Left atrial strain, embolic stroke of undetermined source, and atrial fibrillation detection.

BACKGROUND: Atrial cardiopathy is a proposed mechanism of embolic stroke of undetermined source (ESUS). Left atrial (LA) strain may identify early atrial cardiopathy prior to structural changes. We aim to study the associations between LA strain, ESUS, and atrial fibrillation (AF) detection in ESUS. METHODS: The study population included patients with ESUS and noncardioembolic (NCE) stroke presenting to the Rhode Island Hospital Stroke Center between January 2016 and June 2017 who underwent transthoracic echocardiography. Speckle tracking echocardiography (STE) was used to measure the three phases of LA strain (reservoir, conduit, and contractile). Binary logistic regression analysis was performed to determine the associations between LA strain and stroke subtype (ESUS vs. NCE) as well as follow-up detection of AF in ESUS patients. RESULTS: We identified 656 patients, 307 with ESUS and 349 with NCE. In binary logistic regression, the lowest tertiles of LA reservoir (adjusted OR 1.944, 95% CI 1.266-2.986, p = .002), contractile (aOR 1.568, 95% CI 1.035-2.374, p = .034), and conduit strain (aOR 2.288, 95% CI 1.448-3.613, p = .001) were more likely to be significantly associated with ESUS compared to NCE stroke. Among all ESUS patients, the lowest tertiles of LA reservoir strain (OR 2.534, 95% CI 1.029-6.236, p = .043), contractile strain (OR 2.828, 95% CI 1.158-6.903, p = .022), and conduit strain (OR 2.614, 95% CI 1.003-6.815, p = .049) were significantly associated with subsequent detection of AF. CONCLUSION: Reduced LA strain is associated with ESUS occurrence and AF detection in ESUS patients. Therefore, quantification of LA strain in ESUS patients may improve risk stratification and guide secondary prevention strategies.

Evaluating left atrial strain and left ventricular diastolic strain rate as markers for diastolic dysfunction in patients with mitral annular calcification.

BACKGROUND: Mitral annular calcification (MAC) poses many challenges to the evaluation of diastolic function using standard echocardiography. Left atrial (LA) strain and left ventricular early diastolic strain rate (DSr) measured by speckle-tracking echocardiography (STE) are emerging techniques in the noninvasive evaluation of diastolic function. We aim to evaluate the utility of LA strain and early DSr in predicting elevated left ventricular filling pressures (LVFP) in patients with MAC and compare their effectiveness to ratio of mitral inflow velocity in early and late diastole (E/A). METHODS: We included adult patients with MAC who presented between January 1 and December 31, 2014 and received a transthoracic echocardiogram (TTE) and cardiac catheterization with measurement of LVFP within a 24-h period. We used Spearman's rank correlation coefficient to assess associations of LA reservoir strain and average early DSr with LVFP. Receiver operating characteristic (ROC) curves were computed to assess the effectiveness of LA strain and DSr in discriminating elevated LVFP as a dichotomized variable and to compare their effectiveness with E/A ratio categorized according to grade of diastolic dysfunction. RESULTS: Fifty-five patients were included. LA reservoir strain demonstrated poor correlation with LVFP (Spearman's rho = 0.03, p = 0.81) and poor discriminatory ability for detecting elevated LVFP (AUC = 0.54, 95% CI 0.38-0.69). Categorical E/A ratio alone also demonstrated poor discriminatory ability (AUC = 0.53, 95% CI 0.39-0.67), and addition of LA reservoir strain did not significantly improve effectiveness (AUC = 0.58, 95% CI 0.42-0.74, p = 0.56). Average early DSr also demonstrated poor correlation with LVFP (Spearman's rho = -0.19, p = 0.16) and poor discriminatory ability for detecting elevated LVFP (AUC = 0.59, 95% CI 0.44-0.75). Addition of average early DSr to categorical E/A ratio failed to improve effectiveness (AUC = 0.62, 95% CI 0.46-0.77 vs. AUC = 0.54, 95% CI 0.39-0.69, p = 0.38). CONCLUSIONS: In our sample, LA reservoir strain and DSr do not accurately predict diastolic filling pressure. Further research is required before LA strain and early DSr can be routinely used in clinical practice to assess filling pressure in patients with MAC.

Insights Into the Standard Echocardiographic Views From Multimodality Imaging: Ventricles, Pericardium, Valves, and Atria.

The widespread use of cardiac computed tomography and cardiac magnetic resonance imaging in patients undergoing echocardiography presents an opportunity to correlate the images side by side. Accordingly, the aim of this report is to review aspects of the standard echocardiographic examination alongside similarly oriented images from the two tomographic imaging modalities. It is hoped that this exercise will enhance understanding of the structures depicted by echocardiography as they relate to other structures in the thorax. In addition to reviewing basic cardiac anatomy, the authors take advantage of these correlations with computed tomography and cardiac magnetic resonance imaging to better understand the issue of foreshortening, a common pitfall in transthoracic echocardiography. The authors also highlight an important role that three-dimensional echocardiography can potentially play in the future, especially as advances in image processing permit higher fidelity multiplanar reconstruction images.

Insight into different phenotypic presentations of heart failure with preserved ejection fraction.

Heart failure (HF) with preserved ejection fraction (HFpEF) accounts for half of all HF diagnoses, and its prevalence is increasing at an alarming rate. Lately, it has been recognized as a clinical syndrome due to diverse underlying etiology and pathophysiological mechanisms. The classic echocardiographic features of HFpEF have been well described as preserved ejection fraction (≥50%), left ventricular hypertrophy, and left atrial enlargement. However, echocardiography can play a key role in identifying the principal underlying mechanism responsible for HFpEF in the individual patient. The recognition of different phenotypic presentations of HFpEF (infiltrative, metabolic, genetic, and inflammatory) can assist the clinician in tailoring the appropriate management, and offer prognostic information. The goal of this review is to highlight several key phenotypes of HFpEF and illustrate the classic clinical scenario and echocardiographic features of each phenotype with real patient cases.

Serial echocardiography for valve dysfunction and aortic dilation in bicuspid aortic valves.

BACKGROUND AND AIMS: Complications of bicuspid aortic valve commonly include aortic stenosis, aortic regurgitation, and ascending aortic dilation. The progression of these lesions is not well described. MATERIALS AND METHODS: We reviewed 249 bicuspid aortic valve patients with at least two echocardiograms from 2006 to 2016. Valve morphology (right-left or right-noncoronary cusp fusion) was confirmed by visual inspection, and aortic stenosis and regurgitation were quantified according to current guidelines; the ascending aorta was measured at end-systole 2-3 cm above the sinotubular junction. Annualized progression of stenosis, regurgitation, and aortic dilation from first to most recent echocardiogram were compared between right-left and right-nonfused valves using multivariable logistic regression to adjust for baseline differences in groups. RESULTS: Among 249 bicuspid aortic valve patients (mean age 47.6 ± 13.5 years, 66.3% male), 75.9% had right-left cusp fusion. At baseline, aortic stenosis was absent or mild in 80.3%; aortic regurgitation was absent or mild in 80.7%; and aortic diameters were 35.0 ± 5.7 mm (sinuses of Valsalva) and 37.4 ± 6.2 mm (ascending). Mean annualized decrease in aortic valve area was 0.07 cm2 /year, with 30% of bicuspid aortic valve patients progressing ≥0.1 cm2 /year. Aortic regurgitation progressed ≥1 grade in 37 patients. Mean annualized increase in ascending aorta diameter was 0.36 mm/year in right-left and 0.65 mm/year in right-nonbicuspid valves. CONCLUSIONS: In this serial echocardiographic study of bicuspid aortic valve patients, cusp orientation was not associated with progression of valve dysfunction. Right-noncoronary cusp fusion was associated with ascending aortic diameter progression.

COVID-19 resulting in bilateral pulmonary emboli and a right ventricular thrombus: association or causation? A case report.

BACKGROUND: SARS-CoV-2 is a novel viral illness originating out of Wuhan China in late 2019. This global pandemic has infected nearly 3 million people and accounted for 200 000 deaths worldwide, with those numbers still climbing. CASE SUMMARY: We present a 54-year-old patient who developed respiratory failure requiring endotracheal intubation from her infection with SARS-CoV-2. This patient was subsequently found to have a right ventricular thrombus and bilateral pulmonary emboli, likely contributing to her respiratory status. On the 14th day of hospitalization, the patient was successfully extubated, and 5 days later was discharged to the rehabilitation unit. DISCUSSION: SARS-CoV-2 presents primarily with pulmonary symptoms; however, many patients, particularly those who are severely ill, exhibit adverse events related to hypercoagulability. The exact mechanism explaining this hypercoagulable state has yet to be elucidated, but these thrombotic events have been linked to the increased inflammation caused by SARS-CoV-2. This novel viral illness is still largely misunderstood, but the hypercoagulable state, seen in severely ill patients, appears to play a major role in disease progression and prognosis.

Evaluating a decision tool for diagnosing diastolic dysfunction and estimation of left ventricular filling pressures in the presence of mitral annular calcium.

OBJECTIVES: This study sought to evaluate a decision algorithm for the estimation of left ventricular filling pressure (LVFP) in patients with mitral annular calcification (MAC). BACKGROUND: In a single center study, Abudiab et al evaluated echocardiographic parameters to estimate LVFP in patients with MAC against invasive hemodynamic measurements and developed a decision algorithm which demonstrated high predictive accuracy. METHODS: Retrospectively, 55 patients (mean age 68.5 ± 11.5) with MAC and a left heart catheterization within 24 hours of an echocardiogram were identified. The decision algorithm was applied using echo data to classify patients as having normal or elevated LVFP which was then compared with the invasively obtained LVFP. RESULTS: The algorithm performed poorly at predicting pre-A LVFP as normal or high (P = .182). Accuracy for the algorithm was 0.59 [0.46, 0.72] (mean [95% CI]), sensitivity was 0.45 [0.28, 0.62], specificity was 0.73 [0.54, 0.86], false positive rate was 0.27 [0.14, 0.46], and false negative rate was 0.55 [0.38, 0.72]. E/A ratio, IVRT, and E/e'ratio showed no significant relationship to actual patient LVFP. CONCLUSIONS: The Abudiab et al algorithm failed to demonstrate comparable sensitivity, specificity, and accuracy in our sample. Additional study is necessary to refine this tool prior to more widespread use in clinical practice.

Astro-ecology? Shifting the interdisciplinary collaboration paradigm.

We present a case study whereby ecological research on fallen trees in forest plots was advanced by a collaboration with astronomers working on the vector fields of stars and gas, and we propose a framework by which such novel collaborations can progress.

Alteration of the magnetosphere of the Vela pulsar during a glitch.

As pulsars lose energy, primarily in the form of magnetic dipole radiation, their rotation slows down accordingly. For some pulsars, this spin-down is interrupted by occasional abrupt spin-up events known as glitches 1 . A glitch is hypothesized to be a catastrophic release of pinned vorticity 2 that provides an exchange of angular momentum between the superfluid outer core and the crust. This is manifested by a minute alteration in the rotation rate of the neutron star and its co-rotating magnetosphere, which is revealed by an abrupt change in the timing of observed radio pulses. Measurement of the flux density, polarization and single-pulse arrival times of the glitch with high time resolution may reveal the equation of state of the crustal superfluid, its drag-to-lift ratio and the parameters that describe its friction with the crust 3 . This has not hitherto been possible because glitch events happen unpredictably. Here we report single-pulse radio observations of a glitch in the Vela pulsar, which has a rotation frequency of 11.2 hertz. The glitch was detected on 2016 December 12 at 11:36 universal time, during continuous observations of the pulsar over a period of three years. We detected sudden changes in the pulse shape coincident with the glitch event: one pulse was unusually broad, the next pulse was missing (a 'null') and the following two pulses had unexpectedly low linear polarization. This sequence was followed by a 2.6-second interval during which pulses arrived later than usual, indicating that the glitch affects the magnetosphere.

Analyzing linear spatial features in ecology.

The spatial analysis of dimensionless points (e.g., tree locations on a plot map) is common in ecology, for instance using point-process statistics to detect and compare patterns. However, the treatment of one-dimensional linear features (fiber processes) is rarely attempted. Here we appropriate the methods of vector sums and dot products, used regularly in fields like astrophysics, to analyze a data set of mapped linear features (logs) measured in 12 × 1-ha forest plots. For this demonstrative case study, we ask two deceptively simple questions: do trees tend to fall downhill, and if so, does slope gradient matter? Despite noisy data and many potential confounders, we show clearly that topography (slope direction and steepness) of forest plots does matter to treefall. More generally, these results underscore the value of mathematical methods of physics to problems in the spatial analysis of linear features, and the opportunities that interdisciplinary collaboration provides. This work provides scope for a variety of future ecological analyzes of fiber processes in space.

The Arm is Not the Leg: Pathophysiology, Diagnosis, and Management of Upper Extremity Deep Vein Thrombosis.

Upper extremity deep venous thrombosis (UEDVT) involves thrombosis of the deep veins of the arm as they enter the thorax. They are increasing in frequency, largely due to the rising use of central venous catheters and implantable cardiac devices, and represent more than 10% of all DVT cases, Upper extremity deep venous thrombosis has been historically misunderstood when compared to lower extremity deep vein thrombosis (LEDVT). Their associated disease states may carry devastating complications, with mortality rates often higher than that of LEDVT. Thus, education on recognition, classification and management is critical to avoid long-term sequelae and mortality from UEDVT. [Full article available at http://rimed.org/rimedicaljournal-2017-05.asp].

Do state medical board applications violate the americans with disabilities act?

PURPOSE: To determine whether medical licensing board application questions about the mental or physical health or substance use history of the applicant violate the Americans with Disabilities Act (ADA) of 1990. METHOD: Content analysis of 51 allopathic licensing applications (50 states and District of Columbia) was performed at the University of Medicine and Dentistry of New Jersey-New Jersey Medical School in 2005. Questions referencing physical or mental health or substance use were identified by a team of physicians and reviewed and categorized based on the ADA and appropriate case law by legal counsel. RESULTS: Of the 51 applications reviewed, 49 (96%) contained questions pertaining to the physical or mental health or substance use history of the applicant. Thirty-four of the 49 (69%) state medical licensing applications contained at least one "likely impermissible" or "impermissible" item based on the ADA and appropriate case law. CONCLUSIONS: Most state medical licensing applications contain questions that ask about the physical or mental health and substance use of physician applicants. Many licensing applications appear to be in violation of the ADA, even 19 years after enactment of the regulation. These questions do not elicit responses by which professional competence can be judged. The presence of these questions on licensing applications may cause physicians to avoid or delay treatment of personal illness.