Peripheral pulmonary atelectasis and oxygentation impairment following coronary artery bypass grafting.

BACKGROUND: Severe pulmonary oxygenation impairment occurred in some patients with pleurotomy during the harvest of the internal mammary artery graft followed by coronary artery bypass grafting (CABG). Peripheral pulmonary atelectasis in the postoperative chest X-ray was detected in these patients. We studied the efficacy of intraoperative positive end-expiratory airway pressure (PEEP) therapy for the prevention of postoperative pulmonary oxygenation impairment. METHODS: The pleural cavity was intraoperatively opened in 40 patients with solitary CABG procedure performed during 5 years since January 1992. These patients were divided into two groups. Intraoperative PEEP therapy, which is initiated just after pleurotomy, was not used in 32 patients before May, 1996 (control group) and used for recent 8 patients with pleurotomy (PEEP group). The mean age of patients was 60 years old in the control group and 68 in the PEEP group. RESULTS: Respiratory insufficiency (A-aDO2 >400 mmHg and RI >1.5) was detected in 6 patients in the control group. Three out of these 6 patients required long-term mechanical respiratory support over a week. No respiratory insufficiency occurred in patients of the PEEP group. Values of PaO2, A-aDO2, respiratory index and shunt ratio were significantly worse in the control group than in the PEEP group. CONCLUSIONS: In conclusion, PEEP therapy may prevent pulmonary atelectasis and oxygen impairment after CABG.

Cytokine induction by LVAD in the canine kidney.

BACKGROUND: The outcome of left ventricular assist device (LVAD) support is reported to be associated with proinflammatory cytokines. We investigated the effect of LVAD support on renal function and the resultant cytokine induction. METHODS: A prospective experimental study was performed using 15 mongrel dogs weighing 14 to 36 kg. LVAD was introduced in nine dogs (LVAD group) and the remaining six dogs were managed without LVAD support (control group). All animals were observed for six hours after thoracotomy. Renal regional blood flow was measured, and albumin-creatinine ratio (ACR) and N-acetyl-beta-D-glucoseaminidase index (NAGI) were evaluated as parameters of glomerular and tubular function, respectively. Tumor necrosis factor alpha (TNF-alpha) concentrations in the blood and homogenate of renal tissues were measured and immunohistological examination of renal tissues was conducted by means of anti-nuclear factor kappa B (NF-kappa B), TNF-alpha and interleukin 1 beta (IL- 1 beta) antibodies. RESULTS: In the LVAD group, the renal cortex-medullar blood flow ratio significantly (p<0.05) decreased, and ACR was significantly (p<0.05) higher than in the control group, indicating glomerular insufficiency. There were no significant differences in NAGI and TNF-alpha levels in the blood and renal tissues between the two groups. Immunohistological examination of renal tissues demonstrated an accumulation of NF-kappa B, TNF-alpha, and IL-1 beta in the LVAD group. CONCLUSIONS: An LVAD alters renal regional blood flow and induces a small amount of cytokines. We speculate that if an LVAD is introduced during systemic inflammatory response syndrome, the LVAD will induce a second attack resulting in multiorgan failure. For successful LVAD support, the appropriate selection of time periods is essential.

The effect of Celsior solution on 12-hour cardiac preservation in comparison with University of Wisconsin solution.

BACKGROUND: Celsior is a new extracellular-type preservation solution which has been developed to act not only as a storage medium but also as a perfusion fluid during initial donor heart arrest, poststorage graft reimplantation and early reperfusion. We designed this experimental study to evaluate the effect of the Celsior solution in comparison with the University of Wisconsin solution from the viewpoint of energy depletion. METHODS: Adult mongrel dogs weighing 9 to 13 kg were divided into two groups. In the UW group (n=7), a 4 degrees C University of Wisconsin solution was used for coronary vascular washout and storage following cardiac arrest using a glucose-insulin-potassium solution. In the Celsior group (n=7), the Celsior solution was used to obtain cardiac arrest, coronary vascular washout and storage. High energy phosphate levels and myocardial pH were measured using (31)P-nuclear magnetic resonance spectroscopy immediately after preservation and at 3, 6 and 12 hours after preservation. After 12-hour cold storage, left ventricular free wall tissues were harvested for histological examination. RESULTS: High energy phosphate levels and myocardial pH were significantly better preserved in the Celsior group than in the UW group. In the histological findings, glycogen granules were preserved well in the Celsior group. CONCLUSIONS: We conclude from our study that the Celsior solution is comparable to the University of Wisconsin solution for use in 12-hour heart preservation in canine models.

Cardiac transplantation following a 24-h preservation using a perfusion apparatus.

BACKGROUND: We developed a new apparatus for heart preservation and have already reported successful transplantation following 12 h of preservation using this apparatus. The efficacy of coronary perfusion with an oxygenated Celsior solution was investigated through transplantation following 24 h of preservation using the apparatus. MATERIALS AND METHODS: After being harvested, grafts were preserved with a combination of immersion in a 4 degrees C Celsior solution and perfusion with an oxygenated Celsior solution using the apparatus in the coronary perfusion (CP) group and simply immersed in a 4 degrees C Celsior solution in the simple immersion(SI) group. beta-Adenosine triphosphate (beta-ATP), phosphocreatine (Pcr), and inorganic phosphate (P(i)) levels and myocardial pH (pH(i)) were measured immediately after the heart was excised and at 12 and 24 h after preservation. Following preservation, orthotopic transplantation was performed. Cardiac function was measured 2 h after weaning from cardiopulmonary bypass (CPB). RESULTS: beta-ATP/P(i), Pcr/P(i), and pH(i) levels were significantly higher in the CP group than in the SI group at 12 and 24 h after preservation. Four of six animals in the CP group and two of six in the SI group were successfully weaned from CPB. The recovery rates of cardiac function were better in the CP group than in the SI group. CONCLUSION: Twenty-four hours of heart preservation may be possible with a combination of immersion in a 4 degrees C Celsior solution and perfusion with an oxygenated Celsior solution using the perfusion apparatus.

Growth of the pulmonary arteries after systemic-pulmonary shunt.

Pulmonary artery growth after a systemic-pulmonary shunt was angiographically evaluated in 19 out of 35 patients. The mean age of the subjects at the time of the initial operation was 18+/-18 months including 12 patients under a year old. The preoperative diagnosis was tetralogy of Fallot (TOF) in 10 patients, TOF plus pulmonary atresia in five and transposition of great arteries in four. A Blalock-Taussig shunt (BTS) operation was performed in 16 patients (15 classical and 1 modified) and a central shunt was performed in three patients as an initial operation. The preoperative pulmonary artery index (PAI) was 129+/-42 in all patients and there were no significant differences between patients under or over a year old (139+/-42 vs. 115+/-49). Postoperative angiography was performed 32+/-13 months after the surgery. Room air arterial O2 pressure increased significantly from 29+/-5 mmHg to 42+/-5 mmHg just after an initial palliative shunt operation. PAI change in patients under a year old was 214+/-73%, which was higher than 145+/-27% in patients over a year old after a palliative shunt operation. On the ipsilateral side, PAI change was almost the same between patients under and over a year old. On the contralateral side, PAI change in patients under a year old was 216+/-68%, which was significantly higher than the 116+/-21% in patients over one year old. There was a significant negative correlation (r=-0.65, p<0.05) between PAI change and arterial O2 pressure as measured just after a palliative shunt operation. In conclusion, a palliative shunt operation prior to a year old is desirable in order to produce sufficient and bilateral pulmonary artery growth.

[Right ventricular outflow tract reconstruction using a three-valved extracardiac conduit of expanded polytetrafluoroethylene vessel graft in the Ross operation: a pediatric case report].

A 16-year-old boy was diagnosed as having severe aortic regurgitation and moderate aortic stenosis due to congenital aortic bicuspid valve. A chest X-ray film showed the cardiothoracic ratio (CTR) of 64% and echocardiography revealed severe dilation of the left ventricular dimension with severe wall thickness. An electrocardiogram showed multiple ventricular arrhythmias. The patient underwent the Ross operation with the reconstruction between the right ventricle and the pulmonary arteries using a three-valved conduit which was made by an expanded polytetrafuloroethylene vessel graft. Ventricular arrhythmia disappeared just after the operation and left ventricular dimensions improved with the CTR of 53% except mild regurgitation of the neo-aortic valve three months later.

FK409 ameliorates ischemia-reperfusion injury in heart transplantation following 12-hour cold preservation.

OBJECTIVE: FK409 is the first spontaneous nitric oxide donor to increase plasma guanosine 3':5'-cyclic monophosphate. We designed this study to investigate whether the administration of FK409 during reperfusion ameliorated ischemia-reperfusion injury and enhanced post-transplant graft function in orthotopic heart transplantation following 12-hour cold preservation in a canine model. METHODS: We used 10 pairs of adult mongrel dogs, weighing 9.5 to 13.5 kg. Following cardiac arrest using cardioplegia, we washed out the coronary vascular beds with cold University of Wisconsin solution followed by 12-hour preservation. After preservation, we performed orthotopic transplantation. The experimental animals were divided into 2 groups. In the FK group (n = 5), FK409 (5 microg/kg/min) was administered intravenously, beginning 15 minutes before the onset of reperfusion and continuing for 45 minutes after reperfusion. In the control group (n = 5), saline vehicle was administered in the same manner. Two hours after transplantation, we assessed cardiac function, including cardiac output, left ventricular systolic pressure (LVP), and the maximum rates of positive and negative increase of LVP (+/-LV dP/dt) by comparing the recovery rate (%) of the cardiac function of the donor animal. We measured endothelin-1 levels in blood obtained from a catheter inserted into the coronary sinus 30, 60, and 120 minutes after reperfusion. RESULTS: Cardiac output was higher in the FK group than in the control group, but the difference was not significant (p = 0.08). Left ventricular systolic pressure and +/-LV dP/dt were significantly (p < 0.05) higher in the FK group than in the control group. Endothelin-1 levels were significantly (p < 0.05) lower in the FK group than in the control group 30 minutes after reperfusion. Transmission electron microscopy showed that the basal lamina of capillary vessels, glycogen granules, and mitochondrial structure were well-preserved in the FK group. CONCLUSIONS: In orthotopic transplantation models, FK409 is effective in ameliorating ischemia-reperfusion injury following preservation and in enhancing post-transplant cardiac function.

A comparative study of Celsior and University of Wisconsin solutions based on 12-hr preservation followed by transplantation in canine models.

BACKGROUND: Celsior is a recently developed extracellular-type preservation solution that is effective in organ preservation. This experimental study was designed to compare the effects of Celsior and University of Wisconsin (UW) solutions in myocardial protection, using 12-hour preservation followed by orthotopic transplantation. METHODS: Fourteen pairs of adult mongrel dogs were divided into 2 groups. In the UW group (n = 7), UW solution at 4 degrees C was used for coronary vascular washout and storage following cardiac arrest with glucose-insulin-potassium (GIK) solution. In the Celsior group (n = 7), Celsior solution was used to produce cardiac arrest, for coronary vascular washout, and for storage. After 12-hour cold preservation, orthotopic transplantation was performed under cardiopulmonary bypass (CPB). The rate of recovery (%) of cardiac function of donor hearts was compared 1 and 2 hours after weaning from CPB, and then the transplanted hearts were harvested for histological study. RESULTS: Hemodynamic parameters including cardiac output, left ventricular pressure (LVP), and the maximum rates of positive and negative increase of LVP after transplantation were significantly (p < 0.05) higher in the Celsior group than in the UW group 2 hours after weaning from CPB. The transmission electron microscopic study found that degeneration of the mitochondria in the Celsior group was less extensive than in the UW group. CONCLUSION: Celsior solution enhanced the cardiac function of hearts preserved for 12 hours prior to transplantation compared to UW solution. Our results indicate that Celsior solution is equivalent or superior to UW solution for cardiac preservation.

The Effect of FR167653 on Cerebral Ischemia-Reperfusion Injury After Retrograde Cerebral Perfusion in a Canine Model.

Retrograde cerebral perfusion (RCP) has recently been reported to be useful for the repair of aortic arch aneurysms. However, there is a possibility that RCP supplies a limited amount of blood to the brain [1] and ischemia-reperfusion injury may occur after RCP. FR167653 (FR) is characterized as a potent suppressant of interleukin-1beta and tumor necrosis factor-alpha. We investigated the role of FR in preventing cerebral ischemia-reperfusion injury after RCP in a canine model. A total of 12 mongrel dogs was divided into two groups: in the FR group (n = 6), FR167653 (1 mg/kg/hour) was continuously administered during the period of RCP and rewarming; in the control group (n = 6), a physiological saline solution was administered at the same dosage as the FR167653 during the same period. Following hypothermia (20 degrees C) using cardiopulmonary bypass and circulatory arrest, RCP was performed by infusing oxygenated blood via the bilateral internal maxillary veins for 60 minutes at a perfusion pressure of 25 mmHg. The cerebral blood flow (CBF), cerebral metabolic rate for glucose (CMRGlu) and oxygen (CMRO2), and excretion of carbon dioxide (ExCO2) were measured. These results were expressed as the percentage of change from baseline values established immediately after anesthesia. CBF was significantly (p < 0.05) higher in the FR group than in the control group at 40 (159 +/- 25% and 82 +/- 21%, respectively) and 60 minutes (177 +/- 30% and 83 +/- 14%, respectively) after RCP. The lactate/pyruvate ratio of blood returned from the brain tissues was significantly (p < 0.05) lower in the FR group than in the control group at 40 and 60 minutes after RCP. CMRGlu was significantly (p < 0.05) higher in the FR group than in the control group 60 minutes after RCP. There was no significant difference in CMRO2 and ExCO2 between the two groups. It is concluded that FR167653 appears to be effective in protecting the brain from ischemia-reperfusion injury after RCP.http://link.springer-ny.com/link/service/journals/00547/bibs/8n3p143.html

Long-term heart preservation using a new portable hypothermic perfusion apparatus.

OBJECTIVE: Perfusion storage is not often used clinically compared with simple immersion because of complicated circuits and demanding management. We developed a new apparatus for preservation combined with simple immersion and continuous coronary perfusion. METHODS: The main characteristics of this apparatus are as follows: (1) hypothermic storage, (2) does not require any energy source, (3) variable perfusion pressure, and (4) portability. The perfusion apparatus is composed of a storage chamber, a cooling chamber, and metal bars from which a perfusate bag is suspended. Adult mongrel dogs were divided into two groups: the coronary perfusion group (CP, n = 6) and the simple immersion group (SI, n = 6). Coronary vascular beds of the dog were washed out with a University of Wisconsin (UW) solution following cardiac arrest obtained using a GIK solution. The hearts were then excised. In the CP group, the heart graft, which was immersed in a 4 degrees C UW solution, was perfused with the same solution at a flow rate of 35 approximately 50 ml/hr. In the SI group, the heart graft was immersed in a 4 degrees C UW solution only. The heart graft was preserved for 12 hours in both groups. Beta-adenosine triphosphate (beta-ATP), phosphocreatine (Pcr), and inorganic phosphate (Pi) levels were measured immediately after excision of the heart, and at 3, 6, and 12 hours after preservation. Beta-ATP, Pcr, and Pi values were expressed as a percentage of control values, which had been obtained immediately after excision of the heart. Water content of the myocardium was measured prior to and after 12-hour preservation. The preserved graft was then evaluated through orthotopic transplantation. RESULTS: Beta-ATP/Pi levels at 6 and 12 hours after preservation were significantly higher in the CP group than in the SI group (62 +/- 5 versus 39 +/- 7%, 48 +/- 5 versus 22 +/- 8%, respectively, p < 0.05). Pcr/Pi levels at 6 and 12 hours after preservation were 30 +/- 9% and 22 +/- 8%, respectively in the CP group, while Pcr/Pi levels in the SI group were detected in only one case. There was no significant difference in water content either prior to or after 12-hour preservation between the two groups. Histopathologically, irregular expansion and/or contraction of myocardial fibers were more severe in the SI group than in the CP group. The recovery rate of hemodynamic parameters 2 hours after heart transplantation was significantly (p < 0.05) higher in the CP group than in the SI group. CONCLUSION: Stable and safe long-term canine heart preservation with continuous coronary perfusion associated with immersion is possible using this new apparatus, and may have broad clinical application.

Assessment of the myocardial protective effect of antegrade warm blood cardioplegia by measuring the release of biochemical markers.

Intermittent warm blood cardioplegia has been reported as a valuable alternative for myocardial protection in cardiac surgery; however, conflicting experimental data have been published. To assess the clinical effectiveness of intermittent warm cardioplegia, we measured the release of troponin-T (Tn-T), a highly sensitive and specific marker of myocardial damage, and creatine kinase MB isoenzyme (CK-MB), in 12 patients who underwent elective coronary artery bypass grafting (CABG) with antegrade intermittent warm blood cardioplegia (37 degrees C) being the warm group, in comparison with 16 patients who underwent CABG with antegrade intermittent cold blood cardioplegia (4 degrees C) being the cold group. Blood samples were taken to determine the serum concentrations of CK-MB and Tn-T, at the induction of anesthesia, then 3, 6, 12, and 24h after the termination of cardiopulmonary bypass (CPB). The peak increase in serum CK-MB levels, 3h after CPB, was significantly lower in the warm group than in the cold group, at 27.8+/-7.8 IU/l vs. 40.8+/-12.6 IU/l, respectively (P = 0.0042). The serum Tn-T 12 h after CPB was significantly lower in the warm group than in the cold group, at 1.40+/-0.71 ng/ml vs. 2.06+/-0.95 ng/ml, respectively (P = 0.049). In conclusion, intermittent antegrade warm blood cardioplegia showed effective myocardial protection in elective CABG.

Hemodynamic effects of alpha-human atrial natriuretic polypeptide on patients undergoing open-heart surgery.

BACKGROUND: A cardiac hormone, alpha-human atrial natriuretic polypeptide (alpha-hANP), acts as a vasodilator and a diuretic by activating cyclic GMP formation. We studied the hemodynamic effects of continuous intravenous infusion of alpha-hANP on patients undergoing open-heart surgery. METHODS: A total of 15 patients, including 7 with CABG, 4 with AVR, 2 with CABG plus AVR, and 2 with AVR plus MVR were involved in the study. They underwent open-heart surgery in our institute between July 1996 and April 1997. The mean age of patients was 68 years, ranging from 63 to 77. A dosage of 0.05 microg/kg/min of alpha-hANP was administered to all patients on postoperative day 1. Hemodynamics and blood and urine samples were measured at the following times: 2 hours before continuous intravenous infusion of alpha-hANP, 0, 1, 2, 3, 6, 12 and 24 hours after continuous intravenous infusion. We concomitantly measured urine volume and the plasma concentration of alpha-hANP. RESULTS: The plasma concentration of alpha-hANP increased sufficiently after the beginning of continuous intravenous infusion without any side effects, and the urine volume increased too. The administration of alpha-hANP induced a decrease in central venous pressure, pulmonary capillary wedged pressure and the pulmonary vascular resistance index. Systemic vascular resistance index and cardiac output remained unchanged. CONCLUSIONS: It is useful for the management of patients with associated volume overload following open-heart surgery because the administration of alpha-hANP decreases preload and facilitates satisfactory urination.

Prenatally diagnosed cystic lymphangioma in infants.

BACKGROUND/PURPOSE: Prenatally diagnosed cystic lymphangioma (CL) is often associated with chromosomal anomalies, hydrops fetalis, and, in the case of cervical CL, occasionally respiratory distress just after birth. Often it is difficult to treat prenatally diagnosed CL because of the large size and associated symptoms. METHODS: Between 1988 and 1997, 11 cases of prenatally diagnosed CL were treated. Five pregnancies were terminated electively and one aborted spontaneously (nondelivered, non-D group), and another five delivered (delivered, D group). Thirteen infants nondiagnosed prenatally were also seen in the same period (prenatally nondiagnosed, without pre-D group). RESULTS: In the non-D group, massive CLs were diagnosed by ultrasound scan between 16 and 20 weeks' gestation. They occurred in the head and neck in all six cases, and four had associated pleural effusions or hydrops. In the D group, CL occurred in the face and neck in four cases. Three were born by cesarean section with neonatologists and surgeons standing by, then transferred to our hospital immediately after birth. Respiratory distress appeared in two cases; tracheostomy was carried out in one case. One patient with a huge CL in the chest and abdominal wall necessitated partial resection after OK-432 sclerotherapy. In the without pre-D group, there was CL in the face or neck in 10 cases, abdominal wall in two cases, and chest wall in one case. Respiratory distress was observed in three cases of cervical CL, and tracheostomy was required in two cases. One patient with hypoxic brain damage sequela died of pneumonia afterward. CONCLUSIONS: Prenatal diagnosis permits planned delivery, prompt postnatal resuscitation, and improve prognosis. Infants with massive CL diagnosed early in pregnancy have other associated anomalies as well as hydrops fetalis, and a poor outcome or difficult management can be expected.