Echocardiographic Evaluation of the Right Atrial Area Index in Dogs with Pulmonary Hypertension.

BACKGROUND: Right atrial area (RAA) is a prognostic factor in human patients with pulmonary arterial hypertension (PAH). Reference intervals for RAA have been described in healthy dogs. OBJECTIVES: To evaluate RAA indexed to the body surface area in dogs with PAH as an indicator of right atrial size, PAH severity and right-sided congestive heart failure (R-CHF). ANIMALS: A total of 119 client-owned dogs, 48 dogs with PAH and 71 control dogs. METHODS: Prospective observational study. Pulmonary arterial hypertension was classified according to the tricuspid regurgitation pressure gradient (TRPG) as mild (36-50 mmHg), moderate (51-75 mmHg), or severe (>75 mmHg). The RAA index was calculated as the RAA divided by body surface area. RESULTS: The RAA index was higher in dogs with moderate PAH (13.3 cm2 /m2 ; range, 3.4-24.7 cm2 /m2 ) and severe PAH (12.1 cm2 /m2 ; range, 5.4-21.8 cm2 /m2 ) than in those with mild PAH (6.7 cm2 /m2 ; range, 4.8-10.7 cm2 /m2 ) or in controls (7.3 cm2 /m2 ; range, 4.2-10.2 cm2 /m2 ; P < 0.001). The RAA index was higher (P < 0.0001) in dogs with R-CHF (17.5 cm2 /m2 ; range, 12.7-24.7 cm2 /m2 ) compared to those without R-CHF (7.6 cm2 /m2 ; range, 4.4-19.4 cm2 /m2 ). The most accurate cutoff value of the RAA index to identify R-CHF was >12.3 cm2 /m2 (sensitivity, 100%; specificity, 89.5%). In dogs with PAH, severity of tricuspid regurgitation (TR) was the only independent predictor of RAA index based on multivariate analysis (P < 0.02). CONCLUSIONS AND CLINICAL IMPORTANCE: The RAA index can be used to evaluate right atrial size in dogs and may be more effective than TRPG in predicting R-CHF in dogs with PAH. The severity of TR is the main determinant of the RAA index in dogs with PAH.

Echocardiographic recognition of mediastinal masses.

The aim of our study was to assess the ability of echocardiography to recognize mediastinal masses. We studied 50 patients: 25 with acute lymphoblastic leukemia, nine with lymphomas, four with pleural effusion and previously known neoplastic diseases, ten with nonlymphomatous mediastinal masses, and two with compression of the superior vena cava. In 33 of 50 patients, computed tomography (CT) showed mediastinal masses, and in one, an aneurysm of the thoracic descending aorta. All patients had previously had chest x-ray and two-dimensional echocardiographic (2-DE) examinations in order to recognize the presence of masses. Two-DE was found to have similar specificity (94.1 percent) but higher sensitivity (90.9 percent vs 60.6 percent) if related to radiographic examination. The positive predictive value was 96.7 vs 95.2 percent and the negative predictive value was 84.2 percent vs 55.1 percent. In particular, 2-DE was more useful than chest x-ray examination when a concomitant pleural or pericardial effusion was present. Moreover, abnormalities of cardiac function due to compression or infiltration and the follow-up of patients were better evaluated.

Echocardiographic detection of right-sided cardiac thrombi in pulmonary embolism.

Echocardiography has proved useful in detecting right-sided heart thrombi in cases of pulmonary embolization. We found echocardiographic evidence of right-sided cardiac thrombi in six of seven patients affected by pulmonary embolism referred to our hospital within the past five months. In one patient with clinical evidence of pulmonary and paradoxic embolization, echocardiography revealed, besides thrombi within the inferior cava and right atrium, a transient, wide, systolic movement of the valvula foraminis ovalis toward the left atrium, suggesting an interatrial communication that was confirmed by contrast echocardiography. Five patients had a good outcome, with disappearance of the thrombi following IV heparin therapy, and one patient died.

[Echocardiography in primary hypothyroidism. Study of 25 patients]. / Aspetti ecocardiografici nell'ipotiroidismo primario. Studio di 25 pazienti.

25 patients affected by Primary Hypothyroidism and a control group of 25 subjects were studied with M-mode and Two-dimensional echocardiography. In hypothyroid patients mean left ventricular and aortic root dimensions were normal compared to control subjects. Pericardial effusion was found in 22 out of 25 patients (88%). Septal hypertrophy was found in 12 hypothyroid patients (48%), only in 3 out of these 12 patients left ventricular posterior wall hypertrophy was found. A moderate left atrial enlargement was found in 7 out of 25 hypothyroid patients. Two-dimensional echocardiography revealed an uniform degree of parietal hypertrophy from the basal segments to the cardiac apex. Therefore the main echocardiographic findings in hypothyroidism are: presence of pericardial effusion and asymmetrical septal hypertrophy. No correlations between these echocardiographic findings and age of patients, severity of "biochemical" alterations and duration of the thyroid disease was observed.

Cardiac toxicity of 5-fluorouracil. Report of a case of spontaneous angina.

We report a case of a patient with colon carcinoma and liver metastasis who presented chest pain after 5-fluorouracil (5-FU) administration. Clinical electrocardiographic evolution was similar to that observed in Prinzmetal's angina, and chest pain promptly resolved with nifedipine. These data suggest that coronary spasm may be the cause of cardiotoxicity due to 5-FU, and that calcium antagonists may probably be used in the prevention or treatment of 5-FU cardiotoxicity.

[Severe cardiomyopathy in a woman with intermediate beta-thalassemia. Regression of cardiac failure with desferrioxamine]. / Severa cardiomiopatia in donna con beta-talassemia intermedia. Regressione dello scompenso cardiaco con desferrioxamina.

We describe a patient affected by intermedia beta-thalassemia who presented a severe heart failure when she was 27 years old. The heart failure and radiologic, electrocardiographic and echocardiographic manifestations of cardiomyopathy disappeared with desferrioxamine therapy.

Long-term maintenance therapy with prazosin in congestive heart failure.

We evaluated the effects of long-term maintenance therapy with oral prazosin (6-20 mg, mean 14 +/- 2 mg/d) in 14 patients with congestive heart failure. The patients were followed for 6 +/- 1 months. Eleven of the fourteen patients reported subjective improvement. Two patients required increased diuretics because of gain in body weight. Systolic blood pressure showed a slight but sustained decrease suggesting persistent vasodilator effect. Reductions in echocardiographic left ventricular end-diastolic (6.35 +/- 0.25-5.88 +/- 0.25 cm, p less than 0.05) and end-systolic (5.16 +/- 0.35-4.73 +/- 0.28 cm, p less than 0.05) diameters were observed at 2 months. However, the cardiothoracic ratio on chest x ray was unaltered. Maximum exercise tolerance time increased in eight patients (57%) during prazosin therapy. Improvement in exercise tolerance time was observed in patients with most marked clinical improvement, suggesting presence of cardiac reserve. Two patients died suddenly after reporting subjective improvement. This study shows sustained clinical improvement in most patients with heart failure treated with oral prazosin.

Comparison of haemodynamic effects of oral prazosin, oral hydralazine, and intravenous nitroprusside in same patients with chronic heart failure.

The haemodynamic effects of oral prazosin and hydralazine were evaluated in patients with refractory heart failure and compared with those of intravenous nitroprusside in the same patients. Both oral agents were well tolerated and appeared to have beneficial haemodynamic effects. Prazosin and hydralazine produced similar increases in cardiac output associated with a similar decrease in systemic vascular resistance. Prazosin and hydralazine produced similar increases in cardiac output associated with a similar decrease in systemic vascular resistance. Prazosin resulted in a more significant decline in left ventricular filling pressure and pulmonary vascular resistance than did hydralazine. Haemodynamic alterations induced by prazosin were similar to those induced by nitroprusside, which suggests a relatively balanced reduction of preload and afterload. With hydralazine, the increase in cardiac output without change in left ventricular filling pressure or pulmonary vascular resistance suggests minimal effect on preload but significant reduction in afterload.

Polymorphism in fowl serum albumin. VI. Changes in in vitro protein synthesizing activity in developing embryonic fowl liver.

Cell-free protein synthesizing systems were prepared from the livers of chick embryos at selected ages and the characteristics of individual fractions were compared. While polysomes showed decreasing size with older embryos, isolated polysomes did not differ significantly in amino acid incorporating activity when assayed with standard cell sap. When assayed with standard polysomes, cell sap activity decreased with increasing developmental age whether incorporation was measured using (3H)lysine, (3H)leucine, or [3H]aminoacyl-tRNA. Free amino acid concentrations in the cell sap showed reproducidble independent variation during development which was taken into consideration in calculating net amino acid incorporation. A larger increase in ribonuclease activity was observed during development; however, nuclease inhibitor activity was absent before day 15 but increased thereafter. Aminoacyl-tRNA sythetase activity did not vary significantly. It is proposed that the observed changes in the rate of cell-free protein synthesis result not only from increasing ribonuclease activity with increasing developmental age but also from changes in the activity of other soluble factors.