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The Prussian blue and polypyrrole nanocomposite (PB–PPy) was synthesised by a facile spontaneous self-assembly (SA) procedure through the layering of multiple sequential absorptions of FeCl3–K3[Fe(CN)6] and pyrrole. The morphology of PB–PPy nanocomposite was rough and irregular, whereas the PB nanocubes (used as experimental control) had a diameter of about 40 nm which were formed using the SA method. The intercalation pseudocapacitive mechanism occurs when potassium ions were inserted to the PB framework. The electrochemical behaviour and areal capacitance of PB–PPy were compared with pristine PB. The “knee frequency” was only present in the Nyquist plot of PB–PPy. The result revealed that the PPy significantly improved the capacitance of pristine PB and this made PB–PPy as a promising candidate for supercapacitors. The specific areal capacitance of PB–PPy was at least ten times higher than pristine PB.

Copper hexacyanoferrate-polypyrrole (CuHCF-PPy) nanocomposite as nicotine electrochemical sensor was deposited directly on reduced graphene oxide (rGO) by a direct self-assembly technique for the first time. FTIR and EDX confirmed the formation of CuHCF-PPy whereas combination of cubic CuHCF-PPy globules morphology was determined by FESEM. The electrochemical properties were studied via CV and its equivalent circuit fitted from EIS was described in details. The linear range of the proposed sensor was between 0.03 and 5 mM, which is the highest among the previous report, with a compatible sensitivity of 0.21 mA·cm−2 mM−1. Additionally, the sensor was applied for the detection of nicotine content in vape (e-cigarette) real sample.

Background Echocardiographic assessment of diastolic function is complex but can aid in the diagnosis of heart failure, particularly in patients with preserved ejection fraction. In 2016, the American Society of Echocardiography (ASE) and European Association of Cardiovascular Imaging (EACVI) published an updated algorithm for the evaluation of diastolic function. The objective of our study was to assess its impact on diastolic function assessment in a real-world cohort of echo studies. Methods We retrospectively identified 71,727 consecutive transthoracic echo studies performed at a tertiary care center between February 2010 and March 2016 in which diastolic function was reported based on the 2009 ASE Guidelines. We then programmed a software algorithm to assess diastolic function in these echo studies according to the 2016 ASE/EACVI Guidelines. Results When diastolic function assessment based on the 2009 guidelines was compared to that using the 2016 guidelines, there were significant differences in proportion of studies classified as normal (23% vs. 32%) or indeterminate (43% vs. 36%) function, and mild (23% vs. 23%), moderate (10% vs. 8%), or severe (1% vs. 2%) diastolic dysfunction, with poor agreement between the two methods (Kappa 0.323, 95% CI 0.318–0.328). Furthermore, within the subgroup of studies with preserved ejection fraction and no evidence of myocardial disease, there was significant reclassification from mild diastolic dysfunction to normal diastolic function. Conclusion The updated guidelines result in significant differences in diastolic function interpretation in the real world. Our findings have important implications for the identification of patients with or at risk for heart failure.

We developed a machine learning model for efficient analysis of echocardiographic image quality in hospitalized patients. This study applied a machine learning model for automated transthoracic echo (TTE) image quality scoring in three inpatient groups. Our objectives were: (1) Assess the feasibility of a machine learning model for echo image quality analysis, (2) Establish the comprehensiveness of real-world TTE reporting by clinical group, and (3) Determine the relationship between machine learning image quality and comprehensiveness of TTE reporting. A machine learning model was developed and applied to TTEs from three matched cohorts for image quality of nine standard views. Case TTEs were comprehensive studies in mechanically ventilated patients between 01/01/2010 and 12/31/2015. For each case TTE, there were two matched spontaneously breathing controls (Control 1: Inpatients scanned in the lab and Control 2: Portable studies). We report the overall mean maximum and view specific quality scores for each TTE. The comprehensiveness of an echo report was calculated as the documented proportion of 12 standard parameters. An inverse probability weighted regression model was fit to determine the relationship between machine learning quality score and the completeness of a TTE report. 175 mechanically ventilated TTEs were included with 350 non-intubated samples (175 Control 1: Lab and 175 Control 2: Portable). In total, the machine learning model analyzed 14,086 echo video clips for quality. The overall accuracy of the model with regard to the expert ground truth for the view classification was 87.0%. The overall mean maximum quality score was lower for mechanically ventilated TTEs (0.55 [95% CI 0.54, 0.56]) versus 0.61 (95% CI 0.59, 0.62) for Control 1: Lab and 0.64 (95% CI 0.63, 0.66) for Control 2: Portable; p = 0.002. Furthermore, mechanically ventilated TTE reports were the least comprehensive, with fewer reported parameters. The regression model demonstrated the correlation of echo image quality and completeness of TTE reporting regardless of the clinical group. Mechanically ventilated TTEs were of inferior quality and clinical utility compared to spontaneously breathing controls and machine learning derived image quality correlates with completeness of TTE reporting regardless of the clinical group.

Prussian blue-polypyrrole (PB-PPy) nanocomposite was deposited directly on glassy carbon electrode (GCE) by self-assembly (SA) based on multiple sequential adsorption of FeCl 3 -K 3 [Fe(CN) 6 ] and pyrrole. This approach offers easy preparation of electrodes, which allows control of its electrochemical behaviour and sensitivity towards hydrogen peroxide (H 2 O 2 ). PB-PPy nanocomposite was also electrodeposited in one-pot aqueous solution for the comparison purpose in terms of morphology and its electrochemical and electrocatalytic behaviours. Field-emission scanning microscope (FESEM) presented the morphology SA PB-PPy nanocomposites was irregular whereas electrodeposited PB-PPy was in nanocubic framework. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were employed to study the electrochemical behaviour of fabricated PB-PPy films. The SA PB-PPy electrode with 10 deposition cycles demonstrated good sensing behaviour towards H 2 O 2 with good selectivity whereas capacitive property was observed when the deposition cycles increased to 20.

Atrial volumes indexed to body surface area (AVI) are robust predictors of nonvalvular atrial fibrillation (AF) recurrence after direct current cardioversion (DCCV). The incremental value of atrial emptying fraction (EmF) compared with atrial volumes as a predictor for recurrent AF after DCCV has not been evaluated. We sought to compare the predictive ability of baseline left atrial (LA) EmF, right atrial (RA) EmF, LAVI, and RAVI for post-DCCV AF recurrence at 6 months. The first 95 patients enrolled in the AF Clinic Registry with adequate echocardiogram imaging constituted the study cohort. Each patient underwent echocardiogram within 6 months before cardioversion. Maximal LAVI and RAVI, LA EmF, and RA EmF were performed offline using 4-chamber single-plane Simpson's method, averaged over 5 cycles. The mean age of the study cohort was 64 ± 12 years, and 67% were men. Only 28 patients (29%) who underwent DCCV remained in sinus rhythm at 6 months of follow-up. The remaining, 67 (71%) had reverted to AF or underwent ablation during the 6 months of follow-up. The overall performance for prediction of AF recurrence was greatest for RA EmF, area under the receiver operator characteristic curve (AUC): RA EmF 0.92, LA EmF 0.89, RAVI 0.76, and LAVI 0.63. RA and LA EmF AUCs were significantly higher than for LAVI or RAVI (max p = 0.02). In conclusion, although RAVI and LAVI are strong predictors of AF recurrence after DCCV, RA and LA EmF outperformed in this cohort.

Mixed valence transition metal hexacyanoferrates (MeHCF)-Prussian blue and its analogs receive enormous research interest in the electrochemical sensing field. In recent years, conducting materials such as conducting polymer, carbon nanomaterial, and noble metals have been used to form nanocomposites with MeHCF. The scope of this review offers the reasons behind the preparation of various MeHCF based nanocomposite toward electrochemical detection. We primarily focus on the current progress of the development of MEHCF-based nanocomposites. The synthesis methods for these nanocomposites are also reviewed and discussed.

Pulmonary artery sarcoma is a rare malignant neoplasm. Here, we describe a patient with a pulmonary artery sarcoma, which was only subtly visible and therefore not fully appreciated on initial transthoracic echocardiogram. Characterization of the tumor was aided by the use of multimodality imaging that included computed tomography, magnetic resonance imaging, and positron emission tomography. Familiarity with its appearance on multiple imaging modalities including echocardiography is important to ensure timely diagnosis, although the optimal treatment strategy is still unknown, and the prognosis remains poor.

Tissue Doppler (TD) imaging is a novel echocardiographic technique that measures myocardial velocities. However, there are sparse data on TD imaging of the right ventricular (RV) free wall in the diagnosis and prognosis of RV myocardial infarction (MI) in inferior wall left ventricular MI. Fifty patients who had left ventricular MI underwent TD echocardiography and angiography within 48 hours of MI. For diagnosis, the ability of RV TD imaging to detect RV MI was assessed using coronary angiography as the reference standard. For prognosis, the ability of TD detection of RV dysfunction to predict cardiac death or rehospitalization at 1 year was determined. For diagnosis, the univariate predictors of RV MI included RV diastolic dimension (p = 0.001), TD imaging of tricuspid annular systolic velocity (p = 0.001), and early diastolic velocity (p = 0.002). On multivariate analysis, systolic annular velocity (p = 0.04) and RV dimension (p = 0.05) predicted RV MI. For prognosis, nonculprit coronary artery disease (p = 0.003), TD imaging of RV systolic annular velocity (p = 0.005), and early diastolic velocity (p = 0.01) were among the univariate predictors of cardiac death or rehospitalization. On multivariate analysis, nonculprit coronary artery disease (p = 0.02) and TD imaging of systolic annular velocity (p = 0.04) were independent predictors of outcome. Decreased RV systolic annular velocity on TD images detects RV MI in first left ventricular acute inferior MI and predicts cardiac death or rehospitalization at 1 year.

Left ventricular filling and pulmonary artery pressure (PAP) have not been well described in patientsor = 90 years old. We reviewed our database to obtain echocardiograms with normal findings in this age group. The peak early and late mitral filling velocities, the early and late velocity-time integral (VTI), the mitral deceleration time, and the atrial filling fraction (late VTI/total VTI) were measured. PAP was obtained from the peak tricuspid regurgitation velocity. Of 252 echocardiograms performed on patientsor = 90 years old, 47 (19%) were normal. The mean +/- SD values were: ratio of peak early and late mitral filling velocities, 0.69 +/- 0.16; deceleration time, 240 milliseconds +/- 31; ratio of early and late VTI, 1.0 +/- 0.3; atrial filling fraction, 47% +/- 7; and PAP, 31 mm Hg +/- 6. Left ventricular filling in patients aged 90 to 100 years demonstrates increasingly impaired left ventricular relaxation from patients in their eighth and ninth decades. PAP continues to increase with age and PAPor = 40 mm Hg in the elderly could be considered normal.

Nanostructured metal oxides, especially zinc oxide, ZnO had attracted great attention for the construction of biosensor due to its high isoelectric point (IEC). This high IEP of ZnO made it a good material for immobilisation of DNA through electrostatic interaction. On the other hand, the good conductivity, large surface area and biocompatibility have made carbon based materials such as reduced graphene oxide, rGO suitable candidate for electrochemical biosensor. In addition, rGO is an unique materials which has the ability to accept the electrons from the photocatalyst, ZnO and to slow down the recombination rate of electron-hole of ZnO. The limitation of ZnO as photocatalyts can be overcomed by forming hybrid with rGO. Thus, we used the rGO-ZnO thin film for biosensing and as photocatalyst for photoinactivation for bacteria in water. In this paper, reduced graphene oxide (rGO) was utilised to form hybrid with zinc oxide (ZnO) by electrodeposition. This rGO-ZnO thin film electrode acted as a hybrid-platform both for electrochemical and photoelectrochemical biosensor for the detection of S.Typhi in water. After biosensing, the same rGO-ZnO thin film, as photocatalyts too, was used to accelerate the sunlight-mediated inactivation of S.Typhi in the water sample. Acknowledgement This research is supported by University Malaya Flagship Grant project FL001A-14AET, and Transdisciplinary Research Grant Scheme (TRGS TR002A-2014) from Malaysian Ministry of Higher Education.

In this study, the effect of type of gases used in pyrolysis on the physical and electrochemical characteristic on SU-8 photoresist derived carbon film fabricated on silicon wafer was been investigated. Pyrolysis process was performed in the presence of nitrogen, argon and helium gas, repectively in temperature of 1100 °C in furnace. Thermogravimetric analysis, Raman spectroscopy, X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy techniques were used to charcterise the surface structure of fabricated carbon film. The electrochemical properties of the SU-8 fabricated thin film was analysed with cyclic voltammetry and electrochemical impedance spectroscopy. The results were then correlated with type of gases in pyrolysis process. Acknowledgement This research is supported by University Malaya Flagship Grant project FL001A-14AET, and Transdisciplinary Research Grant Scheme (TRGS TR002A-2014) from Malaysian Ministry of Higher Education, and MOSTI SF020-2014.

Adjusted subcutaneous heparin was used for thromboembolism prophylaxis during 18 pregnancies in 16 women with an artificial heart valve. Oral warfarin was replaced by subcutaneous heparin as soon as pregnancy was confirmed. The dosage of heparin was adjusted to maintain a partial thromboplastin time at 1.5 times the control value and treatment was administered during the first trimester and the last 3 weeks of gestation. Warfarin was used between the 13th and 37th week. There were no maternal thromboembolic complications and none of the live-born infants showed congenital malformations, indicating that this regimen is effective. However, there were nine spontaneous abortions, including five that occurred in the first 12 weeks. The early abortions were probably related to warfarin exposure at the beginning of pregnancy. The preconception replacement of warfarin by heparin in these patients may be indicated.

We report our experience with the use of a USCI Sones catheter curve A type 1 (7540) to cross the aortic valves of 45 patients with clinically significant aortic stenosis. The technique was successful in all our patients with a fluoroscopic time of less than 3 min. A gradient of up to 200 mmHg across the aortic valve area was recorded, and the smallest valve area calculated was less than 0.2 cm2. The method obviated the need for a guidewire and satisfactory left ventriculograms were obtained. No major complication was observed. We conclude that the technique is a simple, rapid, and safe means of obtaining left ventricular hemodynamic and angiographic information in patients with aortic stenosis of various degrees of severity.

Propafenone is an investigational antiarrhythmic agent with demonstrated effectiveness against a variety of supraventricular and ventricular arrhythmias.1 In vitro and in vivo studies have confirmed its class I activity in suppressing the rate of rise of phase 0 of the action potential by blocking the fast inward sodium current.2 In addition, propafenone has a mild β-blocking effect. Clinically the drug has been shown to slow sinus rate3 and prolong the sinus node recovery time.4 However, advanced sinus node dysfunction leading to symptomatic bradycardia associated with the use of propafenone has been rarely reported. Herein, we report 6 such cases presenting over 3 years.

A 46-year-old lady with leiomyosarcoma of the inferior vena cava extending into the hepatic veins and right atrium is described. The diagnosis was made pre-operatively by a combination of radiological techniques including computed tomography, inferior vena cavography, arteriography, and two-dimensional echocardiography. The clinical presentation, radiological features and management of this condition are reviewed.

Between 1979 and 1982, the efficacy of fixed low-dose heparin, administered subcutaneously as thromboembolic prophylaxis, was studied during 14 pregnancies in 10 patients with mechanical heart valves. Calcium heparin (5000 units every 12 hours) was substituted for warfarin during the first trimester and the last month of pregnancy. Although the regimen was well tolerated and was associated with only 14% of first-trimester abortions, five episodes of thromboembolism occurred in four patients. Thus, this fixed, low-dose heparin regimen did not provide adequate thromboembolic prophylaxis in patients with prosthetic heart valves during pregnancy.

Atrial fibrillation (AF) is associated with progressive atrial enlargement, and mitral annular diameter (MAD) is closely related to the left atrial size. The natural history of mitral annulus remodeling in the context of AF has not been assessed. We aimed to determine the rate of change in MAD over