Effects of amlodipine on sympathetic nerve traffic and baroreflex control of circulation in heart failure.

Short-acting calcium antagonists exert a sympathoexcitation that in heart failure further enhances an already elevated sympathetic activity. Whether this is also the case for long-acting formulations is not yet established, despite the prognostic importance of sympathetic activation in heart failure. It is also undetermined whether in this condition long-acting calcium antagonists favorably affect a mechanism potentially responsible for the sympathetic activation, ie, the baroreflex impairment. In 28 heart failure patients (NYHA functional class II) under conventional treatment we measured plasma norepinephrine and efferent postganglionic muscle sympathetic nerve activity (microneurography) at rest and during arterial baroreceptor stimulation and deactivation induced by stepwise intravenous infusions of phenylephrine and nitroprusside, respectively. Measurements were performed at baseline and after 8 weeks of daily oral amlodipine administration (10 mg/d, 14 patients) or before and after an 8-week period without calcium antagonist administration (14 patients). Amlodipine caused a small and insignificant blood pressure reduction. Heart rate, left ventricular ejection fraction, and plasma renin and aldosterone concentrations were not affected. This was the case also for plasma norepinephrine (from 2.43+/-0.41 to 2.50+/-0.34 nmol/L, mean+/-SEM), muscle sympathetic nerve activity (from 54.4+/-5.9 to 51.0+/-4.3 bursts/min), and arterial baroreflex responses. No change in the above-mentioned variables was seen in the control group. Thus, in mild heart failure amlodipine treatment does not adversely affect sympathetic activity and baroreflex control of the heart and sympathetic tone. This implies that in this condition long-acting calcium antagonists can be administered without untoward neurohumoral effects anytime conventional treatment needs to be complemented by drugs causing additional vasodilatation.

Dissociation between muscle and skin sympathetic nerve activity in essential hypertension, obesity, and congestive heart failure.

Essential hypertension, obesity, and congestive heart failure are characterized by an increase in muscle sympathetic nerve activity. Whether in these conditions skin sympathetic nerve activity is also increased has never been systematically examined, however. In 10 untreated mild essential hypertensive, 12 untreated normotensive obese, 10 mild (New York Heart Association class II) heart failure, and 10 normotensive lean healthy control subjects, we measured beat-to-beat arterial blood pressure (Finapres technique), body mass index, and postganglionic sympathetic nerve activity in skeletal muscle and skin areas (microneurographic technique, peroneal nerve). The muscle and skin nerve measurements were made in a randomized sequence. All data were obtained with the subject supine in a quiet, semidark environment at constant temperature over two periods of 30 minutes each, separated by a 20- to 30-minute interval. Blood pressure was increased only in hypertensive and body mass index only in obese subjects. Muscle sympathetic nerve activity quantified as bursts/min was markedly and significantly (P<.01) greater in essential hypertensive (33.3+/-1.7), obese (42.2+/-2.8), and congestive heart failure subjects (55.8+/-4.3) in comparison with control subjects (23.9+/-1.6). This was the case also for muscle sympathetic nerve activity, quantified as bursts per 100 heart beats. In contrast, skin sympathetic nerve activity (bursts per minute) was superimposable in hypertensive, obese, heart failure, and control subjects, its ability to increase being documented in all four groups by the marked response to an acoustic stimulus. Thus, in various diseases, muscle but not skin sympathetic activity is increased, with the sympathetic activation not being uniformly distributed over the whole cardiovascular system.

Sympathetic control of circulation in hypertension and congestive heart failure.

Adrenergic overactivity is a common hallmark of both essential hypertension and congestive heart failure. Indirect and direct measures of sympathetic function have clearly shown that sympathetic activation characterizes essential hypertension. This adrenergic overactivity appears to be related to the severity of the hypertensive state, being detectable in its early stages and showing a progressive increase with the severity of the disease. Essential hypertension is also associated with an impaired baroreflex control of vagal activity, whereas baroreceptor modulation of sympathetic nerve traffic remains unaltered, although undergoing a resetting phenomenon. In contrast, secondary hypertension is not associated with an increased adrenergic activity, thus suggesting that an enhancement in efferent sympathetic outflow is a peculiar feature of essential hypertension. Congestive heart failure is a condition also characterized by sympathetic activation, whose degree is proportional to the clinical severity of the disease. This is paralleled by an impairment in arterial baroreceptor modulation of both vagal and sympathetic activity, thus suggesting that the adrenergic overactivity in congestive heart failure is triggered by a reduced afferent restraint on the vasomotor centre. Chronic angiotensin-converting enzyme inhibition reduces the degree of both sympathetic activation and baroreflex dysfunction occurring in heart failure patients, a finding which documents that the neurohumoral abnormalities can be at least partially reversed by pharmacologic treatment.

[Physiological and psychopathological aspects of eating behavior]. / Aspetti fisiologici e psicopatologici della condotta alimentare.

Eating behaviour variations are often observed in medical practice. Sometimes they are physiological manifestations, rarely they are paraphysiological, many times they amount to pathological behaviour. Their heterogeneity could account for treatment problems met by the family doctor. Our study was aimed to increase the family doctor's attention to the eating behaviour of their patients. Greater awareness in family doctors of problems in their patients' eating behaviour may be apt to lead to an improvement in dietary habits and consequently to greater psychologic and physical wellbeing of the patients.

[Suicide at the USSL No. 6 in L'Aquila. Prevalence of the event, clinical and personality correlations]. / Suicidio nella USSL n. 6 di L'Aquila. Prevalenza del fenomeno, correlati clinici e di personalità.

During the last 10 years, suicidal behaviour has become an important social and health problem. The paper identifies 55 cases of suicide registered at a local health unit in L'Aquila (98,751 inhabitants) during the period 1982-1987. It examines the social-demographic variables and the way suicide was carried out. A sample group of 12 cases was selected and the following aspects were examined: personality, psychiatric symptoms and other diseases, use of drugs, the relationship with the health system, drug abuse, familial tendency to suicide, life history, previous suicide attempts, and messages left before death. ISTAT tests concerning the report of death were used to collect data and semi-structured interviews were arranged with medical officers and the victim's relatives.

[Prognostic stratification of non complicated acute myocardial infarct. Usefulness of the dipyridamole test with ecg-echo-thallium 201]. / Stratificazione prognostica dell'ima non complicato. Utilità del test al dipiridamolo con ecg-eco-tallio 201.

84 patients (pts) with recent first uncomplicated myocardial infarction underwent during the early post-infarction period, dipyridamole (D) test (EKG-ECHO-THALLIUM) and coronary arteriography in order to verify its feasibility, safety and usefulness in the detection of residual jeopardized but viable myocardium and in the diagnosis of multivessel disease. 69 pts performed a pre-discharge exercise test. During the execution of D test no major side effect occurred. The D-Echo was positive for residual ischemia in 41 pts (48.8%), the D-Thallium in 49 pts (58.3%) and the exercise test in 30 pts (43.5%). Both the imaging techniques allow the recognition of viable myocardium within the infarct zone (homozonal positivity) or outside the infarct zone (heterozonal positivity). The sensibility and specificity for multivessel disease are, respectively: with D-echo 50% and 100%; with D-thallium 60% and 100%; with exercise test 48% and 63%. D test has better diagnostic accuracy than exercise test in detecting multivessel disease; in particular we emphasized the excellent specificity of D-echo and D-thallium test. Poliparametric approach with D-test and exercise test gives a better stratification of the ischemic post-infarction risk.