Tocainide and metoprolol: an efficacious therapeutic combination in the treatment of premature ventricular beats

A double-blind crossover study was performed in 20 patients to verify the efficacy of tocainide plus metoprolol in patients with premature ventricular contractions (PVCs) class Lown greater than or equal to 2 (mean frequency greater than or equal to 30/h) judged as being "stable" by at least three basal 24-h Holter ECGs with PVC variation of less than +/- 25%. All 20 patients were submitted to a placebo period; and all were subsequently randomized to therapy with tocainide 1800 mg/day or metoprolol 200 mg/day for 15 days and then to tocainide 1800 mg + metoprolol 200 mg/day or tocainide 1200 mg + metoprolol 200 mg/day for 15 days, followed by a crossover of the two combination treatments. At steady state in every stage we controlled for plasma levels of the drugs, a 24-h Holter recording, and a 12-lead ECG. A modified Lown score was evaluated together with the Lown class. Tocainide (mean plasma level 3.3 +/- 0.7 micrograms/ml) was efficacious in 3 of 8 patients, the modified Lown score decreased from 63 +/- 32 (placebo period) to 42 +/- 27 (p less than 0.01) and Lown 4B arrhythmias were abolished in 3 of 4 patients. Metoprolol (mean plasma level 97.4 +/- 89.6 ng/ml) was efficacious in 2 of 10 patients; the modified Lown score and Lown classes did not change significantly. Administration of tocainide 1200 mg + metoprolol 200 mg obtained a positive response in 9 of 12 patients, the modified Lown score decreased significantly compared with placebo (from 53 +/- 31 to 32 +/- 30, p less than 0.01) and Lown 4B arrhythmias were abolished in 2 of 5 cases. Tocainide 1800 mg plus metoprolol 200 mg was scarcely tolerated owing to neurologic and gastroenteric side effects, and only three patients completed this stage with no better antiarrhythmic results compared to the lower dose. In conclusion, the combination of tocainide at 1200 mg and metoprolol 200 mg is well tolerated, efficacious in a high percentage of patients, and superior to single drug therapy in patients with stable PVCs.

Plasma concentrations of atrial natriuretic factor in normal pregnancy and early puerperium

The atrial natriuretic factor (ANF) and parameters related to renal sodium handling and renal function were evaluated in 92 normotensive pregnant women at different gestational ages (1st group: 7th-13th week, 2nd group: 14th-20th week; 3rd group: 21st-27th week; 4th group: 28th-34th week; 5th group: greater than 34th week), in 15 normotensive non-pregnant women and in 15 normotensive women 6 days after spontaneous delivery at the end of a normal pregnancy. ANF did not differ significantly between the 5 groups of pregnant women while, concurrently with a further increase in plasma volume (as shown by our data) it was significantly higher in late pregnancy (3rd and 5th groups) than in the non-pregnant women. ANF in post-partum women was significantly higher than in non-pregnant and pregnant women. Only in post-partum women was ANF significantly directly related to sodium excretion. Even though ANF does not seem to play an important role in water and sodium excretion in pregnancy in comparison with other hormones such as progesterone, oestriol and aldosterone, the higher levels of ANF in late pregnancy probably represent a compensatory increase when a given threshold of plasma volume (and therefore of atrial stretch) is reached. However ANF does seem to play a more important role in the induction of diuresis and natriuresis in early puerperium.

Characterization of a Na+/K+-ATPase inhibitor from human plasma: preliminary data

The role of an endogenous sodium pump inhibitor in the pathogenesis of hypertension has been reported in several papers. Unfortunately, because of the unknown structure and lack of biochemical characterization, some discrepancies have arisen. In this study we report a method to obtain extracts from human plasma that are able to inhibit Na+/K+-ATPase in vitro. Preliminary characterization was carried out, which showed that the extracts are able to inhibit Na+/K+-ATPase, pNPPase, and [3H]ouabain binding to red blood cells. The enzyme inhibition is not due to vanadate, FFA, or bivalent cations, and it seems to be reversible, dose-dependent, and largely prevented in E1 conformation of the enzyme. These results seem to support the hypothesis that human plasma contains a sodium pump inhibitor with many characteristics of a "ouabainlike" compound.

Importance of plasma renin activity suppression and venous distensibility on pressor and natriuretic responses to intravenous salt load in borderline hypertension

Cardiopulmonary receptors influence renin release in a variety of physiological situations and in a fashion related to the degree of peripheral venous distensibility. We studied two groups of borderline hypertensives (BHTs) with different capacities to suppress plasma renin activity in response to saline infusion (0.20 mL/kg/per minute for 2 hours). Those BHTs with low suppressive capacity (L-supp) showed an increased venous distensibility in comparison with those with high suppressive capacity (H-supp). Saline infusion led to a significant increase in blood pressure only in L-supp BHTs, which was associated with enhanced 24-hour postloading natriuresis and raised plasma levels of an Na/K ATPase inhibitor (+12.2%). This result underlines the importance of venous distensibility as a determinant of pressor and humoral response to acute volume expansion.

Impaired vasodilator capacity and exaggerated pressor response to isometric exercise in subjects with family history of hypertension

The nature of the cardiovascular response to isometric exercise is still debated. An adequate blood supply to exercising muscles at the onset of contraction seems to be an important factor controlling the extent of pressor response to isometric contraction. In comparison to normotensive subjects without familiar hypertensive history (F-), normotensive subjects with family history of hypertension (F+) have a reduced peripheral vasodilator capacity which impairs the possibility to adjust the muscular blood flow during exercise. An enhanced pressor response to handgrip test was observed in F+ and this hyperresponsivity was inversely related to the extent of forearm vasodilation capacity and largely prevented by the pretest increase of blood flow in exercising muscles. Our results suggest the importance of local vasodilating capacity as a determinant of reflex pressor response to isometric exercise.

Erythrocyte Na-K-ATPase membrane activity in obese patients fed over a long-term period with a very-low-calorie diet

In a search for the role of long-term hypocaloric feeding on the expression of the erythrocyte Na pump in obesity, we examined three groups of subjects. Group 1 consisted of 10 obese subjects who had been under treatment for a long period of time with a very-low-calorie diet (500 kcal/d) while group 2 consisted of 10 age-, sex-, and body mass index-matched obese subjects on their usual diet; in the third group, 12 normal-weight subjects on a free diet served as controls. There was no difference between the groups in the number of erythrocyte binding sites per cell. On the contrary, the Na-K-ATPase activity was significantly lower in the obese group 1 (0.35 +/- 0.09 mumol Pi x mg protein-1 x h-1) compared to that observed in the obese group 2 (0.42 +/- 0.07, P less than .05) and in control subjects (0.45 +/- 0.06, P less than .05). Sex, duration of hypocaloric feeding, and the amount of weight loss before the study in the obese group 1 seemed not to be related to the Na pump parameters. We conclude that long-term severe hypocaloric feeding may be a factor in altered erythrocyte Na-K-ATPase in obese individuals.

Ciclosporin A: correlation of blood levels with acute graft-versus-host disease after bone marrow transplantation

Thirty patients undergoing allogeneic bone marrow transplantation (BMT) for hematologic malignancies received ciclosporin A (CS-A) as prophylaxis of graft-versus-host disease (GVHD). CS-A trough levels were determined in whole blood by radioimmunoassay (RIA); results were not used to adjust the CS-A dosage. Neither the dose of CS-A administered nor the CS-A concentration and fluctuation of blood levels during the first 15 days after BMT correlated with acute GVHD. Conversely in the 13 patients with acute GVHD, CS-A concentrations in the 10 days prior to the onset of the disease were increasingly lower with increasing severity of GVHD. Moreover, patients without GVHD had higher CS-A concentrations in a matched period of time. Upon withdrawal of CS-A treatment, 7 patients developed GVHD. There was no possibility to predict who would do so, but the analysis of CS-A disappearance profiles indicates that effective CS-A concentrations might be lower during long-term treatment than the concentrations required early after transplant. Despite these relationships, CS-A concentration is of little predictive value in the individual patient because of the considerable overlap among patients.

Retrograde spread of 5-aminosalicylic acid enemas in patients with active ulcerative colitis

In an attempt to know the exact retrograde spread of high-dosage 5-aminosalicylic acid enemas, we have studied eight patients with active left-sided colitis, by adding a small amount of barium sulfate to the enemas and by checking the spread radiologically after 15 minutes, 1 hour, and 6 hours. Four grams of 5-aminosalicylic acid in 100-ml enemas and 4 gm in 200-ml enemas were used. The same experiment was repeated in a subsequent attack, with enemas labeled with technetium-99m and checked by scintiscans in five of these patients. We always have observed a volume-dependent spread of enemas but, interestingly, in the patients studied with technetium-99m there was always a wider spread than that which was detected with barium enemas. In all five patients, 100-ml enemas reached the splenic flexure. In two patients with total colitis, a progression of 100-ml technetium-99m enemas was performed in the transverse colon, but the maximum opacity remained in the left side. We can conclude that 4 gm of 5-aminosalicylic acid in 100-ml enemas can be suitable for treating patients with left-sided colitis, and will represent a valid addition for patients with more extensive colitis.

Cellular and humoral factors in borderline hypertension

In this article, we review the data about Na+ and K+ lymphocyte content in young subjects with borderline hypertension. These data indicate that many borderline subjects have an abnormally high lymphocyte Na+ content (Nai) and that their pressor response to stress and exercise is directly related to Nai. Lymphocyte K+ content (Ki) is increased in about 50% of borderline subjects. Subjects in whom Ki is high, in comparison with those having a normal Ki, have a lower Nai and lower diastolic blood pressure. This suggests that these subjects have an activation of some compensatory mechanism, possibly an increase in sodium pump function. A humoral factor causing an increase in Nai was detected not only in the plasma from essential hypertensives, but also in the plasma from borderline subjects and from normal subjects with familial hypertension having high Nai. This indirect evidence of a plasma factor impairing Na+ transport was confirmed by direct measurements of the plasma ability to inhibit Na+/K+ adenosine triphosphate. Moderate short-term dietary salt restriction reduces Nai and, proportionally, pressor response to stress. In the long-term, resting blood pressure is also reduced. Dietary K+ supplementation reduces pressor response to handgrip but not resting blood pressure. Intralymphocytic Na+ content is a good predictor of future sustained hypertension, since subjects with normal Nai do not develop hypertension within 5 years, whereas subjects with high Nai develop hypertension in 31% of cases. These subjects also have an altered pressor response to mental stress and do not respond to the low-salt diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Predictors of stable hypertension in young borderline subjects: a five-year follow-up study

Forty-four young subjects with borderline hypertension underwent a 5-year follow-up. At the first examination their intralymphocytic Na+ (Nai) was measured before and after 1 month of a low-salt diet. Blood pressure and heart rate were recorded at rest (baseline), during mental arithmetic, and after the test (recovery). After 5 years, no subject with normal Nai developed hypertension, and, furthermore, subjects with normal Nai had no increase in blood pressure values. Thirty-one percent of subjects with high Nai developed hypertension. Subjects developing hypertension were characterized by a high pressor response to mental stress and by an increase in recovery diastolic blood pressure in comparison with baseline diastolic blood pressure. Sixty percent of the subjects whose recovery diastolic blood pressure was at least 6% higher than baseline developed hypertension. Eighty percent of subjects whose Nai was not reduced after the diet became hypertensive. Nai and diastolic blood pressure were unrelated at the first examination; however, a significant correlation was found between Nai recorded at first examination and diastolic blood pressure recorded after 5 years. It is concluded that Nai is a good predictor of future blood pressure in borderline subjects and that subjects with normal Nai have a very low risk of developing high blood pressure.

Modifications of intra- and extracellular sodium and potassium. A possible mechanism for the antihypertensive action of captopril and hydrochlorothiazide

Forty-four essential hypertensive patients were studied during placebo and after 2 months of the following treatments: hydrochlorothiazide 25 mg once daily (group 1); captopril 50 mg twice daily (group 2); hydrochlorothiazide + captopril (group 3). Blood pressure, serum sodium and potassium (Nae, Ke) and intralymphocytic sodium and potassium (Nai, Ki) were measured before and after treatment. During placebo, diastolic blood pressure was directly related to Nai (r = -0.84) and inversely related to Ki (r = -0.81). The correlation was even greater when the Ki:Ke ratio was considered instead of Ki alone (r = -0.91). Hydrochlorothiazide reduced Nai, Ke and Ki. Captopril induced a decrease in Nai, an increase in Ki and no change in Nae or Ke. The association of the two drugs caused a reduction in Nae and Nai and an increase in Ki. All three treatments caused an increase in Ki:Ke ratio which was proportional to the decrease in the blood pressure. While the antihypertensive effect of hydrochlorothiazide seems to be more related to Nai:Nae reduction, the effect of captopril seems to be more related to the increase in Ki:Ke ratio. The results of our study suggest that hyperpolarization of arterial smooth muscle cells, induced by a Ki:Ke ratio increase, along with a reduction in Nai:Nae, might play a role in the antihypertensive effect of captopril and hydrochlorothiazide.

[Primary angiosarcoma of the right atrium invading the pericardial cavity. Description of a case diagnosed by exploratory thoracotomy and surgically treated with success]

The AA. report the case of a 43-year-old woman with an angiosarcoma arising from the right atrial wall and growing into the pericardial cavity. The patient presented with recurrent pericardial effusion initially responsive to medical therapy. The diagnosis was made at the exploratory thoracotomy. Repeated 2D-Echocardiograms did not help for the diagnosis in this particular case. The patient underwent surgical resection of the tumor, chemo- and radiotherapy. After 30 months there are no signs of recurrence or metastasis. In our opinion the frequent recurrence of pericardial effusion in the same patient should be regarded with special suspicion.

Topical administration of 5-aminosalicylic acid enemas in patients with ulcerative colitis. Studies on rectal absorption and excretion

5-aminosalicylic acid (5-ASA) is a new treatment for patients suffering from ulcerative colitis but only limited information is available about its rectal absorption. We therefore studied seven patients with ulcerative colitis in remission, and five with active disease to determine acetylated and free 5-ASA plasma concentrations and urinary acetyl 5-ASA after the administration of three different types of enemas: (2 g 5-ASA/100 ml, 4 g/100 ml, and 200 ml). In patients in remission urinary acetyl 5-ASA excretion was dose and volume dependent (p less than 0.01; p less than 0.05) but this correlation was absent in active disease. Because aminosalicylates are usually eliminated through the kidney, these low values (10% in active disease and 19% in those in remission) suggest that the beneficial action may be local. Urinary recovery was significantly lower in patients with active disease (p less than 0.01; p less than 0.02). No accumulation of 5-ASA was found in plasma after repeated daily administration.

Differing dosages of captopril and hydrochlorothiazide in the treatment of hypertension: long-term effects metabolic values and intracellular electrolytes

The effects of long-term treatment with differing dosages of captopril and hydrochlorothiazide in combination were evaluated in 22 hypertensive patients. There was no significant difference in antihypertensive efficacy between captopril 25 mg twice a day in combination with hydrochlorothiazide 25 mg once or twice daily and captopril 50 mg twice a day in the same combination. About 75% of patients achieved normotension. Once daily therapy with captopril 50 mg and hydrochlorothiazide 25 mg was effective in only 25% of patients. Long-term treatment (11 months) with captopril and hydrochlorothiazide did not cause any of the metabolic effects usually observed during diuretic administration. Intracellular (lymphocytic) Na+ was significantly reduced and intracellular K+ significantly increased by captopril and hydrochlorothiazide, and this led to the normalization of the intracellular Na+:K+ ratio, which is abnormally high in essential hypertension. Our data suggest that the association of low doses of captopril and hydrochlorothiazide is highly effective, well tolerated, prevents the metabolic side effects of diuretics, and has favorable effects on intracellular ionic composition.

Plasma Na+-K+ ATPase inhibitory activity in normal and hypertensive subjects: relationship to intracellular electrolytes and blood pressure

The ability of plasma extracts to inhibit Na+-K+ ATPase in vitro (P.I.A.) was tested in 20 normotensives, 10 without (F-) and 10 with (F+) familial hypertension, in 20 borderlines (BL) and in 21 essential hypertensives (EH). In these subjects we also measured intralymphocytic sodium (ILSC) and potassium (ILKC) content, P.R.A. urinary aldosterone and Na+(Na+u), and blood pressure. P.I.A. of EH, BL and F+ subjects was significantly higher than that of F-. 60% of EH and BL and 40% of F+ had P.I.A. values greater than the highest found in F-. P.I.A. was significantly related to mean blood pressure (r = 0.63), to ILSC (r = 0.56), to ILKC (r = -0.56), to ILSC/ILKC ratio (r = 0.71) and to Na+u (r = 0.39) but not to P.R.A. or aldosterone. These data demonstrate that plasma extracts from young subjects prone to hypertension may inhibit sodium pump and that this inhibitor may affect blood pressure by altering the Na+/K+ intracellular ratio.

Pharmacokinetics and placental transmission of fazadinium in elective caesarean sections

The pharmacokinetics and placental transmission of fazadinium (0.75-0.80 mg kg-1) were studied in seven pregnant women undergoing elective caesarean section. Plasma levels of the drug were determined by a spectrofluorimetric method and pharmacokinetics were derived according to a 2-compartment open model. Distribution and elimination half-lives averaged 0.07 +/- 0.03 (t1/2 alpha) and 1.24 +/- 0.34 (t1/2 beta) h; the volume of distribution was 20.75 +/- 5.81 1, and the plasma clearance was 202.33 +/- 39.2 ml min-1 1.73 m2. The ratio between umbilical venous blood and maternal blood at delivery ranged from 2.57 to 17.5%. Urinary elimination accounted for 37% of the injected dose within 24 h. It is concluded that because of early good intubating conditions and favourable pharmacokinetics with a modest placental passage, fazadinium might be particularly useful in obstetrics.

Comparison of two methods for the evaluation of renal perfusion

The validity of a single blood sample technique at the 44th min after the injection of OIH for the evaluation of effective renal plasma flow was assessed by comparison with a standard clearance method, based on two-compartment analysis of plasma disappearance of the tracer. The simplified method tended to overestimate the true values; the 95% confidence interval for the error in predicting the true value was found to be +/- 88 ml/min. Overall, the simplified method appears to be adequate to study renal perfusion or its changes in different conditions, but due to the predicting error it requires a larger number of patients, as compared with the reference method, in order to obtain statistically valid results.

[Behavior of plasma and urinary cAMP after intravenous fructose load]

Increased excretion of uric acid and cAMP has been observed in many pathological conditions in man, but interrelation between behaviour of uric acid and cAMP is not well known. To investigate these aspects of purine metabolism the authors have studied behaviour of plasma and urinary cAMP in 8 subjects after intravenous rapid load of fructose (0.5 g/Kg b.w.) compared with the uric acid one. The results have shown that urinary excretion of cAMP after load of fructose is increased, but levels of plasma cAMP remain unchanged. These data confirm consensual relation between urinary uric acid and cAMP excretion, but the exact mechanism of this relation remains unexplained.

[A rapid method for assay of 25-hydroxyvitamin D in serum]

A simplified assay for 25-hydroxyvitamin D is reported. In this procedure ethanol extraction is used in order to obtain a better protein precipitation and a higher recovery of added tritiated 25-hydroxyvitamin D3. Extraction is followed by column chromatography on Sep-pak Silica cartridges. The eluate is dried and directly used for competitive protein binding assay. The method shows two main advantages: it is less time consuming and is easier to perform than existing procedures.

[Assay of 24,25-dihydroxyvitamin D by competitive protein binding]

A competitive protein binding radioassay for 24,25-dihydroxyvitamin D in human serum has been developed, which is relatively simple and rapid. Acetonitrile is used for sample extraction and protein precipitation. column chromatography is then performed in a Sep-pak cartridge. High pressure liquid chromatography follows. The dried eluate is assayed using rat serum as the source of binding protein. Since 25-hydroxyvitamin D3 and 24,25-dihydroxyvitamin D3 are equipotent in their competitive displacement of tritiated 25-hydroxyvitamin D3 from at serum, 25-hydroxyvitamin D3 can be used as the assay standard.

[Acute Candida arthritis. Isolation of Candida krusei in a heroin addict]

Candida arthritis in men is very rare. In most cases Candida albicans is isolated from joints (commonly the knee) of immature infants or of immunodeficient subjects without underlying joint disease; Candida non albicans is isolated from joints of immunodeficient patients with underlying joint disease. A case of Candida arthritis in a heroin addict is described. This is the second report of Candida arthritis in a heroin addict, but it is the first in which Candida krusei has been isolated.

[Unilateral rheumatoid arthritis]

The authors describe a case of left monolateral rheumatoid arthritis of a patient who nine years previously presented ischemic cerebral lesion resulting in right emiparesis. It should be noted that rheumatoid arthritis appears clinically and radiologically monolateral, whereas from a histological viewpoint the lesions are always bilateral. This brings to mind previously advanced hypothesis to explain this rare expression of rheumatoid arthritis. In conclusion the main factor for articular protection is the rest period induced by the stroke.