Structural basis for mitral valve dysfunction associated with ostium secundum atrial septal defects

Mitral valve (MV) specimens obtained at operation from 50 patients with ostium secundum atrial septal defect and associated MV dysfunction were studied macro- and microscopically to evaluate the structural lesions. The functional abnormalities in these patients were isolated mitral stenosis, isolated mitral regurgitation, mitral valve prolapse or mitral stenosis with regurgitation. Post-inflammatory lesions were commonly found in those with mitral stenosis who had a past history of rheumatic fever. Patients with mitral valve prolapse had either post-inflammatory lesions or lesions attributable to haemodynamic stress but different from the extensive lesions seen in floppy MV syndrome.

Discordant atrioventricular connection and concordant ventriculoarterial connection in situs inversus: isolated ventricular noninversion

A case of discordant atrioventricular (AV) connection and concordant ventriculoarterial (VA) connection (with aortomitral fibrous continuity and tricuspid pulmonary discontinuity) in situs inversus (I, D, I) is reported because of its rarity. This segmental combination with abnormally related great arteries in the absence of anomalies of venous connections and/or splenic anomalies is extremely rare.

Clinical course of endomyocardial fibrosis

The survival pattern, morbidity, and clinical course of 145 patients with endomyocardial fibrosis who were followed up between November 1975 and June 1987 were studied. The diagnosis was confirmed in all cases by cardiac angiography, or echocardiography, or necropsy. Percentage survival at the end of one and 9.5 years was 76.11 and 26.35 respectively. History, physical examination, electrocardiography, and cardiac catheterisation were studied at the first presentation. The determinants of early mortality were studied by univariate Kaplan-Meier estimates compared by the log rank test and Cox proportional hazards multiple regression analysis. Significant univariate predictors of early mortality were QRS axis above +90 degrees, intraventricular conduction delay (QRS duration greater than 0.12 s), duration of symptoms before presentation, New York Heart Association functional classes III and IV, presence of embolic episodes, right atrial mean pressures greater than 20 mm Hg, right ventricular end diastolic pressure greater than 20 mm Hg, and aortic oxygen saturation less than 85%. The significant multivariate predictors of mortality were cyanosis, New York Heart Association functional class at first presentation, and right atrial mean pressure greater than 20 mm Hg. The bleak prognosis of endomyocardial fibrosis did not substantially improve despite advances in the medical management of congestive cardiac failure during the period of the study.

A simplified method for culture of human fetal heart tissue

Human fetal heart tissue obtained consequent to suction termination of pregnancy between 6 and 12 weeks of gestation were cultured as explants and maintained in a viable state, with spontaneous contractions up to 75 days. Ultrastructural morphology of the explant revealed that the cells remained healthy up to 21 days in culture. The model can therefore be used for experimental studies during the first 3 weeks in culture.

Interactions of thorium and cerium with adenine nucleotides

The present study demonstrates an effect of the actinide, Thorium (Th), and the lanthanide, Cerium (Ce), on the non-enzymatic hydrolysis of adenine and guanine nucleotides. Thorium was found to be a more effective catalyst of the reaction than Cerium. Further, both the elements promoted the binding of Creatine kinase (CK) to Cibacron blue F3 GA, the substrate analogue of the enzyme, even in the absence of Mg2+, the physiological cofactor. These observations imply that toxic heavy metals can mimic the functional effects of the essential elements despite differences in their physicochemical properties.

A geochemical basis for endomyocardial fibrosis

Analysis of hearts of patients dying from endomyocardial fibrosis showed a significantly greater concentration of cerium, a lanthanide present in leafy vegetables and root tubers, than in control hearts. This may be important in the pathogenesis of the disease and provides a geographical basis for the prevalence of the disease in the tropics.

Synthetic hydrogel microspheres as substrata for cell adhesion and growth

Cross-linked poly(methyl methacrylate) (PMMA) microspheres were subjected to alkaline hydrolysis to obtain hydrophilic microspheres having carboxyl residues distributed throughout the matrix. These microspheres were found to support the growth of human skin fibroblasts and human heart and lung cells. Further, fibroblasts grown on them were found to be comparable with those grown on the commercial tissue culture plate with respect to [14C]amino acid uptake and incorporation into proteins. The hydrolyzed PMMA microspheres may find application as a microcarrier for cell culture.

Non-myxomatous mitral valve prolapse: a clinical and pathological study

Mitral valve specimens from 9 patients with severe mitral regurgitation due to mitral valve prolapse were examined. All belonged to the age group 10-30 years and had rapid progression of their illness, requiring early surgery. The histopathological examination of valve tissue revealed varying degrees of fibrosis, increased vascularity and absence of myxomatous degeneration. These patients may represent a distinct group of mitral valve prolapse, whose clinical course is different from those with typical myxomatous degeneration of the mitral valve.

Unusual manifestation of valvular vegetations

Mitral obstruction due to a large vegetation of bacterial endocarditis occurred in a 30 year old man. 2-D echocardiogram revealed an echodense mass obstructing the mitral valve. The patient was successfully treated by mitral valve replacement.

Surgical treatment of endomyocardial fibrosis

Forty-six patients with endomyocardial fibrosis underwent endocardiectomy and replacement of tricuspid, mitral, or both atrioventricular valves between April, 1981, and October, 1984, at the Sree Chitra Tirunal Institute, Kerala State, India, which has a high incidence of the disease. Six patients were in New York Heart Association Functional Class III and 40 patients in Class IV. The operative mortality within 30 days of the procedure and late mortality during the first two years postoperation were 21.7% and 13%, respectively. Age under 15 years was a significant correlate of operative mortality (p = .05). Non-fatal thromboembolic episodes occurred in 6 patients during the two years of postoperative observation. The life table estimate of survival inclusive of operative mortality at two years was 67%. Despite high operative mortality, endocardiectomy with atrioventricular valve replacement is advisable for functionally disabled patients with endomyocardial fibrosis whose prognosis otherwise is dismal.

A geochemical basis for endomyocardial fibrosis

In a search for geochemical factors that could play a role in the pathogenesis of tropical endomyocardial fibrosis, endomyocardial tissue samples obtained from patients at necropsy or operation were analysed for major elements present in laterite and monazite, which are important soil constituents of Kerala State of India. Atomic absorption spectrophotometry was used for detecting iron, silicon, aluminium, zinc, magnesium, calcium, sodium, potassium, and manganese and neutron activation analysis for thorium. Compared with control samples from victims of fatal accidents, an excess of thorium, sodium, and calcium and a deficiency of magnesium were present in samples from patients. It has been shown earlier that the staple diets of people in Kerala have high concentrations of thorium, and these data show that thorium can become concentrated in cardiac tissues. It is speculated that thorium excess in conjunction with magnesium deficiency may play a role in the causation of tropical endomyocardial fibrosis.

Subvalvar aneurysms of the left ventricle

Five cases of subvalvar aneurysm of the left ventricle are reported. The location of the aneurysm was sub-mitral in three and sub-aortic in two. The clinical, echocardiographic, angiocardiographic and pathological features are described.

Intramyocardial coronary arterial changes in rheumatic mitral valve disease. Relation to left ventricular function

A retrospective analysis of intramyocardial coronary arterial changes was done in excised papillary muscles obtained at surgery in 46 cases with rheumatic mitral valve disease (RMVD). The findings were correlated with left ventricular function. Vessel wall thickening with obliteration of the lumen was found in 15 patients (32.6%) while adventitial and perivascular fibrosis was found in 12 cases (26%). Patients with microarteriopathy had significantly higher left ventricular and diastolic pressure (p less than 0.05), lower ejection fraction (p less than 0.001), and lower cardiac index (p less than 0.01), as compared to patients with no microarteriopathy. The incidence of left ventricular dysfunction and surgical mortality was higher in patients with microarteriopathy (80 and 47%, respectively) than in those with normal microvasculature (26 and 13%, respectively). As a test for predicting left ventricular dysfunction and surgical mortality a positive biopsy was moderately sensitive (sensitivity 60 and 64%, respectively) and highly specific (specificity 88 and 77%, respectively). Successful outcome after mitral valve replacement was correctly predicted by a negative biopsy result in 87% cases. We conclude that in RMVD, microarteriopathy is associated with left ventricular dysfunction and poor postoperative prognosis.

Early angiographic features of right ventricular endomyocardial fibrosis

Right ventricular (RV) angiograms were done in 45 patients with left ventricular (LV) endomyocardial fibrosis (EMF). 34 patients had angiographic features compatible with the diagnosis of RV and LV EMF. 11 patients showed the angiographic features of EMF on the left side, but did not show the classical angiographic features on the right side. The RV angiograms of these 11 patients showed a disturbance of the normal parenchymal pattern along the septal margin, irregular small filling defects near the apex and the septal region and minimal tricuspid regurgitation. Biopsies from the RV taken from 2 of these patients during operation for mitral valve replacement had histological features compatible with the diagnosis of EMF on the right side also. This study demonstrates that the early angiographic features of RV EMF differ from those of well-established cases already described in the literature, and that it is possible to spot RV EMF well before the conventional features appear in RV angiograms.