The emergence of Staphylococcus aureus as the primary cause of cardiac device-related infective endocarditis.

BACKGROUND: Increasing use of cardiovascular implantable electronic devices (CIED), as permanent pacemakers (PPM), implantable cardioverter defibrillators (ICD), or cardiac resynchronization therapy (CRT), is associated with the emergence of CIED-related infective endocarditis (CIED-IE). We aimed to characterize CIED-IE profile, temporal trends, and prognostic factors. METHODS: CIED-IE diagnosed at Rennes University Hospital during years 1992-2017 were identified through computerized database, and included if they presented all of the following: (1) clinical signs of infection; (2) microbiological documentation through blood and/or CIED lead cultures; (3) lead or valve vegetation, or definite IE according to Duke criteria. Data were retrospectively extracted from medical charts. The cohort was categorized in three periods: 1992-1999, 2000-2008, and 2009-2017. RESULTS: We included 199 patients (51 women, 148 men, median age 73 years [interquartile range, 64-79]), with CIED-IE: 158 PPMs (79%), 24 ICD (12%), and 17 CRT (9%). Main pathogens were coagulase-negative staphylococci (CoNS: n = 86, 43%), Staphylococcus aureus (n = 60, 30%), and other Gram-positive cocci (n = 28, 14%). Temporal trends were remarkable for the decline in CoNS (P = 0.002), and the emergence of S. aureus as the primary cause of CIED-IE (24/63 in 2009-2017, 38%). Factors independently associated with one-year mortality were chronic obstructive pulmonary disease (COPD: hazard ratio 3.84 [1.03-6.02], P = 0.03), left-sided endocarditis (HR 2.25 [1.09-4.65], P = 0.03), pathogens other than CoNS (HR 3.16 [1.19-8.39], P = 0.02), and CIED removal/reimplantation (HR 0.41 [0.20-0.83], P = 0.01). CONCLUSIONS: S. aureus has emerged as the primary cause of CIED-IE. Left-sided endocarditis, COPD, pathogens other than CoNS, and no CIED removal/reimplantation are independent risk factors for one-year mortality.

Importance of ventricular longitudinal function in chronic heart failure.

AIMS: Despite its immediate relevance, cardiopulmonary exercise testing (CPET) is infrequently performed in the presence of chronic heart failure (CHF). Previous studies of patients suffering from CHF have found a closer correlation between exercise capacity and measurements of diastolic than systolic ventricularfunction. We examined the correlation between echocardiographic measurements and (i) results of CPET and (ii) cardiovascular prognosis. METHODS AND RESULTS: We performed resting two-dimensional echocardiograms and CPET in 140 patients with CHF (mean age = 61 ± 13 years, 111 men). The underlying heart disease was ischaemic in 48 patients (34%). They were followed for a mean of 38 months (range 28-52). The mean left ventricular (LV) ejection fraction (EF) was 30 ± 9% and peak VO2 17.2 ± 6.5 mL/kg/min. LVEF correlated weakly with peak VO2 (r = 0.21), while systolic and early diastolic LV longitudinal function correlated best [early diastolic peak velocity at the mitral annulus (E'): r = 0.38; global longitudinal strain (GLS): r = -0.4; P <0.001 for both]. By multiple variable regression analysis, the best prediction of peak VO2 was derived from a model based on age, mitral annulus end-diastolic peak velocity (A'), GLS, right ventricular (RV) systolic strain, and left atrial systolic strain (r² = 0.57; P <0.0001). The two best independent predictors of adverse cardiovascular events at 28 months were GLS (odds ratio 1.31, P <0.001; prognostic cut-off = -8%) and RV systolicstrain (odds ratio 1.05, P =0.01; prognostic cut-off = -22%). CONCLUSION: Resting RV and LV longitudinal functions were reliable predictors of adverse cardiovascular events and correlated moderately with, but not took to the place of, CPET measurements.