Aims It has been previously hypothesized that the adverse outcome observed in depressed patients after myocardial infarction might be due to an imbalance in autonomic nervous system activity. The aim ...of this study was to define the role of depressive and anxious symptoms in influencing autonomic control of heart rate after myocardial infarction. Methods and Results The SD of RR intervals, baroreflex sensitivity, and depression and anxiety (Zung’s scales) were assessed before discharge in 103 patients with acute myocardial infarction; 32 were found to be depressed. Among the patients who were not taking β-blockers, those with depression had significantly lower SDs of RR intervals and baroreflex sensitivity than did those without depression (96.3 ± 22.2 ms vs 119.5 ± 37.7 ms, P =.016; 8.6 ± 6.2 ms vs 11.8 ± 6.5 ms/mm Hg, P =.01, respectively). No differences were found when anxiety was considered or when β-blockers were given. Among the patients not taking β-blockers, there was a significant correlation between depression levels and both the SD of RR intervals (r = –0.47) and baroreflex sensitivity (r = –0.40). Conclusions In patients with myocardial infarction, depression but not anxiety negatively influences autonomic control of heart rate. β-Blockers modify these influences. (Am Heart J 2001;141:765-71.)
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
To explore the role of heart rate in the genesis of ventricular premature complexes whose incidence increases when the length of the preceding cardiac cycle decreases, we analyzed the effect of ...nadolol alone and together with atrial pacing in 4 patients. Nadolol lengthened the RR cycle and suppressed ventricular premature complexes; atrial pacing, restoring the baseline RR cycle lengths, led to the reappearance of ventricular premature complexes, suggesting the major role of heart rate.
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IJS, IMTLJ, KILJ, KISLJ, NUK, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Raynaud's phenomenon is defined by an intermittent vasospasm of the arterioles of the distal limbs. Helicobacter pylori infection has been recently associated with Raynaud's phenomenon. The aim of ...this study was to assess the effects of H. pylori eradication on Raynaud's attacks. Forty-six patients affected by primary Raynaud's phenomenon were evaluated. H. pylori infection was assessed by 13Curea breath test. Eradication therapy was given to infected patients for seven days. Discomfort and the duration and frequency of attacks of Raynaud's phenomenon per week were assessed. Thirty-six subjects were infected with H. pylori; the bacterium was eradicated in 83% of these after therapy. Attacks of Raynaud's phenomenon completely disappeared in 17% of the patients with H. pylori eradication. Discomfort and the duration and frequency of attacks of Raynaud's phenomenon were significantly reduced in 72% of the remaining patients. Conversely, attacks of Raynaud's disease did not change significantly during the 12-week follow-up period either in the H. pylori-negative patients or in the infected subjects in whom the bacterium was not eradicated by therapy. The study shows that H. pylori eradication causes a significant decrease in clinical attacks of Raynaud's disease. The reduction of vasoactive substances determined by the eradication of the bacterium may be the pathogenetic mechanism underlying the phenomenon.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
To identify a method for characterizing the dynamic behavior of ventricular arrhythmias at different heart rates, 201 consecutive patients with frequent premature ventricular contractions (PVCs) ...underwent two 24-hour electrocardiographic monitoring periods. The percentage of PVCs for each cycle length was calculated and then analyzed by linear regression analysis. On the basis of the significance of the
p value, and the positive or negative value of the slope, we identified three trends: a tachycardia-enhanced pattern (
p < 0.01, slope negative), a bradycardia-enhanced pattern (
p < 0.01, slope positive), and an indifferent pattern (
p > 0.01). During the first monitoring period, a tachycardia-enhanced pattern was present in 56 patients (28%), a bradycardia-enhanced pattern was present in 49 patients (24%), and an indifferent pattern was present in 96 patients (48%). This relationship was reproducible in 41 of the patients with a tachycardia-enhanced pattern (73%), in 29 of the patients with a bradycardia-enhanced pattern (59%), and in 70 patients with an indifferent pattern (72%). In conclusion, it is possible to identify a spontaneous trend between the incidence of ventricular arrhythmias and the length of the preceding cardiac cycle that seems to remain stable over time. (Am Heart J 1997;133:153-61.)
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IJS, IMTLJ, KILJ, KISLJ, NUK, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The aim of this study was to assess the blood pressure profile of chronic renal failure in comparison with essential hypertension. Thirty hypertensive patients with chronic renal failure due to ...non-vascular nephropathies were matched by age, sex, and mean 24 h blood pressure, with 30 patients affected by uncomplicated mild-to-moderate essential hypertension. They were studied in an open hospital ward. Diet, meal times, sleep times, and activity schedules were standardized. Noninvasive, automatic, blood pressure recordings were performed for 48 h at sampling intervals of 15 min. The mean 24 h blood pressure almost coincided in the two groups. However, in essential hypertension a mean (+/- SD) nocturnal fall of systolic and diastolic blood pressure was found (12.7 +/- 3.8 and 12.9 +/- 4.8 mm Hg, respectively), while renal patients displayed an average nocturnal increase of 2.7 +/- 8.9 mm Hg and 3.7 +/- 7.8 (P less than .001). The renal patients had also higher heart rates, with a significantly blunted nocturnal fall (4.4 +/- 4.5 beats/min as compared to 9.3 +/- 3.1 beats/min of essential hypertension; P less than .001). Among the renal patients, the day-night blood pressure changes showed no significant correlation with age, creatinine clearance, hematocrit, nocturnal change in heart rate, or day or night mean blood pressure levels. These data suggest that an abnormal day-night pattern of blood pressure is present in chronic renal failure patients independently from external interfering factors. Hence, casual measurements of blood pressure confined to daytime may underestimate a hypertensive condition associated with chronic renal failure.
Previous studies suggested that in patients with hyperthyroidism an autonomic imbalance and in particular a lower than normal vagal activity might be present. To verify this hypothesis we have ...evaluated the respiratory sinus arrhythmia (RSA, a measure of cardiac vagal activity) in ten hyperthyroid patients and in ten normal subjects. RSA was calculated from the power of the spectral component of the heart rate variability in high frequency band (HF–RR) during both spontaneous (supine and passive head-up tilt) and controlled breathing (supine). During controlled breathing the phase relation between heart rate and respiratory has been computed. The hyperthyroid patients showed a higher heart rate in all three conditions (
P<0.001) and higher spontaneous respiratory rate in supine position (centered frequency of HF–RR: 0.342±0.015 vs 0.262±0.016 Hz;
P<0.001). No difference was found in hyperthyroid patients compared to controls in terms of the HF–RR power in normalized units both during spontaneous breathing (supine, 43±8.3 vs 39.7±6.7%; tilt 18.8±5.9 vs 19.3 vs 4.1%; mean ± SE) and controlled breathing (45.4±7.1 vs 48.9±6.9%). No difference was found also in terms of the phase relationship between the heart rate and the respiratory signals (77.5±32.3 vs 77.5±28.1, degrees). Hyperthyroid patients seem not to have an impaired cardiac vagal activity.
The natural evolution of ventricular arrhythmias complicating a first episode of acute myocardial infarction has been studied in a group of 56 consecutive patients, who were admitted to the Coronary ...Care Unit within three hours of the onset of symptoms, and in whom drug administration (digitalis, antiarrhythmics, diuretics and heparin) was limited. Ventricular arrhythmias have been evaluated by means of Holter monitoring performed during the first 24 hours, the second 24 hours, the eighth day, the 18th day and two years after discharge when antiarrhythmic drugs has been discontinued for at least five half-lives. The overall incidence and prevalence of ventricular arrhythmias showed a steady and statistically significant reduction from the first to the eighth day, and a not statistically significant increase from the eighth to the 18th day. The latter increase was still present at the two-year follow-up. The one-by-one behaviour analysis of discharged patients delineated three different patterns: patients who presented a steady reduction in ventricular arrhythmias from the first to the 18th day (44%); patients who showed an almost constant incidence of ventricular arrhythmias during all phases of acute myocardial infarction (24%); and patients who presented both a decrease and an increase in their ventricular arrhythmias (31%). The follow-up at two years showed that the majority of patients, especially those discharged in a high Lown class, had the same arrhythmias as at their follow-up on the 18th day. Correlation of ventricular arrhythmias with the extent of the infarcted area demonstrated that only the peak and mean values of lactic dehydrogenase correlated with the severity of ventricular arrhythmias.
Transdermal clonidine (TTSC) treatment was evaluated in 29 patients with mild to moderate hypertension scheduled for minor surgery. Two weeks before the scheduled operation, patients underwent 24-h ...ambulatory blood-pressure monitoring (ABPM) to evaluate the efficacy of previous oral antihypertensive treatment, which was then substituted with TTSC, 0.1 mg/day. After 1 week, the efficacy of TTSC was clinically assessed, and the dose increased to 0.2 mg/day if needed. ABPM was repeated 2 days before the scheduled operation and 2 days after surgery. The 24-h blood pressure (BP) and heart rate (HR) profiles were smoothed by Fourier analysis. Three patients withdrew for adverse events and one for inefficacy after dose adjustment, TTSC being effective in the remaining 25 patients. Two patients who completed treatment lacked postsurgical ABPM recording. In the 23 patients with all ABPM recordings, average 24-h BP and HR obtained preoperatively during TTSC treatment were slightly reduced compared with values recorded during previous oral therapy. BP changes after surgery were negligible, whereas HR showed a moderate increase. Minor adverse events occurred in four (14%) of 29 patients. Our results demonstrate that TTSC provides adequate BP control in patients with mild to moderate hypertension undergoing minor surgery.
Six normal women, in the follicular phase of their menstrual cycle, and 6 normal men received orally 40, 60 and 100 mg doses of piribedil, a dopamine receptor agonist, or placebo. The effects of ...piribedil on anterior pituitary hormone release was evaluated. In normal women a dose-related decrease in Prl levels was observed, while in men the Prl decrement was not related to the dose employed. In women an increase in serum hGH occurred after administration of the lowest (40 mg) dose of piribedil. In normal men, on the contrary, a modest hGH stimulation was present after administration of all doses of the drug. No consistent changes in serum TSH, LH and FSH concentrations were observed and no side effects were reported. The results from this study indicate that piribedil can exert differential effects on hypophyseal trophic hormone release and that these effects are sex-related. It is possible that the differences observed in men and women after the administration of piribedil are due to a different endogenous dopaminergic tone, induced by the different sexual steroid environment.
Ganglioside treatment was evaluated with a multicenter, randomized, double-blind, controlled, cross-over vs placebo trial in 140 insulin-treated diabetic subjects with peripheral neuropathy. The ...patients entered the study when they showed an impairment in at least two of the electroneurographic parameters, and were assigned to two protocols according to the presence and severity of their neurological symptoms. Ninety-seven diabetic subjects with no or mild symptoms were assigned to protocol I, whereas 43 symptomatic patients were assigned to protocol II. the treatment periods lasted 6 weeks with an intermediate washout period of 4 weeks. The treatment consisted in the daily i.m. administration of 20 mg gangliosides or of placebo. Electroneurographic parameters were recorded at the beginning and at the end of each treatment period, whereas clinical and metabolic data (mean daily plasma glucose, glycosuria and glycosylated hemoglobin) were evaluated every three weeks in protocol I and every two weeks in protocol II. No change in the metabolic parameters was observed throughout the trial period. However, the treatment induced a statistically significant improvement of paresthesias (protocol II) and of some electrophysiological parameters; in particular, ganglioside treatment improved MCV of peroneal nerve (p less than 0.03) in patients of protocol I, MCV o ulnar nerve (p less than 0.002) and SCV of median nerve (p less than 0.06) in patients of protocol II. Furthermore, 22 subjects of protocol II showed a 'drug preference' while 10 preferred placebo and 9 had no preference. In conclusion, ganglioside treatment seems to have a positive effect on diabetic peripheral neuropathy, improving both some symptoms and some electrophysiological parameters.
