The Agreement of a Two- and a Three-Dimensional Speckle-Tracking Global Longitudinal Strain.

Background: Two-dimensional (2D) and three-dimensional (3D) speckle-tracking echocardiography (STE) enables assessment of myocardial function. Here, we examined the agreement between 2D and 3D STE measurement of a global longitudinal strain (GLS) in patients with normal left ventricle, reduced ejection fraction, and cardiac pacing. Methods: Our analysis included 90 consecutive patients (59% males; average age: 73.2 ± 11.2 years) examined between May 2019−December 2020, with valid 2D and 3D loops for further speckle-tracking strain analysis. Linear regression, Pearson correlation, and a Bland−Altman plot were used to quantify the association between 2D and 3D GLS and related segments, using the 17-segment American Heart Association (AHA) model. Analyses were performed in the entire study group and subgroups. Intra- and inter-observer variability of 2D and 3D GLS measurement was also performed in all participants. Results: We observed a strong correlation between 2D and 3D GLS measurements (R = 0.76, p < 0.001), which was higher in males (R = 0.78, p < 0.001) than females (R = 0.69, p < 0.001). Associated segment correlation was poor (R = 0.2−0.5, p < 0.01). The correlation between 2D and 3D GLS was weaker in individuals with ventricular pacing of >50% (R = 0.62, p < 0.001) than <50% (R = 0.8, p < 0.001), and in patients with LVEF of <35% (R = 0.69, p = 0.002) than >35% (R = 0.72, p < 0.001). Intra-observer variability for 2D and 3D GLS was 2 and 2.3%, respectively. Inter-observer variability for 2D and 3D GLS was 3.8 and 3.6%, respectively Conclusion: Overall 2D and 3D GLS were closely associated but not when analyzed per segment. It seems that GLS comparison is more representative of global shortening than local displacement. Right ventricular pacing and reduced left ventricular ejection fraction were associated with a reduced correlation between 2D and 3D GLS.

Performance of Seven SARS-CoV-2 Self-Tests Based on Saliva, Anterior Nasal and Nasopharyngeal Swabs Corrected for Infectiousness in Real-Life Conditions: A Cross-Sectional Test Accuracy Study.

Many studies reported good performance of nasopharyngeal swab-based antigen tests for detecting SARS-CoV-2-positive individuals; however, studies independently evaluating the quality of antigen tests utilizing anterior nasal swabs or saliva swabs are still rare, although such tests are widely used for mass testing. In our study, sensitivities, specificities and predictive values of seven antigen tests for detection of SARS-CoV-2 (one using nasopharyngeal swabs, two using anterior nasal swabs and four using saliva) were evaluated. In a setting of a high-capacity testing center, nasopharyngeal swabs for quantitative PCR (qPCR) were taken and, at the same time, antigen testing was performed in accordance with manufacturers' instructions for the respective tests. In samples where qPCR and antigen tests yielded different results, virus culture was performed to evaluate the presence of the viable virus. Sensitivities and specificities of individual tests were calculated using both qPCR and qPCR corrected for viability as the reference. In addition, calculations were also performed for data categorized according to the cycle threshold and symptomatic status. The test using nasopharyngeal swabs yielded the best results (sensitivity of 80.6% relative to PCR and 91.2% when corrected for viability) while none of the remaining tests (anterior nasal swab or saliva-based tests) came even close to the WHO criteria for overall sensitivity. Hence, we advise caution when using antigen tests with alternative sampling methods without independent validation.

Assessment of toe brachial index validity in diabetic patients - interim results.

INTRODUCTION: The toe brachial index (TBI) is recommended for the detection of lower extremity arterial disease (LEAD) in case of reduced efficacy of the ankle brachial index (ABI), which most often occurs in diabetics. In this case, TBI is expected to give more accurate results. There are not many studies dealing with the use of TBI specifically in diabetics and the results are different. OBJECTIVE: The purpose of this work is to present the interim results of the study, whose main objective is to assess the validity of TBI in diabetics and to determine whether this method provides improvements over the ABI. METHODS: In the first phase of the study, 42 limbs were examined in 21 patients with type 2 diabetes. ABI was measured using the automatic oscillometric method (ABI OSC) and the manual method using the pencil doppler (ABI DPP). TBI was determined using an automatic plethysmographic method. The reference examination of the arteries of the lower limbs was performed using duplex ultrasonography (DUS). A paired t-test was used to compare the individual TBI and ABI methods. Cut-off points ABI < 0.9; TBI < 0.7; and DUS stenosis > 50 % were used to evaluate validity parameters. RESULTS: The individual ABI and TBI methods gave different results (p < 0.05). In eight limbs of the total number, LEAD was demonstrated using DUS. The best validity parameters were demonstrated by the TBI - sensitivity 0.88; specificity 0.88; positive predictive value 0.64; negative predictive value 0.97, positive likelihood ratio 7.44; negative likelihood ratio 0.14. The ABI method of calculation, that uses lower systolic blood pressure determined from two measurement sites on the ankle as a numerator, had a higher validity parameters. The ABI OSC did not correctly detect a single limb with stenosis > 50 % in this cohort. CONCLUSION: According to the interim results of this work, the TBI was more suitable for the detection of LEAD in diabetics in comparison with ABI.

Covid-19 antigen testing: better than we know? A test accuracy study.

BACKGROUND: Antigen testing for SARS-CoV-2 is considered to be less sensitive than the standard reference method - real-time PCR (RT-PCR). It has been suggested that many patients with positive RT-PCR 'missed' by antigen testing might be non-infectious. METHODS: In a real-world high-throughput setting for asymptomatic or mildly symptomatic patients, 494 patients were tested using RT-PCR as well as a single lateral flow antigen test (Ecotest, AssureTech, China). Where the results differed, virus viability was evaluated by cell culture. The test parameters were calculated with RT-PCR and RT-PCR adjusted on viability as reference standards. RESULTS: The overall sensitivity of the used antigen test related to the RT-PCR only was 76.2%, specificity was 97.3%. However, 36 out of 39 patients 'missed' by the antigen test contained no viable virus. After adjusting on that, the sensitivity grew to 97.7% and, more importantly for disease control purposes, the negative predictive value reached 99.2%. CONCLUSIONS: We propose that viability testing should be always performed when evaluating a new antigen test. A well-chosen and validated antigen test provides excellent results in identifying patients who are shedding viable virus (although some caveats still remain) in the real-world high-throughput setting of asymptomatic or mildly symptomatic individuals.

Five Antigen Tests for SARS-CoV-2: Virus Viability Matters.

Antigen testing for SARS-CoV-2 (AGT) is generally considered inferior to RT-PCR testing in terms of sensitivity. However, little is known about the infectiousness of RT-PCR positive patients who pass undetected by AGT. In a screening setting for mildly symptomatic or asymptomatic patients with high COVID-19 prevalence (30-40%), 1141 patients were tested using one of five AGTs and RT-PCR. Where the results differed, virus viability in the samples was tested on cell culture (CV-1 cells). The test battery included AGTs by JOYSBIO, Assure Tech, SD Biosensor, VivaChek Biotech and NDFOS. Sensitivities of the ATGs compared to RT-PCR ranged from 42% to 76%. The best test yielded a 76% sensitivity, 97% specificity, 92% positive, and 89% negative predictive values, respectively. However, in the best performing ATG tests, almost 90% of samples with "false negative" AGT results contained no viable virus. Corrected on the virus viability, sensitivities grew to 81-97% and, with one exception, the tests yielded high specificities >96%. Performance characteristics of the best test after adjustment were 96% sensitivity, 97% specificity, 92% positive, and 99% negative predictive values (high prevalence population). We, therefore, believe that virus viability should be considered when assessing the AGT performance. Also, our results indicate that a well-performing antigen test could in a high-prevalence setting serve as an excellent tool for identifying patients shedding viable virus. We also propose that the high proportion of RT-PCR-positive samples containing no viable virus in the group of "false negatives" of the antigen test should be further investigated with the aim of possibly preventing needless isolation of such patients.

Cardiac Strains As a Tool for Optimization of Cardiac Resynchronization Therapy in Non-responders: a Pilot Study.

BACKGROUND: Approximately 30% of patients do not respond to implantation of Cardiac Resynchronization Therapy - Defibrillators (CRT-D). The aim of this study was to investigate the potential for cardiac strain speckle tracking to optimize the performance of CRT-D in non-responding patients. METHODS: 30 patients not responding to Cardiac Resynchronization Therapy-Defibrillators after 3 months were randomly divided into control and intervention groups. Atrioventricular interval was adjusted so that E and A waves did not overlap, the interventricular interval was subsequently optimized to yield maximum improvement of the sum of longitudinal+radial+circumferential strains. The left ventricular ejection fraction (LVEF) and NYHA improvement 3 months after optimization were evaluated and use of other strain combinations assessed. RESULTS: A significant correlation between the (combined) strain change and LVEF improvement was detected (p<0.01). 75% of patients with non-ischemic etiology of heart failure who did not respond to the original CRT-D reacted favorably with significant LVEF and NYHA improvement. The area strain was the best predictor of LVEF/NYHA improvement in those patients. No significant improvement was recorded in patients with ischemic etiology. CONCLUSIONS: AV and VV optimization based on speckle tracking is a very promising method potentially leading to a significant improvement of the outcome of CRT-D, especially in patients with non-ischemic etiology of heart failure.

Comparison of different methods of ABI acquisition for detection of peripheral artery disease in diabetic patients.

BACKGROUND: Ankle brachial index (ABI) is the principal screening method for peripheral arterial disease (PAD). In this study, we compare various types of Doppler-derived and oscillometric ABIs with results obtained through duplex ultrasonography. METHODS: 62 patients were enrolled in the study. For each limb, blood pressures for both ankle arteries and the arm were measured using Doppler and an automated oscillometric device. Duplex ultrasound was performed for all limbs and occlusions >50% were considered PAD-positive. ABI was calculated using both higher (HABP) and lower (LABP) arterial blood pressure on the individual limbs and the ability to predict duplex-detected stenoses was evaluated. RESULTS: LABP calculation provided results superior to the guideline-recommended HABP. Considering patients with ABI >1.4 or measurement failure as PAD-positive further enhanced the test parameters. The higher ABI cut-off of 1.0 resulted in somewhat better sensitivities (max 92%) and negative predictive values (max 87%) at the expense of a substantial increase in the number of false positives. Oscillometric method yielded poor sensitivities but very good specificities (max 94%) and positive predictive values (max 90%). CONCLUSIONS: Doppler-based LABP provides better results than the guideline-recommended HABP in diabetic patients, nevertheless even this method is not perfect. Increasing the cut-off value to 1.0 in these patients does not bring a substantial improvement of the test performance. Patients with high ABI should be automatically considered PAD-positive and referred for further investigation using imaging techniques.

Out-of-hospital cardiac arrest.

Out-of-hospital cardiac arrest (OHCA) is a leading cause of death in developed industrial countries. The global worldwide average of OHCA incidence in adults is 95.9/100,000/year. European incidences vary according to source from 16 to 119/100,000/year. The aim of this study was to provide an overview of current information on OHCA. The incidences in various populations are discussed, along with the factors affecting the prognosis and outcome of these patients. The etiology and pathophysiological mechanisms are also described, especially in relation to the most common causes - acute and chronic forms of coronary artery disease and cardiomyopathies. Measures that could improve survival rates are discussed, with emphasis on the role of the general public and deployment of automatic external defibrillators.

Validity and Reliability of the Czech Version of the Amsterdam Preoperative Anxiety and Information Scale (APAIS).

PURPOSE: The purpose of this study was to validate the Czech version of the Amsterdam Preoperative Anxiety and Information Scale (APAIS) in adult patients undergoing elective surgery. DESIGN: A cross-sectional study. METHODS: Data were collected from July 2012 to January 2013. For reliability and validity testing, two instruments measuring preoperative anxiety were administered to the participants on the same occasion, (APAIS and the Spielberg State Anxiety Inventory (STAI-S)). The sample consisted of 344 patients undergoing elective surgery. FINDINGS: Reliability of APAIS anxiety subscale measured by Cronbach's alpha was 0.91. Reliability of APAIS information subscale measured by Cronbach's alpha was 0.78. The APAIS anxiety subscale correlated significantly with the STAI-S (0.69). Women scored significantly higher on anxiety scales than men. CONCLUSIONS: APAIS may be a useful tool to measure preoperative anxiety in Czech patients undergoing elective surgery.