[Noninvasive and quantitative evaluation of pulmonary regurgitation by pulsed Doppler echocardiography--a study in patients with tetralogy of Fallot after corrective surgery]

A noninvasive and quantitative evaluation of pulmonary regurgitation (PR) using pulsed Doppler echocardiography (PDE) was performed in 25 patients with tetralogy of Fallot (TOF) after corrective surgery. Considering a possibility of the presence of the difference in regurgitant flow velocity in pulmonary artery, four sampling points for detecting the pulmonary regurgitant flow were designed as follows: point 0 was positioned at the right ventricular outflow tract; point 1, at the pulmonary annulus; point 2, at mid-portion of the pulmonary trunk; point 3, at bifurcation of the pulmonary artery. The values of maximum Doppler shift determined by analysing the sonograms recorded at point 1, 2 and 3 were examined in comparison with the grades of PR estimated by pulmonary arteriography and the results obtained were as follows. In a retrospective study in 18 patients with PR, the values of maximum Doppler shift were highest at point 1, and followed by point 2 and point 3 in order (p less than 0.005), indicating that the velocity gradient of regurgitant flow existed in the pulmonary artery. The values of maximum Doppler shift were highest in the group of PR grade III estimated by pulmonary arteriography, and followed by the group of PR grade II and grade I in order. At point 2, the group of grade III-PR showed significantly higher Doppler shift than the group of grade I-PR (p less than 0.05). Following above data, a new criteria for estimating the severity of PR by PDE according to the velocity gradient of regurgitant flow in the pulmonary artery was proposed. In a prospective study in a separate group of other 7 patients, the grade of PR estimated by PDE corresponded well with these of pulmonary arteriography, with a significant Spearman rank correlation coefficient (rs = 0.90, p less than 0.01). An experimental study using a dog with surgically induced PR of different grades confirmed the presence of higher Doppler shift in pulmonary artery corresponding to the grade of PR. These results indicated the usefulness of a newly proposed method evaluating PR by PDE applying a concept of Windkessel model for PR regurgitant flow.

Preparation of prolonged-release spherical micro-matrix of ibuprofen with acrylic polymer by the emulsion-solvent diffusion method for improving bioavailability

Prolonged-release spherical micro-matrices of ibuprofen with acrylic polymer (Eudragit RS) were prepared using a novel emulsion-solvent diffusion method. It was found by examining cross sections of the spherical matrix before and after dissolution tests with a scanning electron microscope and a porosimeter that the resultant micro-matrix had a sponge-like internal structure. The spherical matrices were successfully recovered with a relatively high concentration of the drug in ethanol (0.4-0.6 g/ml) and over a wide range of temperatures (5-35 degrees C). The size of the spherical matrix could be easily controlled by varying the agitation speed of the system and the concentration of emulsifier added to the aqueous medium. The drug release rate from the spherical matrix decreased with increasing concentration of polymer formulated due to the reduced diffusion path and increased tortuosity in the matrix. Spherical matrices with ibuprofen:Eudragit RS = 3:1 improved the bioavailability of the drug and prolonged the drug action in beagle dogs.

Right ventricular myocardial function after atrial switch operation for transposition of the great arteries

Postoperative right ventricular (RV) myocardial function was evaluated in 6 patients who underwent atrial switching for simple transposition of the great arteries (TGA). The average age at study was 5.5 years. RV function was evaluated at rest and during administration of methoxamine by cardiac catheterization and RV angiography. The data were compared with left ventricular function in a control group, which consisted of 6 patients, 3 with functional murmur and 3 with pulmonary valvar stenosis. During stress, the TGA group showed a significant increase in end-diastolic pressure, minute work index and end-diastolic and end-systolic volume indexes, along with a significant decrease in ejection fraction. The control group also showed an increase in these variables except for ejection fraction during stress, which did not change. The slope of the work-function curve for the TGA group was lower than that for the control group (p = 0.02). The TGA group had a lower slope of the peak systolic pressure-volume relation than the control group (p = 0.005). There was no significant correlation between the slope of the peak systolic pressure-volume relation and age at repair or study. This study shows that RV pump dysfunction observed in postoperative TGA patients may be caused by depressed myocardial function.

Comparison of preoperative left ventricular function with postoperative left ventricular response to exercise in patients with chronic aortic regurgitation and aortic stenosis

The relation between preoperative left ventricular (LV) systolic function at rest and postoperative LV response to exercise was assessed in 13 patients with aortic regurgitation (AR) and nine patients with aortic stenosis (AS). Preoperative end-systolic volume index (ESVI) and ejection fraction (EF) determined by LV angiography were compared with postoperative exercise-induced changes of LV fractional shortening (delta %FS) and mean velocity of fiber shortening (delta mVcf) assessed by echocardiography. Preoperative EF and ESVI in 13 patients with AR correlated well with postoperative delta %FS and delta mVcf. Similarly, preoperative EF and ESVI in nine patients with AS correlated well with postoperative delta %FS and delta mVcf. Our study demonstrated that preoperative LV systolic function in AR and AS patients closely reflected postoperative LV response to exercise. Preoperative smaller ESVI will be warranted to expect a favorably good postoperative LV response to exercise.

Microrecording for the study of thalamic organization, for tumor biopsy and removal

Use of microrecording technique in stereotactic selective thalamotomy, and in stereotactic biopsy for deep-seated lesions and in tumor removal was briefly described. For selective thalamotomy, the microrecording gives ample information to delineate thalamic subnuclei. Thus, the ventrointermedius (Vim) nucleus is identified by high-amplitude background activity and large-spike discharge, some of which responds solely to contralateral natural stimuli of kinesthetic modality. A small coagulation including this thalamic Vim point resulted in permanent arrest of the various kinds of tremor. As the normal brain tissue, whether the gray or white matter, is electrically active, the microrecording is useful to delineate the brain tumor from its surroundings. Stereotactic diagnostic biopsy and removal of the brain tumor were facilitated by this adjuvant method.

Preparation of controlled-release microspheres of ibuprofen with acrylic polymers by a novel quasi-emulsion solvent diffusion method

A novel quasi-emulsion solvent diffusion method to prepare the controlled-release microspheres of ibuprofen with acrylic polymers has been developed. An ethanol solution of ibuprofen and acrylic resin was poured into aqueous medium with stirring. The finely dispersed ethanolic droplet-like coacervates formed in aqueous medium were gradually solidified and transformed into microspheres during agitation. The size of microspheres was determined by the concentrations of drug and polymer and the agitation speed of the system. The flowability, the packability, and the compressibility of the resultant microspheres were much improved compared with the raw crystals of the drug. The drug release rate from the microspheres could be controlled by the type and the concentration of polymer formulated. A unique principle of the present method and the resultant microspheres, having a matrix- or sponge-like texture, can provide characteristic advantages compared with a conventional reservoir-type device drug, like a microcapsule.

Prevention of pulmonary edema developing in autoperfusing heart-lung preparation by leukocyte depletion

We investigated the preventive effect of leukocyte depletion on the development of pulmonary edema in a 12 h autoperfusing heart-lung preparation (AHLP). Sixteen mongrel dogs were divided into two groups: control group (group C, n = 9) and leukocyte depleted group (group L, n = 7). In group L, leukocytes were depleted with a leukocyte removal filter prior to the preservation. Extravascular thermal volume (EVTV) was measured by thermal-dye dilution technique as a parameter of pulmonary edema during preservation. The white blood cell (WBC) count was measured before and during preservation. After the procedure, extravascular lung water (EVLW) was measured by a gravimetric technique. In group C, the WBC count significantly decreased soon after the start of preservation, and subsequently remained without significant changes. In group L, the WBC count was maintained at a low level during the entire course of preservation. In group C, EVTV increased significantly with the preservation time. In group L, a significant increase in EVTV was only found at 12 h to a smaller extent than in group C. EVLW was significantly smaller in group L than in group C. In conclusion, the development of pulmonary edema was apparently prevented in the 12 h canine AHLP model by leukocyte depletion, and pulmonary leukocyte sequestration was considered as a cause of pulmonary edema in AHLP.

Prostatic carcinoma with melanosis

Melanosis in which melanin deposition is found in the epithelia and stroma or blue nevus of the prostate gland is an uncommon lesion, and the histogenesis is still unclear. To our knowledge, there have been only two case reports in which prostatic melanosis and prostatic adenocarcinoma were both present. This article reports a third case having this combination and discusses the existence of melanin pigment in the carcinoma cell with melanosis.

Crystalloids in latent prostatic carcinoma

Intraglandular crystalloids have been studied in 108 cases of latent prostatic carcinoma collected at autopsy. The morphological features of these crystalloids are essentially the same as reported by previous authors. The crystalloids were identified in 62.0% of cases over age 50 years. They were present in 76.9% of cases in the seventh decade, the highest prevalence among the decades. The number of crystalloids relative to the number of malignant glands tended to be inversely proportional to the size of the carcinoma. We conclude that crystalloids are related to the early development of prostatic carcinoma.

The mechanism of discordant xenograft rejection

The mechanism of discordant xenograft rejection using the guinea pig-to-rat heart graft model was studied. In this model, we found that (A) Rejection occurred rapidly, in 17.5 +/- 8.3 min (mean +/- SD) (n = 8). (B) The graft survived longer when the recipient rat was pretreated with cobra venom facter (CVF). (C) Complement hemolytic titers in serum showed significant reduction of C3 in rejection without consumption of C4 and C2, suggesting complement activation through the alternative pathway. (D) No natural antibodies were detected in this combination. Complement-dependent cytotoxicity (CDC) titer, and hemagglutination (HA) titer were lower than x1. (E) Histological examination of the rejected heart xenograft revealed a large area of myocytolysis without interstitial cellular infiltration. (F) In vitro experiments showed that rat complement attacked guinea pig erythrocytes (Egp) via the alternative pathway. These findings indicate that rejection in this discordant xenograft model of guinea pig-to-rat was caused by primary activation of complement via the alternative pathway.

Experimental and clinical study of crystalloid cardioplegic solution in neonatal period and early infancy. Effects of calcium and prostacyclin analogue

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

Budd-Chiari syndrome treated by Senning's procedure

Two patients with Budd-Chiari syndrome who underwent a new surgical procedure developed by Senning are reported. A 33-year-old man was diagnosed as having Budd-Chiari syndrome with a membranous obstruction of the inferior vena cava (IVC) and right hepatic vein and short segmental obstruction of the left hepatic vein. Removal of the obstruction by dorsocranial resection of the liver and reconstruction of the veins by hepatoatrial anastomosis was carried out. In a 53-year-old female, the same procedure was carried out for a short segmental obstruction of the IVC and left hepatic vein. In both patients, postoperative examination revealed good patency of the IVC and the hepatic veins and increased portal venous flow as measured by Doppler-echography. This procedure is considered the method of choice for Budd-Chiari syndrome with membranous and/or short segmental obstruction of the IVC and hepatic veins.

Prediction of postoperative respiratory failure in patients undergoing lung resection for lung cancer

To evaluate the correlation between predicted postoperative lung function and postoperative respiratory morbidity, 156 patients with lung cancer who underwent resection were classified into four groups based on the degree of postoperative problems: Group 1--no problems (116 patients); Group 2--retention of sputum or atelectasis requiring bronchofiberscopy two or more times (17 patients); Group 3--tracheostomy or mechanical ventilation for more than 2 days or both (14 patients); and Group 4--postoperative death (9 patients). The mean ages of Groups 2, 3, and 4 were significantly (p less than 0.05) higher than the mean age of Group 1. The predicted postoperative lung function (F) was assessed by the formula F = [1-(b-n)/(42-n)] x f, where f is the preoperative vital capacity or forced expiratory volume in one second, b is the number of subsegments of the resected lung lobe, and n is the number of subsegments obstructed by the tumor, which was assessed by the findings on the chest tomogram, on the bronchogram, at bronchofiberscopy, or a combination of these. The total number of subsegments was assumed to be 42. The predicted postoperative % FEV1 was 65.1 +/- 19.3% in Group 1,55.3 +/- 10.6% in Group 2,37.6 +/- 12.1% in Group 3, and 42.3 +/- 18.4% in Group 4. It was significantly (p less than 0.05) different between all the groups except between Groups 3 and 4. All 10 patients with a predicted postoperative % FEV1 of less than 30% were in Groups 3 and 4. We conclude that special attention to postoperative management is needed for patients whose predicted postoperative %FEV1 is lower than 30%.

Experimental study on diaphragm fatigue during diaphragm pacing

An experimental study was performed to determine the main site of fatigue associated with diaphragm pacing. Using 24 mature mongrel dogs, weighing 7.5 to 12.7 kg, direct phrenic nerve pacing was conducted from the right cervical area at three different respiration rates, 37 (Group 1, n = 6), 25 (Group 2, n = 6) and 12 (Group 3, n = 6) times per minute, under fixed stimulation conditions (pulse duration, 200 microseconds; frequency, 25 Hz; pulse train repetition time, 1.2 sec). Diaphragm fatigue was defined as the reduction in transdiaphragmatic pressure (Pdi) to less than or equal to 60% of the initial value. In each animal, tidal volume (Vt), induced muscle action potential (Edi), conduction time (CT) and electrical current (E) between two electrodes were examined at various periods until fatigue. In addition, after fatigue, aminophylline (10 mg/kg) was injected and each parameter was observed for an additional 45 min. In 10 animals, the polarity of stimulation was changed from anodal to cathodal current after fatigue and changes in Pdi and Edi were examined. The time to fatigue was 70 +/- 20 min for Group 1, 149 +/- 48 min for Group 2, and 371 +/- 97 min for Group 3, showing a significant stimulation rate dependency (P less than 0.05). Vt and Edi showed a significant decrease (P less than 0.05) at fatigue in all of the groups. However, no significant differences of CT and E were seen between pre- and postfatigue values. Pdi and Edi did not change even when polarity was changed after fatigue. Following administration of aminophylline, Pdi showed a significant (P less than 0.05) increase over time in all groups: 19.8 +/- 13.5% at 5 min, 23.0 +/- 13.5% at 15 min, and 16.2 +/- 14.9% at 30 min for Group 1; 23.6 +/- 11.6% at 5 min, 27.3 +/- 15.5% at 15 min, and 19.0 +/- 16.1% at 30 min for Group 2; and 29.9 +/- 21.1% at 5 min, 29.5 +/- 18.6% at 15 min, 22.3 +/- 13.8% at 30 min, and 15.5 +/- 13.4% at 45 min for Group 3. In contrast, administration of aminophylline caused no significant changes in Edi. Based upon the finding that aminophylline was significantly effective at the time of diaphragm fatigue, it is concluded that fatigue of the muscle itself constitutes one of the contributing factors for the fatigue phenomenon associated with diaphragm pacing.

[Minimal requirement for successful late results of valve replacement for aortic regurgitation and aortic stenosis]

This study was consisted of 69 patients undergoing aortic valve replacement for chronic aortic regurgitation (AR) and 29 patients, for aortic stenosis (AS) between 1978 and 1985. There was no operative death. There were 7 late cardiac deaths in AR patients, with preoperative left ventricular end-systolic volume index (LVESVI) greater than 200 ml/m2. None of the 55 patients with an LVESVI less than 200 m/m2 died of cardiac-causes. In AR patients with preoperative LVESVI greater than 200 ml/m2, despite the postoperative reduction of the wall stress, the ejection fraction failed to return to normal, indicating that irreversible myocardial dysfunction was responsible in these patients. There were two cardiac-related deaths in 29 AS patients, who had preoperative LVESVI greater than 100 ml/m2. In postoperative AS patients with LVESVI greater than 100 ml/m2, postoperative contractile function of the left ventricle was poor. In conclusion, minimal preoperative left ventricular function for satisfactory late results and reversal of functional results may be at a lower level was LVESVI 200 ml/m2 in AR patients and 100 ml/m2 in AS patients.

[Assessment of pulmonary blood flow after total cavopulmonary shunt operation and the modified Fontan procedure for univentricular heart]

Pulsed Doppler echocardiography was utilized to elucidate the characteristics of pulmonary arterial (PA) blood flow in five patients without apparent pumping chambers in their right heart circulation after right heart bypass surgery for univentricular heart. Two of these patients underwent total cavopulmonary shunt operation, in which the total systemic venous return drained directly into the PA, bypassing the right atrium and ventricle. Three underwent the modified Fontan procedure with atrial partition, in which the right-sided atrium was reconstructed merely as a pathway from the vena cava to the PA, and atrial contraction was nearly entirely excluded. The flow pattern in the PA was biphasic and forward in all five patients. Pulmonary regurgitation was not observed in any of the patients. The first phase of PA flow had its peak during atrial systole; the second, during ventricular systole. Simultaneous observation of PA flow and pressures demonstrated an inverse relation between PA flow and pressure. Pulmonary venous (PV) blood flow pattern was also biphasic and similar to the PA blood flow pattern with time lags. In conclusion, in cases without pumping right heart chambers, PA flow reflects PV flow resulting from contraction and relaxation of the left atrium and ventricle.