Biomedical subjects
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A 55-year-old man with tetralogy of Fallot underwent corrective surgery. Left ventricular filling pressure increased markedly with increased left ventricular volume one month after surgery, then decreased over the next 7 months, presumably due to increased left ventricular compliance.
BACKGROUND: The right-to-left shunt at the atrial level is responsible for arterial hypoxemia in patients with atrial septal defect. OBJECTIVES: This study investigated the mechanism of arterial hypoxemia in patients with atrial septal defect by measuring the P(O2) in both the right and left upper pulmonary veins. SUBJECTS AND METHOD: We prospectively measured the P(O2) in the femoral artery and the right and left upper pulmonary veins during cardiac catheterization in 13 adults (median age, 53 years) and 7 children (median age, 7 years) with secundum atrial septal defect. The adults and children were studied consecutively. Contrast echocardiography was performed to evaluate right-to-left shunt in all adults. RESULTS: Among the children, there were no patients showing arterial hypoxemia, and there was no difference in the P(O2) (+/-SD) between the right and left upper pulmonary veins (right, 100+/-3.8 mm Hg vs left, 100+/-7.8 mm Hg; p = 0.92). However, arterial hypoxemia was present in 11 of the 13 adult patients, although contrast echocardiography showed more than a moderate degree of right-to-left shunt in only four adults. The P(O2) was lower in the left upper pulmonary vein than it was in the right upper pulmonary vein in all adult patients (right, 91.6+/-13.8 mm Hg vs left, 73.0+/-11.5 mm Hg; p < 0.0001). CONCLUSION: The P(O2) was lower in the left upper pulmonary vein than it was in the right upper pulmonary vein in adults with atrial septal defect. Care must be taken in measuring pulmonary blood flow if the P(O2) in the left upper pulmonary vein is low enough to influence oxygen content. The decreased P(O2) in the left upper pulmonary vein may contribute to arterial hypoxemia in addition to right-to-left shunt at the atrial level in adults with atrial septal defect.
Thrombin-antithrombin III complex (TAT) is a marker of thrombin generation, indicating increased coagulability. To investigate whether paroxysmal atrial fibrillation (PAf) is associated with an increased coagulation system, we measured TAT within 24 h after the documentation of PAf in 50 patients with structurally normal hearts. The mean age of the study population was 62 years old. In 32 patients, PAf was documented during routine physical examinations, electrocardiograms or echocardiograms and in the remaining 18 patients, it was reproducibly documented on more than two Holter electrocardiograms. Group I consisted of 38 TAT data sets from 38 patients who did not receive anticoagulant therapy during PAf episodes. At least one week after starting anticoagulant therapy, TAT was measured again in ten patients in whom there was evidence of PAf on the day of measurement. In the remaining 12 patients, PAf occurred while the patients were receiving anticoagulation. Group II consisted of 22 TAT data sets from 22 patients who received anticoagulation during PAf episodes. The average TAT value was 5.8 ng/ml in group I, while it was 2.8 ng/ml in group II (P<0.0001). TAT was greater than 5 ng/ml in 15 of the 38 patients in group I, and in four of the 22 patients in group II. In 20 symptomatic patients, we measured TAT again when the patients maintained sinus rhythm under the same anticoagulant therapy; four patients were receiving and 16 patients were not receiving anticoagulation therapy. TAT decreased from 6.4 to 2.3 ng/ml on average when PAf disappeared and sinus rhythm was maintained (P=0.0009). Increase in the coagulation system occurred transiently during or shortly after PAf episodes in about 40% of PAf patients. As patients with prior anticoagulation had a relatively low TAT value, anticoagulant therapy might be useful in patients with PAf.
We present the case of a 39-year-old woman with aortic regurgitation that may have been induced by primary antiphospholipid syndrome. The patient had suffered recurrent miscarriages, thrombocytopenia, and deep-vein thrombosis for the previous 16 years, and had been diagnosed as having primary antiphospholipid syndrome 9 years previously because of a high titer of anticardiolipin antibody. She had been receiving medication for moderate hypertension for 7 years. The patient was admitted to Tenri Hospital because of heart failure, which was thought to be caused by moderate aortic regurgitation, moderate hypertension, and mild chronic renal failure. Echocardiography revealed thickened aortic and mitral valves. Primary antiphospholipid syndrome might have induced valve regurgitation as a result of valvular thickening.
We describe a 60-year-old patient with adrenal insufficiency and hypothyroidism who experienced syncope as a result of polymorphic ventricular tachycardia associated with long QT intervals. The deep inverted T waves and long QT intervals were normalized about 8 weeks after starting steroid replacement therapy. Although there have been some reports on electrocardiographic abnormality or polymorphic ventricular tachycardia in patients with adrenal insufficiency, the pathogenesis remains unknown. Hormonal disorders should be considered as a cause of polymorphic ventricular tachycardia associated with long QT intervals, even if plasma electrolyte levels are normal, because life-threatening arrhythmia is treatable by supplementation of the hormone that is lacking.
Chest pain in patients with hypertrophic cardiomyopathy seems to be caused by relative myocardial ischemia due to the left ventricular outflow pressure gradient and myocardial hypertrophy. However, in 2 cases of hypertrophic cardiomyopathy chest pain was associated with coronary vasospasm. Thus, chest pain in these cases was decreased not by a beta-blocker but by isosorbide dinitrate and a calcium antagonist. Because beta-blockers are commonly used for hypertrophic obstructive cardiomyopathy and chest pain may be aggravated by beta-blockers in patients with coronary vasospasm, a combination of beta-blocker, isosorbide dinitrate and calcium antagonist was necessary for this hypertrophic cardiomyopathy with variant angina.
To address the problems of pharmacological evaluation in paroxysmal atrial fibrillation (PAf), we interviewed 108 consecutive patients with documented PAf regarding symptoms, frequency and trigger factors of PAf and analyzed the 24-hour ambulatory electrocardiographic monitoring (Holter monitoring) records in relation to symptoms. Twenty-nine patients were totally asymptomatic, while 79 patients were symptomatic of which 49 patients had obvious trigger factors. PAf was documented by Holter monitoring in 22 of 79 symptomatic patients. On analysis of PAf-documented 25 Holter monitoring records, the patients checked event marks as PAf in only 20 of 155 PAf episodes. Six episodes of 26 event marks that patients thought to be PAf proved to be premature atrial or ventricular contractions. Nine patients in whom PAf persisted for more than 24 hours became asymptomatic. Patients suitable for pharmacological evaluation constituted about one-fifth of the PAf patients in our consecutive study. Even with the selection of these patients, pharmacological evaluation based on symptoms is difficult because disappearance of PAf may be associated with persistent atrial fibrillation.
The clinical features and outcomes of patients with cholesterol embolization syndrome after cardiac catheterization were evaluated. Among 4,920 patients undergoing cardiac catheterization during 1991 to 1996, the symptoms, signs, laboratory data, treatment and prognosis of eight (6 males and 2 females, mean age 69 years old) were reviewed who were pathologically or clinically diagnosed as having cholesterol embolization syndrome. All patients had more than two coronary risk factors. Mobile plaque of the aortic arch was detected in all five patients who underwent transesophageal echocardiography. All patients had one or more precipitating factors, including coronary angiography, percutaneous transluminal coronary angioplasty, cardiovascular surgery and cardiopulmonary resuscitation. The first symptom was renal dysfunction in four patients, skin findings of purple toes in two, muscle pain in one and new onset of refractory hypertension in one. The time after the precipitating factor to the onset of symptoms was 32 +/- 9 days on average. Eosinophilia was found in all patients and six patients revealed eosinophilia before the onset of symptoms. Four patients showed skin findings of purple toes which progressed in three of the four patients even after anticoagulant therapy was discontinued. Epidural anesthesia was markedly effective for skin findings of purple toes in two of the three patients. Diagnosis of cholesterol embolization syndrome is difficult because patients show various symptoms and there is an interval between the precipitating factor and the onset of symptoms. However, the conditions of the patients deteriorate rapidly and the prognosis is generally poor without supportive therapy in the early stage. Our study demonstrated that eosinophilia might be an important clue to early detection of cholesterol embolization syndrome. Furthermore, epidural anesthesia is effective for skin findings of purple toes in patients with cholesterol embolization syndrome. In conclusion, cholesterol embolization syndrome should be detected in the early stage based on eosinophilia or clinical symptoms after cardiac catheterization, and supportive therapy started as soon as possible, including discontinuance of anticoagulant therapy, hemodialysis for renal dysfunction and epidural anesthesia for skin findings of purple toes.
An 84-year-old woman was admitted to our hospital because of left heart failure of acute onset. Transthoracic echocardiography showed diffuse hypertrophy of the normal sized hyperkinetic left ventricle and chordae-like fluttering echoes attached to the mitral valve with severe mitral regurgitation signals. Mosaic flow signals were seen at the left ventricular outflow tract, but the velocity could not be measured. Emergent transesophageal echocardiography detected no obvious mitral valve prolapse. Cardiac catheterization showed greater than 100 mmHg pressure gradient between the left ventricle and femoral artery. Pressures in the femoral artery and pulmonary capillary wedge changed reciprocally in the intensive care unit; a bisferient narrow pulse pressure of the femoral artery was associated with increased v wave of the pulmonary capillary wedge pressure, and a wide pulse pressure of the femoral artery with absent v wave of the pulmonary capillary wedge pressure. Pressure monitoring in the intensive care unit, catheterization laboratory and transesophageal echocardiography were useful to understand the pathophysiology of the patient.
We performed percutaneous transluminal recanalization successfully for an occluded modified Potts shunt in a 35-year-old man with pulmonary atresia and ventricular septal defect. Percutaneous transluminal recanalization deserves to be considered for occluded shunts if the duration of obstruction is short.
We encountered a patient with rapid progressing left atrial myxoma in whom two-dimensional echocardiography was serially obtained over eighteen months. The horizontal and longitudinal diameters showed a linear 2.5 fold increase, while the size of the base attached to the left atrial wall remained unchanged. Therefore, the last echocardiogram obtained just before surgery showed the characteristic pendular motion of left atrial myxoma.
We describe a case of dicrotic pulse in a patient who exhibited marked prolapsed aortic cusp without aortic regurgitation. Echo-Doppler in the abdominal aorta showed deep reversal flow confined to early diastole. We conclude that this prolapse was the cause of the steep dicrotic notch and the dicrotic pulse, because of the concomitance of non-leaking aortic valves.
When cumulus-enclosed bovine oocytes were cultured for 24 h in serum-free medium containing 0 to 50 ng/ml EGF, the proportions of oocytes reaching metaphase II were higher (P < 0.05) in the presence of 30 ng/ml EGF (88.1 +/- 1.3%) than under control conditions (65.5 +/- 3.5%) or in the presence of 10 ng/ml (73.9 +/- 4.5%) and 50 ng/ml (73.6 +/- 4.0%) EGF. When oocytes matured under these conditions were inseminated in vitro, the proportions of oocytes penetrated were higher (P < 0.05) in 10 to 50 ng/ml EGF (96.7 +/- 3.3 to 100%) than in its absence (77.9 +/- 8.9%). However, the proportions of penetrated oocytes with male and female pronuclei did not differ among the different groups (96.7 +/- 3.3 to 100%). When oocytes were matured under the same conditions, fertilized in vitro, and cultured until 192 h post insemination in a chemically-defined medium, the proportion of embryos at the >/=2-cell stage was higher (P < 0.05) in the groups treated with 30 ng/ml (96.1 +/- 2.5%) and 50 ng/ml (90.6 +/- 3.5%) EGF than in the controls (71.8 +/- 3.1%) at 48 h post insemination. Although there were no differences in the proportions (37.3 +/- 5.3 to 47.2 +/- 5.8%) of >/=morulae at 144 h post insemination among treatments, the proportion of embryos developing to the blastocyst stage was higher (P < 0.05) in the presence of 10 to 50 ng/ml EGF (16.5 +/- 2.0 to 20.8 +/- 4.9%) than in control medium (3.4 +/- 2.1%). The mean blastocyst cell number at 192 h post insemination did not differ between culture media in the presence (91 to 107 cells) and the absence (116 cells) of EGF (10 to 50 ng/ml) during maturation. Thus, higher proportions of oocytes matured in serum-free medium with EGF than without EGF could develop to the blastocyst stage in a chemically-defined medium after in vitro fertilization. These results indicate that EGF can induce not only nuclear maturation but also cytoplasmic maturation of cumulus-enclosed bovine oocytes in vitro.
The aim of this study was to identify the presence of functional oxytocin (OT) receptors on bovine granulosa cells. Freshly prepared bovine granulosa cells from small (3-5 mm in diameter) or preovulatory (mature) follicles were examined for OT receptors by a radioreceptor assay. Scatchard analysis revealed that both binding capacity and affinity in granulosa cells from small follicles were significantly higher than those in granulosa cells from mature follicles (p < 0.01). With use of a reverse transcriptase polymerase chain reaction analysis, expression of OT receptor mRNA was detected in granulosa cells obtained from both small and mature follicles. When the granulosa cells obtained from small follicles were cultured in Dulbecco's Modified Eagle's Medium and Ham's F-12 medium (1:1 [v:v]) with 10% calf serum up to 72 h, as the period of culture was prolonged, the concentration of OT receptor decreased with increases of progesterone and OT release in the medium. However, the binding affinity was not changed during culture for 72 h. When bovine follicular oocytes with cumulus oophorus were cultured for 24 h in tissue culture Medium-199 with 10% fetal calf serum and OT (0-10 nM), the percentages of oocytes reaching maximum cumulus expansion were significantly increased at 0.5, 1, and 10 nM OT, although nuclear maturation in oocytes surrounded by compact cumulus cells was not affected by the addition of OT. Coexposure with OT antagonist blocked the stimulatory effect of OT on cumulus expansion, confirming the specificity of the effect. Furthermore, anti-OT rabbit serum inhibited the percentages of oocytes with expanded cumulus compared to those supplemented with normal rabbit serum (p <0.05). The overall results indicate the presence of functional OT receptors in bovine granulosa cells and support the hypothesis that OT plays a role (or roles) in regulating the function of granulosa cells as an autocrine factor during follicular growth.
We retrospectively analyzed 20 cases of renal infarction to identify the problems in tentatively diagnosing renal infarction. The subjects consisted of 12 outpatients and 8 inpatients whose diagnosis was confirmed by renal scintigram and/or contrast computed tomography. Renal infarction was tentatively diagnosed in only 4 of the 12 outpatients. Causes of hospitalization were cerebral emboli in 5 cases, peripheral emboli in the extremities in 2 cases and one case involved percutaneous transmitral commissurotomy. On initial urinalysis, 11 cases (55%) showed less than 2+ hematuria using dipsticks to test for occult blood. The mean lactic dehydrogenase value was as high as 2,096 IU while the mean aspartate aminotransferase and mean alanine aminotransferase were 83.1 IU and 78.6 IU. Abdominal ultrasonography revealed abnormalities in only one of 18 cases. In conclusion, since only a moderate degree of hematuria was seen in about half the cases and it was difficult to detect renal abnormalities by ultrasonography, a tentative diagnosis of renal infarction may be difficult in some cases.
OBJECTIVES: The aim of this investigation was to test whether the administration of atrial natriuretic peptide (ANP) has cardioprotective effects against ischaemic and reperfusion injury. METHODS: Thoracotomized dogs underwent a 30 min left circumflex coronary artery occlusion and 60 min of reperfusion (control group; n = 16). The ANP group (n = 9) received a 20 micrograms bolus injection of synthetic alpha human ANP (SUN 4936) followed by infusion at a dose of 0.1 microgram/kg/min from the beginning of coronary occlusion to the end of the procedure. RESULTS: Administration of exogenous ANP increased plasma ANP immediately and maintained levels at 3000 pg/ml, resulting in an 8-fold increase in plasma cyclic guanosine monophosphate (cGMP) levels. Plasma ANP and plasma cGMP levels did not change at all in controls. There were no significant differences in haemodynamic parameters during ischaemia and reperfusion between the groups. In the ANP group, the prevalence and frequency of ventricular extrasystoles within 10 min after reperfusion decreased markedly [ANP 22% vs. control 100%, P < 0.01, and ANP 1 (1) vs. control 92 (50), P < 0.05, respectively]. No dog in the ANP group had ventricular fibrillation (VF), but the incidence of VF was not statistically significant between the groups [ANP 0% vs. control 25%]. ATP content in the inner layers of the ischaemic myocardium in the ANP group was higher than in controls (P < 0.05) [1.92 (0.28) vs. 1.18 (0.13) mumol/g wet weight]. There was no significant difference in the content of myocardial tissue angiotensin II between the groups. CONCLUSIONS: These data show that the infusion of ANP has cardioprotective effects on myocardial ischaemia and reperfusion in this model. These beneficial effects are probably due to direct effects through cGMP rather than haemodynamic changes.
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We present a 74-year-old female in whom a systolic murmur became trans-systolic during the Valsalva maneuver. The patient had had stable effort angina for 20 years and coronary angiography revealed complete obstruction of the left anterior descending artery in addition to other atherosclerotic lesions. Left ventriculography showed a small apical aneurysm with a narrow orifice. Aorto-coronary bypass surgery and aneurysmectomy were performed; true aneurysm was confirmed pathologically. We conclude that apical aneurysm with a narrow orifice can produce trans-systolic murmur.