Diagnosis of cardiac thrombosis in patients with atrial fibrillation in the absence of macroscopically visible thrombi

Summary Cardiac thrombosis due to atrial fibrillation (AF) has been recognized as the most common cause of cerebral embolism. However, sometimes no macroscopic thrombus is found at autopsy in the heart of a victim of this type of cerebral embolism. We investigated morphological changes in the left atrial endocardium of 31 patients (including 21 cases with AF) who had died of cerebral embolism. Rough endocardium (RE) seen macroscopically provided evidence for the existence of atrial thrombosis. The RE that appeared in AF cases was due to a granular and wrinkled appearance of the endocardium associated with oedematous and fibrous thickening. Fibrin-thread deposits were also always distinguishable. Mural thrombi and oedema with neutrophil infiltration in the subendocardium could be seen under the microscope. Small areas of endothelial denudation and thrombotic aggregations were commonly observed by scanning electron microscopy (SEM). These SEM lesions were significantly more frequent in cases with AF than in controls (P< 0.001). The diagnostic success rate for atrial thrombosis among cases with AF increased from 33.3% to 81% when thrombi proven by histological investigation of the areas with RE were added. Left atrial RE may be an anatomically relevant finding for the existence of atrial thrombosis with AF, when the thrombosis cannot be detected upon gross observation at autopsy.     

Chloramphenicol toxicity associated with severe cardiac dysfunction

Summary A 9-month-old infant experienced severe chloramphenicol toxicity associated with high serum levels (313 g/ml). Cardiovascular collapse with cardiomyopathic changes and impaired left ventricular function was documented by echocardiography. Serial echocardiographic evaluation showed resolution of the cardiomyopathic findings as the chloramphenicol levels were spontaneously cleared. Clinical course was complicated by the development of liver disease and coagulopathy compatible with disseminated intravascular consumption. Patient's recovery was complete and uneventful, nevertheless, chloramphenicol toxicity in childhood is associated with a significant mortality rate of 40%. The related impaired cardiac function, although reversible, appears to play a major role in the pathogenesis and eventual outcome in this syndrome.     

Cardiac function in congenital hypothyroidism: Impairment and response to L-T4 therapy

Summary Electrocardiograms (heart rate, QRS voltage, QRS axis in the frontal plane, Q-Tc interval), echocardiograms [left ventricular fractional shortening (LVFS); preejection period (PEP); PEP/left ventricular ejection time (PEP/LVET) ratio; end-diastolic left ventricular free wall and interventricular septum thickness; presence of pericardial effusion], and thyrotropin (TSH), thyroxine (T₄), and triiodothyronine (T₃) serum levels were evaluated before and 1 week, 1 and 2 months after the start ofl-thyroxine (L-T₄) therapy in 11 infants with congenital hypothyroidism (CH), aged 16–59 days when first seen.Before the start of therapy, infants with CH had significantly lower QRS complexes and LVFS and significantly higher values for Q-Tc, PEP, and PEP/LVET than normal infants of the same age. The QTc interval, PEP and PEP/LVET ratio of infants with CH were significantly greater before than 1 week after L-T₄ therapy, and LVFS was significantly lower before than 1 month after L-T₄ therapy. Four of the infants with CH had small pericardial effusions, which disappeared within the first week of therapy.QRS axis in the frontal plane, Q-Tc interval, and PEP were negatively correlated with logT₄ and logT₃ serum levels. PEP/LVET ratios were negatively correlated with logT₄ serum values. The QRS voltage values were positively correlated with logT₄ and logT₃ serum values. The frontal-plane QRS axis, Q-Tc interval, and PEP/LVET ratio were positively correlated with logTSH serum levels. The QRS voltages were negatively correlated with TSH serum levels.Our data show that before therapy infants with CH have the same functional, but not morphological, abnormalities as older hypothyroid ones and that one third of them have small pericardial effusions. L-T₄ therapy rapidly reverses these changes.     

Noninvasive monitoring of rotary blood pumps: necessity, possibilities, and limitations

Although rotary blood pumps do not contain an inherent mechanism for adaptation to physiological flow necessities, hitherto only a few efforts have been made to obtain robust monitoring and control methods. This paper discusses the necessity of noninvasive monitoring of such pumps and the crucial points of sensor selection and development. A strategy of monitoring atrial pressure out of the data obtained by the collapse of the atrial wall around the inflow cannula and initial results on animal tests and computer simulation of this method are discussed. This approach might lead to reliable and demand-responsive controllers, if some basic criteria are fulfilled.     

Oxygen uptake and carbon dioxide elimination during epinephrine-induced arrhythmias in humans

Key words  cardiac arrhythmias - oxygen uptake - carbon dioxide elimination     

Programming a predictive rormula for angina and other risk factors in patients with cardiac diseases undergoing noncardiac operations

We programmed a formula which predicts the incidence of either myocardial infarction or cardiac death during the postoperative period. The original formula was proposed by Shah et al, based on their own data and analysis. The program is simple and is written in a language called Quick Basic. The use of this program is also simple. Such a program has improved the use of this analysis substantially. The program has been posted on to a few Computer network services as a free software.(Suwa K, Ogura S: Programming a predictive formula for angina and other risk factors in patients with cardiac diseases undergoing non-cardiac operations. J Anesth 6: 241–242, 1992)     

Dandy-Walker malformation: analysis of 38 cases

Thirty-eight cases of Dandy-Walker malformation (DWM) are presented. A female predominance of 3:1 was found. Thirty-two cases (84%) were diagnosed within the 1st year of life. Of these, 17 cases (44.7%) were diagnosed at birth. Ten (26%) were delivered by cesarean section. Thirteen infants (34%) had a birth weight below 3000 g. Several associated malformations were observed, the most frequent being capillary angioma (6 case); cardiac malformations, ophthalmic anomalies, agenesis of the corpus callosum, malformed limbs, and occipital meningocele were also seen. These observations indicate that DWM represents a disorder of the midline central nervous system indicative of marked genetic and etiologic heterogeneity with the possibility of showing clinical and pathological alterations intra-and extracranially. Macrocephaly was the most frequent physical finding, appearing in 31 cases (82%). Seventeen (44.7%) patients died, 11 before 6 months of age, 3 between 6 and 12 months, and 3 after 1 year. Postmortem studies were performed in 13 patients. Three cases have been lost to follow-up. Mental retardation (IQ below 70) was found in 11 cases (58% of survivors), low intellect (IQ between 70 and 85) in 4, and only 2 patients showed normal intellectual development (IQ more than 85). The high incidence of malformations having several genetic and environmental origins, as well as the high early mortality of patients with DWM, indicate the complexity of this syndrome, which involves the midline developmental field structures. It is not an isolated malformation of the posterior fossa in most cases.     

Tryptophan tolerance and metabolism in endogenous depression

The concentration of free and total tryptophan and kynurenine in plasma from 49 female depressives and 26 female controls was measured following oral loading with l-tryptophan, 100 mg/kg body weight. There was no significant difference between five depressives and six controls in the area under curve for free or total tryptophan or kynurenine in plasma. The peak concentration of kynurenine occured 4 h after loading and it correlated significantly with the area under curve for kynurenine. There was no significant correlation between the l-tryptophan dose (g) and the plasma concentration of kynurenine at 4 h in the 49 depressives or 26 controls. The mean plasma levels of tryptophan and kynurenine at 4 h in the depressives were not significantly different from control levels. There was no clear relationship between the plasma levels of tryptophan or kynurenine at 4 h and the therapeutic response in 13 depressives treated with l-tryptophan for 14 days.It is concluded that the absorption, the plasma clearance, and the degradation to kynurenine of loading doses of l-tryptophan are normal in depressed patients. Results further-more suggest that the plasma levels of tryptophan and kynurenine at 4 h are poor predictors of the response to l-tryptophan treatment in depressives.     

Cardiac sensitization induced by phenobarbitone and prolonged by CS2

The arrhythmogenic effect of 8 g/kg noradrenaline given i.v. was increased in male rats pretreated 1–2 day s earlier with phenobarbitone and starved from the time of the first phenobarbitone injection (80 mg/kg followed by 50 mg/kg 6 h later). Daily exposure to 4.0 mg/l CS₂ (first exposure 24 h after the first phenobarbitone injection) for 4 h prevented the decline in susceptibility on the 3rd and 4th days after phenobarbitone, when the reaction of unexposed rats to noradrenaline returned to normal.     

Primary Mitral Valve Sarcoma in Infancy

Primary cardiac sarcoma is a rare tumor, found especially in children, particularly in the left side of the heart. This report describes a rare case of primary mitral valve sarcoma in a 7-month-old male infant with hemiparesis and heart murmur who underwent mitral valve replacement because of excessive invasion of the mitral valve by the tumor. The patient remains well, free of recurrence and cerebral metastasis, and without adjuvant therapy 18 months after the operation.