Eshagh Eshaghpour

Heart failure secondary to hypomagnesemia in anorexia nervosa

We would like to report a case of heart failure due to hypomagnesemia in a patient with anorexia nervosa. Cardiac problems account for much of the 1520% mortality associated with anorexia nervosa [1, 2, 4]. Electrolyte problems are common, but isolated hypomagnesemia was never documented as responsible for ventricular failure. We encountered a 15-year-old girl, with anorexia nervosa since age 13, who presented in heart failure, with dyspnea and orthopnea, having increased her weight from 27 to 37 kg (for a height of 155 cm) in 10 days. Her heart rate was 150/rain and blood pressure 150/100 mmHg. She had a gallop, a murmur of mitral regurgitation, hepatomegaly, and lower extremity edema. The arterial blood gas, on 100% oxygen by rebreather mask, showed pH 7.52, pco2 24 mmHg, po2 48 mmHg. The chest x-ray showed cardiomegaly, central interstitial pulmonary edema, and bilateral pleural effusions (Fig. 1). Echocardiography showed a mildly dilated, poorly contractile, left ventricle. Ejection fraction was 10%. There was moderate mitral regurgitation. The left ventricular mass of 64 g was diminished, and the end-systolic wall stress index of 274 g/cm 2 was elevated. Extensive blood work revealed hypomagnesemia (0.8 mEq/L, normal 1.5-2) as the only predominant biochemical abnormality. Potassium was 3.6 mEq/L. Total calcium was mildly decreased (7.7 mg/dl, normal 8.5-10.7), but serum total proteins were also low (5.4 g/dl, normal 6-8.2), sug-

Signficance of a Q wave in lead I in the newborn

We present 11 healthy newborns whose electrocardiograms had a pure Q wave in lead I and who did not have a myocardial infarction clinically. We propose that in the healthy newborn, a pure Q wave in lead I may be due to increased right ventricular mass, not myocardial infarction.

ECHOCARDIOGRAPHY IN CYSTIC FIBROSIS

Because of the desirability of developing better non-invasive techniques in the detection of early right ventricular changes in children with cystic fibrosis (CF), echocardiography, using continuous strip recording, was performed in 15 patients and compared to other parameters of assessment of cor pulmonale. Right ventricular anterior wall thickness per meter square (RVAW/m2) and right ventricular internal diameter in diastole per meter square (RVIDd/m2) were compared to clinical score of severity of disease, thoracic index, pulmonary involvement by x-ray, pulmonary function, electro- and vector-cardiography.Using RVAW/m2, positive correlation was obtained with clinical score, chest x-ray, FVC and FEV1, while RVIDd/m2 was significantly related to chest x-ray only. The internal relation of RVIDd/m2 to RVAW/m2 was quite good (P=<.001). RVAW/m2 appears to be more sensitive than RVIDd/m2 in the group studied, and becomes more sensitive with increasing age and severity of disease. This technique was easily performed in the younger age-group child (6-8 years), in those with markedly increased A-P chest diameters, and was not effort-dependent.It appears that echocardiography may be a valuable adjunct to other non-invasive techniques in the evaluation of these patients.