196 research outputs found
3
The aim of this study was the assessment of the Regional Myocardial Work (RMW) by measuring the stress-strain relationships in the left myocardium, under basic and ischemic conditions. In 11 swines, 4 Sonometrics crystals were placed in the region perfused by the left anterior descending artery (LAD) circumscribing a tetrahedral myocardial volume (TMV). The 1st crystal was situated 45mm below the pulmonary artery, beside the LAD. Under control of the acquisition device, the 2nd was placed 10mm below the 1st following the LAD, the 3rd 10mm at the left side of the 1st and the 4th in equidistant point between the 1st and the 2nd, 5mm deep within the myocardium. A Millar, omnidirectional pressure catheter was placed within the TMV. The 6 distances and intramyocardial pressure measured were digitized and mathematically synthesized. The variation in TMV strain (µv) and stress (µp) was calculated throughout the cardiac cycle, resulting in 2 equations. The relationships between µp and µv result in a stress-strain loop, from which RMW was calculated. Simultaneously, Pulsed Doppler Tissue Imaging (DTI) assessed systolic (VS), early-diastolic (VE) and latediastolic (VA) myocardial velocities. Measurements were performed under basic (B), during ischemia by occlusion LDA for 40 seconds, after 1 and 15 minutes of reperfusion (Occlusion (O), Reperfusion1 (R1) and 2 (R2) periods). The average of RMW, under basic conditions, wa
Symptomatic and Asymptomatic Neurological Complications of Infective Endocarditis: Impact on Surgical Management and Prognosis
International audienceObjectives:Symptomatic neurological complications (NC) are a major cause of mortality in infective endocarditis (IE) but the impact of asymptomatic complications is unknown. We aimed to assess the impact of asymptomatic NC (AsNC) on the management and prognosis of IE.Methods: From the database of cases collected for a population-based study on IE, we selected 283 patients with definite left-sided IE who had undergone at least one neuroimaging procedure (cerebral CT scan and/or MRI) performed as part of initial evaluation.Results Among those 283 patients, 100 had symptomatic neurological complications (SNC) prior to the investigation, 35 had an asymptomatic neurological complications (AsNC), and 148 had a normal cerebral imaging (NoNC). The rate of valve surgery was 43% in the 100 patients with SNC, 77% in the 35 with AsNC, and 54% in the 148 with NoNC (p<0.001). In-hospital mortality was 42% in patients with SNC, 8.6% in patients with AsNC, and 16.9% in patients with NoNC (p<0.001). Among the 135 patients with NC, 95 had an indication for valve surgery (71%), which was performed in 70 of them (mortality 20%) and not performed in 25 (mortality 68%). In a multivariate adjusted analysis of the 135 patients with NC, age, renal failure, septic shock, and IE caused by S. aureus were independently associated with in-hospital and 1-year mortality. In addition SNC was an independent predictor of 1-year mortality.Conclusions The presence of NC was associated with a poorer prognosis when symptomatic. Patients with AsNC had the highest rate of valve surgery and the lowest mortality rate, which suggests a protective role of surgery guided by systematic neuroimaging results
The Gene Expression Analysis of Blood Reveals S100A11 and AQP9 as Potential Biomarkers of Infective Endocarditis
BACKGROUND: The diagnostic and prognostic assessments of infective endocarditis (IE) are challenging. To investigate the host response during IE and to identify potential biomarkers, we determined the circulating gene expression profile using whole genome microarray analysis. METHODS AND RESULTS: A transcriptomic case-control study was performed on blood samples from patients with native valve IE (n = 39), excluded IE after an initial suspicion (n = 10) at patient's admission, and age-matched healthy controls (n = 10). Whole genome microarray analysis showed that patients with IE exhibited a specific transcriptional program with a predominance of gene categories associated with cell activation as well as innate immune and inflammatory responses. Quantitative real-time RT-PCR performed on a selection of highly modulated genes showed that the expression of the gene encoding S100 calcium binding protein A11 (S100A11) was significantly increased in patients with IE in comparison with controls (P<0.001) and patients with excluded IE (P<0.05). Interestingly, the upregulated expression of the S100A11 gene was more pronounced in staphylococcal IE than in streptococcal IE (P<0.01). These results were confirmed by serum concentrations of the S100A11 protein. Finally, we showed that in patients with IE, the upregulation of the aquaporin-9 gene (AQP9) was significantly associated with the occurrence of acute heart failure (P = 0.02). CONCLUSIONS: Using transcriptional signatures of blood samples, we identified S100A11 as a potential diagnostic marker of IE, and AQP9 as a potential prognostic factor
Distinct cardioprotective mechanisms of immediate, early and delayed ischaemic postconditioning
Cardioprotection against ischaemia/reperfusion injury in mice can be achieved by delayed ischaemic postconditioning (IPost) applied as late as 30 min after the onset of reperfusion. We determined the efficacy of delayed IPost in a rat model of myocardial infarction (MI) and investigated potential underlying mechanisms of this phenomenon. Rats were subjected to 20, 30 or 45 min of coronary artery occlusion followed by 120 min of reperfusion (I/R). Immediate and early IPost included six cycles of I/R (10/10 s) applied 10 s or 10 min after reperfusion onset. In the second series of experiments, the rats were subjected to 30 min of coronary occlusion followed by IPost applied 10 s, 10, 30, 45 or 60 min after the onset of reperfusion. Immediate and early IPost (applied 10 s or 10 min of reperfusion) established cardioprotection only when applied after a period of myocardial ischaemia lasting 30 min. Delayed IPost applied after 30 or 45 min of reperfusion reduced infarct sizes by 36 and 41 %, respectively (both P < 0.01). IPost applied 60 min after reperfusion onset was ineffective. Inhibition of RISK pathway (administration of ERK1/2 inhibitor PD-98059 or PI3K inhibitor LY-294002) abolished cardioprotection established by immediate IPost but had no effect on cardioprotection conferred by early IPost. Blockade of SAFE pathway using JAK/STAT inhibitor AG490 had no effect on the immediate or early IPost cardioprotection. Blockade of mitochondrial KATP (mitoKATP) channels (with 5-Hydroxydecanoate) abolished cardioprotection achieved by immediate and early IPost, but had no effect on cardioprotection when IPost was applied 30 or 45 min into the reperfusion period. Immediate IPost increased phosphorylation of PI3K-AKT and ERK1/2. Early or delayed IPost had no effect on phosphorylation of PI3K-AKT, ERK1/2 or STAT3. These data show that in the rat model, delayed IPost confers significant cardioprotection even if applied 45 min after onset of reperfusion. Cardioprotection induced by immediate and early postconditioning involves recruitment of RISK pathway and/or mitoKATP channels, while delayed postconditioning appears to rely on a different mechanism
Prognostic factors in left-sided endocarditis: results from the andalusian multicenter cohort
<p>Abstract</p> <p>Background</p> <p>Despite medical advances, mortality in infective endocarditis (IE) is still very high. Previous studies on prognosis in IE have observed conflicting results. The aim of this study was to identify predictors of in-hospital mortality in a large multicenter cohort of left-sided IE.</p> <p>Methods</p> <p>An observational multicenter study was conducted from January 1984 to December 2006 in seven hospitals in Andalusia, Spain. Seven hundred and five left-side IE patients were included. The main outcome measure was in-hospital mortality. Several prognostic factors were analysed by univariate tests and then by multilogistic regression model.</p> <p>Results</p> <p>The overall mortality was 29.5% (25.5% from 1984 to 1995 and 31.9% from 1996 to 2006; Odds Ratio 1.25; 95% Confidence Interval: 0.97-1.60; p = 0.07). In univariate analysis, age, comorbidity, especially chronic liver disease, prosthetic valve, virulent microorganism such as <it>Staphylococcus aureus</it>, <it>Streptococcus agalactiae </it>and fungi, and complications (septic shock, severe heart failure, renal insufficiency, neurologic manifestations and perivalvular extension) were related with higher mortality. Independent factors for mortality in multivariate analysis were: Charlson comorbidity score (OR: 1.2; 95% CI: 1.1-1.3), prosthetic endocarditis (OR: 1.9; CI: 1.2-3.1), <it>Staphylococcus aureus </it>aetiology (OR: 2.1; CI: 1.3-3.5), severe heart failure (OR: 5.4; CI: 3.3-8.8), neurologic manifestations (OR: 1.9; CI: 1.2-2.9), septic shock (OR: 4.2; CI: 2.3-7.7), perivalvular extension (OR: 2.4; CI: 1.3-4.5) and acute renal failure (OR: 1.69; CI: 1.0-2.6). Conversely, <it>Streptococcus viridans </it>group etiology (OR: 0.4; CI: 0.2-0.7) and surgical treatment (OR: 0.5; CI: 0.3-0.8) were protective factors.</p> <p>Conclusions</p> <p>Several characteristics of left-sided endocarditis enable selection of a patient group at higher risk of mortality. This group may benefit from more specialised attention in referral centers and should help to identify those patients who might benefit from more aggressive diagnostic and/or therapeutic procedures.</p
Electrocardiographic features of immune checkpoint inhibitor associated myocarditis
Background Myocarditis is a highly morbid complication of immune checkpoint inhibitor (ICI) use that remains inadequately characterized. The QRS duration and the QTc interval are standardized electrocardiographic measures that are prolonged in other cardiac conditions; however, there are no data on their utility in ICI myocarditis. Methods From an international registry, ECG parameters were compared between 140 myocarditis cases and 179 controls across multiple time points (pre-ICI, on ICI prior to myocarditis, and at the time of myocarditis). The association between ECG values and major adverse cardiac events (MACE) was also tested. Results Both the QRS duration and QTc interval were similar between cases and controls prior to myocarditis. When compared with controls on an ICI (93±19 ms) or to baseline prior to myocarditis (97±19 ms), the QRS duration prolonged with myocarditis (110±22 ms, p<0.001 and p=0.009, respectively). In contrast, the QTc interval at the time of myocarditis (435±39 ms) was not increased compared with pre-myocarditis baseline (422±27 ms, p=0.42). A prolonged QRS duration conferred an increased risk of subsequent MACE (HR 3.28, 95% CI 1.98 to 5.62, p<0.001). After adjustment, each 10 ms increase in the QRS duration conferred a 1.3-fold increase in the odds of MACE (95% CI 1.07 to 1.61, p=0.011). Conversely, there was no association between the QTc interval and MACE among men (HR 1.33, 95% CI 0.70 to 2.53, p=0.38) or women (HR 1.48, 95% CI 0.61 to 3.58, p=0.39). Conclusions The QRS duration is increased in ICI myocarditis and is associated with increased MACE risk. Use of this widely available ECG parameter may aid in ICI myocarditis diagnosis and risk-stratification
- …