Mild mitral regurgitation was associated with increased prevalence of thromboembolic events in patients with nonrheumatic atrial fibrillation

Although several studies demonstrated that the presence of significant mitral regurgitation was associated with reduced occurrence of thromboembolism, little data is available concerning the effect of mild mitral regurgitation on the occurrence of thromboembolic events. To evaluate the association between mild mitral regurgitation and thromboembolic events, we reviewed 232 patients' records between January 1996 and September 1997 who had nonrheumatic atrial fibrillation. There were 59 patients (25%) with mitral regurgitation > or = grade 2, 69 patients (30%) with grade 1 mitral regurgitation, and 104 patients (45%) with no mitral regurgitation. Patients with grade 1 mitral regurgitation had significantly higher prevalence of thromboembolic events (28%) than those with mitral regurgitation > or = grade 2 (8%, P=0.006) or those with no mitral regurgitation (11%, P=0.007). A history of previous thromboembolic events were compared between 173 patients with grade 1 mitral regurgitation and those with no mitral regurgitation using the logistic regression analysis adjusted for age, sex, administration of warfarin, and presence of hypertension, diabetes mellitus, structural heart disease, enlarged left atrium (> or = 40 mm), chronic atrial fibrillation, and grade 1 mitral regurgitation. Grade 1 mitral regurgitation (odds ratio=2.689, 95% confidence interval=1.039-7.189, P=0.0434) and no warfarin administration (odds ratio=0.045, 95% confidence interval=0.002-0.242, P=0.0036) were significantly associated with the history of thromboembolic events. The presence of mild mitral regurgitation in nonrheumatic atrial fibrillation was associated with higher prevalence of thromboembolic events.

Sorption of arsenate and arsenite anions by iron(III)-poly(hydroxamic acid) complex

Iron(III)-poly(hydroxamic acid) resin complex has been studied for its sorption abilities with respect to arsenate and arsenite anions from an aqueous solution. The complex was found effective in removing the arsenate anion in the pH range of 2.0 to 5.5. The maximum sorption capacity was found to be 1.15 mmol/g. The sorption selectivity showed that arsenate sorption was not affected by chloride, nitrate and sulphate. The resin was tested and found effective for removal of arsenic ions from industrial wastewater samples.

Heart rate variability and left ventricular dilatation early after myocardial infarction

To assess clinically whether alterations of autonomic tone precede left ventricular dilatation, heart rate variability and early left ventricular dilatation after a first myocardial infarction were assessed. Low-frequency power (LF), high-frequency power (HF), and total power (TP) were obtained by ambulatory electrocardiogram on day 1 in 53 patients with a first acute myocardial infarction. Left ventricular end-diastolic volume determined by echocardiography was obtained on day 1 and day 14. Stepwise linear regression analysis was used to assess the associations of early left ventricular dilatation with heart rate variability adjusted for clinical variables. Higher LF and TP were significantly associated with early left ventricular dilatation after adjustment for age, sex, site of myocardial infarction, acute revasucularization, peak creatine kinase level, history of hypertension, and use of angiotensin-converting enzyme inhibitors and beta-blockers. Higher LF and TP preceded early left ventricular dilatation after myocardial infarction.

Long-term administration of atrial natriuretic peptide in patients with acute heart failure

A short-term treatment of atrial natriuretic peptide (ANP), a circulating hormone of cardiac origin, is reported to improve cardiac performance in patients with chronic heart failure. However, clinical usefulness of long-term administration of ANP in patients with congestive heart failure has not been reported. We studied 36 patients with severe acute heart failure who resisted various therapy. Hemodynamic parameters were measured before and 48 h after initiating ANP infusion (n = 18) or normal saline (n = 18). Mean pulmonary capillary wedge pressure (23-->13 mm Hg), mean right atrial pressure (10-->5 mm Hg), systemic vascular resistance (2,169-->1,307 dyn x s x cm(-5)) and pulmonary vascular resistance (318-->136 dyn x s x cm(-5)) decreased significantly, whereas cardiac index (1.9-->2.6 L/min/m2) and urine volume (1,692-->2,560 ml/day) increased during long-term ANP infusion (before-->48 h). Moreover, in eight patients with long-term ANP infusion, these hemodynamic effects were maintained at 7 days after initiating ANP infusion. Vasodilating, pulmonary vasorelaxant, and diuretic activities of ANP are maintained without tolerance, and thus long-term ANP infusion is clinically useful in patients with severe acute heart failure.

[Association between the results of blood test and blood PCB level of chronic Yusho patients twenty five years after the outbreak]

A cross-sectional study on the association between the results of blood test and the blood concentration of PCB was conducted on the chronic Yusho patients. The subjects were 265 Yusho patients (134 men and 131 women) who received the annual nationwide health examination for Yusho in 1993. The results of the blood test and questionnaire survey at the annual health examination were used for the analyses using ANCOVA. Serum levels of triglycerides, total cholesterol, GOT, GPT, gamma-GTP, total bilirubin, and conjugated bilirubin were associated with the blood concentration of PCB adjusting for sex, age, drinking habit, smoking habit and body mass index (BMI). Because the distribution of the serum levels was strongly skewed to the right except that of serum concentration of total cholesterol, they were log transformed to approximate to the Normal distribution. The association between age and the blood concentration of PCB was significant (P < 0.001), although the associations of sex, drinking habit, smoking habit and BMI to the blood concentration of PCB were not significant. With the adjustment for sex, age, drinking habit, smoking habit and BMI, the serum concentrations of triglycerides and total cholesterol were significantly associated with the blood PCB level expressed by loge (blood concentration of PCB in ppb-1) (P = 0.02 and P < 0.001, respectively). The associations of serum levels of GOT, GPT, gamma-GTP, total bilirubin and conjugated bilirubin to the PCB level were not significant. The results of this study suggests the need of careful observation on the serum lipids of Yusho patients, especially those with high concentration of blood PCB, because the serum concentrations of total cholesterol and triglycerides are prominent risk factors of heart diseases.

Higher heart rate variability of smokers after acute myocardial infarction

Although cigarette smoking is known to be a strong risk factor for the development of coronary artery disease, several large clinical studies have demonstrated that current smokers had a favorable prognosis compared to nonsmokers after myocardial infarction. This study sought to evaluate the effect of smoking status on heart rate variability after onset of acute myocardial infarction. We studied 52 patients (34 smokers, 18 nonsmokers) with a first myocardial infarction within 24 h of onset. We recorded 24-h ambulatory ECG to calculate very low frequency power (VLF), low frequency power (LF) and high frequency power (HF) 14 days after onset. Although smokers had a tendency to be younger than nonsmokers (mean age 57 versus 62, P = 0.0812), clinical characteristics were not statistically different between smokers and nonsmokers. After adjustment for age, left ventricular ejection fraction, history of diabetes, acute revascularization and use of beta-blockers, VLF (P = 0.0183) of smokers 14 days after onset was significantly higher than for nonsmokers. In conclusion, although smoking reduces heart rate variability in the general population, higher heart rate variability was observed in smokers than nonsmokers after acute myocardial infarction under the condition of smoking cessation.

Efficacy of extracorporeal ultrafiltration of ascitic fluid as a treatment of refractory ascites

BACKGROUND

Refractory ascites is recognized in patients with various conditions. Although intravenous reinjection of ascitic fluid after its filtration and concentration (IRA) is an effective method of treating this condition, many associated side-effects have been reported. We performed extracorporeal ultrafiltration of ascitic fluid (EUA) to demonstrate the efficacy and advantages of this method of treating refractory ascites.

METHODS

EUA was performed in seven patients with hepatic cirrhosis (3 cases), lupus nephritis, diabetic nephropathy, and carcinomatous peritonitis (2 cases) for a total of 122 sessions. IRA was performed in three of these seven patients for a total of 12 sessions.

RESULTS

The average volumes of ascitic fluid removed by EUA and IRA were 3.94+/-1.45 litres and 2.87+/-0.69 litres (mean+/-SD) respectively. Although chills and acute renal failure were recognized as complications of IRA in five and one sessions respectively, the only complication of EUA was severe intra-abdominal haemorrhage, which resolved spontaneously. In spite of rapid and massive removal of ascitic fluid (maximum 2.0 litres per 15 min), significant changes in blood pressure were not noted during EUA. In three patients (hepatic cirrhosis, lupus nephritis, and diabetic nephropathy), de novo production of ascitic fluid disappeared. In one patient with hepatic cirrhosis and chronic renal failure on haemodialysis, 67 sessions of EUA have been performed under stable conditions. Three patients (one case of hepatic cirrhosis and two cases of carcinomatous peritonitis) died of their primary diseases.

CONCLUSIONS

We conclude that EUA is a useful method for the treatment of massive refractory ascites.

Thrombelastographic changes and early rebleeding in cirrhotic patients with variceal bleeding

BACKGROUND

Routine coagulation tests do not necessarily reflect haemostasis in vivo in cirrhotic patients, particularly those who have bleeding varices. Thrombelastography (TEG) can provide a global assessment of haemostatic function from initial clot formation to clot dissolution.

AIM

To evaluate TEG changes in cirrhotic patients with variceal bleeding and their association with early rebleeding.

PATIENTS/METHODS

Twenty cirrhotic patients with active variceal bleeding had serial TEG and routine coagulation tests daily for seven days. The TEG variables before the day of rebleeding (n = 6) were compared with those of patients without rebleeding (n = 14).

RESULTS

Baseline characteristics of the rebleeding and non-rebleeding groups were comparable apart from a higher incidence of uncontrolled infection on the day of rebleeding in the rebleeding group (p = 0.007). The patients in the rebleeding group were more hypocoagulable before the day of rebleeding as shown by longer r (42 v 24 mm, p < 0.001) and k (48 v 13 mm, p < 0.001) and smaller a (12 v 38 degrees, p < 0.001) compared with the mean of daily results of the non-rebleeding group. Routine coagulation tests, however, showed no significant differences between the two groups.

CONCLUSION

The results of serial TEG measurements suggest that hypocoagulability may be associated with early rebleeding in cirrhotic patients.

Coffee consumption and decreased serum gamma-glutamyltransferase and aminotransferase activities among male alcohol drinkers

BACKGROUND

Attention has long been drawn to the potentially harmful effects of coffee on health, however recent epidemiological studies have suggested unexpected, possibly beneficial effects of coffee against the occurrence of alcoholic liver cirrhosis and upon serum liver enzyme levels.

METHODS

We examined the potential inverse association between coffee drinking and serum concentrations of gamma-glutamyltransferase (GGT) and aminotransferases, with special reference to interaction with alcohol consumption, in a cross-sectional study involving 12687 health examinees (7398 men and 5289 women) aged 40-69 years from over 1000 workplaces in Nagano prefecture in central Japan. Those who had a history of liver disease and/or serum aminotransferases exceeding the normal range were excluded. Possible confounding effects of alcohol consumption, body mass index, cigarette smoking, and green tea consumption were controlled through multivariate analyses.

RESULTS

Increased coffee consumption was strongly and independently associated with decreased GGT activity among males (P trend < 0.0001); the inverse association between coffee and serum GGT was more evident among heavier alcohol consumers (P < 0.0001), and was absent among non-alcohol drinkers. Among females, however, coffee was only weakly related to lower GGT level. Similar inverse associations with coffee and interactions between coffee and alcohol intake were observed for serum aspartate aminotransferase and alanine aminotransferase. Intake of green tea, another popular source of caffeine in Japan, did not materially influence the liver enzyme levels.

CONCLUSIONS

Our results suggest that coffee may inhibit the induction of GGT in the liver by alcohol consumption, and may possibly protect against liver cell damage due to alcohol.

Mechanism of abrupt hypotension with stretch of right atrium during cardiac surgery

During cardiac surgery abrupt hypotension sometimes occurs by the atrium being pulled, though the hypotensive mechanism is not known. The effects of mechanical stretching of the right atrium on haemodynamics and renal sympathetic nerve activity in the anesthetized rabbit was investigated. During stretching of the right atrial appendage with a metal weight (right atrial stretch), both mean arterial pressure (mAP) and renal sympathetic nerve activity significantly decreased. Bilateral vagotomy significantly reduced the change in mean arterial pressure with right atrial stretch (P < 0.01), and significantly increased renal sympathetic nerve activity (P < 0.01). The duration of the decreases of mean arterial pressure with right atrial stretch was significantly shortened after vagotomy. Decreases of blood flow of the descending aorta with right atrial stretch were observed and not affected by vagotomy. These results suggest that hypotension with mechanical stimulation of the right atrium is not only due to the decrease in cardiac output but also to sympathetic inhibition through the vagus via cardiac baroreflex.

Anticipation of job loss or job change and cardiovascular risk factors: a study of retiring self-defense officials in Japan

Self-defense officials in Japan are to retire at the age of early 50s. This unique situation prompted the authors to investigate whether preexisting morbid conditions cause any difficulty in finding a post-retirement job and whether anticipation of job loss or job change, as measured by the status of post-retirement job and months remaining until retirement, was related to biological cardiovascular risk factors. The subjects were 2,228 male self-defense officials who received a preretirement health examination at three Self-Defense Forces Hospitals from 1991 to 1992; the period in time remaining until retirement ranged from 1-40 months (median 12 months), and 62% had one year or less until the retirement. The defined preexisting illnesses included a wide range of chronic, non-communicable diseases. Overall, the preexisting illness was unrelated to the determination of a post-retirement job. In men having 6 months or less until retirement, however, the security of post-retirement job was less frequent when they had the preexisting illness, especially cardiovascular diseases. In 1,839 men excluding those with the preexisting illness, the period until retirement was not adversely related to obesity, blood pressure, serum lipids, serum uric acid, or glucose intolerance whether the post-retirement job had been secured or not. The findings suggest that the preexisting illness decreases the chance of obtaining a post-retirement job, but do not provide any evidence that anticipation of job loss or job change due to early retirement exerts an adverse effect on biological cardiovascular risk factors.

[Symptoms and blood PCB level among chronic Yusho patients, twenty-five years after outbreak]

To investigate the frequency of symptoms and signs and their relationships with blood PCB (polychlorinated biphenyls) levels, twenty-five years after outbreak, we analyzed the data of 276 Yusho patients (male/female: 137/139) who had received health examination in 1993. For this purpose, 31 examination items which correspond or relate to the diagnostic criteria for Yusho (1976) were selected from the examination form. Mean blood PCB concentration in the subjects was 4.69 ppb with the highest value of 31.0 ppb (median : 4.0 ppb). The symptoms for which the proportion exceeded 60% were general fatigue, headache and numbness in extremities. Chronic bronchitis-like symptoms, such as cough and sputum, were observed in 50% of the subjects. Next, the subjects were classified into approximate quartiles of blood PCB: < 3.00, 3.00-4.06, 4.07-5.99, and 6.00+ppb. The distributions of subjects at four levels of blood PCBs were compared between the groups with or without each symptom or sign, using the Cochran-Mantel-Haenszel test. Significant differences were observed for comedones in the trunk (P = 0.02) and other regions (P = 0.02); acneiform eruptions in the genital regions (P = 0.01) and gluteal regions (P = 0.01); and hypersecretion in the Meibomian gland (P = 0.04). Thus, the typical skin and eye symptoms in Yusho patients still persist showing a close relation with blood PCB concentration.

Association of preceding angina with in-hospital life-threatening ventricular tachyarrhythmias and late potentials in patients with a first acute myocardial infarction

We studied 140 patients with a first acute myocardial infarction to examine the effect of preceding angina as a marker of ischemic preconditioning on clinical ventricular arrhythmias and late potentials. Preceding angina was defined as the presence of ischemic chest pain within 24 hours before onset of myocardial infarction lasting no longer than 30 minutes and seen three or more times per day or at rest. Clinical features, angiographic findings, and late potentials were compared between patients with and without preceding angina. Thirty-four (24%) patients had preceding angina. Although the incidence of life-threatening ventricular tachyarrhythmias significantly differed (p = 0.0219), other clinical findings, including presence of late potentials, were not different between the two groups. Of 14 patients with life-threatening ventricular tachyarrhythmias, five events were considered as reperfusion arrhythmias. In patients who had successful reperfusion therapy, the incidence of life-threatening ventricular tachyarrhythmias had a tendency to be lower in patients with preceding angina than in those without preceding angina (p = 0.0586). Severe angina within 24 hours of onset of acute myocardial infarction is suggested to reduce occurrence of life-threatening ventricular tachyarrhythmias mainly associated with reperfusion during hospitalization.

Protein-binding high-performance frontal analysis of (R)- and (S)-warfarin on HSA with and without phenylbutazone

Applicability of high-performance frontal analysis (HPFA) to the stereoselective study of drug-drug interaction upon plasma protein binding has been investigated. Racemic warfarin and phenylbutazone were used as model drugs. An on-line HPFA/HPLC system consisting of a HPFA column (diol-silica column), an extraction column, and a chiral separation column was developed, and human serum albumin solution containing racemic warfarin and/or phenylbutazone was injected directly to the HPFA column. When the injection volume was large enough, the binding equilibrium in the sample solution was reproduced in the column, and consequently a plateau region appeared on the chromatogram. This plateau region contains unbound drug(s). A given volume of eluent in the plateau part was transferred into the extraction column by column-switching. The concentrated drug(s) was then transferred to the chiral separation column to determine the unbound concentrations of the enantiomers and/or the competitor. The results agreed with those obtained by a conventional ultrafiltration-HPLC method. The influence of phenylbutazone upon the protein binding of warfarin is enantioselective. In warfarin and human serum albumin mixed solution, the unbound concentration of (R)-warfarin was 1.22 times higher than that of the S-isomer. By addition of phenylbutazone, the unbound concentration of (S)-warfarin increased more than that of (R)-warfarin, resulting in the reversed enantioselectivity, i.e., the unbound concentration of (S)-warfarin became 1.19 times larger than that of (R)-warfarin. The present method was also applicable to human plasma samples.

Experimental study of ascending Candida albicans pyelonephritis focusing on the hyphal form and oxidant injury

To investigate the pathogenicity of the hyphal form of Candida in pyelonephritis a Candida albicans strain, assuming only the yeast form but not the hyphal form when induced by ultraviolet mutagenesis, and a revertant strain from this mutant strain showing bimorphism were compared in a rat experimental model with regard to the incidence of ascending Candida pyelonephritis and the grade of inflammation. To increase the frequency of pyelonephritis unilateral incomplete ureteral stenosis was created. The revertant strain assuming the hyphal form showed a significantly (p < 0.01) higher frequency of pyelonephritis as compared with the mutant strain not assuming this form, and the grade of inflammation was also higher in the revertant strain group. Also, higher renal tissue and serum levels of both lipid peroxide and superoxide dismutase, which are related to marked renal oxidant injury, tended to be correlated with the degree of neutrophil infiltration in the acute phase. These findings suggest that the hyphal form plays an important role in the development of C. albicans pyelonephritis and also that the oxygen radicals from neutrophils appearing at the sites of inflammation play a major part in the further extension of inflammatory lesions.

[Questionnaire of cryopreserved allograft valves in Kyushu and Yamaguchi area]

Japanese Society of Cryopreserved Thoracic Tissue Implantation was recently set up. Cryopreserved allograft valves are about to pervade in Japan. To clarify the interest, demands and supply of cryopreserved allograft valve in the area of Kyushu and Yamaguchi, we performed questionnaire investigation regarding this issue. Collection rate of this questionnaire was 87.5% (35/40 hospitals). Ninety-seven percent of the hospitals answered that they were interested in cryopreserved allograft. Ninety-four percent of the hospitals answered that they did not ethically hesitate to use cryopreserved allograft. Ninety-one percent of the hospitals hoped to perform cardiac surgery using allograft aortic valve if allograft is available. With respect to securing donors of allograft, two-third of the hospitals did not decide whether they could be involved in obtaining donors of allograft. As the number of the cadaver kidney donors is about 20 per year in the area of Kyushu and Yamaguchi, shortage of donors of allograft valve is anticipated.

Ventilatory responses to CO2: constant fraction vs. constant inflow administration

The purpose of this study was to determine whether the transfer function characteristics of the respiratory CO2 control system differs according to whether the CO2 administration method is constant fraction (CF) or constant inflow (CFlow). Ventilatory responses to CO2 changes were measured in seven healthy subjects during random PETCO2 perturbation by the CF and CFlow administration methods in normoxia and hyperoxia. The transfer function from PCO2 to VE was estimated in the frequency domain from 0.002 to 0.02 Hz. The transfer function characteristics showed a low-pass filter character in both of CFlow and CF. The impulse responses to both the methods persisted for > or = 60 sec, while the maximum amplitude (hmax) of the CFlow response was statistically greater than that of the CF response in normoxic condition. The time required until the peak (tmax) of the CFlow impulse response was shorter than that of CF in normoxia. Hyperoxia retarded the tmax and reduced hmax in both CFlow and CF, with the result that significant differences in the normoxic impulse responses were not observed between CFlow and CF in hyperoxia. To characterize the CO2 control system quantitatively, we determined the static transfer gain, oscillatory frequency, damping factor, and pure time delay by applying a second-order delay model to the observed transfer function. The static gain was not significantly different between CFlow and CF responses in both normoxia and hyperoxia. The pure time delay and damping factor were significantly decreased for CFlow only in normoxia. We suggest that inhalation of CO2 by CFlow modifies ventilatory response, probably mediating through the peripheral chemoreceptor activity.

[Squamous cell carcinoma of the renal pelvis associated with renal stones in a patient with chronic renal failure: a case report and a review of the Japanese literature]

A case of squamous cell carcinoma of the left renal pelvis associated with chronic renal failure on hemodialysis is reported. The patient, a 59-year-old man, had undergone bilateral nephrolithotomy, in 1966, followed by right ureterolithotomy and bilateral percutaneous nephrolithotripsy, but residual stones existed. He suffered from left flak pain and fever, and computed tomography (CT) and magnetic resonance imaging (MRI) revealed left perirenal abscess in July 1994. Percutaneous drainage and antibacterial chemotherapy were performed, but his symptoms did not improve. Three months later, CT and MRI revealed a mass in the left perirenal space and destruction of the 12th thoracic vertebra, which were considered to be infectious changes. On November 9, 1994, left nephrectomy was performed. Histopathological diagnosis was moderately differentiated squamous cell carcinoma, grade 2, INF-gamma, pT4, pR1, pL0 and pV1. In spite of irradiation therapy, he died on January 19, 1995.

Effects of hypothermia during cardiopulmonary bypass and circulatory arrest on sympathetic nerve activity in rabbits

OBJECTIVES

Little is known about the effect of hypothermia on neural regulation. We investigated the effects of hypothermia during cardiopulmonary bypass (CPB) on control of renal (RSNA) and lumbar sympathetic nerve activity (LSNA), and plasma catecholamine levels.

METHODS

We directly measured RSNA (n = 14) and LSNA (n = 6) during CPB in anesthetized rabbits. CPB was performed via cannulae in the aortic root for arterial perfusion and the right atrium for venous drainage. Systemic hypothermia was induced by core cooling. RSNA and LSNA were recorded at the nasopharyngeal temperature of 37, 30, 24, and 18 degrees C and after rewarming up to 37 degrees C while keeping mean arterial pressure at 70 mmHg by altering perfusion flow. Other variables such as blood gases or electrolytes were kept constant.

RESULTS

RSNA at the temperature of 30, 24, and 18 degrees C significantly decreased by 91, 97, and 95% from control (37 degrees C), respectively. LSNA decreased by 18, 57, and 89% from control as well. The decreases in RSNA at 30 and 24 degrees C were greater than those in LSNA (P < 0.05). At 18 degrees C both RSNA and LSNA nearly disappeared. Circulatory arrest for 20 min during hypothermia at 18 degrees C caused no increase in RSNA while it increased LSNA. Plasma catecholamine levels at 18 degrees C were not different from those at 37 degrees C. Rewarming to 37 degrees C increased RSNA and LSNA by 321 and 92% from control (37 degrees C before cooling), respectively (P < 0.01).

CONCLUSIONS

Hypothermia progressively decreased and rewarming markedly increased sympathetic nerve activity, but the effects of hypothermia on RSNA and LSNA were not uniform.

[The perinatal risk factors and periventricular leukomalacia (PVL) in premature infants--relationship between fetal heart rate decelerations and PVL]

Periventricular leukomalacia (PVL) has recently been recognized as an important risk factor of neurological impairment in premature infants. We studied 29 PVL cases on perinatal risk factors comparing with a non-PVL matched control group retrospectively. Variable decelerations were more frequently observed with statistical significance in the PVL group in the intrapartum period. Then another study was conducted to evaluate the relationship between fetal heart rate (FHR) decelerations and cystic PVL prospectively. Since January 1993 through December 1994 we studied 209 low birth weight infants (31.1 +/- 3.2 weeks, 1,424 +/- 419 g) who had been subjected to intrapartum FHR monitoring and postnatal sonographic intracranial examinations sequentially every 7 days until discharge. Cystic PVL was detected in 6 of 209 cases (2.9%) and occurred only in infants who had revealed severe variable deceleration or prolonged deceleration (6/37, 16%) in intrapartum FHR monitoring. We conclude that in low birth weight infants intrapartum severe variable deceleration or prolonged deceleration might play a causal role in cystic PVL.

The effects of pulsatile and nonpulsatile systemic perfusion on renal sympathetic nerve activity in anesthetized dogs

It is still controversial whether to pulse or not to pulse for the establishment of ideal extracorporeal circulation. We directly measured the renal sympathetic nerve activity in mongrel dogs (n = 10, weighing from 13 to 21 kg) to determine the effects of pulsatile and nonpulsatile systemic perfusion on the control of the sympathetic nerve activity during left ventricular assistance. Pulsatile perfusion was generated with an air-driven, diaphragm-type blood pump, and nonpulsatile perfusion was generated with a centrifugal pump. Renal sympathetic nerve activity and the blood flow of the descending aorta were then recorded during pulsatile and nonpulsatile systemic perfusion. Other variables, such as mean arterial pressure, central venous pressure, left atrial pressure, and blood gas levels, were kept constant. At the same mean arterial pressure, renal sympathetic nerve activity during pulsatile perfusion decreased significantly to 80% of renal sympathetic nerve activity during nonpulsatile perfusion (26.8 +/- 2.4 vs 33.4 +/- 2.9 spikes/sec, p < 0.01). Total systemic vascular resistance during pulsatile perfusion decreased significantly to 85% of that during nonpulsatile perfusion (5700 +/- 580 vs 6667 +/- 709 dynes.sec.cm-5, p < 0.05). These results suggest that pulsatile systemic perfusion, compared with nonpulsatile systemic perfusion, reduces sympathetic nerve activity and peripheral vascular resistance and thus may improve both microcirculation and organ function.

[Treatment and prognosis of renal cell carcinoma extending into the inferior vena cava]

Out of 173 patients with renal cell carcinoma diagnosed at our department between January 1984 and December 1994, 9 (5.2%) had an inferior vena caval tumor thrombus. They consisted of 6 men and 3 women between 43 and 74 years old with a mean age of 59.8 years. The tumors were on the right and left sides in 5 and 4 patients, respectively. According to the Novick's classification, 2, 1, 4 and 2 patients had level 1 (perirenal), level 2 (infrahepatic), level 3 (intrahepatic) and level 4 (suprahepatic) tumors, respectively. Five patients without distant metastases underwent nephrectomy and removal of the vena caval tumor thrombus. Although renal tumors and vena caval tumor thrombi were completely resected in all of the 5, 4 died of disease within 3 years. Only 1 patient without tumor invasion into the inferior vena caval wall survived over 5 years without disease. Since surgical treatment is the sole radical method for renal cell carcinoma, surgery is recommended for the patients even with a vena caval tumor thrombus unless there are metastases.