Utility and safety of coronary angiography in patients with acute infective endocarditis who required surgery.

OBJECTIVES: To assess the benefit/risk ratio to perform a coronary angiography (CA) before surgery for infective endocarditis (IE). METHODS: We conducted a single-center prospective registry including 272 patients with acute IE intended for surgery and compared patients who underwent a preoperative CA (n = 160) with those who did not (n = 112). A meta-analysis of 3 observational studies was also conducted and included 551 patients: 342 who underwent a CA and 209 who did not. RESULTS: In our registry, combined bypass surgery (CABG) was performed in 17% of the patients with preoperative CA. At 2 years, the rate of the primary composite end point (all-cause death, new systemic embolism, stroke, new hemodialysis) was similar in the CA (38%) and no-CA (37%) groups. In-hospital and 2-year individual end points were all similar between groups. There were only 2 episodes of systemic embolism after CA and only one possibly related to a vegetation dislodgement. In the meta-analysis, combined CABG was performed in 18% of the patients with preoperative CA. All-cause death was similar in both groups: odds ratio, 0.98 [0.62-1.53], P = .92. Only 5 cases of systemic embolism possibly related to a vegetation dislodgement were reported. New hemodialysis was numerically more frequent in the CA group: odds ratio, 1.68 [0.79-3.58] (18% vs 14%, P = .18). CONCLUSIONS: In daily practice, two-thirds of the patients with acute IE who required surgery have a preoperative CA leading to a combined CABG in 18% of the patients. Our results suggest that to perform a preoperative CA in this context is not associated with improved prognosis.

Dimensionless Index in Patients With Low-Gradient Severe Aortic Stenosis and Preserved Ejection Fraction.

Background Risk stratification of patients with low-gradient (LG) severe aortic stenosis (AS) despite preserved left ventricular ejection fraction remains challenging. We sought to evaluate the relationship between the dimensionless index (DI)-the ratio of the left ventricular outflow tract time-velocity integral to that of the aortic valve jet-and mortality in these patients. Methods Seven hundred fifty-five patients with LG severe AS (defined by aortic valve area ≤1 cm2 or aortic valve area indexed to body surface area ≤0.6 cm2/m2 and mean aortic pressure gradient <40 mm Hg) and preserved left ventricular ejection fraction ≥50% were studied. Flow status was defined according to stroke volume index <35 mL/m2 (low flow, LF) or ≥35 mL/m2 (normal flow, NF). Results After adjustment for age, sex, body mass index, Charlson comorbidity index, history of hypertension, history of atrial fibrillation, AS-related symptoms, left ventricular ejection fraction, indexed left ventricular ventricular mass, aortic valve area, and aortic valve replacement as a time-dependent covariate, patients with LG-LF and DI<0.25 exhibited a considerable increased risk of death compared with patients with LG-NF and DI≥0.25 (adjusted hazard ratio, 2.41 [95% CI, 1.61-3.62]; P<0.001), LG-NF and DI<0.25 (adjusted hazard ratio, 1.84 [95% CI, 1.24-2.73]; P=0.003), and LG-LF and D≥0.25 (adjusted hazard ratio, 2.27 [95% CI, 1.42-3.63]; P<0.001). In contrast, patients with LG-LF and DI≥0.25, LG-NF and DI<0.25, and LG-NF and DI≥0.25 had similar outcome. DI<0.25 showed incremental prognostic value in patients with LG-LF severe AS but not in patients with LG-NF severe AS. Conclusions Among patients with LG severe AS and preserved left ventricular ejection fraction, decreased DI<0.25 is a reliable parameter in patients with LF to identify a subgroup of patients at higher risk of death who may derive benefit from aortic valve replacement.

Loss of the mRNA-like region in mitochondrial tmRNAs of jakobids.

It has been postulated that a highly reduced form of transfer messenger RNA (tmRNA), a bacterial molecule involved in the rescue of stalled ribosomes during translation, is expressed in the mitochondrion of the jakobid Reclinomonas americana. Here we show that genes encoding both one-piece and two-piece tmRNAs are present in six different jakobid mitochondrial DNAs. Mitochondrial tmRNAs have retained the highly conserved tRNA(Ala)-like domain, but they apparently lack the mRNA-like region present in all bacterial tmRNAs. Comparative analysis of jakobid mitochondrial genomes shows that a potential mRNA-like region in R. americana (orf64) is located at distant genomic positions in other jakobids. Our results strongly suggest that orf64 is a tatA homolog. Through Northern hybridization we confirm the postulated reduced size of both a one-piece tmRNA in Jakoba libera and a two-piece tmRNA in Seculamonas ecuadoriensis. The J. libera tmRNA is post-transcriptionally modified by addition of a 3' CCA tail, processed in vitro by RNase P RNA, and specifically charged with alanine in vitro by alanyl-tRNA synthetase. Our results strongly support the functionality of these reduced mitochondrial tmRNAs.