QT dispersion in dipper- and nondipper-type hypertension

The aim of this study was to identify the relationship of QT dispersion on 12-lead electrocardiograms and left ventricular mass index on echocardiograms associated with the circadian rhythm of blood pressure (BP). Heart rate and BP were monitored every 30 min for 48 h in 62 patients with essential hypertension using an ambulatory BP monitoring device. The patients were divided into four groups according to gender and circadian BP pattern (nocturnal BP dipper or nondipper). The patients were classified as dippers if their daytime BP decreased by at least 10% during the night and all the other subjects were classified as nondippers. Age, body mass index, and 48-h mean BP were similar among the four groups. During the night-rest period, the systolic and diastolic BP were significantly decreased in dipper-type hypertensives. The maximum QTc interval and QTc dispersion were longer in nondippers than in dippers. Left ventricular mass index (LVMI) had a tendency to increase in nondippers. The nocturnal reduction of BP significantly correlated with QTc dispersion and LVMI. The QTc dispersion significantly correlated with LVMI and interventricular septum thickness.

Ischemic and reperfusion injury of cyanotic myocardium in chronic hypoxic rat model: changes in cyanotic myocardial antioxidant system

OBJECTIVE

The objective was to evaluate the effect of left ventricular function on cyanotic myocardium after ischemia-reperfusion and to determine the effect of cyanosis on the myocardial antioxidant system.

METHODS

Cyanotic hearts (cyanotic group) were obtained from rats housed in a hypoxic chamber (10% oxygen) for 2 weeks and control hearts (control group) from rats maintained in ambient air. Isolated, crystalloid perfused working hearts were subjected to 15 minutes of global normothermic ischemia and 20 minutes of reperfusion, and functional recovery was evaluated in the two groups. Myocardial superoxide dismutase, glutathione peroxidase, glutathione reductase activity, and reduced glutathione content were measured separately in the cytoplasm and mitochondria at the end of the preischemic, ischemic, and reperfusion periods.

RESULTS

Mean cardiac output/left ventricular weight was not significantly different between the two groups. Percent recovery of cardiac output was significantly lower in the cyanotic group than in the control group (56.1% +/- 5.7% vs 73.0% +/- 3.1%, p = 0.001). Mitochondrial superoxide dismutase, mitochondrial and cytosolic glutathione reductase activity, and cytosolic reduced glutathione were significantly lower in the cyanotic group than in the control group at end-ischemia (superoxide dismutase, 3.7 +/- 1.3 vs 5.9 +/- 1.5 units/mg protein, p = 0.012; mitochondrial glutathione reductase, 43.7 +/- 14.0 vs 71.0 +/- 30.3 munits/mg protein, p = 0.039; cytosolic glutathione reductase, 13.7 +/- 2.0 vs 23.2 +/- 4.2 munits/mg protein, p < 0.001; and reduced glutathione, 0.69 +/- 0.10 vs 0.91 +/- 0.24 microgram/mg protein, p = 0.037).

CONCLUSIONS

Cyanosis impairs postischemic functional recovery and depresses myocardial antioxidant reserve during ischemia. Reduced antioxidant reserve at end-ischemia may result in impaired postischemic functional recovery of cyanotic myocardium.

Factors affecting hypertrophic scar development in median sternotomy incisions for congenital cardiac surgery

BACKGROUND

Even after successful operations on children, unattractive postoperative scars are often distressing to patients and their parents. There are no reports about the factors affecting keloid or hypertrophic scar (HS) development after congenital cardiac surgery.

STUDY DESIGN

Postoperative scars were studied in 75 patients 3 months after congenital cardiac surgery by median skin incision. The mean age of the 51 males and 24 females was 2.7 +/- 2.3 years (range, 2 days-12 years). The scars were evaluated according to degree of redness, expressed as redness score, and skin blood flow, as measured by laser Doppler imaging. Skin blood flow ratio was calculated as blood flow at the scar divided by blood flow below the navel. After surgery, 40 patients received 5 mg/kg/day of tranilast, which inhibits the collagen synthesis of keloid fibroblasts.

RESULTS

None of the 75 patients had keloid formation and 21 (28%) developed HS after operation. Mean age of patients with HS (HS (+) group) was 4.4 +/- 3.3 years and that of patients with no HS development (HS (-) group) was 1.5 +/- 1.9 years (p < 0.01). There were no significant differences between these two groups in gender or in pre- or postoperative cyanosis. Hypertrophic scar (+) patients exhibited significantly higher skin blood flow ratios than HS (-) patients (2.7 +/- 1.3 versus 1.4 +/- 0.6; p < 0.001). Hypertrophic scar was seen in 11 of 40 tranilast administered patients (28%) and in 10 of 34 patients not receiving tranilast (29%) (NS). Hypertrophic scar was less apparent in the patients who received tranilast versus those who did not; redness scores were 29.5 +/- 16.5 and 51.6 +/- 14.9, respectively (p < 0.01).

CONCLUSIONS

These data suggest that age and skin blood flow ratio were the factors affecting HS development. Postoperative use of tranilast did not affect the frequency of HS development but did reduce its redness.

[Transverse submammary skin incision for congenital cardiac surgery]

Submammary skin incision has been accepted as cosmetic approach for open heart surgery. During November 1990 to February 1995, 39 ASD patients under 15 years old were operated with either median or submammary skin incision in Okayama University Medical School. For these patients, retrospective study was carried out to determine whether submammary skin incision made surgical procedure complex and whether patients were satisfied with the scar by submammary skin incision. There were 14 submammary skin incision (Group S) and 25 median skin incision (Group M). There was no significant difference in patients profile between the two groups except for sex. Operative time, cardiopulmonary bypass time and aortic cross clamp time had no significant difference between the two groups. Postoperative ICU stay and hospital stay also did not differed between the two groups. Questionnaires for evaluation of the subjective operation scar was sent with 32 answers (82%). There was no significant difference on questionnaire findings. However for the patients without hypertrophic scar, more patients in Group S were significantly satisfied with their scars. Submammary skin incision was safe and easy. It could be alternative of median skin incision. If hypertrophic scar formation could be prevented, more patients would be satisfied with submammary skin incision than median skin incision.

BIT, an immune antigen receptor-like molecule in the brain

We previously found a brain-specific glycoprotein in the rat brain. It postnatally increases and is rich in the mature brain. We cloned cDNA of this protein. It is composed of a signal peptide, a V-type immunoglobulin domain, two C1-type immunoglobulin domains, a transmembrane segment and a cytoplasmic region containing two tyrosine-based activation motifs (TAM) that are variants of the antigen receptor signaling motifs. The overall structure is similar to those of immune antigen receptors. This molecule, BIT (brain immunoglobulin-like molecule with TAMs), is a major endogenous substrates of brain tyrosine kinases in vitro. Cerebral cortical neurons could extend their neurites on BIT-coated substrate and anti-BIT monoclonal antibody specifically inhibited the effect. These findings and our recent study concerning BIT signal transduction mechanism suggest that BIT, an immune antigen receptor-like molecule of the brain, functions as a membrane signaling molecule that may participate in cell-cell interaction.

[A successful retraining of the left ventricle with a left ventricular assist device (bio-medicus) after the arterial switch operation]

We experienced the case of a patient with d-TGA, small VSD who underwent arterial switch operation (ASO) at the age of 8 weeks. In pre-operative UCG, the LV posterior wall thickness was only 3.0 mm. LV systolic pressure had dropped to 29 mmHg at the time of operation. After arterial switch and VSD closure, myocardial contractility and coronary perfusion were good without any ST-T changes, however, the patient could not be weaned from cardiopulmonary bypass. Left ventricular assist device (LVAD) was then applied and LV training was performed with appropriate pre and after-load. On the 4th operative day, the patient was successfully weaned from LVAD. Training of the left ventricle with LVAD will be a useful life-saving method in the case of left ventricular failure after arterial switch operation.

[Successful open commissurotomy and resection of dysplastic myxomatous tissue on the leaflet edges in a neonate and an early infant with critical aortic stenosis]

A neonate and an early infant with critical aortic stenosis successfully underwent open commissurotomy and resection of dysplastic myxomatous tissue on the leaflet edges using cardiopulmonary bypass. Case 1: A 31-day-old boy admitted to our unit with shock. Echocardiography demonstrated critical aortic stenosis and severe left ventricular dysfunction (EF = 15%). Case 2: A 12-day-old boy suddenly deteriorated and required resuscitation with ventilation and inotropic support. Emergency operation was required in both cases using cardiopulmonary bypass with systemic hypothermia (30 degrees C). In both cases, the aortic valve was bicuspid and dysplastic with gelatinous myxomatous tissue on the leaflet edges. Commissurotomy and resection of myxomatous tissue were performed. Their postoperation courses were uneventful and they have been free from medication at present. These results suggest that aortic commissurotomy and resection of myxomatous tissue under direct vision may be preferable for critical aortic stenosis with dysplastic aortic valve.

Effect of ethanol on gastric mucus glycoprotein synthesis, translocation, transport, glycosylation, and secretion

The effect of ethanol on mucus glycoprotein synthesis, intracellular modification, transport, glycosylation, and secretion was studied in rat gastric mucous cells. Preincubation of the in vitro translation mixture containing gastric mucous cells mRNA for 60 min with 0 to 120 mM ethanol caused a decrease in the synthesis of mucus glycoprotein apopeptide by up to 40%. The reduction in translation was time- and ethanol concentration-dependent. After 60 min, translation in the presence of 30, 60, and 120 mM ethanol decreased to 83.3 +/- 2.3%, 75.5 +/- 0.4%, and 63.6 +/- 2.6%, respectively. The experiments conducted with endoplasmic reticulum microsomes, preincubated with ethanol, and used in the studies of cotranslational translocation of the apomucin showed a 20% decrease in the transfer of mucus glycoprotein apopeptide to the lumen of endoplasmic reticulum microsomes. In the presence of ethanol, processing of mucus glycoprotein apopeptide in Golgi was also inhibited. During the initial 30 min of incubation with 0 to 120 mM ethanol, glycosylation seemed to proceed at the same rate in the samples with and without ethanol. However, during consecutive 30 min of incubation, glycosylation in the presence of 60 mM ethanol decreased by 30 to 35%, and with 120 mM ethanol was completely inhibited. Measurements of the effect of ethanol on the discharge of mucus glycoprotein from the intracellular stores revealed that, on average, the secretory output of the rat gastric mucosa exposed to ethanol liquid diet for 8 weeks decreased by 77% or more, and adherence of the glycoprotein to the gastric epithelium was weakened. Results indicate that ethanol inhibits synthesis, transport, and processing of gastric mucus glycoprotein, and that the processes taking place in different intracellular compartments contribute in the additive fashion and, are reflected in a dramatic decrease in the delivery of mucus glycoprotein to the gastric epithelial surfaces.

New evaluation method for postoperative scar redness

Even after successful operations, ugly postoperative skin scars are often distressing to patients and their parents. To judge the success of surgical methods and postoperative treatment, postoperative scars should be evaluated using a quantitative system. Height and width are easily measured, but scar redness is not. We have developed a simple and effective method for evaluating scar redness. According to the color definitions employed in computer graphics, each color can be expressed as RGB (red, green or blue) coordinates (r, g, b): 0 < or = r, g, b < or = 10. The degree of scar redness is defined by the following formula: redness score (RS) = (r1 - r0)2 + (g1 - g0)2 + (b1 - b0)2. Here, (r1, g1, b1) = coordinates of the scar color and (r0, g0, b0) = coordinates of the surrounding skin color. RS was evaluated in 59 children (35 males, 24 females; ages 1 month to 12 years old) who had scar redness after congenital cardiac surgery. For each patient, scar color and surrounding skin color was identified on the color sample table. Scar redness was also evaluated by the conventional grading method: 1 = mild, 2 = moderate and 3 = severe. The RS of the colored scars ranged from 4 to 100 (38 +/- 27). By the conventional grading method, 44 scars were grade 1, 15 grade 2 and none grade 3. RS was significantly higher among grade 2 than grade 1 patients, 52 +/- 25 and 33 +/- 27, respectively (P < 0.05). Given its subjectivity, the conventional grading method yields variable data surrounding skin color, moreover, is not considered. Our new evaluation method using RS effectively and accurately defines scar and skin colors, and allows quantitative studies of these factors.

[Coronary artery bypass grafting using arterial grafts in a patient with rheumatoid arthritis requiring steroid therapy]

We report a 58-year-old man with rheumatoid arthritis (RA) who underwent successful coronary artery bypass grafting (CABG) for stable angina after myocardial infarction. He had been receiving prednisolone for 9 years. Selective coronary angiography revealed 99% stenosis in the left anterior descending branch (LAD; seg. 6). Before going on cardiopulmonary bypass, the inferior epigastric artery (IEA) was anastomosed to the left internal thoracic artery (LITA) in end-to-side fashion. The LITA was anastomosed to LAD (seg. 7) and the IEA was anastomosed to the first diagonal branch (seg. 9). The postoperative course was uneventful and postoperative angiography showed both grafts were well patent. He is now doing well with no angina attack. The stumps of the LITA and IEA were examined pathologically with the atherosclerotic changes of both grafts relatively mild. We consider the arterial grafts are useful for CABG even in the patient with RA requiring steroid therapy.

Endosonography-guided endoscopic resection of duodenal carcinoid tumor

Endoscopic resection techniques using snare polypectomy with or without submucosal saline injection have also been applied to resect smaller duodenal carcinoid tumors. We report on two patients where endoluminal ultrasound using a small diameter probe was used to visualize the adherence of the carcinoids to the underlying wall layers and the separating effect of subtumoril saline injection. One patient, in whom a clear separation between the tumor and the underlying tissue after saline injection was visualized, underwent successful endoscopic resection. In the other patient no clear separation could be achieved after saline injection and the patient underwent surgical removal of his tumor; both tumors were 1 cm or less in their maximal diameter.

Analysis of giant cell tumor of bone with pulmonary metastases

The authors reviewed 6 cases of giant cell tumor of bone with pulmonary metastases, analyzed the growth rate of the metastases, and performed flow cytometry on paraffin blocks from primary and metastatic lesions. Surgery on the pulmonary metastases was done in 3 cases. Chemotherapy was administered in all 6 cases. If the doubling time of the pulmonary metastases was more than 80 days, the case was considered to be slow growing or in regression. However, if the doubling time was approximately 30 days, the prognosis was poor. The cases were divided into 3 types according to the prognosis. After chemotherapy (cyclophosphamide), the pulmonary metastases decreased in size in 2 cases. In 2 other cases, the metastases were slow growing, and the remaining 2 patients died early. Flow cytometric analysis was performed on primary and metastatic lesions, which showed a diploid pattern in most cases, but a tetraploid pattern in 1 recurrent case. Pulmonary metastatic lesions displayed a diploid pattern in 4 cases from which materials were taken either at surgery or autopsy.

Administration-time-dependent effects of diltiazem on the 24-hour blood pressure profile of essential hypertension patients

The aim of this study was to identify differences in the patterns of efficacy and duration of effect by diltiazem given in different dosage forms and schedules. Blood pressure (BP) and heart rate (HR) were monitored before and after treatment by ambulatory blood pressure monitoring for 48 h every 30 min. Patients were divided for treatment assignment into 4 groups -nocturnal BP dippers and nondippers. In dipper hypertension, diltiazem-retard at 08:00 (n = 7) had the most marked antihypertensive effects during nighttime rest (SBP; 136 +/- 14/118 +/- 9 mmHg, p < 0.01 before vs. after treatment). Diltiazem-retard at 19:00 (n = 6) exerted greatest effect during daytime activity (152 +/- 7/139 +/- 6, p < 0.01) with inhibition of the morning BP rise. Diltiazem (t.i.d., n = 5) had the best effect during daytime activity (151 +/- 16/136 +/- 9, p < 0.05). However, in nondipper hypertensive patients, diltiazem (t.i.d., n = 8) had the most pronounced antihypertensive effects during nightly rest (144 +/- 12/127 +/- 12, p < 0.05). Evening medication with diltiazem retard appears to be more efficacious than the other dosage schedules.

Vascular reconstruction in limb salvage operations for soft tissue tumors of the extremities

Eight patients with vascular threatening soft tissue tumors underwent wide excision of the tumors followed by vascular reconstruction. Superficial femoral vessels were resected in 6 patients and popliteal vessels in 2 patients. Arterial reconstruction was performed with a synthetic graft in 4 and a reversed saphenous vein graft in 4. Venous reconstruction was performed with a synthetic graft in 5 and a saphenous vein graft in 2. Adjuvant multimodality treatment was used in 6 patients. After an average of 30 months, the revascularized vessels were found to be patent in 5 patients with arterial reconstruction and in 1 patient with venous reconstruction. Six patients maintained functional extremities. Two other patients had to have amputations, 1 because of a deep infection that involved the grafts and the other because of an acute occlusion of the reconstructed artery. Edema of the leg, which was treated successfully with an elastic support and elevation of the leg, has been observed in all patients after operation. No local recurrence has been observed with an average followup period of 42.5 months. Pulmonary metastasis developed in 2 patients, and 1 of them underwent a pulmonary metastasectomy. Limb salvage in vascular threatening soft tissue tumors using vascular reconstruction techniques is useful and preferable in some patients.

A 120-MHz ultrasound probe for tissue imaging

Ultrasound transducers with center frequency above 100 MHz are expected to be used for future diagnostic tissue characterization because of their high lateral resolution. We have fabricated a 120-MHz transducer that consists of a ZnO piezoelectric film on a sapphire substrate that has a concave acoustic lens. The lateral resolution was calculated as 13 microns. The insertion loss of the transducer, defined as the difference between the received voltage and the transmitted one, was -45 dB. The 6-dB handwidth of the received signal was approximately 40 MHz. The transducer was mounted in a rod-shaped probe to ensure contact with in vivo tissue, because of the low penetration of ultrasound in the high frequency region. While the probe is rotated and moved along its axis mechanically, the transducer receives backscattered ultrasound from the surrounding tissue on a cylindrical plane that is kept a constant distance from the probe surface. The feasibility of this high-frequency tissue imaging probe has been demonstrated by obtaining preliminary images of an in vitro bovine kidney.

Description of new composite tissue transfer for salvage of a complex hand defect

Leiomyosarcoma of the soft tissue involving bones is an extremely rare tumor. In the past, a hand tumor of this type required amputation. Presently, with improved chemotherapy and reconstruction, the hand and its dexterity sometimes can be saved. In this case, after chemotherapy, the authors opted for wide excision including the skin, tendons, muscles, and bones. The large defect was reconstructed with an iliac crest autograft and a dorsalis pedis free flap including tendons. Functional result was excellent in this patient. The pathologic results also were reviewed by histology, immunohistochemistry for muscle marker, and electron microscopy.

Gastric duplication cyst: evaluation by endoscopic ultrasonography and magnetic resonance imaging

Endoscopic ultrasonography (EUS) and magnetic resonance imaging (MRI) are becoming popular methods for examining tumorous lesions along the upper gastrointestinal tract. Though duplication cysts are uncommon, EUS findings from gastric duplication cysts have accumulated and proven very useful for preoperative diagnosis. There have been few reports, however, concerning MRI findings from these cysts. We report herein the case of a 25-year-old man with a gastric duplication cyst. EUS demonstrated a cystic mass adjacent to the fourth layer of the stomach wall. MRI revealed a cyst containing low signal-intensity fluid and high signal-intensity fluid separated by levels. In addition to the characteristic findings from preoperative examinations, the unique histological findings from the cyst are also described.

[Evaluation of pulmonary perfusion in a patient with agenesis of the left pulmonary artery: usefulness of radionuclide angiography]

We reported a case with agenesis of the left pulmonary artery, in which radionuclide angiography with 99mTc-HSA and time activity curve (TAC) were useful in evaluating pulmonary perfusion in the effected lung. The case involved a 32-year-old male, who underwent nuclear medicine examination including 99mTc-MAA scanning, 81mKr scanning and 99mTc-HSA angiography. 99mTc-MAA and 81mKr scanning showed the perfusion defect and decreased ventilation in the effected lung, respectively. On the other hand, the delayed images of 99mTc-HSA angiography showed the existence of perfusion in the effected lung, although the early images showed the perfusion defect in the same lung. The TAC whose region of interest was placed on the hilus showed that the effected lung was gradually filled with the blood flow through the collateral pathways. In addition, the ratio of area under the TAC on the contralateral lung versus the effected lung was 4.6, while the volume ratio of the contralateral lung versus the effected lung obtained from X-ray CT images was 2.7. Therefore, it was suggested that the perfusion per volume in the effected lung was decreased, compared with that in the contralateral lung. It was concluded that 99mTc-HSA angiography was useful in evaluating the perfusion of the effected lung in a patient with agenesis of the left pulmonary artery.

Successful transplantation of cadaver hearts harvested one hour after hypoxic cardiac arrest

BACKGROUND

A shortage of donor organs in clinical transplantation prompted us to study whether resuscitated "dead" hearts could be used for successful orthotopic heart transplantation.

METHODS

Donor hearts were resuscitated with cardiopulmonary bypass after 3 minutes (the control group; n = 8) or 60 minutes (the experimental group; n = 6) of hypoxic cardiac arrest after induction of brain death.

RESULTS

All the animals of each group were successfully weaned from cardiopulmonary bypass with 5 micrograms/kg/min of dopamine 1 hour after transplantation, and cardiac function with or without dopamine was better preserved in the experimental group than the control group (with maximum slope of pressure-volume relationship with dopamine: 198.0% +/- 36.8% versus 121.2% +/- 47.2%; maximum slope of pressure-volume relationship without dopamine: 130.6% +/- 41.5% versus 70.8% +/- 21.5% [mean +/- standard deviation] as percentage of values after brain death, respectively; p < 0.01 by unpaired t test).

CONCLUSIONS

These results indicate that cadaver hearts 60 minutes after anoxic arrest can be successfully reanimated and orthotopically engrafted with various methods and drugs.