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Partial anomalous pulmonary venous return (PAPVR) is a congenital heart disease with a reported incidence of autopsied case. The location of the anomalous pulmonary venous return is usually the right atrium, superior vena cava (SVC), and sometimes the brachiocephalic vein, inferior vena cava (IVC) or coronary venous sinus. Recently we experienced a rare case of PAPVR showing anomalous right total pulmonary venous return to the azygos vein. Further more, downward translocation of the right upper lobe bronchus was evident. This rare case is reported along with a review of the related literature. (Internal Medicine 31: 1112-1116, 1992 Key words: pulmonary anomaly, cardiac anomaly Case Report A 57-year-old woman was found to have a chest roentgenogram abnormality in a mass examination in 1975, but she did not visit a hospital. On May 19, 1990, she visited our hospital because of a common cold. The chest roentgenogram abnormality was again pointed out, and the patient was admitted for detailed examination. On admission, she was asymptomatic with a tem perature of 36.4°C, pulse 78/min., and blood pressure 110/50mmHg. On examination, a midsystolic murmur (Levinell/VI) was auscultated at the parasternal 2nd intercostal space. There was no abnormality of peripheral blood cell count biochemistry, arterial blood gas analysis or spirometry. An electrocardiogram was also normal. A chest roentgenogram (Fig. 1) of posterioanterior view showed dilatation of the azygos vein and deformity of the right cardiac edge, and a lateral view showed a tumor shadow which was connected to a vessel behind the cardiac shadow. From the findings of the lateral view, we initially suspected pulmonary arterio-venous fistula. Next we performed chest computed tomography (CT) and mag netic resonance imaging (MRI). Chest CT scan (Fig. 2) showed that a large pulmonary vein was connected to the azygos vein and that the dilated azygos arch was connected to the SVC. These findings were more evident on chest MRI (Fig. 3) than on chest CT scan. From these data, we suspected PAPVR showing anomalous right pulmonary venous return to the azygos vein. Therefore we performed cardiac echography and transesophageal cardiac echography, but no abnormal findings were obtained except for dilated SVC. Next we performed Radioisotope (RI) (99mTc-Human serum albumin) angiocardiography, which showed disappear ance of RI flow in SVC probably due to increased blood flow in the azygos vein (Fig. 4). A lung time activity curve (Fig. 5) showed two peaks, suggesting a left-to right shunt. As the findings of RI angiocardiography also strongly suggested PAPVR showing anomalous venous return to the azygos vein, we performed cardiac catheterization (Table 1). O2 saturatin in the azygos vein was 97.4%, which is higher than normal. O2 saturation in the upper SVC was 54.6% and that in the lower SVC, 93.1%. O2 saturation step up in the SVC suggested left-to right shunt through the azygos vein. The pulmonary-to systemic blood flow ratio was 2.03, and the left-to-right shunt ratio was 53.1...

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The Bio 14.6 Syrian hamster provides a good model for experimental study of cardiomyopathy. Cardiac receptor binding sites (alpha-1-, beta- and calcium antagonists) were studied in early (21 days old) and late (70 days old) stages of cardiomyopathy. The effects of verapamil on histologic features and free radicals in the heart were studied. The number of alpha-1- and beta-cardiac receptor binding sites was significantly greater in the late stage of cardiomyopathy when compared with findings in normal golden hamsters used as controls. The calcium antagonist receptors were significantly increased in the early stage but alpha-1- and beta-receptors were not. Verapamil-treated hamsters received intraperitoneal injections of verapamil at a dose of 5 mg/kg per day for 70 days from age 20 days. The percent areas of fibrosis and calcification in the verapamil-treated group were significantly smaller than those in the control group. The concentrations of lipid peroxides in the whole heart and free radicals in the heart mitochondria were significantly higher in the cardiomyopathic hamsters, and verapamil inhibited the increase in free radical concentration in the hearts of these hamsters. This study confirms that the number of calcium channels is increased early in the course of cardiomyopathy in the Bio 14.6 Syrian hamster. A larger number of free radicals may participate in the accumulation of calcium and cell injury in the myocytes of these hamsters. Verapamil protects against myocardial damage and may do so by inhibiting voltage-dependent calcium uptake and by preventing cell injury from free radicals.

Possible receptor changes occurring after withdrawal of chronic nifedipine treatment or chronic propranolol treatment were examined by administering nifedipine (100 mg/kg per day) or propranolol (45 mg/kg per day) to rats for 2 weeks and then withdrawing treatment [3H]Nitrendipine and [3H]DHA binding were measured in membrane fragments of the ventricle. In propranolol-treated rats, 8 h after the last administration, the maximum binding for [3H]DHA was significantly increased from 79.9 +/- 8.0 to 139.8 +/- 12.8 fmol/mg protein (mean +/- S.E.); the dissociation constant was significantly increased from 4.9 +/- 0.7 to 10.7 +/- 1.2 nM. On the other hand, in nifedipine-treated rats, 12 and 48 h after the last administration, [3H]nitrendipine binding and [3H]DHA binding had not changed significantly. These results indicate that the mechanism of the calcium antagonist withdrawal syndrome may be different from that of beta-blocker withdrawal syndrome.