Aim: The study was designed to evaluate the prognostic value of the 6-min walk test (6MWT) in patients with mild to moderate congestive heart failure (CHF). Methods and results: Two hundred and fourteen patients (119 men and 95 women, mean age 64 years) were followed for a mean period of 34 months to assess event-free survival (death, heart transplantation). Sixty-six patients (34%) died (63 cardiovascular causes, 2 cancer and 1 stroke) and five patients underwent heart transplantation. For patients who walked -300 m during the 6MWT, survival was 62% compared with 82% in patients who walked 300-450 m or)450 m. With univariate analysis, NYHA class was the strongest predictor of death. LVEF (P-0.0001), aetiology of heart failure (P-0.001), LV filling pattern (Ps0.002) and 6MWT distance (P-0.01) were all significantly related to survival. No significant relationship was found between survival, peak oxygen consumption or anaerobic threshold. Multivariate analysis using the Cox-stepwise regression model showed that LV fractional shortening (P-0.009) and 6MWT distance (P-0.0005) were the strongest prognostic markers. Conclusion: A 6MWT distance of -300 m is a simple and useful prognostic marker of subsequent cardiac death in unselected patients with mild to moderate CHF.

Acquired metallo-␤-lactamases (MBLs) are resistance determinants of increasing clinical importance in Gram-negative bacterial pathogens, which confer a broad-spectrum ␤-lactam resistance, including carbapenems. Several such enzymes have been described since the 1990s. In the present study, a novel acquired MBL, named FIM-1, was identified and characterized. The bla FIM-1 gene was cloned from a multidrug-resistant Pseudomonas aeruginosa clinical isolate (FI-14/157) cultured from a patient with a vascular graft infection in Florence, Italy. The isolate belonged in the sequence type 235 epidemic clonal lineage. The FIM-1 enzyme is a member of subclass B1 and, among acquired MBLs, exhibited the highest similarity (ca. 40% amino acid identity) with NDM-type enzymes. In P. aeruginosa FI-14/157, the bla FIM-1 gene was apparently inserted into the chromosome and associated with ISCR19-like elements that were likely involved in the capture and mobilization of this MBL gene. Transfer experiments of the bla FIM-1 gene to an Escherichia coli strain or another P. aeruginosa strain by conjugation or electrotransformation were not successful. The FIM-1 protein was produced in E. coli and purified by two chromatography steps. Analysis of the kinetic parameters, carried out with the purified enzyme, revealed that FIM-1 has a broad substrate specificity, with a preference for penicillins (except the 6␣-methoxy derivative temocillin) and carbapenems. Aztreonam was not hydrolyzed. Detection of this novel type of acquired MBL in a P. aeruginosa clinical isolate underscores the increasing diversity of such enzymes that can be encountered in the clinical setting.A cquired metallo-␤-lactamases (MBLs) are resistance determinants of increasing clinical importance in Gram-negative bacterial pathogens, including Pseudomonas aeruginosa, Enterobacteriaceae, and other Gram-negative nonfermenters. These enzymes can degrade most ␤-lactams, including carbapenems, and escape inhibition by the conventional ␤-lactamase inhibitors or avibactam. Thus, they are able to confer an extended ␤-lactam resistance profile to the bacterial host that is not reversible by ␤-lactamase inhibitors (1).Acquired MBLs were detected since the early 1990s, the first representatives being IMP-and VIM-type enzymes (2-4). Thereafter, a number of additional lineages of acquired MBLs have been described, including the SPM-, GIM-, SIM-, KHM-, NDM-, AIM-, DIM-, SMB-, and TMB-type enzymes (5, 6; see also reference 1 and references therein). By convention, different MBL types diverge from each other at by least 30% at the amino acid sequence level (7). Enzymes of different types may differ in functional properties, and the corresponding genes may be associated with different types of mobile genetic elements responsible for their dissemination, such as mobile gene cassettes inserted into integrons, ISCR elements, or composite transposons (8, 9).We report here on the identification and characterization of a new type of acquired MBL, named FIM-1, in a multidrug-resistant clinical ...

Background: Stratification of the severity of heart failure has major prognostic and therapeutic implications. Aims: To Ž . prospectively compare different methods of assessment of functional capacity in patients with chronic heart failure CHF . Ž . Ž . Methods and results:We studied 143 patients 78 male and 65 female with CHF aged less than 70 years mean 57.3 years . Functional assessment was made clinically according to NYHA classification and according to the Goldman Activity Scale Ž . Ž . Classification GASC . Cardiovascular performance was measured by peak O consumption pVO and anaerobic threshold 2 2 Ž . Ž . AT at cardiopulmonary exercise test and by the distance walked during a 6-min walk test 6-MWT . Clinical scales resulted Ž significantly related. Peak VO and AT showed a mild relation with distance covered at 6-MWT r s 0.56 and r s 0.46, 2 . respectively . Concordance between NYHA classification and levels of performance at cardiopulmonary exercise test or at 6-MWT was less than 50%. Conclusion: Our results suggest that none of the usually employed methods give a definitive assessment of functional capacity of cardiovascular system and a high degree of discordance exists among the results of different tests in the same patient. Although NYHA classification maintains its value in clinical evaluation of patients with Ž . CHF, the 6-min walk test is recommended in patients with mild-to-moderate CHF II᎐III NYHA classes as a simple and useful screening test to select patients for further diagnostic evaluation. ᮊ

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Decreased sensitivity of cardiopulmonary and arterial baroreceptors has been hypothesized to sustain sympathetic activation in patients with heart failure. In the present investigation the relationship between the impairment of baroreflex sensitivity and clinical severity of congestive heart failure was investigated. The authors studied 58 patients with heart failure (14 in NYHA class I, 22 in NYHA class II, and 22 in NYHA class III), 38 women and 20 men, age range 28-65 years. Thirty-two patients suffered from idiopathic dilated cardiomyopathy and 26 from coronary heart disease. As control group they examined 21 age-matched subjects. Baroreceptor sensitivity was studied by using the Valsalva maneuver as stimulus. Arterial pressure and heart rate were measured noninvasively by Finapres instrument (Ohmeda) and signals were recorded and elaborated with a personal computer. A decrease of baroreflex sensitivity was already demonstrable in NYHA class I patients (4.72 +/- 3.31 vs 9.25 +/- 5.05 msec/mm Hg in control group) (p < 0.005). A further impairment of baroreceptor response was found in patients in NYHA class II (1.94 +/- 2.88 msec/mm Hg, p < 0.001) and class III (1.78 +/- 1.52 msec/mm Hg, p < 0.001). Baroreceptor response showed a significant correlation with functional NYHA class (r = 0.61, p < 0.001) and anaerobic threshold (r = 0.57, p < 0.001) while the correlation was less tight with left ventricular end-diastolic diameter, fractional shortening, left ventricular ejection fraction, pulmonary mean arterial blood pressure, cardiac index, distance at 6 minutes walk corridor test, and maximal oxygen consumption (VO2max). These results suggest that baroreceptor function may be impaired early in the clinical course of heart failure and may contribute to sympathetic activation.

To differentiate bacterial from viral infections the level of C-reactive protein in serum samples was studied in three groups of children under 5 years of age with gastroenteritis. Of the 53 children with bacterial infection, 41 (77%) had C-reactive protein levels > or = 12 mg1 -1, 32 (66%) > or = 20 mgl-1 and 24 (45%) > or = 35 mgl-1. Of the 35 patients with viral infection, 4 (11%) had C-reactive protein levels > or = 12 mgl-1, 3 (9%) > or = 20 mgl-1 and 1 (3%) > or = 35 mgl-1. The best balance between sensitivity and specificity of C-reactive protein was obtained for a cut-off level > or = 12 mgl-1 (sensitivity 77%, specificity 89%) as compared to > or = 20 mgl-1 (sensitivity 58%, specificity 97%) and > or = 35 mgl-1 (sensitivity 44%, specificity 97%). Our results suggest that the determination of C-reactive protein values may be a useful tool for predicting bacterial gastroenteritis in children.

Progressive systemic sclerosis (PSS) is characterized in its first phases by vascular damage. Lungs are involved in two thirds of patients with initial progressive destruction of the capillary bed and consequent reduction of the functional reserve, which may lead to hypertension of the pulmonary circulation. For these reasons it is of great interest to have early information about the pressure of the pulmonary circulation, both at rest and during exercise, to follow the progression and the evolution of the illness independently from subjective symptoms. The aim of the study was to evaluate by a noninvasive method, saline-enhanced Doppler echocardiography, the behavior of the right ventricular systolic pressure in patients with PSS, at rest and during exercise, without clear instrumental or clinical signs of pulmonary involvement at rest. Nine patients (7 women and 2 men) with PSS, aged 55.7 +/- 8.7 years, and 9 control subjects were evaluated. All patients had normal pulmonary pressure at rest and negative history for effort dyspnea. Subjects underwent Doppler echocardiographic examination at rest and during exercise. Right ventricular systolic pressure was evaluated by saline-enhanced Doppler technique, at rest and throughout exercise. At rest the right ventricular systolic pressure was normal in all patients and controls. At the end of exercise, in 4 patients, values were still normal (40.7 +/- 2.2 mmHg); in the others pathologic values were recorded (59.8 +/- 3.9 mmHg). In the control group values were always normal (35.6 +/- 4.6 mmHg). In our study the saline-enhanced Doppler echocardiography has been demonstrated to be an important diagnostic tool for the noninvasive evaluation of right ventricular systolic pressure, both at rest and during exercise; it could be useful in monitoring the pulmonary vascular damage in patients with PSS.