Different impact of carvedilol and transdermal scopolamine on cardiovascular performance of mild-moderate chronic heart failure patients: evidence of useful effects of scopolamine on tolerance to work load.

OBJECTIVES: To verify and compare the effects respectively exercised in chronic heart failure patients by transdermal, slow release scopolamine patch and by the beta and alfa adrenoreceptor blocker carvedilol upon the main indexes derived from maximal cardiopulmonary stress test, as well as from analysis of heart rate variability. METHODS: In each of 14 patients suffering from NYHA class II chronic heart failure, admitted to study, the maximal cardiopulmonary test and heart period power spectrum assessment were performed, firstly during usual therapy, then after 7 days of continuous adjunctive treatment with scopolamine patch, and, finally after 3 months of regular administration of oral carvedilol, added to the basal therapy. The need of time enough to the adaptation of the cardiovascular system against the carvedilol pharmacodynamics, together with the need of slow, progressive dose titration, caused that the onset of therapy with carvedilol was separated from assessment of its effects on ergometric and spectral parameters by an interval period of 3 months. RESULTS: During administration of low doses of scopolamine, the values of VO2max, exercise time and double product were respectively 24 +/- 5.3 ml/kg/min, 12 +/- 3 min and 23630 +/- 3760, and resulted significantly higher than basal (p < 0.05 in all cases) and carvedilol-related readings (p < 0.01 by comparisons with VO2max and double product; p < 0.05 by comparison with exercise time). Again during scopolamine, the total variance, LF and HF powers exhibited the values reported as follows: 1255 msec2 and, respectively, 430 and 250 msec2, thus exceeding significantly the basal levels (p < 0.05 from comparison with total power, p < 0.01 from comparisons with LF and HF bands) as well as the levels reached during adrenergic blockade with carvedilol (LF scopolamine vs LF carvedilol: p < 0.01; total power and HF scopolamine vs corrispective carvedilol values p < 0.05). Compared to the basal findings, the carvedilol induced a significant reduction in VO2max (p < 0.05), double product (p < 0.01), peack of heart rate (p < 0.05) and LF power (p < 0.05), and elicited no significant decreases in exercise time; similarly a weak, not significant surge was product by carvedilol in total and HF powers. CONCLUSIONS: Therefore, in patients with left ventricle asymptomatic dysfunction, the low doses of scopolamine potentiate simultaneously the spontaneous heart rare variability and cardiopulmonary maximal testing; whereas, the carvedilol acts upon LF oscillatory component only, the effects upon total variance and HF band being negligible; moreover, this drug depress the myocardial functional capability; in fact, the carvedilol has been demonstrated to produce a remarkable fall in VO2max, this significant reduction in O2 maximal uptake involving the poor rise in cardiac output during the effort or less effective O2 removal from capillary beds or both.

[The dobutamine-dopamine combination versus amrinone in congestive heart failure with a marked edematogenic sign complicated by functional kidney failure. A comparison between 2 different models of inotropic stimulation and diuresis potentiation]. / Associazione dobutamina-dopamina versus amrinone nello scompenso cardiaco congestizio a marcata impronta edemigena complicato da insufficienza renale funzionale. Confronto tra due diversi modelli di stimolazione inotropa e di potenziamento della diuresi.

BACKGROUND: We evaluated the diuretic output in patients with decompensated chronic heart failure (CHF), previously treated by i.v. infusion with dobutamine and dopamine (dob-dop) or with amrinone (amr). Our target was to identify the possible discrepancies in urinary output perhaps linked to the different type of inotropic stimulation in the two subsets. METHODS: Adjunctive therapy with dob-dop or amr was chosen because the administration of diuretics only, without cardiac support, as tested in previous hospitalizations, had been demonstrated to produce unfavourable results, mainly expressed by finding of a low output syndrome in 50% of cases or more. The administration of i.v. infusion was maintained during 17 hours (1000 min approximatively), and included infusion in separate pumps of the two amines, dobutamine at dose of 5 micrograms/kg/min and dopamine at dose of 2.8 micrograms/kg/min or, alternatively, i.v. infusion of amr, administered at dose of 7 micrograms/kg/min. Infusion volumes were similar in the two subsets. The two subsets were homogeneous relatively to renal impairment, i.e. to the parameters (urinary Na, U/P creatinine, U/P urea, urinary osmolality) we fixed as markers idoneous to demonstrate the occurrence of organic renal damage (acute tubular necrosis). RESULTS: The diuresis was recovered in all 24 patients, and the urine volume resulted more pronounced in the subset attributed to the dob-dop at both the 8th and the 17th hour readings. We found no harmful alterations in HR and AP, whereas renal function parameters have been shown to enhance in both the dob-dop and amr arms. The diuretic effectiveness of the SIEV obtained by catecholamine implementation exercised a synergistic, favourable effect on diuresis, renal flow, glomerular filtration rate, and sodium post-proximal delivery. Amr resulted less effective then dob-dop simultaneous administration relatively to the diuretic effect. No remarkable differences were found in the two subsets as regards the heart rate, whereas a decrease in arterial pressure was found after amr. A persistent shift towards a condition of chronic renal failure, was identified in 4/24 patients, the two groups despite of the prolonged treatment at optimized doses: no remarkable side effects were reported. CONCLUSIONS: Thus, the selective effect upon renal hemodynamics, as exercised by dob-dop infusion low doses of dop, together with the enhanced renal output due to dob, has been shown to be more effective than amr influence: thus, the catecholamine therapeutical approach has been demonstrated to possess the best effectiveness in excitation of diuresis, among the CHF oliguric patients.

[Evaluation of the effect of picotamide on platelet function in diabetic subjects]. / Valutazione degli effetti della picotamide sulla funzione piastrinica in soggetti diabetici.

In this study the Authors verify the results of Picotamide on platelet aggregation in diabetic subjects. The results suggest that Picotamide has no influence on insulin or oral treatment of diabetic subjects. However, it is certain that platelet aggregation by ADP or collagen decreases due to the effect on thromboxane probably because of the limitation of platelet receptors.