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Background: The importance of measuring blood pressure before morning micturition and in the afternoon, while working, is yet to be established in relation to the accuracy of home blood pressure monitoring (HBPM). Objective: To compare two HBPM protocols, considering 24-hour ambulatory blood pressure monitoring (wakefulness ABPM) as gold-standard and measurements taken before morning micturition (BM) and in the afternoon (AM), for the best diagnosis of systemic arterial hypertension (SAH), and their association with prognostic markers. Methods: After undergoing 24-hour wakefulness ABPM, 158 participants (84 women) were randomized for 3- or 5-day HBPM. Two variations of the 3-day protocol were considered: with measurements taken before morning micturition and in the afternoon (BM+AM); and with post-morning-micturition and evening measurements (PM+EM). All patients underwent echocardiography (for left ventricular hypertrophy - LVH) and urinary albumin measurement (for microalbuminuria - MAU). Result: Kappa statistic for the diagnosis of SAH between wakefulness-ABPM and standard 3-day HBPM, 3-day HBPM (BM+AM) and (PM+EM), and 5-day HBPM were 0.660, 0.638, 0.348 and 0.387, respectively. The values of sensitivity of (BM+AM) versus (PM+EM) were 82.6% × 71%, respectively, and of specificity, 84.8% × 74%, respectively. The positive and negative predictive values were 69.1% × 40% and 92.2% × 91.2%, respectively. The comparisons of intraclass correlations for the diagnosis of LVH and MAU between (BM+AM) and (PM+EM) were 0.782 × 0.474 and 0.511 × 0.276, respectively. Conclusions: The 3 day-HBPM protocol including measurements taken before morning micturition and during work in the afternoon showed the best agreement with SAH diagnosis and the best association with prognostic markers.

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Background: Pazopanib (PZP) may induce prolonged cardiac repolarization and proarrhythmic effects, similarly to other tyrosine kinase inhibitors. Objectives: To demonstrate PZP-induced prolonged cardiac repolarization and proarrhythmic electrophysiological effects and to investigate possible preventive effects of metoprolol and diltiazem on ECG changes (prolonged QT) in an experimental rat model. Methods: Twenty-four Sprague-Dawley adult male rats were randomly assigned to 4 groups (n = 6). The first group (normal group) received 4 mL of tap water and the other groups received 100 mg/kg of PZP (Votrient® tablet) perorally, via orogastric tubes. After 3 hours, the following solutions were intraperitoneally administered to the animals: physiological saline solution (SP), to the normal group and to the second group (control-PZP+SP group); 1 mg/kg metoprolol (Beloc, Ampule, AstraZeneca), to the third group (PZP+metoprolol group); and 1mg/kg diltiazem (Diltiazem, Mustafa Nevzat), to the fourth group (PZP+diltiazem group). One hour after, and under anesthesia, QTc was calculated by recording ECG on lead I. Results: The mean QTc interval values were as follows: normal group, 99.93 ± 3.62 ms; control-PZP+SP group, 131.23 ± 12.21 ms; PZP+metoprolol group, 89.36 ± 3.61 ms; and PZP+diltiazem group, 88.86 ± 4.04 ms. Both PZP+metoprolol and PZP+diltiazem groups had significantly shorter QTc intervals compared to the control-PZP+SP group (p < 0.001). Conclusion: Both metoprolol and diltiazem prevented PZP-induced QT interval prolongation. These drugs may provide a promising prophylactic strategy for the prolonged QTc interval associated with tyrosine kinase inhibitor use.

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Background:Ventricular and supraventricular premature complexes (PC) are frequent and usually symptomatic. According to a previous study, magnesium pidolate (MgP) administration to symptomatic patients can improve the PC density and symptoms.Objective:To assess the late follow-up of that clinical intervention in patients treated with MgP or placebo.Methods:In the first phase of the study, 90 symptomatic and consecutive patients with PC were randomized (double-blind) to receive either MgP or placebo for 30 days. Monthly follow-up visits were conducted for 15 months to assess symptoms and control electrolytes. 24-hour Holter was performed twice, regardless of symptoms, or whenever symptoms were present. In the second phase of the study, relapsing patients, who had received MgP or placebo (crossing-over) in the first phase, were treated with MgP according to the same protocol.Results:Of the 45 patients initially treated with MgP, 17 (37.8%) relapsed during the 15-month follow-up, and the relapse time varied. Relapsing patients treated again had a statistically significant reduction in the PC density of 138.25/hour (p < 0.001). The crossing-over patients reduced it by 247/hour (p < 0.001). Patients who did not relapse, had a low PC frequency (3 PC/hour). Retreated patients had a 76.5% improvement in symptom, and crossing-over patients, 71.4%.Conclusion:Some patients on MgP had relapse of symptoms and PC, indicating that MgP is neither a definitive nor a curative treatment for late follow-up. However, improvement in the PC frequency and symptoms was observed in the second phase of treatment, similar to the response in the first phase of treatment.

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Background: Studies have shown sodium restriction to have a beneficial effect on blood pressure (BP) of hypertensive patients. Objective: To evaluate the impact of light salt substitution for regular salt on BP of hypertensive patients. Methods: Uncontrolled hypertensive patients of both sexes, 20 to 65 years-old, on stable doses of antihypertensive drugs were randomized into Intervention Group (IG - receiving light salt) and Control Group (CG - receiving regular salt). Systolic BP (SBP) and diastolic BP (DBP) were analyzed by using casual BP measurements and Home Blood Pressure Monitoring (HBPM), and sodium and potassium excretion was assessed on 24-hour urine samples. The patients received 3 g of salt for daily consumption for 4 weeks. Results: The study evaluated 35 patients (65.7% women), 19 allocated to the IG and 16 to the CG. The mean age was 55.5 ± 7.4 years. Most participants had completed the Brazilian middle school (up to the 8th grade; n = 28; 80.0%), had a family income of up to US$ 600 (n = 17; 48.6%) and practiced regular physical activity (n = 19; 54.3%). Two patients (5.7%) were smokers and 40.0% consumed alcohol regularly (n = 14). The IG showed a significant reduction in both SBP and DBP on the casual measurements and HBPM (p < 0.05) and in sodium excretion (p = 0.016). The CG showed a significant reduction only in casual SBP (p = 0.032). Conclusions: The light salt substitution for regular salt significantly reduced BP of hypertensive patients.

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Background: Sudden cardiac death (SCD) is a sudden unexpected event, from a cardiac cause, that occurs in less than one hour after the symptoms onset, in a person without any previous condition that would seem fatal or who was seen without any symptoms 24 hours before found dead. Although it is a relatively frequent event, there are only few reliable data in underdeveloped countries. Objective: We aimed to describe the features of SCD in Ribeirão Preto, Brazil (600,000 residents) according to Coroners’ Office autopsy reports. Methods: We retrospectively reviewed 4501 autopsy reports between 2006 and 2010, to identify cases of SCD. Specific cause of death as well as demographic information, date, location and time of the event, comorbidities and whether cardiopulmonary resuscitation (CPR) was attempted were collected. Results: We identified 899 cases of SCD (20%); the rate was 30/100000 residents per year. The vast majority of cases of SCD involved a coronary artery disease (CAD) (64%) and occurred in men (67%), between the 6th and the 7th decades of life. Most events occurred during the morning in the home setting (53.3%) and CPR was attempted in almost half of victims (49.7%). The most prevalent comorbidity was systemic hypertension (57.3%). Chagas’ disease was present in 49 cases (5.5%). Conclusion: The majority of victims of SCD were men, in their sixties and seventies and the main cause of death was CAD. Chagas’ disease, an important public health problem in Latin America, was found in about 5.5% of the cases.

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Background: Stress is associated with cardiovascular diseases. Objective: This study aimed at assessing whether chronic stress induces vascular alterations, and whether these modulations are nitric oxide (NO) and Ca2+ dependent. Methods: Wistar rats, 30 days of age, were separated into 2 groups: control (C) and Stress (St). Chronic stress consisted of immobilization for 1 hour/day, 5 days/week, 15 weeks. Systolic blood pressure was assessed. Vascular studies on aortic rings were performed. Concentration-effect curves were built for noradrenaline, in the presence of L-NAME or prazosin, acetylcholine, sodium nitroprusside and KCl. In addition, Ca2+ flux was also evaluated. Results: Chronic stress induced hypertension, decreased the vascular response to KCl and to noradrenaline, and increased the vascular response to acetylcholine. L-NAME blunted the difference observed in noradrenaline curves. Furthermore, contractile response to Ca2+ was decreased in the aorta of stressed rats. Conclusion: Our data suggest that the vascular response to chronic stress is an adaptation to its deleterious effects, such as hypertension. In addition, this adaptation is NO- and Ca2+-dependent. These data help to clarify the contribution of stress to cardiovascular abnormalities. However, further studies are necessary to better elucidate the mechanisms involved in the cardiovascular dysfunction associated with stressors. (Arq Bras Cardiol. 2014; [online].ahead print, PP.0-0)

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Background:Autonomic dysfunction (AD) is highly prevalent in hemodialysis (HD) patients and has been implicated in their increased risk of cardiovascular mortality.Objective:To correlate heart rate variability (HRV) during exercise treadmill test (ETT) with the values obtained when measuring functional aerobic impairment (FAI) in HD patients and controls.Methods:Cross-sectional study involving HD patients and a control group. Clinical examination, blood sampling, transthoracic echocardiogram, 24-hour Holter, and ETT were performed. A symptom-limited ramp treadmill protocol with active recovery was employed. Heart rate variability was evaluated in time domain at exercise and recovery periods.Results:Forty-one HD patients and 41 controls concluded the study. HD patients had higher FAI and lower HRV than controls (p<0.001 for both). A correlation was found between exercise HRV (SDNN) and FAI in both groups. This association was independent of age, sex, smoking, body mass index, diabetes, and clonidine or beta-blocker use, but not of hemoglobin levels.Conclusion:No association was found between FAI and HRV on 24-hour Holter or at the recovery period of ETT. Of note, exercise HRV was inversely correlated with FAI in HD patients and controls. (Arq Bras Cardiol. 2015; [online]. ahead print, PP.0-0)

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Background:Familial amyloidotic polyneuropathy (FAP) is a rare disease diagnosed in Brazil and worldwide. The frequency of cardiovascular involvement in Brazilian FAP patients is unknown.Objective:Detect the frequency of cardiovascular involvement and correlate the cardiovascular findings with the modified polyneuropathy disability (PND) score.Methods:In a national reference center, 51 patients were evaluated with clinical examination, electrocardiography (ECG), echocardiography (ECHO), and 24-hour Holter. Patients were classified according to the modified PND score and divided into groups: PND 0, PND I, PND II, and PND > II (which included PND IIIa, IIIb, and IV). We chose the classification tree as the statistical method to analyze the association between findings in cardiac tests with the neurological classification (PND).Results:ECG abnormalities were present in almost 2/3 of the FAP patients, whereas ECHO abnormalities occurred in around 1/3 of them. All patients with abnormal ECHO also had abnormal ECG, but the opposite did not apply. The classification tree identified ECG and ECHO as relevant variables (p < 0.001 and p = 0.08, respectively). The probability of a patient to be allocated to the PND 0 group when having a normal ECG was over 80%. When both ECG and ECHO were abnormal, this probability was null.Conclusions:Brazilian patients with FAP have frequent ECG abnormalities. ECG is an appropriate test to discriminate asymptomatic carriers of the mutation from those who develop the disease, whereas ECHO contributes to this discrimination.

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Abstract Background: Studies suggest that statins have pleiotropic effects, such as reduction in blood pressure, and improvement in endothelial function and vascular stiffness. Objective: To analyze if prior statin use influences the effect of renin-angiotensin-aldosterone system inhibitors on blood pressure, endothelial function, and vascular stiffness. Methods: Patients with diabetes and hypertension with office systolic blood pressure ≥ 130 mmHg and/or diastolic blood pressure ≥ 80 mmHg had their antihypertensive medications replaced by amlodipine during 6 weeks. They were then randomized to either benazepril or losartan for 12 additional weeks while continuing on amlodipine. Blood pressure (assessed with ambulatory blood pressure monitoring), endothelial function (brachial artery flow-mediated dilation), and vascular stiffness (pulse wave velocity) were evaluated before and after the combined treatment. In this study, a post hoc analysis was performed to compare patients who were or were not on statins (SU and NSU groups, respectively). Results: The SU group presented a greater reduction in the 24-hour systolic blood pressure (from 134 to 122 mmHg, p = 0.007), and in the brachial artery flow-mediated dilation (from 6.5 to 10.9%, p = 0.003) when compared with the NSU group (from 137 to 128 mmHg, p = 0.362, and from 7.5 to 8.3%, p = 0.820). There was no statistically significant difference in pulse wave velocity (SU group: from 9.95 to 9.90 m/s, p = 0.650; NSU group: from 10.65 to 11.05 m/s, p = 0.586). Conclusion: Combined use of statins, amlodipine, and renin-angiotensin-aldosterone system inhibitors improves the antihypertensive response and endothelial function in patients with hypertension and diabetes.

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Abstract Casual blood pressure measurements have been extensively questioned over the last five decades. A significant percentage of patients have different blood pressure readings when examined in the office or outside it. For this reason, a change in the paradigm of the best manner to assess blood pressure has been observed. The method that has been most widely used is the Ambulatory Blood Pressure Monitoring - ABPM. The method allows recording blood pressure measures in 24 hours and evaluating various parameters such as mean BP, pressure loads, areas under the curve, variations between daytime and nighttime, pulse pressure variability etc. Blood pressure measurements obtained by ABPM are better correlated, for example, with the risks of hypertension. The main indications for ABPM are: suspected white coat hypertension and masked hypertension, evaluation of the efficacy of the antihypertensive therapy in 24 hours, and evaluation of symptoms. There is increasing evidence that the use of ABPM has contributed to the assessment of blood pressure behaviors, establishment of diagnoses, prognosis and the efficacy of antihypertensive therapy. There is no doubt that the study of 24-hour blood pressure behavior and its variations by ABPM has brought more light and less darkness to the field, which justifies the title of this review.

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The rhythm of movements and feeding activity of juveniles of Loricariichthys anus (Valenciennes, 1840) in the Quadros lake, South Brazil, are investigated. Between October 1997 and August 1998, 236 specimens were captured during six bimonthly 24 hour gillnet surveys. Significantly elevated levels of movement and feeding activity during the day are registered. The patterns of movement and feeding activity displayed no significant difference, suggesting that high movement activity levels can be attributed to feeding activity. The mean of the intestinal quotient was 1,89, indicating omnivorous feeding habits.

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The predator-prey relationship of Palaemonetes argentinus Nobili, 1901 and Culex pipiens s.l. larvae was studied under laboratory conditions. The prawns were separated in two groups, isolated and grouped ones. Mosquitoe larvae were offered to prawns in two forms, limited and unlimited offer to both groups. In the first analysis, values of predation did not differ significantly between males and females of P. argentinus. Predation in 24 h was 14,9 ± 4,2 larvae/prawn. A reduction of predation was observed with unlimited offer for the same hour, during all the experiment. Predation with unlimited offer was higher on the first day than on the second, but returned to high values on the third day, for both groups. In the grouped experiment, predation with limited offer was total on the first days, decreasing to the last day. As a result, P. argentinus was considered an efficient predator of C. pipiens s.l. larvae under laboratory conditions.

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The thermal requirements of Palmistichus elaeisis Delvare & LaSalle, 1993 were determined by rearing this pupal parasitoid in the following lepidopteran hosts: Diatraea saccharalis (Fabricius, 1794) (Crambidae), Anticarsia gemmatalis (Hübner, 1818), Heliothis virescens (Fabricius, 1777), Spodoptera frugiperda (J.E. Smith, 1797) (Noctuidae) and Thyrinteina arnobia (Stoll, 1782) (Geometridae). The experiment was set in laboratory conditions (temperatures between 18ºC and 30ºC, RH=70 ± 10% and 14-hour photoperiod). The life cycle (egg-adult) ranged from 40.4 ± 0.63 days (18ºC, H. virescens) to 18.1 ± 0.13 days (28ºC, D. saccharalis). The thermal constant of the egg-adult period ranged from 353.1 (D. saccharalis) to 407.7 degree-days (S. frugiperda). The lowest thermal threshold ranged from 5.0ºC (A. gemmatalis) to 7.5ºC (D. saccharalis). At 30ºC, all prepupae died. These results suggest that P. elaeisis can be reared in laboratory on all the hosts tested.

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The taxonomic composition, observed and estimated species richness, and patterns of community structure of arboreal spider assemblages in eleven sites surrounding the "Banhado Grande" wet plain in the state of Rio Grande do Sul, Brazil, are presented. These sites represent three different vegetational types: hillside (four sites), riparian (five sites) and flooded forests (two sites). The spiders were captured by beating on foliage and "aerial litter". A sample was defined as the result of beating on twenty bushes, tree branches or "aerial litter" clusters, which roughly corresponds to one-hour search effort per sample. Fifty five samples (five per site) were obtained, resulting in an observed richness of 212 species present as adult or identifiable juveniles. The total richness for all samples was estimated to be between 250 (Bootstrap) to 354 species (Jackknife 2). Confidence intervals of both sample and individual-based rarefaction curves for each vegetation type clearly indicated that flooded forest is the poorest vegetation type with respect to spider species richness, with hillside and riparian forests having a similar number of species. The percentage complementarity between the eleven sites indicated that all sites contain a distinct set of species, irrespective of their vegetation types. Nevertheless, the spider assemblages in riparian and hillside forests are more similar with respect to each other than when compared to flooded forest. Both cluster and nonmetric multidimensional scaling analyses showed no strong correspondence between the spider arboreal fauna and the three vegetation types. Moreover, a Mantel test revealed no significant association between species composition and geographic distance among sites.

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The only breeding record of Spartonoica maluroides (d'Orbigny & Lafresnaye, 1837) for Brazil is based on the observation of a fledgling in southern Rio Grande do Sul in January 1976. On 7 December 2005 we discovered a nest containing three nestlings at the southeastern end of Lagoa Pequena, municipality of Pelotas, Rio Grande do Sul. The nest was concealed at the base of a cavity in a Spartina densiflora (Poaceae) tussock located at the edge of a saltmarsh. The nest was built of fine pieces of dead Scirpus olneyi (Cyperaceae) and S. densiflora leaves firmly interlaced to the internal leaves of the tussock. Live leaves of S. densiflora lining the cavity comprised a substantial part of the nest's architecture, forming most of its upper lateral walls and roof. The lower section was more elaborate, resembling a deep cup and forming a distinct incubation chamber. Adults reached the nest's interior through an irregular apical opening amidst the leaves. The nest was 244 mm high and 140 mm wide. The incubation chamber had an external diameter of 138.5 mm, an internal diameter of 79.4 mm and was 86 mm deep. It was lined with fine leaves and white plant fibers. Nestlings were five to six days old. A total of 107 neossoptiles restricted to the capital, spinal and alar tracts were recorded in one nestling. The distribution of neossoptiles in the ocular region of S. maluroides forms a distinct pattern which can be typical of Furnariidae and related families. Two adults attended the nest, bringing small insects to the nestlings and removing fecal sacs. We recorded at least 74 visits to the nest during a ca. 6 h period during an afternoon. The average number of visits per hour was 12.8 ± 1.3. An adult bird spent on average 0.7 ± 0.56 minutes inside the nest attending nestlings. The nest remained unattended on average for 3.61 ± 3.13 minutes. The hour of the day had no influence on the amount of time spent by an adult in the nest or away from it. We returned to the area on 15 December 2005 and found the nest abandoned. Observations confirm that S. maluroides is a resident breeder in southern Brazil and that the saltmarshes of the Lagoa do Patos estuary are an important year-round habitat for the species. A nestling and the nest were collected to document the record.