Echocardiographic assessment of radial right ventricular function in heart transplant recipients.

AIMS: Right ventricular (RV) allograft dysfunction is present in half of all heart transplant (HT) recipients. Non-invasive assessment of RV function in the setting of rejection is not well described. We outline an echocardiographic technique, short-axis fractional area change (SAXFAC), to evaluate RV function in the HT population and correlate this with the grade of pathologic rejection. METHODS AND RESULTS: We retrospectively reviewed the electronic medical records of 110 people who received a HT between 1 January 2015 and 29 February 2020 and had no evidence of rejection. One hundred eighty-two transthoracic echocardiograms (TTEs) completed up to 1 year from the date of transplantation were analysed for the target acoustic window, the parasternal mid-ventricular short-axis view. Sixty-one TTEs from 23 healthy transplants were deemed appropriate for SAXFAC determination. Thirty-three organ recipients with at least grade 1R allograft rejection were also identified, and their TTEs screened for SAXFAC analysis. Two expert readers independently calculated SAXFAC as follows: RV end-diastolic area minus end-systolic area divided by end-diastolic area. Using commercially available software (Epsilon, Ann Arbor, Michigan), we quantified RV radial strain, longitudinal strain, and apical fractional area change (FAC). Twenty-eight transplant recipients with grade 0R or 1R rejection and nine patients with clinically significant rejection completed the study analysis. SAXFAC demonstrated significant variability in the entire population with an inverse relationship to severity of allograft rejection (P ≤ 0.01). Radial strain and FAC were also associated with clinically significant rejection (P ≤ 0.01). CONCLUSIONS: Short-axis fractional area change is a simple two-dimensional technique to assess RV function in HT recipients and showed no significant inter-observer variability. In our small, single-centre, retrospective case series, lower SAXFAC values were associated with clinically significant allograft rejection. The small sample size and infrequent occurrence of rejection make our observations hypothesis-generating only. We advocate dedicated RV SAXFAC imaging planes be included when assessing allograft function.

Rare and Complex Case Mimics Acute Myocardial Infarction: The Importance of Multimodality Imaging.

We report a rare and complex case of cardiac sarcoidosis in a patient presenting with ventricular tachycardia. Multimodality imaging, along with clinical and histological examination, was essential in establishing the diagnosis of cardiac sarcoidosis. (Level of Difficulty: Beginner.).

Detection of intracranial hematomas in the emergency department using near infrared spectroscopy.

Hypothesis: Traumatic brain injury (TBI) is one of the most important causes of morbidity and mortality in our society. The development of near infrared technology for the detection of intracranial hematomas may assist earlier diagnosis of TBI. This in turn may enable earlier targeted treatments minimizing the harm and subsequent social and economic effects of TBI. Methods: A handheld, noninvasive Near Infrared Spectroscopy device, Infrascanner 2000, (Infrascan Inc., Philadelphia, PA, USA) was used in a major trauma center to screen for traumatic intracranial hematomas. The Infrascanner was used successfully in 205 patients on their arrival in the emergency department prior to CT head. Results: In the whole cohort, sensitivity was 75%, specificity was 50.43%, with negative predictive value 72.84%, and positive predictive value 53.23%. In 45 patients, where the volume of blood was >3.5mL, the sensitivity was 89.36%, specificity 48.73% with negative predictive value 93.9% and positive predictive value 34.15%. Conclusions: The Infrascanner has a relatively high specificity and negative predictive value; therefore, it could in association with the Neurological examination, help in the triage of the trauma patient with potential brain injury. Further investigation is necessary to determine the use of Infrascanner 2000 as a diagnostic method in TBI.

A tetrameric perylene diimide non-fullerene acceptor via unprecedented direct (hetero)arylation cross-coupling reactions.

This study reports on the synthesis of an indancenodithiophene perylene diimide tetramer via unique direct (hetero)arylation reactivity. The thiophene based core structure is shown to be easily functionalized with four perylene diimides at the four active C-H positions. This new reactivity provides a simple synthetic pathway towards tetrameric perylene diimides which have emerged as one of the best classes of electron acceptors for organic solar cells.

Correction: An unsymmetrical non-fullerene acceptor: synthesis via direct heteroarylation, self-assembly, and utility as a low energy absorber in organic photovoltaic cells.

Correction for 'An unsymmetrical non-fullerene acceptor: synthesis via direct heteroarylation, self-assembly, and utility as a low energy absorber in organic photovoltaic cells' by Abby-Jo Payne et al., Chem. Commun., 2017, 53, 10168-10171.

An unsymmetrical non-fullerene acceptor: synthesis via direct heteroarylation, self-assembly, and utility as a low energy absorber in organic photovoltaic cells.

This study reports on the design and synthesis of an unsymmetrical π-conjugated organic molecule composed of perylene diimide, thienyl diketopyrrolopyrrole, and indoloquinoxaline pieced together using direct heteroarylation. This material demonstrates unprecedented response in the thin-film upon post-deposition solvent vapor annealing, resulting in dramatic red-shifts in optical absorption. Such changes were utilized to enhance photocurrent generation in P3HT based organic solar cells.

Optimized synthesis of π-extended squaraine dyes relevant to organic electronics by direct (hetero)arylation and Sonogashira coupling reactions.

This study reports on the synthesis and characterization of four molecular π-extended squaraine compounds relevant to the field of organic electronics. The compounds each consist of a bis-indole squaraine core end-capped with indoloquinoxaline units employing three different bridging units, namely thiophene, thiazole, and acetylene. Compound 10 bears a thiophene bridge, 11 consists of a thiophene bridge and fluorinated indoloquinoxaline terminal units, and compounds 12 and 13 are bridged by thiazole and acetylene, respectively. The final compounds are constructed using the atom economical direct (hetero)arylation or the classic Sonogashira carbon-carbon bond formation protocols. Each carbon-carbon bond forming reaction employing thiophene bridges (i.e. synthesis of compounds 10 and 11) has been optimized using the stable and reusable silica supported Pd catalyst, SiliaCat® DPP-Pd, streamlining the synthetic procedure. While compounds 12 and 13 were also accessible using the SiliaCat® DPP-Pd catalyst, the use of Herrmann-Beller and Pd(PPh3)4 catalysts, respectively, lead to improved isolated yields of the final materials. Compounds 10-13 were characterized by thermal gravimetric analysis, cyclic voltammetry, optical absorption spectroscopy, photoluminescence spectroscopy, and each structure was analysed using density functional theory. All compounds exhibit high thermal stability and good solubility in common organic solvents, including in the greener alternative 2-methyl tetrahydrofuran. The reported compounds display stable ambipolar redox behaviour, furthermore, we have demonstrated that the frontier molecular energy levels can be effectively tuned by changing the bridging unit as predicted by density functional theory. Most striking is the drastic optical absorption profile changes observed from this class of materials upon post-deposition film annealing, suggesting molecular rearrangement in the solid-state. The induced changes and fine structure observed upon post-deposition annealing is unique to these π-extended squaraines with nothing like it reported in the literature for related squaraine based materials.

Synthesis and structure-property relationships of phthalimide and naphthalimide based organic π-conjugated small molecules.

Five organic π-conjugated small molecules with bithiophene-phthalimide backbones bearing alkyl chains of different symmetry, length and branching character were synthesized using optimized microwave and direct heteroarylation protocols. The chosen alkyl chains were 1-ethylpropyl, 1-methylbutyl, pentyl, hexyl and octyl. A sixth compound was also synthesized replacing the phthalimide terminal units with octylnaphthalimide for additional scope. Through the thorough analysis of both thermal and optical properties and the investigation of self-assembly tendencies by single crystal X-ray diffraction and variable angle spectroscopic ellipsometry it is evident that alkyl side chains and building block size influence many facets of material properties. Within this class of materials the 1-ethylpropyl derivative exhibited the most unique behaviour.

An electron-deficient small molecule accessible from sustainable synthesis and building blocks for use as a fullerene alternative in organic photovoltaics.

An electron-deficient small molecule accessible from sustainable isoindigo and phthalimide building blocks was synthesized via optimized synthetic procedures that incorporate microwave-assisted synthesis and a heterogeneous catalyst for Suzuki coupling, and direct heteroarylation carbon-carbon bond forming reactions. The material was designed as a non-fullerene acceptor with the help of DFT calculations and characterized by optical, electronic, and thermal analysis. Further investigation of the material revealed a differing solid-state morphology with the use of three well-known processing conditions: thermal annealing, solvent vapor annealing and small volume fractions of 1,8-diiodooctane (DIO) additive. These unique morphologies persist in the active layer blends and have demonstrated a distinct influence on device performance. Organic photovoltaic-bulk heterojunction (OPV-BHJ) devices show an inherently high open circuit voltage (Voc ) with the best power conversion efficiency (PCE) cells reaching 1.0 V with 0.4 v/v % DIO as a processing additive.