of the global LV performance after suture annuloplasty., Conclusions: These data suggest that suture annuloplasty can provide more desirable postoperative LV systolic performance than conventional MVR by preserving both the contraction of the mitral annulus and the mitral valvular-ventricular interaction.

The effects of "pulsatile" bidirectional cavopulmonary shunt (BCPS) produced by the flow from the ventricle or Blalock-Taussig (B-T) shunt on ventricular function and pulmonary circulation were evaluated in 10 patients with univentricular heart from 3 to 37 months (mean, 16.6 +/- 9.5 months) after surgery. Age at operation ranged from 7 months to 15 years (mean, 5.5 +/- 4.5 years). In addition to the BCPS, pulmonary flow was supplied from a B-T shunt on the contralateral side of the BCPS in five patients, from the ventricle through the stenotic pulmonary valve in four patients, and from both the ventricle and a B-T shunt in one patient. There were no operative deaths; however, there were two late deaths from acute respiratory infection 10 and 13 months after operation. Mean pulmonary arterial pressure measured the first day after operation ranged from 10 to 19 mm Hg (mean, 14 +/- 3 mm Hg). Mean pulmonary arterial pressure at postoperative cardiac catheterization was less than 15 mm Hg (mean, 12 +/- 4 mm Hg). Pulse pressure ranged from 3 to 12 mm Hg (mean, 7 +/- 4 mm Hg). Arterial oxygen saturation increased significantly from 77 +/- 5% before BCPS to 86 +/- 4% immediately after discharge from the intensive care unit (p less than 0.005) and 85 +/- 3% (p less than 0.025) at late cardiac catheterization. Pulmonary arteriovenous fistula was not detected in contrast echocardiography and pulmonary arteriography. Systemic ventricular end-diastolic volume index decreased significantly (p less than 0.01) from 141 +/- 54 ml/m2 before BCPS to 98 +/- 35 ml/m2 1 month after BCPS by echocardiography.(ABSTRACT TRUNCATED AT 250 WORDS)

Problems in myocardial revascularization for coronary impairment due to Kawasaki disease were assessed in five patients 1 to 4 years old. Each patient had significant stenosis or complete obstruction with aneurysm formation. There were no operative or late deaths in the follow-up period of 1 to 10 years after operation. The coronary arteries, including the first diagonal branch and obtuse marginal branch, were 1 to 1.5 mm in diameter. Eight saphenous vein grafts used were 2.5 to 3.5 mm in diameter and the internal mammary arteries used in two patients, ages 2 and 4 years, were 1 mm in diameter. All nine grafts examined in the early postoperative period were patent. However, only three of eight saphenous vein grafts were patent in the late postoperative studies. One saphenous vein graft to the right coronary artery was found patent 7 years after surgery in a patient who had been operated on at the age of 3 years. Internal mammary artery grafts used in the last two patients in the series were both patent throughout the late postoperative period. This experience suggests that myocardial revascularization is surgically feasible and beneficial even in young children and that further study is warranted.

Thirty-six of 42 consecutive patients who underwent corrective surgery for tetralogy of Fallot were operated upon without or with minimum right ventriculotomy and with repair of the pulmonary valve. The other six patients underwent conventional right ventriculotomy primarily because they required external valved conduits for repair. One of the 36 patients (2.8%) died 11 days postoperatively. Postoperative hemodynamic and angiocardiographic studies were performed randomly in eight patients. The results were compared with those obtained from 21 control patients who underwent conventional corrective surgery with right ventriculotomy and without repair of pulmonary valve. There were no differences in the degree of residual pulmonary stenosis. Moderate-to-severe pulmonary regurgitation occurred in none of the patients who underwent the new procedures and in 24% of the controls. Cardiac and stroke volume indexes at rest measured postoperatively did not differ significantly between the two series of patients. The cardiac index for both series of patients increased significantly during isoproterenol infusion, measuring 7.29 +/- 1.97 l/min/m2 for the present series of patients (p less than 0.005) and 5.76 +/- 1.64 l/min/m2 for the controls (p less than 0.001). These two values were significntly different (p less than 0.05). Stroke volume index in the present series of patients increased significantly during isoproterenol infusions., from 37 +/- 5 ml/m2 to 45 +/- 15 ml/m2 (p less than 0.05), whereas that for the controls decreased significantly, from 43 +/- 10 ml/m2 to 38 +/- 12 ml/m2 (p less than 0.01). These differences in the response to isoproterenol infusion in the two series of patients indicated that right ventricular function after corrective surgery for tetralogy of Fallot was well maintained in patients who underwent the new method of operation. The two series of patients did not differ with respect to the development of right bundle branch block.

The effectiveness of cold crystalloid potassium cardioplegia was evaluated in 26 infants (age 27 days to 17 months, 7.5 +/- 5.2 months, mean +/- SD) who underwent intracardiac repair for various cardiac lesions. A myocardial biopsy sample was obtained before aortic cross-clamping (AXC) and 20 min after release of AXC (AXC time 22 to 161 min, mean 68 +/- 37 min), and semiquantitative assessment of the mitochondrial structure was made by scoring. The post-AXC score was significantly higher than the pre-AXC score (1.1 +/- 0.6 vs 0.4 +/- 0.4, p less than .001) for the whole group. Patients receiving preoperative catecholamine support had higher pre- and post-AXC scores than those who did not (pre-AXC score 0.7 +/- 0.4 vs 0.2 +/- 0.3, p less than .01; post-AXC score 1.4 +/- 0.5 vs 1.0 +/- 0.5, p less than .05). Infants less than 3 months old (n = 7) and those 3 to 12 months old (n = 11) had higher pre AXC scores than infants over 12 months old (n = 8). With respect to post-AXC score, only those less than 3 months old had significantly higher values than the other infants. These results indicate that the myocardial injury was not fully prevented by crystalloid potassium cardioplegia in infants, and that infants with preoperative heart failure and less than 3 months old appear to have increased myocardial susceptibility to ischemic injury under cardioplegia.

The effects of calcium and a prostacyclin (PGI2) analogue in the glucose-insulin-potassium (GIK) cardioplegic solution for the neonatal period and early infancy were evaluated. The assessment was based mainly on semiquantitative scoring of mitochondrial damage and intracellular edema in postreperfusion biopsies. Experimentally, 45 isolated perfused newborn rabbit hearts (age, 0-2 days) underwent 2 hours of global ischemia at 15 degrees C with a single dose of GIK cardioplegic solution and were subsequently assigned to three groups: Group 1 hearts (n = 15) were infused with basic GIK cardioplegic solution alone (no added calcium, but measured at 0.1-0.2 mM/l); Group 2 hearts (n = 15) received GIK cardioplegic solution with calcium (1.2 mM); and Group 3 hearts (n = 15) received GIK cardioplegic solution with calcium and a PGI2 analogue (OP-41483, 300 micrograms/l). Group 3 hearts showed significantly lower mitochondrial damage and intracellular edema scores than did Group 1 and Group 2 hearts (p less than 0.05). Hemodynamic measurement (aortic flow and coronary flow) results after reperfusion were also better in Group 3 hearts than in the hearts of the other two groups (p less than 0.05). In the clinical study with 18 infants who were less than 3 months old, the same three cardioplegic solutions were used. Group 2 (n = 6) and Group 3 (n = 5) infants showed significantly lower mitochondrial damage scores than did Group 1 (n = 7) infants. Group 3 infants also showed significantly lower intracellular edema scores than did Group 1 and Group 2 infants.(ABSTRACT TRUNCATED AT 250 WORDS)

Twenty-four patients with single ventricle, six with single left (SLV) and 18 with single right (SRV) ventricle, who received a Blalock-Taussig (BT) shunt at an average age of 3.2 years were studied. Ventricular function was assessed angiographically by end-diastolic volume index (EDVI) and ejection fraction (EF), and attempts were made to measure ventricular mass index (VMI) and VM/EDV. In 14 patients, the preoperative and postoperative results (average 2.4 years after placement of BT shunt) were compared in SLV (n = 5) and SRV (n = 9) groups. The SLV group showed significant increases in EDVI, VMI, and VM/EDV without a significant change in EF. The SRV group showed significant increases in EDVI and VMI, while EF decreased and VM/EDV was unchanged. Late death from congestive heart failure occurred in five patients with SRV. Three patients with atrioventricular valve regurgitation suffered late death. Among the patients with SRV, the late death group had significantly lower preoperative EF and VM/EDV compared with the survivors (n = 13). All of those with a preoperative EF of less than 0.50 and a VM/EDV of less than 0.35 g/ml suffered late death. In summary, patients with SRV appear to fail to develop adaptational hypertrophy to volume loading after the BT shunt procedure, with concomitant depression in ventricular pump function. Also, late cardiac failure seems likely to develop when low EF and VM/EDV are present preoperatively.

In order to obtain better operative results with less postoperative atrioventricular valve regurgitation, we have developed a new method of repair for the complete atrioventricular canal with a composite prosthetic patch called an endocardial cushion prosthesis, in which horizontal wings are attached to a vertical patch on both sides to compensate for the defective atrioventricular valve tissue. Ten patients ranging in age from 8 months to 8 years (mean 28.9 months) have been operated on with this technique since 1975. All patients except one showed severe preoperative pulmonary hypertension (over 50 mm Hg) in mean pulmonary artery pressure. Six patients had trivial-to-moderate mitral regurgitation before surgery. Nine patients survived the operation (operative mortality 10%). Postoperative mitral regurgitation was found in three of seven patients who underwent cardiac catheterization and angiocardiographic examination at an average of 4.4 months after surgery. The grades of mitral regurgitation were trivial in all. Mild-to-moderate tricuspid regurgitation was observed in five patients and there was a correlation between the grades of tricuspid regurgitation and pulmonary/systemic peak pressure ratio (r = .757, p less than .05). This method appears to be advantageous in preventing postoperative mitral regurgitation with low operative mortality. However, tricuspid regurgitation was not well avoided among the patients with persisting pulmonary hypertension.

Deep-hypothermic cardiopulmonary bypass with selective cerebral perfusion (SCP) was used in 34 consecutive patients with aneurysms involving the aortic arch or the adjacent part of the aorta. The ages ranged from 25 to 79 years (mean, 56 years). Atherosclerotic aneurysms were present in 14 patients, dissecting aortic aneurysms in 16, and other lesion types in four. Replacement of the ascending aorta was performed in 10 patients, replacement of the ascending aorta and arch in 12, replacement of the distal arch in two, and other procedures in 10. Perfusion techniques consisted of femoral artery perfusion and SCP to the brachiocephalic trunk and the left common carotid artery. The blood temperature was maintained at 16 degrees-20 degrees C. SCP time ranged from 25 to 214 minutes (mean, 123 minutes). Operative death occurred in three (9%) patients. Neurological sequelae occurred in one patient (cerebral infarction), but significant respiratory and hemorrhagic problems were not encountered. For the SCP protocols, we advise that perfusion pressures at bilateral superficial temporal arteries be kept at approximately 50 mm Hg and that venous oxygen saturation of the superior vena caval line or internal jugular vein be kept at above 90%. With appropriate monitoring, this method can be performed in aortic arch or related surgeries with low morbidity results.

Thirteen patients (ages 4 to 16 years) with univentricular heart of right ventricular type, nine with double-inlet right ventricle (DIRV), and four with mitral atresia who underwent a modified Fontan operation were reviewed. Among those with DIRV, right isomerism with a common atrioventricular (AV) valve was found in eight and situs inversus in one; among those with mitral atresia, AV discordance was found in two and concordance in two. Intra-atrial routing using a baffle with atriopulmonary anastomosis was the main procedure (11 patients). There were two operative deaths (one DIRV, one mitral atresia) and three hospital deaths, with an early mortality of 38.5% overall (DIRV 44%, mitral atresia 25%). Low cardiac output was the main cause of death, with relatively high right atrial pressure and with tachyarrhythmias in most of the patients. Mortality was 75% for patients with DIRV who had total anomalous pulmonary venous drainage (n = 4) and 20% for those without (n = 5). Preoperative ventricular volume and ejection fraction were not different between those with severely low cardiac output (n = 4, three deaths) and the others, whereas ventricular mass/volume ratio was significantly lower in the former group. Two late deaths (one DIRV, one mitral atresia) related to the AV valve regurgitation. These results may indicate a relatively poor outcome after the modified Fontan operation for patients with univentricular heart of right ventricular type as a result of basic anatomic and hemodynamic problems.