Impact of selected comorbidities on the presentation and management of aortic stenosis

Background: Contemporary data regarding the impact of comorbidities on the clinical presentation and management of patients with severe aortic stenosis (AS) are scarce. Methods Prospective registry of severe patients with AS across 23 centres in nine European countries. Results Of the 2171 patients, chronic kidney disease (CKD 27.3%), left ventricular ejection fraction (LVEF) = 2 of these). The decision to perform aortic valve replacement (AVR) was taken in a comparable proportion (67%, 72% and 69%, in patients with 0, 1 and >= 2 comorbidities;p=0.186). However, the decision for TAVI was more common with more comorbidities (35.4%, 54.0% and 57.0% for no, 1 and >= 2;p= 2 comorbidities than in those without (8.7%, 10.0% and 15.7%;p= 2 comorbidities (30.8 days) than in those without (35.7 days;p=0.012). Patients with reduced LVEF tended to be offered an AVR more frequently and with a shorter delay while patients with CKD were less frequently treated. Conclusions: Comorbidities in severe patients with AS affect the presentation and management of patients with severe AS. TAVI was offered more often than SAVR and performed within a shorter time period

Evaluating the Association between Contrast Medium Dosage and Acute Kidney Injury in Transcatheter Aortic Valve Replacement Using Different Predictive Models

Recent studies have suggested that contrast medium (CM) volume is associated with acute kidney injury (AKI) after transcatheter aortic valve replacement (TAVR). However, in a high-risk elderly TAVR population, the prognostic value and ideal threshold of CM dosage for AKI is unclear. Data of 532 successive TAVR patients (age 81.1 ± 6.8 years, EuroSCORE II 4.8% ± 6.0%) were therefore retrospectively analyzed. Based on a recently published formula, the renal function (preprocedural serum creatinine: SCr) corrected ratio of CM and body weight (CM*SCr/BW) was calculated to determine the risk of postprocedural contrast-associated AKI. AKI occurred in 94 patients (18.3%) and significantly increased 1-year all-cause mortality (23.4% vs. 13.1%; p = 0.001). A significant correlation between AKI and 30-day as well as 1-year all-cause mortality was observed (p = 0.001; p = 0.007). However, no association between CM dosage or the CM*SCr/BW ratio with the occurrence of AKI was seen (p = 0.968; p = 0.442). In our all-comers, all-access cohort, we found no relationship between CM dosage, or the established risk ratio model and the occurrence of postprocedural AKI. Further research needs to be directed towards different pathophysiological causes and preventive measures as AKI impairs short- and long-term survival

Thalhammer F: Multiple-dose pharmacokinetics of linezolid during continuous venovenous haemofiltration

Objectives: Linezolid is a new antibacterial agent with a broad spectrum of activity against Gram-positive pathogens including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus spp., and penicillin-resistant Streptococcus pneumoniae. The aim of this prospective, single-centre, open-label, two-arm study was to investigate the pharmacokinetics of linezolid during continuous venovenous haemofiltration (CVVH) in critically ill patients and to derive a dosage recommendation. Patients and methods: Twenty anuric ICU patients undergoing CVVH (mean age and body weight 60.7 ± 10.9 years and 86.0 ± 18.0 kg) were included. All patients received linezolid 600 mg intravenously every 12 h. CVVH was performed using highly permeable polysulphone membranes (PSHF 1200, Baxter, Germany and AV 400, Fresenius, Germany). Mean blood flow rate and ultrafiltration rate were 186 ± 15 and 40 ± 8 mL/min, respectively. Post-dilution was performed. Results: The pharmacokinetics of linezolid in critically ill patients with acute renal failure undergoing CVVH were comparable to healthy subjects and patients without renal impairment. The elimination half-life, total clearance and haemofiltration clearance were 4.3 ± 1.7 h, 9.3 ± 3.5 L/h and 1.9 ± 0.8 L/h, respectively. Conclusions: Our results showed that linezolid was highly removable by CVVH. These data suggest that a schedule of 600 mg linezolid at least twice daily may also be an appropriate dosing for patients with severe Gram-positive infections undergoing CVVH with both types of membranes

Transcatheter aortic valve replacement (TAVR) leads to an increase in the subendocardial viability ratio assessed by pulse wave analysis.

BACKGROUND:Pulse wave analysis (PWA) is a useful tool for non-invasive assessment of central cardiac measures as subendocardial perfusion (Subendocardial Viability Ratio, SEVR) or contractility (dP/dtmax). The immediate influence of transcatheter aortic valve replacement (TAVR) on these indices has not been investigated yet. METHODS:We prospectively enrolled 40 patients presenting with severe aortic stenosis receiving TAVR. Central pressure curves were derived from radial and carotid sites using PWA up to 2 days before and 7 days after TAVR. Parameters were compared between peripheral measurement sites. Changes in SEVR, dP/dtmax and in indices of vascular stiffness were assessed. Additionally, association of these variables with clinical outcome was evaluated during a 12-month follow-up. RESULTS:Central waveform parameters were comparable between measurement sites. SEVR, but not dP/dtmax, augmentation Index (AIx) or augmentation pressure height (AGPH) correlated significantly with disease severity reflected by peak transvalvular velocity and mean transvalvular pressure gradient over the aortic valve (Vmax, ΔPm) [r = -0.372,p = 0.029 for Vmax and r = -0.371,p = 0.021 for ΔPm]. Vmax decreased from 4.5m/s (IQR:4.1-5.0) to 2.2m/s (IQR:1.9-2.7), (p<0.001). This resulted in a significant increase in SEVR [135.3%(IQR:115.5-150.8) vs. 140.3%(IQR:123.0-172.5),p = 0.039] and dP/dtmax [666mmHg(IQR:489-891) vs. 927mmHg(IQR:693-1092),p<0.001], and a reduction in AIx [154.8%(IQR:138.3-171.0) vs. 133.5%(IQR:128.3-151.8),p<0.001] and AGPH [34.1%(IQR:26.8-39.0) vs. 25.0%(IQR 21.8-33.7),p = 0.002], confirming the beneficial effects of replacing the stenotic valve. No association of these parameters could be revealed with outcome. CONCLUSIONS:PWA is suitable for assessing coronary microcirculation and contractility mirrored by SEVR and maxdP/dt in the setting of aortic stenosis. PWA parameters attributed to vascular properties should be interpreted with caution