Sudden death circadian rhythm in Chagasic patients compared to non-Chagasic patients.

Unlabelled: Chagas disease (Ch) affects 8-10 million people in Latin America, most of them are poor. Sudden death (SD) is the major cause of death in patients with Ch. To the best of our knowledge, the present report covers the largest reported series comparing the SD of Ch versus non-Ch patients Objective: To compare the circadian rhythm of SD in Ch versus non-Ch patients.

Time-weighted vs. conventional quantification of 24-h average systolic and diastolic ambulatory blood pressures.

Background: Conventional calculation of mean 24-h ambulatory blood pressure (BP), SBP and DBP based on the average of all BP readings disregards the fact that a larger number of measurements is usually scheduled during the daytime than at night, an imbalance possibly leading to an overestimation of 24-h average BP. The aim of our study was to quantify this possible bias and to explore its determinants.

Methods: Four hundred and fifty untreated individuals were subdivided into three groups (150 individuals each) with three different ambulatory blood pressure measurement schedules for day/night: group I, four (day)/two (night) readings/h; group II, four (day)/three (night) readings/h; and group III, with BP readings every 30 min throughout 24 h.

[Circadian profiles of heart rate and its instantaneous variability in patients with chronic Chagas' disease].

Introduction And Objectives: Impairment of the autonomous nervous system in early stages of Chagas' disease is still a matter of debate, although multiple approaches (including heart rate response to orthostatism and the Valsalva maneuver, and spontaneous variability) have been used to ascertain its occurrence. The circadian profile of heart rate and its variability have not been investigated in patients with Chagas' disease.

Patients And Method: We analyzed the 24-hour heart rate by Holter recordings in 63 patients with and without ECG alterations, who had positive serological findings for Chagas' disease.

Chronic inappropriate sinus tachycardia in elderly females.

Background: The vast majority of reports of inappropriate sinus tachycardia (IST) had included predominantly young females with ages ranging between 15 and 46 years. In contrast, the present study presents the findings in four elderly females (aged 61-71 years) with long-standing symptoms of palpitations, more than 15 years, in whom IST was diagnosed in their 6th or 7th decade.

Methods: Clinical and laboratory examinations including electrocardiograms, echocardiograms, and heart rate variability studies were retrospectively reviewed in four of the nine elderly female patients with long-standing cardiac symptoms.