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We describe a new method for aortic anastomosis in the repair of acute type A aortic dissection. The anastomosis site is prepared with the adventitial inversion technique, which converts a dissected aorta into a conduit lined with tough adventitia. The end is reinforced with felt strip outside and anastomosed with interrupted everting mattress and running sutures, resulting in complete hemostasis. This modified sandwich technique will likely be useful for the surgical treatment of acute aortic dissection.

Purpose: The present study evaluated whether the free radical scavenger edaravone (Radicut [Mitsubishi Pharma Co, Japan]) can suppress lower extremity postoperative reperfusion injury by evaluating muscle cell viability with immunohistological stain (cytochrome c oxidase stain)., Methods: Eight Lewis male rats (460 g to 510 g) were divided into two groups. In the control group, postoperative reperfusion injury models were created by clamping the bilateral common femoral arteries for 5 h and then releasing. In the other group, 9.0 mg/kg of edaravone was administered before clamping the bilateral common femoral arteries. After 5 h of reperfusion, the bilateral triceps muscles in both groups were stained with cytochrome c oxidase stain (each n=4 × 2). The positive areas of cytochrome c oxidase stain were measured and compared, using computerized densitometry (National Institutes of Health Image program, version 1.61)., Results: In the control group, the lower triceps muscles were not stained with cytochrome c oxidase. In the edaravone group, the lower triceps muscles were strongly stained with cytochrome c oxidase. The positive areas of cytochrome c oxidase stain were significantly greater in the edaravone group (133,000±12,000 μ(2)/mm(2), P<0.01) compared with the control group (8000±1300 μ(2)/mm(2))., Conclusion: The present study suggests that the preoperative administration of 9.0 mg/kg of edaravone may suppress postoperative reperfusion injury in a rat model.

We implanted a BVS-5000 biventricular assist system in a 29-year-old woman in cardiogenic shock due to fulminant myocarditis. Exchange of the left ventricular assist system (LVAS) from the BVS-5000 to a Toyobo LVAS and weaning from the right ventricular assist system were performed successfully without cardiopulmonary bypass. This simple, less invasive method may be useful for patients requiring LVAS exchange for long-term ventricular support.

The minimal cardiopulmonary bypass (mini-CPB) circuit, a closed system with neither cardiotomy suction nor an open venous reservoir and thus no air-blood interface, reportedly reduces blood loss and inflammatory reactions associated with coronary bypass surgery. We evaluated the inflammatory reactions in patients in whom coronary bypass operations were performed with conventional CPB or mini-CPB (n=15 each). Interleukin (IL)-6, IL-8, and neutrophil elastase levels; the neutrophil count; and the C-reactive protein value were measured before and immediately after surgery and on postoperative days 1 and 2. In addition, intraoperative blood loss and the transfusion volume were evaluated in these groups. Neutrophil elastase levels were lower in the mini-CPB group than in the conventional group on postoperative days 1 (127 +/- 52 vs. 240 +/- 100 microg/l, P=0.013) and 2 (107 +/- 17 vs. 170 +/- 45 micro/l, P=0.0001), as was the IL-8 level on postoperative day 1 (8.3 +/- 6.4 vs. 19 +/- 11 pg/ml, P=0.016). The intraoperative blood loss and transfusion volumes were significantly lower in the mini-CPB group than in the conventional group (510 +/- 244 vs. 1046 +/- 966 ml, P=0.012, and 691 +/- 427 vs. 1416 +/- 918 ml, P=0.0033). Thus, mini-CPB appears to attenuate neutrophil activation and cytokine release after coronary bypass surgery and, in addition, has some beneficial effects on blood conservation.

The hypoxic environment in tumor is reported to play an important role in pancreatic cancer progression. The interaction between stromal and cancer cells also contributes to the malignant behavior of pancreatic cancer. In the present study, we investigated whether hypoxic stimulation affects stromal as well as pancreatic cancer cells. Our findings demonstrated that hypoxia remarkably elevated the HIF-1alpha expression in both pancreatic cancer (PK8) and fibroblast cells (MRC5). Hypoxic stimulation accelerated the invasive activity of PK8 cells, and invasiveness was thus further accelerated when the hypoxic PK8 cells were cultured with conditioned medium prepared from hypoxic MRC5 cells (hypoxic conditioned medium). MMP-2, MMP-7, MT1-MMP and c-Met expressions were increased in PK8 cells under hypoxia. Hypoxic stimulation also increased the hepatocyte growth factor (HGF) secretion from MRC5 cells, which led to an elevation of c-Met phosphorylation in PK8 cells. Conversely, the elevated cancer invasion, MMP activity and c-Met phosphorylation of PK8 cells were reduced by the removal of HGF from hypoxic conditioned medium. In immunohistochemical study, the HIF-1alpha expression was observed in surrounding stromal as well as pancreatic cancer cells, thus indicating hypoxia exists in both of cancer and stromal cells. Moreover, the stromal HGF expression was found to significantly correlate with not only the stromal HIF-1alpha expression but also the c-Met expression in cancer cells. These results indicate that the hypoxic environment within stromal as well as cancer cells activates the HGF/c-Met system, thereby contributing to the aggressive invasive features of pancreatic cancer., (Copyright 2006 Wiley-Liss, Inc.)

A 57-year-old woman who complained of exertional dyspnea was diagnosed as having severe aortic valve stenosis and mitral valve regurgitation. The patient underwent double valve replacement with a mechanical prosthesis. Postoperative laboratory data showed unusually high serum lactate dehydrogenase (LDH) levels, even though no perivalvular leakage was detected by echocardiography. Tetany occurred suddenly owing to hypoparathyroidism, which seemed to be a late complication after thyroidectomy. After calcium administration, the symptoms dramatically diminished, as did the serum LDH levels. Hypoparathyroidism should be doubted if serum LDH levels increase higher than the normal range following valve replacement without obvious perivalvular leakage.

We successfully occluded an intractable digestive tract fistula by injecting it with absolute ethanol after all other treatments failed. A 48-year-old man suffered from a complex and relapsing digestive tract fistula after curative surgery for advanced colon cancer invading the pancreas and duodenum. After conservative management by fasting, drainage, and irrigation failed, fibrin glue infusion achieved only transient occlusion. We performed surgical repair and he was discharged from hospital, at which time fistulography showed no fistula. However, 1 month later fistulography showed that the fistula had recurred and involved the transverse colon, stomach, and intrahepatic bile duct via the jejunum. Finally, we gave five injections of absolute ethanol into the fistula, which resulted in complete occlusion within 6 months. Considering its clinical efficacy, safety, and cost efficiency, we think that ethanol sclerotherapy is a feasible treatment for intractable digestive tract fistula when conservative therapy fails.

Background: Deep hypothermic circulatory arrest (DHCA) without retrograde cerebral perfusion (RCP) has a strict time limit. We modified a surgical technique for anastomosis to shorten the period of DHCA and unilateral cerebral perfusion (UCP)., Methods: Between March 1993 and August 2001, retrospective analysis was done on 23 consecutive patients, who underwent aortic arch replacement with branches. The patients were divided into two groups: DHCA group and UCP group. The DHCA group, in which DHCA alone and without additional cerebral perfusion was performed, comprised of nine patients. Proximal aortic anastomosis was performed first during systemic cooling; then both the brachiocephalic artery and left carotid artery were reconstructed with the branches of the artificial graft during circulatory arrest; thereafter, cerebral and coronary perfusions were resumed. The UCP group, in which DHCA was not used but right hemisphere perfusion during deep hypothermia was performed when the origin of brachiocephalic artery was safely clamped, consisted of 14 patients., Results: Mean time of DHCA was 18.8+/-4.2 minutes and that of right hemisphere perfusion time was 11.0+/-3.8 minutes, respectively. Twenty-one patients survived the surgery (91.3%), and two (8.7%) died during hospitalization. Transient cerebral complication occurred in four patients in the DHCA group and all recovered. Logistic regression analysis revealed that DHCA was the only parameter to significantly influence temporary neurological dysfunction. There was no other significant difference between the two groups., Conclusion: With our modified and simple surgical technique for aortic arch repair, we were able to successfully shorten the DHCA time and right hemisphere perfusion time. However, because DHCA was the only parameter to significantly influence temporary neurological dysfunction, some form of continuous cerebral perfusion at deep hypothermia may be a safer method to preserve cerebral function.

Objective: We sought to investigate the changes of velocity profiles in the left anterior descending coronary artery after coronary artery bypass grafting using transthoracic Doppler echocardiography., Methods: Forty-five patients who received a bypass graft to the left anterior descending coronary artery were studied. Before coronary artery bypass grafting, Doppler velocity profiles of the distal left anterior descending coronary artery were recorded with transthoracic Doppler echocardiography. Peak systolic velocity, mean systolic velocity, peak diastolic velocity, mean diastolic velocity, total velocity time integral, systolic velocity time integral, and diastolic velocity time integral were measured. Three weeks after coronary artery bypass grafting, left anterior descending coronary artery antegrade flow in the distal portion of the anastomosis was obtained by using the same method. Coronary angiography was performed before and 3 weeks after coronary artery bypass grafting., Results: The overall success rate of measuring the left anterior descending coronary artery flow was 60.0% preoperatively and 80.0% postoperatively. In 25 patients, in whom all parameters were obtained both before and after coronary artery bypass grafting, the following increased significantly after coronary artery bypass grafting: peak systolic velocity (14.86 +/- 7.50 vs 25.07 +/- 17.02 cm/s, P =.0045), mean systolic velocity (9.86 +/- 5.42 vs 18.03 +/- 12.94 cm/s, P =.0026), peak diastolic velocity (24.26 +/- 12.54 vs 48.28 +/- 31.66 cm/s, P =.0021), mean diastolic velocity (14.94 +/- 6.65 vs 30.36 +/- 20.71 cm/s, P =.0022), diastolic velocity time integral (7.22 +/- 2.88 vs 15.55 +/- 10.39 cm, P =.0009), total velocity time integral (10.50 +/- 4.48 vs 19.27 +/- 12.63 cm, P =.0034), and diastolic-to-systolic velocity time integral ratio (3.09 +/- 1.53 vs 4.97 +/- 2.75, P =.0044). Angiography showed graft patency and no significant change in left anterior descending coronary artery stenosis in all patients., Conclusions: Transthoracic Doppler echocardiography showed a significant increase in some parameters in left anterior descending coronary artery flow after coronary artery bypass grafting. Measurement of left anterior descending coronary artery flow by means of transthoracic Doppler echocardiography might be a noninvasive method to evaluate the effect of bypass grafting on the left anterior descending coronary artery.

Background: Although the implantable cardioverter-defibrillator effectively prevents sudden cardiac death, patients are still prone to recurrence of ventricular tachyarrhythmias. Electrophysiologically guided surgery is the most effective modality in abolishing ventricular tachycardia, having a lower recurrence rate than pharmacologic therapy or catheter ablation. Return cycle mapping after entrainment has been shown to localize the central common pathway, which is the target region for ablation, without pacing at the pathway or recording the potentials from the pathway., Methods: To determine the accuracy and usefulness of return cycle mapping in surgery for ventricular tachycardia, we cryoablated 8 morphologies of ventricular tachycardia induced in postinfarction dogs with the guidance of return cycle mapping. The ventricular tachycardia was entrained from 3 to 5 different epicardial sites at a paced cycle length 10 to 20 ms shorter than the ventricular tachycardia cycle length and the epicardium was mapped with 61 unipolar electrodes during cessation of entrainment to construct return cycle maps. The return cycle was determined by subtracting the first activation time from the second activation time after the last stimulus in each electrode location, and the maps were then displayed on a computer., Results: The total analysis process was completed within 3 minutes by means of a computer with custom-made programs. The activation map during ventricular tachycardia did not localize the central common pathway in any morphology of ventricular tachycardia, because the pattern of activation was concentric and diastolic potentials were not recorded. Cryoablation of the region where the isotemporal lines of the return cycle equal to the ventricular tachycardia cycle length intersected resulted in termination of ventricular tachycardia in all morphologies. The intersection was 26 +/- 9 mm from the earliest activation site. Epicardial mapping with 253 electrodes during cryothermia showed that the region localized by return cycle mapping was the central common pathway sandwiched between the lines of conduction block and that the cryolesion connected the lines of block, blocked the rotating wave front, and resulted in termination of the ventricular tachycardia., Conclusion: Return cycle mapping provides an accurate and rapid means of localizing the central common pathway without the need for recording potentials from the pathway or pacing at the pathway in ablation for ventricular tachycardia.

Background: In chronic aortic regurgitation, eccentric hypertrophy, with combined concentric hypertrophy of the left ventricle, is an important adaptive response to volume overload, which in itself is a compensatory mechanism for permitting the ventricle to normalize its afterload and to maintain normal ejection performance (physiologic hypertrophy). However, progressive dilatation of the left ventricle leads to depressed left ventricular (LV) contractility and myocardial structural changes, including cellular hypertrophy and interstitial fibrosis (pathological hypertrophy)., Hypothesis: The study was undertaken to determine the relationship between left ventricular myocardial structure and contractile function in 14 patients with chronic aortic regurgitation by cardiac catheterization and endomyocardial biopsies., Methods: Myocardial cell diameter and percent interstitial fibrosis were obtained from biopsy samples. Contractile function was evaluated from the ratio of end-systolic wall stress to end-systolic volume index (ESS/ESVI) and the ejection fraction-end-systolic stress (EF-ESS) relationship, which was obtained from 30 normal control subjects., Results: Myocardial cell diameter correlated significantly with the ESVI (r = 0.72, p < 0.005), ejection fraction (r = -0.58, p < 0.05), and ESS/ESVI (r = -0.58, p < 0.05). The percent interstitial fibrosis also correlated inversely with ESS/ESVI (r = -0.71, p < 0.005). Compared with very few patients with an ESVI < 70 ml/m2, the majority of patients with ESVI > or = 70 ml/m2 had a cell diameter of > or = 30 microns and a percent interstitial fibrosis of > or = 10%. The nine patients who had depressed contractile function, as assessed from the EF-ESS relationship, had a higher percent interstitial fibrosis (p < 0.05) than five patients showing a normal EF-ESS relationship, despite the fact that there was no significant difference in myocardial cell diameter between them. Thus, advanced cellular hypertrophy and excessive interstitial fibrosis were significantly and independently associated with myocardial contractile dysfunction and appeared to be responsible for ventricular remodeling., Conclusion: Our findings suggest that in many patients with aortic regurgitation, eccentric hypertrophy changes its nature from physiologic to nonphysiologic during the earlier stages in the course of the disease rather than during the stage described previously.

To alleviate the invasiveness of surgical treatment for distal aortic aneurysm or dissection, we have been using a stented graft to replace the distal anastomotic suture of the descending aorta. We also developed a new stent graft implanting method for distal aortic aneurysm or dissection which uses cervical branch bypasses from the ascending aorta and requires no extracorporeal circulation. These new surgical treatments for distal arch aneurysm result in low surgical mortality (3.8%) and low surgical morbidity rates (stroke, 7.7%; respiratory complications, 7.7%; no renal complications). These results indicate that these new graft implanting methods using stent graft should be considered as a less-invasive surgical treatment for distal aortic aneurysm or dissection.

Background: Left-ventricular (LV) aneurysm formation after myocardial infarction (MI) leads to LV remodeling with global and regional cardiac dysfunction. LV aneurysmectomy (LVA) can often improve LV function, but changes of regional wall stress and systolic function in the noninfarcted segment before and after the operation remain poorly understood. The purpose of this study was to assess the effects of LVA on regional stress and systolic function in the noninfarcted region and to examine this procedure's impact on the LV remodeling in patients with LV aneurysm after myocardial infarction (MI)., Methods: Using quantitative left ventriculography and pressure measurements, 11 patients with an anterior LV aneurysm were studied before and 8 months after standard linear repair (LVA group), and 10 patients with an anterior transmural infarction who received coronary artery bypass grafting were also studied (CABG group) in an attempt to separate the effects of aneurysmectomy from the effects of bypass surgery. Regional end-systolic (ESS) and end-diastolic (EDS) stresses of the contractile segment (CS) were computed by Janz's method., Results: The total ejection fraction (EF) increased (p < 0.01) in the LVA group, whereas it did not change in the CABG group at 8 months after surgery. Both the end-diastolic and end-systolic volume indices of CS decreased (p < 0.01 and p < 0.01, respectively) in the LVA group, whereas both remained unchanged in the CABG group. The mean velocity of circumferential fiber shortening (mean Vcf) of CS increased substantially (p < 0.01) in the LVA group and, less significantly (p < 0.05), in the CABG group. Regional ESS and EDS decreased (p < 0.01 and p < 0.05, respectively) in the LVA group, whereas both remained unchanged in the CABG group. The increase in mean Vcf correlated strongly with the magnitude of decrease in ESS (r = -0.63, p < 0.01) in the LVA group but not in the CABG group., Conclusions: LVA can reduce regional afterload and improve ejection performance of the noninfarcted myocardium in many patients with a large anterior LV aneurysm and, moreover, may favorably affect the LV remodeling process after MI.

Background: The central common pathway, which is the target for ablation in reentrant ventricular tachycardia, can be localized by entrainment mapping techniques. However, localization of the pathway is not always possible because of the elevated pacing threshold and the low voltage and fractionated potentials at the pathway. We examined whether return cycle mapping after entrainment localizes the pathway without pacing at the pathway or recording the potentials from the pathway and determined the required electrode resolution to localize the pathway., Methods and Results: Epicardial mapping was performed with 253 unipolar electrodes during and after entrainment of 13 morphologies of ventricular tachycardia that were induced in dogs 4 days after infarction. The return cycle was calculated by subtracting the first activation time from the second activation time after the last stimulus and the return cycle distribution map was constructed for each stimulation site. The return cycle isochrones equal to the ventricular tachycardia cycle length converged on the lines of conduction block irrespective of the stimulation site, and the central common pathway was localized at the region between the intersections of the return cycle isochrones after entrainment from different stimulation sites. The potentials from the central common pathway were not required to localize the pathway, and the mapping accuracy did not change with or without analysis of the potentials from the pathway. According to the correlation between the electrode resolution and the mapping accuracy, an interelectrode distance of 8.5 mm was estimated as sufficient resolution for successful tachycardia termination during radiofrequency ablation guided by return cycle mapping., Conclusions: Return cycle mapping after entrainment localizes the central common pathway without pacing at the pathway or recording the potentials from the pathway. This new mapping technique could improve the success rate of the ablative procedures.

Background: Proto-oncogenes have been implicated in the pathogenesis of gene-mediated myocardial remodeling. In the human heart, however, it has not been clarified whether these proto-oncogenes are related to contractile impairment and structural alteration of the myocardium. The present study is designed to investigate the relationship between the c-Myc protein expression in the myocardium and the myocardial contractile dysfunction in patients with chronic aortic regurgitation who underwent indicated for aortic valve replacement., Methods and Results: Twelve patients (11 males and one female) with an average age of 55 years who underwent aortic valve replacement for isolated chronic aortic regurgitation were studied. The preoperative New York Heart Association class was II in four patients and III in eight. Ejection fraction, end-systolic volume index, end-systolic stress (Mirsky's form), and mass index of the left ventricle before surgery were 47+/-13%, 93+/-37 mL/m2, 223.2+/-44.4 Kdyn/cm2, and 210+/-38 g/m2, respectively. A left ventricular endomyocardial biopsy was performed to assess the myocardial cell diameter, fibrous content, and c-Myc protein expression in the myocardium. Cell diameter and fibrous content were significantly higher than those in five normal controls. C-Myc was detected in 9 of 12 present patients but in none of the normal controls. The degree of c-Myc expression had significant positive correlations with ejection fraction (r=0.93; P<.01) and end-systolic stress/end-systolic volume index (r=0.96; P<.01) and significant negative correlations with end-systolic volume index (r=-0.90; P<.01), cell diameter (r=-0.97; P<.01), and fibrous content (r=-0.92; P<.01), which suggested that the degree of c-Myc expression may have a significant negative correlation with myocardial contractility and myocardial hypertrophy., Conclusions: C-Myc expression may be related to the pathogenesis of myocardial remodeling in patients with chronic aortic regurgitation.

Background and Aims of the Study: Mitral annuloplasty has long been considered as the basic procedure for mitral regurgitation (MR). However, it is increasingly advisable to avoid foreign material and to use a method that provides greater adjustment for control of annular size. In this study, the semicircular suture annuloplasty (Paneth-Burr method) was evaluated for its efficacy and durability; the optimum size of the mitral annulus was also assessed., Methods: The Paneth-Burr method was modified using Gore-Tex suture, a crossing suture technique, and obturator for temporary annulus size adjustment. Between 1992 and 1994, 21 patients with an average age of 45 years (range: 8 months to 67 years) underwent such annuloplasty combined with various valvuloplasties and chordal reconstruction. The etiologies were degenerative in 11 patients, congenital in five, ischemic in three and endocarditis in two., Results: Mean MR grades (0-4) decreased from 3.3 +/- 0.6 to 0.2 +/- 0.4 after surgery. At an average 24 months follow up (range: 12 to 41 months), 16 patients showed no increase in MR, but five showed increased MR grades (all grade 3 or less: three grade 3 and two grade 2). Only one patient with ischemic MR required reoperation. Patients with increased MR grade during follow up had a larger intraoperative annular size (> 90% of normal), while those with < 90% of normal mitral annular size showed no increase in MR beyond grade 2, except one with ischemic etiology., Conclusions: A measured semicircular suture annuloplasty appears to be useful for MR, with acceptable efficacy and durability. In addition, the annular size to be adjusted at surgery is proposed to be < or = 90% of normal mitral annular diameter.

To establish a safe and reliable method for cerebral protection in aortic arch surgery, the authors attempted antegrade selective cerebral perfusion (SCP) based on the characteristics of jugular venous oxygen saturation (SjO2). Twenty patients were divided into two groups: a control group and SCP group. In the control group, in 13 adult patients undergoing cardiac surgery using standard hypothermic cardiopulmonary bypass, the relationship between SjO2 and nasopharyngeal temperature (NPT) during rewarming showed an inverse linear correlation:SjO2 = -2.3 NPT + 133 (r = 0.616). In the SCP group, seven patients with aortic arch aneurysm underwent surgery using SCP performed through direct cannulation of the innominate and left carotid arteries. While on SCP (83 +/- 24 min), the blood was warmed from 28 to 36 degrees C. Cerebral perfusion pressure of 40-60 mm Hg was necessary to maintain the SjO2 equal to the value in the control group at each NPT during SCP in all seven patients. None of the patients had any post operative complications. Our experience suggests that SCP can be safely performed at both mild hypothermia and normothermia under monitoring of perfusion pressure and SjO2 in aortic arch surgery.

Follow-up has been achieved in 41 hospital survivals who received xenograft valved conduits in the pulmonary position. The interval after operation ranged 6 months to 13 years (average 5.2 +/- 3.7 years) (+/- standard deviation). There has been 8 late deaths, 3 of which were sudden. Of the 11 reoperations, 7 underwent graft replacement with no operative death. The actuarial reoperation free survival rate was 73% at 5 years, and 54% at 10 years. There was a significant correlation between the interval after operation (x years) and the pressure gradient across the conduits (y mmHg). (y = 20.7 + 9.7x, r = 0.74, p < 0.001). Balloon dilatation of the conduits was performed in 15 patients. The mean conduit gradient was significantly (p < 0.001) reduced from 85 +/- 29 to 54 +/- 22 mmHg. However, the effect was not satisfactory enough and 4 patients received graft replacement after the balloon dilatation. These results warrant the avoidance of xenograft valved conduits in the pulmonary position, the safety of the graft replacement, and the limitation of the balloon dilatation for the stenosed conduits.

Cardiac catheterization and submaximal exercise testing was performed in 38 patients after repair of tetralogy of Fallot (TF), and compared to 6 control patients who had functional murmurs. Cardiac index, heart rate, and stroke volume index were significantly lower in the TF group than in the control group. Right and left ventricular end-diastolic pressure increased significantly during exercise, which was not found in the control group. Total pulmonary vascular resistance (TPVR), which decreased significantly with exercise in the control group, did not change remarkably during exercise. TPVR was significantly higher in the TF group than in the control group both at rest and during exercise. Several factors were compared between patients with good cardiac index (> 5.0 l/min/m2; Group 1) and poor cardiac index (< 5.0 l/min/m2; Group 2) during exercise. Stroke volume index, right ventricular ejection fraction at rest were significantly higher in Group 1 than Group 2. TPVR, right and left ventricular end-diastolic and end-systolic volume index were significantly lower in Group 1 than in Group 2. There was no significant difference in heart rate, left ventricular ejection fraction, residual pulmonary stenosis, right to left ventricular systolic pressure ratio, and severity of pulmonary regurgitation between two groups. These findings indicate that abnormalities of exercise tolerance in patients after repair of TF were related to poor response of heart rate, pulmonary vascular resistance, and systolic and diastolic ventricular function.

Background: A high incidence of refractory atrial flutter has been reported as a late postoperative complication of the Mustard procedure. The objective of this study was to reproduce experimentally the long-cycle-length atrial flutter that occurs in these patients and attempt to ablate the arrhythmia surgically., Methods and Results: Nine dogs underwent a simulated Mustard procedure, which included a longitudinal right atriotomy, a septectomy, and a continuous suture line placed in the usual baffle location. All animals were subsequently inducible into sustained atrial flutter after surgery. Activation-time electrophysiological maps of the various pathways of atrial reentry were determined using atrial endocardial molds containing 252 bipolar electrodes. Four distinct reentrant circuits were observed in the following locations: (1) around the tricuspid value annulus (n = 5; cycle length, 175 +/- 5 milliseconds), (2) around the atriotomy incision (n = 2; cycle length, 208 +/- 3 milliseconds), (3) in a pathway involving both atria (n = 1; cycle length, 180 milliseconds), and (4) around the mitral valve (n = 1; cycle length, 135 milliseconds). A common pathway for eight of the nine reentrant circuits included the free-wall segment of the right atrium (excluding the mitral valve circuit). In the first three animals, surgical ablation of the atrial flutter was not attempted, but an incision made perpendicular to the atriotomy down to the tricuspid valve annulus resulted in termination of the atrial flutter in the other six animals. One of these animals was subsequently inducible into an atrial flutter of different morphology (cycle length, 125 milliseconds) that involved an isolated left atrial reentrant circuit., Conclusions: The Mustard procedure creates several anatomic substrates that increase the probability of the heart to develop atrial flutter, and these may be amenable to subsequent surgical correction.

To elucidate the reversibility of right ventricular (RV) myocardial hypertrophy in tetralogy of Fallot (TF), 30 patients underwent RV endomyocardial biopsies 1 to 25 years (mean 9.7 +/- 6.6) after corrective surgery. Myocardial cell diameter was evaluated by comparing histopathologic data with preoperative patients with TF and normal subjects. As a whole, postoperative cell diameter was smaller than that of age-matched preoperative patients with TF, and larger than that of age-matched normal subjects. In 7 patients without significant residual pulmonary stenosis whose preoperative data were also available, cell diameter significantly decreased after surgery (17.1 +/- 2.1 to 14.0 +/- 2.1 microns, p < 0.01). There was a positive correlation between postoperative cell diameter and age at study (p < 0.01). To negate the influence of age, cell diameter was expressed in terms of a percentage of age-matched normal values (percent cell diameter). There was no significant correlation between percent cell diameter and age at surgery, age at study or the follow-up periods. There were positive correlations between percent cell diameter and the following parameters: RV systolic pressure (p < 0.05), percent normal RV end-diastolic (p < 0.05) and end-systolic (p < 0.01) volumes. These results demonstrate that RV myocardial hypertrophy in TF can regress to some extent after corrective surgery if significant residual pulmonary stenosis is avoided.

Background: Since the atria are thin-walled structures, most studies that have examined the spread of activation in the atria have assumed that they behave electrophysiologically as a two-dimensional surface. It was the objective of this study to determine whether or not this assumption is true by simultaneously mapping the epicardial and endocardial activation sequences in the right atrium., Methods and Results: Identical precisely superpositioned epicardial and endocardial electrode templates with 250 unipolar electrodes each were used to map the isolated canine right atrium (n = 8) during continuous perfusion and superfusion with Krebs-Henseleit buffer. Data were recorded during control conditions (normal sinus rhythm), continuous pacing (S1S1 = 300 msec), and premature stimulation (S1S2 = effective refractory period + 5 msec). Pacing was performed at two sites, one located on the inferior crista terminalis and one lateral to the crista terminalis on a pectinate muscle. Tachyarrhythmias were induced by a single extrastimulus during the continuous perfusion of acetylcholine (10(-3.5) mol/L). Individual electrode sites were correlated with the gross anatomy and histology. Activation time differences were calculated between each two corresponding epicardial and endocardial sites. There were differences in the activation times between the epicardium and endocardium during all experimental conditions. However, the average difference for each condition was < 1 msec, suggesting that overall activation did not spread faster on either the epicardium or the endocardium, even though in certain regions one surface could lead the other. The dispersion of time differences was smallest during normal sinus rhythm and continuous pacing (SD = 5.6-5.8 msec) and largest after premature stimulation (SD = 6.3 msec for crista pacing, p < 0.05; SD = 8.1 msec for pacing lateral to the crista, p < 0.001). Differences in the activation sequence correlated with the underlying anatomic architecture. The largest differences in activation times between the epicardium and endocardium were associated with those regions of the atrium where pectinate muscles ran below the epicardial surface. The pectinate muscles in those areas were often discontinuous with the epicardial surface and facilitated the discordant epicardial-endocardial activation. The discordant activation was also found in regions where the atrial wall thickness was < 0.5 mm and correlated with transmural differences in fiber orientation. A tachyarrhythmia induced in the presence of acetylcholine, which demonstrated a focal activation pattern, was shown to have a reentrant loop that used free-running muscle bundles connecting the epicardial and endocardial surfaces, resulting in a three-dimensional pathway., Conclusions: The findings of this study demonstrate that epicardial and endocardial activation can be discordant in specific regions and that discordance increases with abnormal activation sequences. Many of the differences in the epicardial and endocardial activation can be correlated with the heterogeneity of the anatomic architecture of the right atrium. The study also demonstrates that reentry can occur in a three-dimensional plane using the epicardial and endocardial surfaces connected by transmural muscle fibers.

We presented a 62-year-old female with constrictive pericarditis of an unusual anatomy. A calcified constrictive band, 2-3 cm wide, ran parallel to the frontal plane, coursing circularly along the anterior aspect of the great arteries, right atrium, diaphragmatic surface of the right ventricle, posterolateral aspect of the left ventricle and back to the great arteries. The course of the constrictive band was circular but completely different from that of typical annular constrictive pericarditis in which a constrictive band runs along the atrioventricular groove. Hemodynamic consequences of our patient was rather non-specific impairment of ventricular filling than functional valvular stenoses due to external compression characteristic for the typical annular constrictive pericarditis. Effective surgical relief of the constriction was accomplished under cardiopulmonary bypass and cardioplegic cardiac arrest.

We have assessed the long-term prognosis about cardiac death of isolated coronary artery bypass surgery from 1972 to 1988 in 361 consecutive patients. The duration of follow-up were from 0.4 years to 14.6 (mean 5.7) years. Of the 361 study patients, the operative morality was 4.7% (17 patients) and 29 patients (8.0%) died during follow-up, 11 (3.0%) of which were from cardiac causes. Actuarial survival rate was 85.2% at 10 years after surgery. The 10 year-survival rate was similar for patients with single, double, triple vessel disease, and left main trunk disease (94.5%, 83.7%, 75.1% and 89.1%, respectively). For patients with and without old myocardial infarction, the 10 year-survival rate was significantly different (75.4% and 93.3%, respectively) (p less than 0.005). In order to detect which factors of preoperative cardiac function among cardiac index, LV end-diastolic pressure, LV end-diastolic volume index, LV end-systolic volume index, and LV ejection fraction influenced the long-term prognosis, multivariant regression analysis was performed. Only LV end-systolic volume index was a significant factor, and the discriminative point was 50 ml/m2. For patients with LV end-systolic volume index less than 50 ml/m2 and greater than or equal to 50 ml/m2, the 10 year-survival rate was significantly different (88.3% and 32.9%, respectively) (p less than 0.005). In conclusion, the most significant factor influencing longterm prognosis after coronary artery bypass surgery was left ventricular end-systolic volume, indicating the importance of preventing preoperative dilatation of left ventricle.

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)

The Bentall operation was performed in 44 patients between March 1972 and December 1988. Twenty patients had stigmata of Marfan's syndrome, and 15 had aortic dissection. All showed annuloaortic ectasia. Follow-up ranged from 1 to 16 years (mean, 5.8 years). There were six early deaths (14%) and seven late deaths (16%), with actuarial survival at 10 years of 65 +/- 8%. The late deaths were mostly related to aneurysms occurring in the remainder of the aorta. No patient has undergone reoperation related to the composite graft, but six patients required seven subsequent operations on the remaining aorta. The actuarial probability of freedom from late death and subsequent operation at 8 years was 64 +/- 9% for the operative survivors, but it was 44 +/- 17% for the patients with aortic dissection and 37 +/- 19% for those with Marfan's syndrome. Postoperative angiography performed 3-168 months (mean, 42 months) postoperatively in 23 nonselective patients demonstrated recurrent true aneurysms at both or one of the coronary ostia (seven), persistent dissection distal to the distal aortic anastomosis (five), pseudoaneurysm at the left coronary ostium (one), pseudoaneurysm due to a small leak at the proximal aortic anastomosis (one), and partial dehiscence of the distal aortic suture line (one). Composite graft replacement carries a potential risk of various late complications. Our data support the concept that earlier detection and aggressive treatment of the late complications occurring in the remainder of the diseased aorta is necessary to improve long-term survival after the Bentall operation.

We have assessed the long-term results of heptagenerians after isolated coronary artery bypass surgery from 1979 to 1989 in 32 patients over 70 (mean 72) years old using actuarial techniques. In these patients, the long-term results could not be properly assessed because many other factors other than cardiac events influenced their survival. Accordingly, we compared our subjects with the general population matching the operative age and sex characteristics from life tables (= matched population). There was no operative mortality. The 5 year and 9 year survival rates were 93% and 31%. In the matched population, the 5 year and 9 year survival rates were 81% and 59%. The survival rate between the two groups was not significantly different. We concluded that the long-term results of coronary artery bypass surgery in patients over 70 years were similar to those of the matched population. Therefore, coronary artery bypass surgery should be offered to older patients for usual indications.

A 53-year-old woman who had severe mitral regurgitation associated with moderate tricuspid regurgitation and mild aortic regurgitation underwent mitral valve replacement with a 27 mm Björk-Shiley mechanical valve, left atrial plication and tricuspid annuloplasty. She fell into low output syndrome on the first postoperative day because of persistent intractable ventricular arrhythmia and eventually required open cardiac massage. The left ventricular (LV) bypass using a centrifugal pump was initiated with cannulation to ascending aorta and left atrium. Echocardiography showed LV wall motion extremely poor with the prosthetic valve being in closed posture. For prevention from thrombus formation on the prosthetic valve and in the LV, a catheter was inserted into LV through RV to give heparin and monitor the LV pressure. As the result, activated clotting time of LV was higher (range from 280-388 sec) than that of systemic blood (range from 182-258 sec). Also, the change of LV pressure was monitored through this LV catheter. Under this monitor, IABP was smoothly applied in the presence of aortic regurgitation, and she was weaned from LV-bypass successfully after 157 hrs support. She was discharge on the 77th postoperative day without thromboembolic complication.

Two hundred forty-four Björk-Shiley Monostrut valves were implanted in 225 consecutive patients from October 1983 to December 1988. Aortic valve replacement was performed in 90 patients, mitral valve replacement in 118, and double valve replacement in 16 patients. One patient had tricuspid valve replacement. There were 100 female patients and 125 male patients with a mean age of 54 years (range 2 to 71 years). Present data were completely available for all patients. The cumulative follow-up was 541 patient-years with a mean of 2 years, 5 months. The closing date for follow-up was July 1989, and the closing interval was 2 months. The early mortality rate was 3.1%, and the late mortality rate, 3.1%. The 5-year survival rate was 88% +/- 2.0%: 87% +/- 3.0% for aortic valve replacement, 91% +/- 3.3% for mitral valve replacement, and 75% +/- 9.6% for double valve replacement. The actuarial rates of freedom from thromboembolism at 5 years were 93% +/- 3.2% for aortic, 96% +/- 1.4% for mitral, and 94% +/- 6.1% for double valve replacement. There were no instances of structural valve deterioration. Actuarial rate of freedom from valve-related morbidity and mortality was 86% +/- 2.0% at 5 years: 86% +/- 9.5% for aortic, 87% +/- 3.3% for mitral, and 75% +/- 7.3% for double valve replacement. Effective valve areas (average) of 12 mitral and 12 aortic valve prostheses were calculated at rest and during bicycle exercise: 2.4 cm2 at rest and 2.8 cm2 during exercise in 27 mm aortic valves, 2.4 cm2 at rest and 3.0 cm2 during exercise in 25 mm aortic valves, 2.0 cm2 at rest and 2.4 cm2 during exercise in 27 mm mitral valves, and 2.6 cm2 at rest and 2.5 cm2 during exercise in 29 mm mitral valve. On the basis of our follow-up period of 5 years, we have judged the Björk-Shiley Monostrut valve reliable, with a low incidence of valve-related morbidity and with acceptably satisfactory hemodynamic characteristics at rest and during exercise.

We tested a new angled transducer developed for intraoperative epicardial echocardiography in 42 patients. This small transducer, 70 x 20 x 15 mm in size, demonstrated superior operability and provided adequate two- or four-chamber imaging from the apical approach, which may lead to high-quality assessment with two-dimensional Doppler flow imaging.

An ultrasonic device in conjunction with open mitral commissurotomy was applied in 8 patients with heavily calcified, stenosed mitral valves. In 6 patients, reconstruction of the mitral valve by debridement of the leaflet calcification with the device was successful. Two patients required valve replacement because of an increase in preexistent mitral regurgitation caused by excessive decalcification. The ultrasonic device proved to be a useful and effective adjunct for salvaging the heavily calcified mitral valve, which would otherwise have to be replaced.

With angiography and pressure measurement, we determined left ventricular volume, wall stress, and systolic performance in 30 patients with aortic regurgitation before and after successful aortic valve replacement. End-systolic wall stress was greatly elevated preoperatively and decreased to normal postoperatively. Systolic pump performance assessed as ejection phase indexes was severely depressed preoperatively and improved to normal or near-normal postoperatively in most patients. The ratio of end-systolic wall stress to end-systolic volume index (ESS/ESVI), an index of myocardial contractility, was greatly decreased before operation. Postoperatively, the ratio increased in all patients, becoming normal in 12 of the 13 patients who had a preoperative ESS/ESVI of 2.9 or greater. However, 15 of 17 patients in whom the ESS/ESVI ratio was less than 2.9 still had subnormal ratios, which indicates the presence of irreversible contractile dysfunction. Stepwise multivariate analysis showed that preoperative ESS/ESVI was the only independent discriminator of postoperative normalization of the contractile function as assessed by ESS/ESVI. After aortic valve replacement, myocardial contractile state does not return to normal in a considerable number of patients. It is important to offer aortic valve replacement for aortic regurgitation before the chance for a good functional result is lost. The ESS/ESVI ratio may be a useful index in determining the timing of operation in patients with aortic regurgitation.

Pre- and postoperative left ventricular (LV) mass and myocardial contractile state were evaluated in 62 patients with aortic regurgitation (AR) and in 20 patients with aortic stenosis (AS). Preoperatively, there was a significant inverse correlation between LV mass and end-systolic wall stress (ESS)/end-systolic volume index in AR patients and AS patients. In patients with preoperative LV mass exceeding 250 g/m2, ejection fraction failed to return to normal postoperatively, despite reduction in ESS close to the normal controls. Our results indicated that myocardial function was irreversible even in postoperative unloading conditions, when preoperative LV mass exceeded 250 g/m2 in AR patients as well as AS patients.

A case is reported here in which segmental autotransplantation of the pancreas was performed after total pancreatectomy for advanced periampullary carcinoma in an attempt to preserve pancreatic endocrine function. The postoperative course was uneventful. The requirement of insulin decreased after the operation and the daily profile examination, done 5 months following surgery, showed a permissive fluctuation of blood sugar levels without insulin injection. Thus, segmental autotransplantation of the pancreas offers a method of preserving pancreatic endocrine function after total pancreatectomy for periampullary carcinoma in selected patients.

We evaluated the long-term (18 years) results of 356 patients undergoing valve replacement with Björk-Shiley valve prosthesis (aortic, 212; mitral 120; double valve, 24) between 1970 and 1988. Actuarial survival rates were 90% (18 years) for AVR, 80% 'years) for MVR and 90% (8 years) for DVR. Actuarial rates of thromboembolism were 99% (18 years) for AVR, 98% (8 years) for MVR and 94% (8 years) for DVR. Actuarial rates of freedom from events (including valve failure, thromboembolism, reoperation and prosthetic valve endocarditis) were 82% (18 years) for AVR, 95% (8 years) and 94% (8 years) for DVR. There were no differences in these results among spherical disc, convexo-concave disc and monostrut valve. In conclusion, this study demonstrated that Björk-Shiley valve showed a low incidence of postoperative events. These results endorse our choice of the Björk-Shiley.