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Introduction: Sleep deprivation impacts clinical performance. However, literature is conflicting, with insufficient focus on patient outcomes. The aim of this study was to assess if patient satisfaction and prescription errors in outpatient clinics were adversely affected when consulting post-call versus non-post-call registrars. Methods: This prospective, quantitative study was set in a large teaching hospital in Singapore. Between November 2015 and February 2016, patients from clinics run by a registrar after 24-hour shift were recruited to post-call group. Patients from non-post-call clinics run by the same registrar were controls. Outcome measures were patient satisfaction, using 5-item 4-point Likert scale questionnaire, and prescribing error rate, defined as number of errors over number of orders. Differences were analysed using chi-squared test. Results: 103 of 106 (97%) patients in 9 post-call clinics and 93 of 105 (90%) patients in 9 non-post-call clinics were recruited. Questionnaire completion rate was 99%. 536 and 526 prescriptions were ordered in post-call and non-post-call groups, respectively. Percentage of top-box responses (greatest satisfaction) was higher in post-call group overall (79.3% versus 62.4%, p

While brachial mean blood pressure (MBP) and left ventricular mass (LVM) measured from CTCA are the two CFD simulation input parameters, their effects on noninvasive fractional flow reserve (FFRB) have not been systematically investigated. We demonstrate that inaccurate MBP and LVM inputs differing from patient-specific values could result in misclassification of borderline ischemic lesions. This is important in the clinical application of noninvasive FFR in coronary artery disease diagnosis.

We compared real-world clinical outcomes of patients receiving intravascular lithotripsy (IVL) versus rotational atherectomy (RA) for heavily calcified coronary lesions.Fifty-three patients who received IVL from January 2017 to July 2020 were retrospectively compared to 271 patients who received RA from January 2017 to December 2018. Primary endpoints were in-hospital and 30-day major adverse cardiovascular events (MACE).IVL patients had a higher prevalence of acute coronary syndrome (56.6% vs 24.4, p0.001), multivessel disease (96.2% vs 73.3%, p0.001) and emergency procedures (17.0% vs 2.2%, p0.001) compared to RA. In-hospital MACE (11.3% vs 5.9%, p=0.152), MI (7.5% vs 3.3%, p=0.152), and mortality (5.7% vs 3.0%, p=0.319) were not statistically significant. 30-day MACE was higher in the IVL cohort vs RA (17.0% vs 7.4%, p=0.035). Propensity score adjusted regression using IVL was also performed on in-hospital MACE (odds ratio [OR], 1.677; 95% confidence interval [CI], 0.588-4.779) and 30-day MACE (OR, 1.910; 95% CI, 0.774-4.718).These findings represent our initial IVL experience in a high-risk, real-world cohort. Although the event rate in the IVL arm was numerically higher compared to RA, the small numbers and retrospective nature of this study preclude definitive conclusions. These clinical outcomes are likely to improve with greater experience and better case selection, allowing IVL to effectively treat complex calcified coronary lesions.

In-stent restenosis (ISR) is an important cause of drug-eluting stent (DES) failure and target vessel revascularisation. In this study we aimed to evaluate differences between early and late-presenting restenosis in second-generation DES using optical coherence tomography (OCT).Overall, 171 cases of second-generation DES ISR with a follow-up OCT minimum lumen area3.0 mm2 were included: 33.3% of patients (n=57) had early ISR, and 66.7% (n=114) had late ISR (duration from stent implantation1 year). Minimum stent area (MSA)4.0 mm2, neointimal thickness100 µm, and heterogeneous neointimal hyperplasia (NIH) were more prevalent in early ISR, whereas NIH with neoatherosclerosis trended towards being more frequent for late ISR (28.9% vs. 15.8%, p=0.06). Multivariable analysis revealed that duration from implantation2 years, absence of statin use, and NIH50% were independent predictors for neoatherosclerosis (all p0.05).OCT morphological characteristics of second-generation DES ISR differ between early and late presentation. Early ISR was associated with MSA4.0 mm2, while neoatherosclerosis contributed more commonly to late ISR.

This article was migrated. The article was not marked as recommended. The 2019 novel coronavirus disease (COVID-19) spreads outside China rapidly and became a global pandemic. Recognising its severity and with experiences from the Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) outbreak in 2003, the Singapore government promptly and decisively implemented measures to contain the disease. Many of them have direct effects on our healthcare workers (HCW), and our graduate medical education, which is modelled after the US residency training system, has invariably been impacted to a large degree. Strategies aimed at minimising unnecessary contact between HCW, and directives to step up on human resources as healthcare institutions prepare to cope with a disease outbreak called for modifications to residents' training routine. Residents are affected by curtailment of leave and reallocation of manpower to meet the demands at various frontlines and have to cope with significant physical and emotional stress from anxiety and even pessimism as the situation unfolds with unpredictability. Nevertheless, the pandemic also presents a rare opportunity for residents to learn about healthcare in an international and interdisciplinary context, and develop qualities like resilience, adaptability and solidarity in the face of a medical crisis.

Background/purpose We sought to evaluate the morphological characteristics of nonobstructive coronary lesions in patients with ischemic symptoms and/or signs. Materials/methods We used optical coherence tomography (OCT) to assess the presumed culprit lesion in 142 patients with suspected coronary artery disease in whom coronary angiography showed no lesion with a diameter stenosis ≥50%. Patients with a clinical diagnosis of acute coronary syndrome (ACS, n = 31, including 2 ST-elevation myocardial infarction, 9 non-ST-elevation myocardial infarction, and 20 unstable angina pectoris) were compared to those with stable coronary artery disease (CAD) (n = 111) including 79 patients with stable angina and 32 patients with silent ischemia (positive non-invasive stress test only). Results The overall prevalence of thrombus, plaque rupture, intimal laceration, or calcified nodule in the combined groups was 23.2% (33/142) including 15 thrombus, 12 plaque rupture, 9 calcified nodule, and 8 intimal laceration (not mutually exclusive) without differences between ACS and stable CAD patients. Also the prevalence of thin-cap fibroatheroma was not significantly different between ACS and stable patients (12.9% vs 6.3%, p = 0.22). Minimum lumen area (3.1 mm2 [2.3, 4.1] versus 3.2 mm2 [2.4, 4.7], p = 0.7) and area stenosis (49.9% [37.1, 56.4] versus 48.1% [37.8, 55.8], p = 0.9) were similar between ACS and stable CAD patients. Conclusion In patients presenting with ischemic symptoms and/or signs, but angiographically nonobstructive culprit lesions, approximately 25% had abnormal findings by OCT—whether patients presented with acute/unstable or stable CAD.

Background Computed tomography coronary angiography (CTCA) image analysis enables plaque characterization and non-invasive fractional flow reserve (FFR) calculation. We analyzed various parameters derived from CTCA images and evaluated their associations with ischemia. Methods 49 (61 lesions) patients underwent CTCA and invasive FFR. Lesions with diameter stenosis (DS) ≥ 50% were considered obstructive. CTCA image processing incorporating analytical and numerical methods were used to quantify anatomical parameters of lesion length (LL) and minimum lumen area (MLA); plaque characteristic parameters of plaque volume, low attenuation plaque (LAP) volume, dense calcium volume (DCV), normalized plaque volume (NP Vol), plaque burden, eccentricity index and napkin-ring (NR) sign; and hemodynamic parameters of resistance index, stenosis flow reserve (SFR) and FFR B . Ischemia was defined as FFR ≤ 0.8. Results Plaque burden and plaque volume were inversely related to FFR. Multivariable logistic regression analysis identified the best anatomical, plaque and hemodynamic predictors, respectively, as DS (≥50% vs B (≤0.8 vs >0.8; OR: 44.4; 95% CI: 8.8–224.8). AUC increased from 0.70 with DS as the sole predictor to 0.81 after adding NP Vol and NR Sign; further addition of FFR B increased AUC to 0.93. Conclusion Normalized plaque volume, napkin-ring derived from plaque analysis, and FFR B from numerical simulations on CTCA images substantially improved discrimination of ischemic lesions, compared to assessment by DS alone.

One of the fundamental operations in computer vision applications is change detection, in which moving foreground objects are segmented from a static background. A common approach for change detection is the comparison of an image frame with the stored background model using a matching algorithm, a process known as background subtraction. However, such techniques fail in environments with dynamic backgrounds, illumination changes, or shadow and camera jitters. This study focuses on effectively detecting scene changes in complex environments. To this end, we proposed a new colour descriptor named local colour difference pattern (LCDP) that is insusceptible to shadow and is able to capture both colour and texture features at a pixel location. Furthermore, a scene change detection framework was proposed to handle dynamic scenes based on sample consensus that integrates LCDP and a novel spatial model fusion mechanism. Experiments using the CDnet benchmark dataset demonstrated the effectiveness of the proposed approach to change detection in complex environments.

Although reported in bare metal stents (BMS) and first-generation drug-eluting stents (DES), little is known about neoatherosclerosis in second-generation DES. We used optical coherence tomography to evaluate neoatherosclerosis among different stent generations. Overall, 274 in-stent restenosis (ISR) lesions (duration from implantation 56.9 ± 47.2 months) in 274 patients were assessed for the presence of neoatherosclerosis. Neoatherosclerosis was identified in 38.7% of lesions (106/274): 23.0% second-generation DES (38/165), 65.1% first-generation DES (54/83), and 53.8% BMS (14/26). In the neoatherosclerosis cohort (n = 106), more stent underexpansion or fracture/deformation was observed in second-generation DES, whereas thrombus, without plaque rupture, or evagination was more common in first-generation DES. In multivariable analyses, duration from implantation >1 year (OR: 2.44, 95% CI 1.12–5.31; p = 0.03), absence of angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers (OR 1.95, 95% CI 1.10–3.44; p = 0.02) or statins at the time of ISR (OR 3.12, 95% CI 1.42–6.84; p = 0.01), and first-generation vs first-generation DES (OR 5.32, 95% CI 2.82–10.10; p

We sought to examine the relation between various degrees of renal function and coronary plaque morphology by grayscale and virtual histology intravascular ultrasound (IVUS). ADAPT-DES was a prospective, multicenter registry of 8,582 consecutive patients treated using coronary drug-eluting stents with a prespecified grayscale and virtual histology-IVUS substudy. A lesion-level analysis of study participants was performed by comparing IVUS parameters of culprit and nonculprit lesions across tertiles of estimated creatinine clearance (CrCl). Preintervention IVUS imaging of 762 patients identified 898 culprit and 752 nonculprit native coronary artery lesions. Patients in the lowest CrCl tertile were older, more often women, and more often presented with stable angina. Compared with the middle and upper tertiles, the lowest tertile was significantly associated with culprit lesion smaller mean external elastic membrane cross-sectional area (12.9 vs 14.2 mm 3 /mm vs 14.9 mm 3 /mm, p 3 /mm vs 5.8 mm 3 /mm vs 6.1 mm 3 /mm, p = 0.002), and more dense calcium volume (11.5% vs 10.2% vs 9.7%, p = 0.02). Similar trends were found in the nonculprit lesions. Plaque rupture was least common in patients in the lowest tertile. On multivariable analysis, independent predictors of greater dense calcium volume were lower CrCl, hyperlipidemia, female gender, and presentation without ST-segment elevation myocardial infarction. In conclusion, in the present large-scale IVUS study diminishing renal function was associated with increased coronary calcification and decreased coronary vessel and lumen sizes, with a graded response according to the reduction in CrCl. In addition, these patients were more likely to present with stable angina versus patients with normal renal function who were more likely to present with an acute coronary syndrome.

High-definition 60-MHz intravascular ultrasound (IVUS) represents the current state of the art in IVUS imaging, offering superior spatial resolution of

Patient initials or identifier number STK ### Relevant clinical history and physical exam A 67-year-old man has experienced recurrent unstable angina pectoris (Canadian Cardiovascular Society angina class IV) in the last six months. He had a 30-year history of smoking twenty cigarettes per

Endothelial dysfunction is associated with traditional and systemic lupus erythematosus (SLE)-specific risk factors, and early data suggest reversibility of endothelial dysfunction with therapy. The clinical relevance of endothelial function assessment has been limited by the lack of studies, demonstrating its prognostic significance and impact on early myocardial function. Therefore, we aimed to determine the association between endothelial and myocardial diastolic function in SLE women. Women with SLE and no coronary artery disease were prospectively recruited and underwent radionuclide myocardial perfusion imaging (MPI) (Jetstream, Philips, the Netherlands) to exclude subclinical myocardial ischemia. Cardiac and vascular functions were assessed in all patients (Alpha 10, Aloka, Tokyo). Diastolic function was assessed using pulse wave early (E) and late mitral blood inflow and myocardial tissue Doppler (mean of medial and lateral annulus e′) velocities. Endothelial function was measured using brachial artery flow-mediated vasodilatation (FMD%). Univariate and multivariate linear regressions were used to assess the association between FMD% and myocardial diastolic function, adjusting for potential confounders. Thirty-eight patients without detectable myocardial ischemia on MPI were studied (mean age 44 ± 10 years; mean disease duration 14 ± 6 years). About 61 % of patients had normal diastolic function (E/e′ ≤ 8), and 5 % of patients had definite diastolic dysfunction with E/e′ > 13 (mean 7.1 ± 2.9). FMD% was associated with E/e′ (regression coefficient β = −0.35; 95 % CI −0.62 to −0.08; p = 0.01) independent of systolic blood pressure, age, and SLICC/ACR Damage Index.

Mechanisms and patterns of in-stent restenosis (ISR) comparing bare metal stents (BMS) and 1st and 2nd generation drug-eluting stent (DES) as evaluated by optical coherence tomography (OCT) have not been well delineated. OCT evaluation of ISR (minimum lumen area