Abnormal neurovascular control during exercise is linked to heart failure severity.

The purpose of this study was to determine if abnormalities of sympathetic neural and vascular control are present in mild and/or severe heart failure (HF) and to determine the underlying afferent mechanisms. Patients with severe HF, mild HF, and age-matched controls were studied. Muscle sympathetic nerve activity (MSNA) and forearm vascular resistance (FVR) in the nonexercising arm were measured during mild and moderate static handgrip. MSNA during moderate handgrip was higher at baseline and throughout exercise in severe HF vs. mild HF (peak MSNA 67 +/- 3 vs. 54 +/- 3 bursts/min, P < 0.0001) and higher in mild HF vs. controls (33 +/- 3 bursts/min, P < 0.0001), but the change in MSNA was not different between the groups. The change in FVR was not significantly different between the three groups during static exercise. During isolation of muscle metaboreceptors, MSNA and blood pressure remained elevated in normal controls and mild HF but not in severe HF. During mild handgrip, the increase in MSNA was exaggerated in severe HF vs. controls and mild HF, in whom MSNA did not increase. In summary, the increase in MSNA during static exercise in severe HF appears to be attributable to exaggerated central command or muscle mechanoreceptor control, not muscle metaboreceptor control.

["ARCHIDIA": a system for patients' data collection and computerized filing. Part I. Methodology]. / Sistema di raccolta dati paziente e archiviazione computerizzata "ARCHIDIA". Parte I--Metodologia.

This report describes a computer based program of patient clinical data collection: the ARCHIDIA system. The project relies on descriptive analysis of clinical events according to well defined methodological criteria. This allows the formulation of a concise diagnosis which is, at the same time, exhaustive of all essential information. Two are the basis principles of this methodology: To define, as accurately as possible, the logical steps necessary to elaborate the diagnosis, that is construed by a sequence of codes. To define all the conditions that must be followed so to use any code in a controlled and independent way. These criteria were derived from literature. The major claim of the system is likely to be the introduction of a "common language" between different ICUs. Uniformed diagnostic and clinical criteria are the main source of large data collection for descriptive, analytic and prospective studies. After a one year pilot study performed by 4 ICUs, ARCHIDIA was used, in 1991, by 20 centers from the area of Milan, Pavia, Como, Varese (70% of total) and 4148 patient data were collected. A descriptive analysis will be reported in the following paper.

["ARCHIDIA": a system for patients' data collection and computerized filing. Part II. General description of a caseload]. / Sistema di raccolta dati paziente e archiviazione computerizzata "ARCHIDIA". Parte II--Descrizione generale della casistica.

OBJECTIVE: To describe a population of patients admitted in ICU in an homogeneous urban area by means of a computed system. EXPERIMENTAL DESIGN: Observational study. SETTING: 20 general intensive care units of general and university hospitals. PATIENTS: Patients admitted in ICU from 1-1-1991 to 31-12-1991. 3 centers collected patients only for 6 months, starting on 1-6-1991. MEASUREMENTS: For each patient demographic data, hospitalization data, outcome, diagnosis and diagnostic procedures used during hospitalization according to defined criteria previously described, were collected. Data have been collected on PC using dedicated software. RESULTS: All centers concluded data collection, none abandoned the study. General characteristics of 4148 valuable patients were reported. Age was 52.9 years, SAPS 12.4 and mortality 21.7%. The patients spent 8.7 days in ICU and, when transferred to a general ward, the following hospitalization was 21.5 days. CONCLUSIONS: Data collection demonstrated the project feasibility. It realizes a continue up to date system inside each unit and allows the use of a "common language" and homogeneous methodology between centers.