Myocardial CT perfusion imaging for the detection of obstructive coronary artery disease: multisegment reconstruction does not improve diagnostic performance

Background: Multisegment reconstruction (MSR) was introduced to shorten the temporal reconstruction window of computed tomography (CT) and thereby reduce motion artefacts. We investigated whether MSR of myocardial CT perfusion (CTP) can improve diagnostic performance in detecting obstructive coronary artery disease (CAD) compared with halfscan reconstruction (HSR). Methods: A total of 134 patients (median age 65.7 years) with clinical indication for invasive coronary angiography and without cardiac surgery prospectively underwent static CTP. In 93 patients with multisegment acquisition, we retrospectively performed both MSR and HSR and searched both reconstructions for perfusion defects. Subgroups with known (n = 68) or suspected CAD (n = 25) and high heart rate (n = 30) were analysed. The area under the curve (AUC) was compared applying DeLong approach using >= 50% stenosis on invasive coronary angiography as reference standard. Results: Per-patient analysis revealed the overall AUC of MSR (0.65 [95% confidence interval 0.53, 0.78]) to be inferior to that of HSR (0.79 [0.69, 0.88]; p = 0.011). AUCs of MSR and HSR were similar in all subgroups analysed (known CAD 0.62 [0.45, 0.79] versus 0.72 [0.57, 0.86]; p = 0.157; suspected CAD 0.80 [0.63, 0.97] versus 0.89 [0.77, 1.00]; p = 0.243; high heart rate 0.46 [0.19, 0.73] versus 0.55 [0.33, 0.77]; p = 0.389). Median stress radiation dose was higher for MSR than for HSR (6.67 mSv versus 3.64 mSv, p < 0.001). Conclusions: MSR did not improve diagnostic performance of myocardial CTP imaging while increasing radiation dose compared with HSR

Valve in valve implantation of the CoreValve Evolut R in degenerated surgical aortic valves

Background: The new CoreValve Evolut R has an improved design to minimize paravalvular leak­age and allows repositioning of the valve. For patients with degenerated bioprosthetic aortic valves, transcatheter aortic valve implantation (TAVI) represents a less invasive option. Herein reported are valve-in-valve (ViV) implantations of this new valve. Methods: A total of 26 patients (mean age 79.4 ± 6.1 years, 17 males and 9 females) were treated for severe prosthesis stenosis (n = 9), severe regurgitation (n = 8) or severe combination of stenosis and regurgitation (n = 9). All patients underwent transthoracic echocardiography before and after ViV implantation. Results: Valve-in-valve implantation of a CoreValve Evolut R was performed successfully in all pa­tients. The mean transaortic gradient for stenotic valves determined by transthoracic echocardiography was reduced significantly from 37.5 ± 15.3 mmHg in patients with prosthesis stenosis to 16.3 ± 8.2 mmHg (p &lt; 0.001). In all cases with severe prosthesis regurgitation, regurgitation was reduced to none or mild. All-cause mortality after 30 days was 0%. Conclusions: It was concluded that CoreValve Evolut R is well suited for ViV implantation

Low permanent pacemaker rates following Lotus device implantation for transcatheter aortic valve replacement due to modified implantation protocol

Background: Conduction disturbances requiring permanent pacemaker implantation following transcatheter aortic valve replacement (TAVR) are a common problem. Pacemaker implantation rates after TAVR appear to be higher compared to conventional aortic valve replacement. The aim of this study was to analyze whether a high annulus implantation conveys the benefit of a decreased rate of permanent pacemaker implantation while being safe and successful according to Valve Academic Research Consortium 2 (VARC2)-criteria. Methods: A total of 23 patients with symptomatic severe aortic valve stenosis, an aortic annulus of 19–27 mm and at high risk for surgery were treated with the Lotus valve. In all patients the valve was implanted in a high annulus position via femoral access. The primary device performance endpoint was VARC2-defined device success after 30 days and the primary safety endpoint was the need for permanent pacemaker implantation. Results: The mean age was 73.23 ± 7.65 years, 46% were female, 38% were New York Heart Association class III/IV at baseline. Thirty-day follow-up data were available for all patients. The VARC2-defined device success rate after 30 days was 22/23 (96%). 2/21 (10%) patients required a newly implanted pacemaker due to 3rd degree atrioventricular block. 25% of the patients developed a new left bundle branch block after valvuloplasty or device implantation. 21 of the 23 patients (96%) had no other signs of conduction disturbances after 30 days. Conclusions: The approach of the modified implantation technique of Lotus TAVR device was safe and effective. The incidence of need for a permanent pacemaker following TAVR could be significantly reduced due to adopted implantation protocol

Impact of inferior caval valve implantation on severity of tricuspid regurgitation and right heart function

Aims: Severe tricuspid regurgitation (TR) is a common finding in heart failure patients and associated with increased mortality. New interventional therapeutic options are needed as many heart failure patients are unfit for surgery. The TRICAVAL study compared valve implantation into the inferior vena cava (CAVI) with optimal medical therapy (OMT) in patients with severe TR. Here, we report details on the impact of CAVI on TR severity as well as right heart function and morphology. Methods and results: We randomized 28 patients with severe TR to CAVI (n = 14) with transfemoral implantation of an Edwards Sapien XT valve into the inferior vena cava or OMT (n = 14). Inclusion and exclusion criteria were based on anatomical and clinical parameters. Echocardiographic measurements were performed at baseline, at the first postoperative day and one, three, and twelve months after randomization. As proof of concept of an effective sealing of the inferior vena cava, we detected a significant decrease in systolic hepatic vein reflux volume (11.0 [6.2-21.9] mL vs 3.5 [0.6-8.5] mL,P = .016) and hepatic vein diameter (11.5 [10.0-14.8] mm vs 10.0 [9.3-11.8] mm,P = .034) at thirty-day follow-up. However, CAVI had no significant impact on TR, cardiac function, and morphology. Conclusions: Caval valve implantation significantly reduced systolic reflux into the hepatic veins but was not associated with an improvement in cardiac function, morphology, or TR severity

Renal and hepatic function of patients with severe tricuspid regurgitation undergoing inferior caval valve implantation

Due to progressive abdominal-venous congestion severe tricuspid regurgitation (TR) is a common cause of cardiorenal and cardiohepatic syndrome. We initiated the TRICAVAL study to compare interventional valve implantation into the inferior vena cava (CAVI) versus optimal medical therapy (OMT) in severe TR. In the present subanalysis, we aimed to evaluate the effects of CAVI on clinical signs of congestion, renal and hepatic function. TRICAVAL was an investigator-initiated, randomized trial. Twenty-eight patients with severe TR were randomized to OMT or CAVI using an Edwards Sapien XT valve. Probands who completed the 3-month follow-up (CAVI [n = 8], OMT [n = 10]) were evaluated by medical history, clinical examination, and laboratory testing at baseline, 3 and 12 months. After 3 months, the CAVI group exhibited a significant reduction of body weight (from 80.7 [69.0-87.7] kg to 75.5 [63.8-84.6] kg, p < 0.05) and abdominal circumference (from 101.5 +/- 13.8 cm to 96.3 +/- 15.4 cm, p <= 0.01) and a trend to lower doses of diuretics compared to OMT. Renal and hepatic function parameters did not change significantly. Within a short-term follow-up, CAVI led to an improvement of clinical signs of venous congestion and a non-significant reduction of diuretic doses compared to OMT

Clinical pre-test probability for obstructive coronary artery disease: insights from the European DISCHARGE pilot study

Computed tomography angiography; Prevalence; Probability of diseaseAngiografía por tomografía computarizada; Prevalencia; Probabilidad de enfermedadAngiografia per tomografia computaritzada; Prevalència; Probabilitat de malaltiaObjectives To test the accuracy of clinical pre-test probability (PTP) for prediction of obstructive coronary artery disease (CAD) in a pan-European setting. Methods Patients with suspected CAD and stable chest pain who were clinically referred for invasive coronary angiography (ICA) or computed tomography (CT) were included by clinical sites participating in the pilot study of the European multi-centre DISCHARGE trial. PTP of CAD was determined using the Diamond-Forrester (D+F) prediction model initially introduced in 1979 and the updated D+F model from 2011. Obstructive coronary artery disease (CAD) was defined by one at least 50% diameter coronary stenosis by both CT and ICA. Results In total, 1440 patients (654 female, 786 male) were included at 25 clinical sites from May 2014 until July 2017. Of these patients, 725 underwent CT, while 715 underwent ICA. Both prediction models overestimated the prevalence of obstructive CAD (31.7%, 456 of 1440 patients, PTP: initial D+F 58.9% (28.1–90.6%), updated D+F 47.3% (34.2–59.9%), both p < 0.001), but overestimation of disease prevalence was higher for the initial D+F (p < 0.001). The discriminative ability was higher for the updated D+F 2011 (AUC of 0.73 95% confidence interval [CI] 0.70–0.76 versus AUC of 0.70 CI 0.67–0.73 for the initial D+F; p < 0.001; odds ratio (or) 1.55 CI 1.29–1.86, net reclassification index 0.11 CI 0.05–0.16, p < 0.001). Conclusions Clinical PTP calculation using the initial and updated D+F prediction models relevantly overestimates the actual prevalence of obstructive CAD in patients with stable chest pain clinically referred for ICA and CT suggesting that further refinements to improve clinical decision-making are needed.Open Access funding provided by Projekt DEAL. The DISCHARGE project is funded by the EU-FP7 Framework Programme (FP7 2007-2013, EC-GA 603266, EC-GA 603266) but the clinical sites did not receive any funding for the pilot study which was an own contribution by all. Only the research staff at the coordinator site received funding for coordinating the pilot study

SDRP JOURNAL OF BIOMEDICAL ENGINEERING 2016 Research Electrochemical characterization of vascular bare-metal stents. A novel approach modifying the mini-cell system

ABSTRACT: Electrochemical characterization of stents can be seen as a key to assessing their biocompatibility. The aim of the present study was to investigate the electrochemical properties of bare-metal stent surfaces. The minicell system (MCS) was modified to record open circuit potential (OCP), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) on NiTi, FeCrNi and CoCr stents using 1%NaCl, PBS and serum. Surfaces were examined by scanning electron microscopy (SEM) and energy-dispersive X-ray microanalysis (EDX) before and after electrochemical testing. CV showed passivity breakdown of FeCrNi and CoCr in 1%NaCl. Corrosion properties were inhomogeneous. Several surfaces of FeCrNi showed progressive activation and passivity breakdown while pitting was detected by SEM. EDX showed a decrease in Fe, Cr and Ni and an excessive presence of Cl. Corrosion rates (vcorr) were partially significantly different between the examined materials and electrolytes (e.g. using 1%NaCl: vcorr[FeCrNi]=2.08x10 -2 ±1.14x10 -2 μm/y vs. [NiTi]=9.41x10 -3 ±1.87x10 -3 μm/y; p&lt;0.001). EIS circuit diagrams indicated oxide films on passivated metal surfaces. The modified MCS is promising to assess the biocompatibility of stents via electrochemical analytics. Overall, the vcorr of all stents were below the required limit values

Role of Kozak sequence polymorphism of platelet glycoprotein Ibα as a risk factor for coronary artery disease and catheter interventions

AbstractOBJECTIVESWe sought to determine the role of the −5T/C polymorphism of the platelet glycoprotein (GP) Ibα as a potential risk factor for coronary artery disease (CAD) and adverse events complicating a coronary catheter intervention.BACKGROUNDThe platelet GP Ib-IX-V receptor complex plays a crucial role in arterial thrombus formation. The −5T/C polymorphism of GP Ibα is associated with increased receptor density.METHODSWe genotyped 1,000 patients with angiographically confirmed CAD, as well as 1,000 age- and gender-matched control subjects, for this polymorphism by polymerase chain reaction/restriction fragment length polymorphism. Among the patients with CAD, 269 underwent percutaneous transluminal coronary angioplasty (PTCA), 103 underwent directional coronary atherectomy and 278 underwent stenting. This intervention group was followed for a 30-day composite end point of target vessel revascularization, myocardial infarction or death.RESULTSCarriers of the −5C allele were significantly over-represented in the group of patients developing acute coronary syndromes (relative risk [RR] 1.43, 95% confidence interval [CI] 1.05 to 1.95, p = 0.02). The −5C allele furthermore predicted an increased risk for developing complications after PTCA (RR 3.75, 95% CI 1.15 to 12.27, p = 0.029).CONCLUSIONSThe −5C allele of the GP Ibα Kozak polymorphism may represent a risk factor in clinical conditions in which thrombosis plays an important role, such as in acute coronary syndromes and in complications after PTCA