Von Willebrand factor as a biological sensor of blood flow to monitor percutaneous aortic valve interventions.

RATIONALE: Percutaneous aortic valve procedures are a major breakthrough in the management of patients with aortic stenosis. Residual gradient and residual aortic regurgitation are major predictors of midterm and long-term outcome after percutaneous aortic valve procedures. We hypothesized that (1) induction/recovery of high molecular weight (HMW) multimers of von Willebrand factor defect could be instantaneous after acute changes in blood flow, (2) a bedside point-of-care assay (platelet function analyzer-closure time adenine DI-phosphate [PFA-CADP]), reflecting HMW multimers changes, could be used to monitor in real-time percutaneous aortic valve procedures. OBJECTIVE: To investigate the time course of HMW multimers changes in models and patients with instantaneous induction/reversal of pathological high shear and its related bedside assessment. METHODS AND RESULTS: We investigated the time course of the induction/recovery of HMW multimers defects under instantaneous changes in shear stress in an aortic stenosis rabbit model and in patients undergoing implantation of a continuous flow left ventricular assist device. We further investigated the recovery of HMW multimers and monitored these changes with PFA-CADP in aortic stenosis patients undergoing transcatheter aortic valve implantation or balloon valvuloplasty. Experiments in the aortic stenosis rabbit model and in left ventricular assist device patients demonstrated that induction/recovery of HMW multimers occurs within 5 minutes. Transcatheter aortic valve implantation patients experienced an acute decrease in shear stress and a recovery of HMW multimers within minutes of implantation which was sustained overtime. In patients with residual high shear or with residual aortic regurgitation, no recovery of HMW multimers was observed. PFA-CADP profiles mimicked HMW multimers recovery both in transcatheter aortic valve implantation patients without aortic regurgitation (correction) and transcatheter aortic valve implantation patients with aortic regurgitation or balloon valvuloplasty patients (no correction). CONCLUSIONS: These results demonstrate that variations in von Willebrand factor multimeric pattern are highly dynamic, occurring within minutes after changes in blood flow. It also demonstrates that PFA-CADP can evaluate in real time the results of transcatheter aortic valve procedures.

Automated 3D analysis of multislice computed tomography to define the line of perpendicularity of the aortic annulus and of the implanted valve: benefit on planning transcatheter aortic valve replacement.

AIMS: We aimed to determine whether preprocedural analysis of multislice computed tomography (MDCT) scan could accurately predict the "line of perpendicularity" (LP) of the aortic annulus and corresponding C-arm angulations required for prosthesis delivery. METHODS AND RESULTS: A 3D analysis of preprocedural MDCT dedicated to define the LP of the aortic annulus was performed in 60 consecutive patients referred for transcatheter aortic valve replacement (TAVR). In 24 patients, the analysis was performed retrospectively to evaluate reproducibility. In 11 patients of this cohort, additional fluoroscopy and MDCT were performed postprocedure to compare the LP of the aortic annulus and the LP of the implanted bioprosthesis. In 36 patients, the analysis was performed prospectively and the results were available at the time of the procedure. In those 36 patients, the postprocedure fluoroscopy-defined LP of the implanted bioprosthesis was used to validate the LP of the aortic annulus as predicted by MDCT. Intraobserver and interobserver reproducibility of the 3D analysis of MDCT to define the LP of the aortic annulus (κ = 1 and 0.94, respectively) and of the bioprosthesis (κ= 1 and 1, respectively) were excellent. Comparison between the LP of the aortic annulus and the LP of the bioprosthesis showed that the two LPs were virtually identical, demonstrating both self-centering of the device during implantation and the possibility to use the LP of the implanted bioprosthesis as a surrogate of the LP of the aortic annulus. In the prospective cohort, the ability of MDCT analysis to predict the LP of the aortic annulus was very good (accuracy = 94% and κ = 0.89). CONCLUSION: Automated 3D analysis of preimplantation MDCT accurately predicts the LP of the aortic annulus and the corresponding C-arm position required for TAVR.

Near-fatal tramadol cardiotoxicity in a CYP2D6 ultrarapid metabolizer.

BACKGROUND: Tramadol is a synthetic, centrally acting analgesic for the treatment of moderate to severe pain. The marketed tramadol is a racemic mixture containing 50% (+)tramadol and 50% (-)tramadol and is mainly metabolized to O-desmethyltramadol (M1) by the cytochrome P450 CYP2D6. Tramadol is generally considered to be devoid of any serious adverse effects of traditional opioid receptor agonists, such as respiratory depression and drug dependence. CASE REPORT: A 22-year-old Caucasian female patient was admitted to our ICU in refractory cardiac arrest requiring extracorporeal membrane oxygenation. This aggressive support allowed resolution of multi-organ dysfunction syndrome. Repeated blood analyses using liquid chromatography-tandem mass spectrometry confirmed high concentrations of both tramadol and its main metabolite O-desmethyltramadol. Genotyping of CYP2D6 revealed the patient to be heterozygous for a duplicated wild-type allele, predictive of a CYP2D6 ultrarapid metabolizer (UM) phenotype, confirmed by calculation of the tramadol/M1 (MR1) metabolic ratio at all time points. DISCUSSION: We here report a case of near-fatal isolated tramadol cardiotoxicity. Because of the inhibition of norepinephrine reuptake, excessive blood epinephrine levels in this CYP2D6R UM patient following excessive tramadol ingestion could explain the observed strong myocardial stunning. This patient admitted intermittent tramadol consumption to gain a "high" sensation. In patients with excessive morphinomimetic effects, levels of tramadol and its main metabolite M1could be measured, ideally combined with CYP2D6 genotyping, to identify individuals at risk of tramadol-related cardiotoxicity. Tramadol treatment could be optimized in these at-risk individuals, consequently improving patient outcome and safety.

Accuracy of script concordance tests in fourth-year medical students.

OBJECTIVES: This investigation aimed to determine the validity of script concordance test (SCT), compared with clinical-case-related short-answer management problems (SAMP), in fourth-year medical students. METHODS: This retrospective study was conducted at the Medical School of Lille University. Cardiology and gynecology examinations both included 3 SCT and 2 clinical-case-related SAMP.  Final score did not include SCT results, and was out of 20 points. The passing score was ≥10/20. Wilcoxon and McNemar tests were used to compare quantitative and qualitative variables, respectively. Correlation between scores was also analyzed. RESULTS: A total of 519 and 521 students completed SAMP and SCT in cardiology and gynecology, respectively. Cardiology score was significantly higher in SCT than SAMP (mean ± SD 13.5±2.4 versus 11.4±2.6, Wilcoxon test, p<0.001). In gynecology, SCT score was significantly lower than SAMP score (10.8±2.6 versus 11.4±2.7, Wilcoxon test, p=0.001). SCT and SAMP scores were significantly correlated (p <0.05, Pearson's correlation). However, percentage of students with SCT score ≥ 10/20 was similar among those who passed or failed cardiology (327 of 359 (91%) vs 146 of 160 (91%), χ2=0.004, df =1, p=0.952), or gynecology (274 of 379 (65%) vs 84 of 142 (59%), χ2=1.614, df=1, p=0.204) SAMP test. Cronbach alpha coefficient was 0.31 and 0.92 for all SCT and SAMP, respectively. CONCLUSIONS:  Although significantly correlated, the scores obtained in SCT and SAMP were significantly different in fourth-year medical students. These findings suggest that SCT should not be used for summative purposes in fourth-year medical students.

Meta-Analysis of Abdominal Aortic Aneurysm in Patients With Coronary Artery Disease.

The high coronary artery disease (CAD) prevalence in patients with abdominal aortic aneurysm (AAA) is well known. However, the inverse relation has been little explored. We present, based on a systematic review and meta-analysis of the published evidence, a critical appraisal of the issue of AAA prevalence and also AAA predictive risk factors in patients with CAD, comparing it with AAA prevalence in subjects without CAD. A total of 22 studies involving 13,388 patients with CAD met the inclusion criteria. Overall, AAA prevalence in patients with CAD was 8.4% (95% confidence interval [CI] 6.9 to 10.3), significantly higher than in subjects without CAD (odds ratio [OR] 2.42, 95% CI 2.08 to 2.81). Pooled analysis revealed that smoking, arterial hypertension, and concomitant carotid artery stenosis were significantly associated with AAA in patients with CAD (OR 1.72, 95% CI 1.14 to 2.61; OR 1.57, 95% CI 1.06 to 2.35; OR 2.14, 95% CI 1.20 to 3.79, respectively). In patients with CAD, AAA prevalence tended to be higher with concomitant peripheral artery disease (OR 2.66, 95% CI 0.82 to 8.61, p = 0.08). In conclusion, AAA prevalence was significantly higher in patients with CAD versus subjects without CAD.

Alterations in neutrophil production and function at an early stage in the high-fructose rat model of metabolic syndrome.

BACKGROUND: Although neutrophils are crucially involved in inflammation, they have received only little attention in metabolic syndrome (MetS). We hypothesized that neutrophil infiltration into adipose tissue (AT) may occur at an early stage of MetS, in association with modulation of major functions of neutrophils and of their bone marrow production. METHODS: Fifty-six male Sprague-Dawley rats were fed regular (control rats (CRs)) or high-fructose (60%; fructose-fed rats (FFRs)) diets. After 6 weeks, metabolic parameters were measured. Distribution of neutrophils into AT was investigated by immunohistochemistry. Function of circulating neutrophils (activation, reactive oxygen species production, phagocytosis, and apoptosis) was determined by flow cytometry. Granulopoiesis was evaluated by measuring the number and survival characteristics of neutrophil progenitors using bone marrow culture assays and flow cytometry. RESULTS: Compared with the CR group, the FFR group developed MetS (i.e., arterial hypertension, hypertriglyceridemia, fasting hyperglycemia, and greater intra-abdominal AT volume) and presented higher neutrophil infiltration into AT. At resting state, no significant difference for circulating neutrophil functions was observed between the 2 groups. In contrast, circulating neutrophils from the FFR group exhibited higher responses to phorbol-12-myristate-13-acetate for all studied functions, compared with the CR group, suggesting that early MetS induces neutrophil priming. In parallel, a diminished clonal capacity and an increased apoptosis in bone marrow-derived granulocyte progenitors and neutrophil precursors were observed in the FFR group compared with the CR group. CONCLUSIONS: These results provide evidence of an increased infiltration into intra-abdominal AT and modified production, function, and phenotype of neutrophils at an early stage of high-fructose diet-induced MetS.

Automated 3D analysis of pre-procedural MDCT to predict annulus plane angulation and C-arm positioning: benefit on procedural outcome in patients referred for TAVR.

OBJECTIVES: The aim of this study was to determine whether pre-procedural analysis of multidetector row computed tomography (MDCT) scans could accurately predict the "line of perpendicularity" (LP) of the aortic annulus and corresponding C-arm angulations required for prosthesis delivery and impact the outcome of the procedure. BACKGROUND: Optimal positioning of the transcatheter aortic prosthesis is paramount to transcatheter aortic valve replacement (TAVR) procedural success. METHODS: All patients referred for TAVR at our center underwent a routine pre-procedural MDCT scan. A 3-dimensional (3D) analysis using software dedicated to define the LP of the aortic annulus and the corresponding C-arm positioning was performed in 71 consecutive patients. In 35 patients, the results of the MDCT analysis were not available at the time of the procedure (angiography cohort). In that cohort the position of the C-arm was determined during the procedure using ad-hoc angiography. In 36 patients, the MDCT analysis was performed pre-procedure and results were available at the time of the procedure (MDCT cohort). In that cohort the position of the C-arm was derived from the MDCT analysis rather than by ad-hoc angiography. RESULTS: Intraobserver and interobserver reproducibility of MDCT analysis to predict the LP of the aortic annulus were excellent (kappa = 1 and 0.94, respectively). Patient variations of the LP ranged >70°. Compared with the angiography cohort, the MDCT cohort was associated with a significant decrease in implantation time (p = 0.0001), radiation exposure (p = 0.02), amount of contrast (p = 0.001), and risk of acute kidney injury (p = 0.03). Additionally, the combined rate of valve malposition and aortic regurgitation was also reduced (6% vs. 23%, p = 0.03). CONCLUSIONS: Automated 3D analysis of pre-implantation MDCT accurately predicts the LP of the aortic annulus and the corresponding C-arm position required for TAVR. With this approach, the implantation of the balloon-expandable prosthetic valve can be performed without an aortogram in the majority of cases and still be safe, with a low rate of valve malpositioning and regurgitation.

Frequency of abdominal aortic aneurysm in patients undergoing coronary artery bypass grafting.

The aims of this study were to clarify the prevalence and the risk factors for unsuspected abdominal aortic aneurysm (AAA) in patients who underwent coronary artery bypass grafting for severe coronary artery disease and to identify the most at risk patients for AAA. Among 217 patients (189 men, mean age 64 +/- 11 years), asymptomatic AAAs, as prospectively identified by echocardiography, were found in 15 patients (6.9%). All patients with AAAs were men and smokers or past smokers. Factors significantly associated by univariate analysis with asymptomatic AAA presence were smoking (p = 0.003), symptomatic peripheral artery disease (p = 0.006), significant carotid artery stenosis (p = 0.007), and larger femoral and popliteal diameters (p = 0.008 and p = 0.0012, respectively). The other classic demographic, clinical, and biologic features were equally distributed among patients. In conclusion, in patients who underwent coronary artery bypass grafting who were men and aged <75 years with smoking histories, the prevalence of AAA was as high as 24% when they had concomitant peripheral arterial disease and/or carotid artery stenosis (vs 4.4% in the absence of either condition, p = 0.007), justifying consideration of AAA screening in this subgroup of in-hospital patients.