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Background: In patients with end-stage heart failure, durable Left Ventricular Assist Devices (LVADs) can be used as a bridge to transplant or destination therapy. LVADs have been shown to improve survival for patients with heart failure (HF). HF is associated with electrolyte abnormalities and the development of sustained arrhythmias. However, data on the influence of arrhythmias and electrolyte imbalances on inpatient outcomes in LVAD patients are lacking. Furthermore, previous works assessing inpatient outcomes focused mainly on the role of chronic comorbidities in those outcomes. Methods: In this cross-sectional study, we used discharge data from the National Inpatient Sample from 2019 to 2020 to assess the influence of acute arrhythmias on inpatient mortality in patients with LVADs. We also investigated the relationship between acute medical conditions and mortality. Results: There were 9418 (not survey-adjusted) hospitalizations with LVAD, among which 2539 (27%) died during the hospitalization. Univariate analysis of arrhythmias showed that ventricular arrhythmias (VAs)—ventricular fibrillation/flutter and ventricular tachycardia—as well as complete heart block were associated with significantly higher odds of mortality. Follow-up multivariable logistic analysis showed that these arrhythmias retain their increased association with death. Hyperkalemia and acidosis had increased adjusted odds of death (1.54 (95% confidence interval: 1.28–1.85) (p < 0.001) and 2.44 (CI: 2.14–2.77) (p < 0.001), respectively). Conclusions: VAs, complete heart block, hyperkalemia, and acidosis were associated with increased odds of all-cause mortality. Females had higher odds of inpatient mortality. These findings suggest that electrolyte management, maintenance of optimal acid–base balance, and interventions to treat sustained ventricular arrhythmias may be suitable therapeutic targets to reduce mortality in hospitalized patients with LVADs.

The concept of variable stoichiometry cocrystallization is explored in halogen-bonded systems. Three novel cocrystals of 1,4-diiodotetrafluorobenzene and 3-nitropyridine with molar ratios of 1:1, 2:1, and 1:2, respectively, are prepared by slow evaporation methods. Single-crystal X-ray diffraction analysis reveals key differences between each of the nominally similar cocrystals. For instance, the 1:1 cocrystal crystallizes in the [P2.sub.1]/n space group and features a single chemically and crystallographically unique halogen bond between iodine and the pyridyl nitrogen. The 2:1 cocrystal crystallizes in the P1 space group and features a halogen bond between iodine and one of the nitro oxygens in addition to an iodine--nitrogen halogen bond. The 1:2 cocrystal crystallizes with a large unit cell (V = 9896 [A.sup.3]) in the Cc space group and features 10 crystallographically distinct iodine-nitrogen halogen bonds. Powder X-ray diffraction experiments carried out on the 1:1 and 2:1 cocrystals confirm that gentle grinding does not alter the crystal forms. [.sup.1]H [right arrow] [.sup.13]C and [.sup.19]F [right arrow] [.sup.13]C cross-polarization magic angle spinning (CP/MAS) NMR experiments performed on powdered samples of the 1:1 and 2:1 cocrystals are used as spectral editing tools to select for either the halogen bond acceptor or donor, respectively. Carbon-13 chemical shifts in the cocrystals are shown to change only very subtly relative to pure solid 1,4-diiodotetrafluorobenzene, but the shift of the carbon directly bonded to iodine nevertheless increases, consistent with halogen bond formation (e.g., a shift of +1.6 ppm for the 2:1 cocrystal). This work contributes new examples to the field of variable stoichiometry cocrystal engineering with halogen bonds. Key words: solid-state NMR, X-ray diffraction, halogen bond, cocrystal, polymorphism, stoichiometry, stoichiomorphism. Nous avons etudie le concept de cocristallisation a stoechiometrie variable dans des systemes a liaison halogene. Nous avons prepare par evaporation lente trois nouveaux cocristaux de 1,4-diiodotetrafluorobenzene et de 3-nitropyridine avec des rapports molaires de 1:1, de 2:1 et de 1:2, respectivement. L&apos;analyse par diffraction des rayons X sur monocristal revele des differences importantes entre les cocristaux theoriquement similaires. Par exemple, le cocrystal 1:1 cristallise selon le groupe d&apos;espace [P2.sub.1]/n et presente une seule liaison halogene, sur les plans chimique et cristallographique, entre l&apos;iode et l&apos;azote du groupe pyridyle. Le cocrystal 2:1 cristallise selon le groupe d&apos;espace P1 et presente une liaison halogene entre l&apos;iode et l&apos;un des oxygenes du groupe nitro, en plus de la liaison halogene iode-azote. Le cocristal 1:2 cristallise en formant une grande cellule unitaire (V = 9896 [A.sup.3]) selon le groupe d&apos;espace Cc et presente 10 liaisons halogene iode-azote distinctes sur le plan cristallographique. Des experiences de diffraction des rayons X sur poudre realisees sur les cocristaux 1:1 et 2:1 confirment qu&apos;un broyage leger ne modifie pas les formes cristallines. Nous avons utilise des experiences de RMN [.sup.1]H [right arrow] [.sup.13]C et [.sup.19]F [right arrow] [.sup.13]C a polarisation croisee en rotation a l&apos;angle magique (CP/MAS, cross-polarization/magic angle spinning), realisees sur des echantillons de cocristaux 1:1 et 2:1 sous forme de poudre, comme outils d&apos;edition spectrale pour selectionner l&apos;accepteur ou le donneur de liaison halogene, respectivement. Les deplacements chimiques du carbone-13 dans les cocris-taux ne changent que de facon tres subtile par rapport au 1,4-diiodotetrafluorobenzene solide pur, mais le deplacement du carbone directement lie a l&apos;iode augmente neanmoins, ce qui concorde avec la formation de liaisons halogene (p. ex., un deplacement de +1,6 ppm dans le cas du cocrystal 2:1). Ces travaux apportent de nouveaux exemples au domaine de l&apos;ingenierie des cocristaux a stoechiometrie variable comportant des liaisons halogene. [Traduit par la Redaction] Mots-cles : RMN a l&apos;etat solide, diffraction des rayons X, liaison halogene, cocristal, polymorphisme, stoechiometrie, stoechiomorphisme., Introduction Molecular and ionic solids can adopt a range of forms depending on how they are prepared. (1,2) Such forms include pure crystalline or amorphous phases, hydrates, or solvates. In [...]

Lithium salts continue to find pharmaceutical applications, particularly as psychiatric medications. As with any active pharmaceutical ingredient, structural polymorphism is an important concern for lithium-based medications that can influence solubility and other physicochemical properties. Here we report a 13C, 1H, and 7Li magic-angle spinning solid-state nuclear magnetic resonance (MAS SSNMR) study of two 1:1 polymorphic ionic cocrystals of lithium 4-methoxybenzoate and L-proline (L4MPRO(α) and L4MPRO(β)). One-dimensional 13C cross-polarization MAS and two-dimensional heteronuclear correlation NMR spectra hint at differential mobilities of the proline and benzoate moieties for the two polymorphs. Five key resonances differ in 13C chemical shift by more than 1 ppm between the two polymorphs, clearly distinguishing between them. Gauge-including projector-augmented-wave density functional theory calculations of 13C and 1H magnetic shielding constants correlate strongly with the experimental chemical shifts for both polymorphs. R2 and root-mean-square deviation metrics are shown to be insufficient in the case of 13C, but sufficient in the case of 1H, for differentiating between the polymorphs. 7Li satellite-transition MAS NMR of both polymorphs are identical, as are the computed lithium magnetic shielding constants, demonstrating the insensitivity of 7Li NMR to polymorphism in these samples. This work highlights the utility of solid-state NMR spectroscopy for examining ionic salt cocrystals and also highlights some caveats in this regard. [ABSTRACT FROM AUTHOR]

Cerebral artery aneurysms are present in up to 10% of ischemic stroke patients, often within or adjacent to the occluded vessel. In some cases, the approach to intervention may need to be modified based on the size and location of the aneurysm. We describe a 99-year-old female with a known history of cerebral aneurysm who underwent successfully mechanical thrombectomy of a right middle cerebral artery thrombus; an 8-mm aneurysm involving the right M1 bifurcation was identified only on post-procedural digital subtraction angiography. In addition, we discuss strategies to reduce the risk of iatrogenic aneurysm rupture in the setting of endovascular thrombectomy.

Macrocycle formation that relies upon trans metal coordination of appropriately placed pyridine ligands within an arylene ethynylene construct provides rapid and reliable access to molecular rotators encapsulated within macrocyclic stators. Showing no significant close contacts to the central rotators, X‐ray crystallography of AgI‐coordinated macrocycles provides plausibility for unobstructed rotation or wobbling of rotators within the central cavity. Solid‐state 13C NMR of PdII‐coordinated macrocycles supports the notion of unobstructed movement of simple arenes in the crystal lattice. Solution 1H NMR studies indicate complete and immediate macrocycle formation upon the introduction of PdII to the pyridyl‐based ligand at room temperature. Moreover, the formed macrocycle is stable in solution; a lack of significant changes in the 1H NMR spectrum upon cooling to −50 °C is consistent with the absence of dynamic behavior. The synthetic route to these macrocycles is expedient and modular, providing access to rather complex constructs in four simple steps involving Sonogashira coupling and deprotection reactions. [ABSTRACT FROM AUTHOR]

The first example of a binary cocrystal, comprised of SnPh3Cl and PPh3, whose components are organized via short and directional tetrel bonds (TtB) between tin and phosphorus, is described. DFT elucidates, for the first time, the factors influencing the strength of TtBs involving heavy pnictogens. A CSD survey reveals that such TtBs are also present and determinative in single component molecular systems, highlighting their significant potential as tuneable structure-directing elements. [ABSTRACT FROM AUTHOR]

Phenomena such as anticooperativity and competition among non‐covalent bond donors and acceptors are key considerations when exploring the polymorphic and stoichiomorphic landscapes of binary and higher‐order cocrystalline architectures. We describe the preparation of four cocrystals of 1,3,5‐trifluoro‐2,4,6‐triiodobenzene with N‐heterocyclic compounds, namely acridine, 3‐aminopyridine, 4‐methylaminopyridine, and 1,2‐di(4‐pyridyl)ethane. The cocrystals, which are characterized by single‐crystal and powder X‐ray diffraction experiments, all show moderately strong and directional iodine⋅⋅⋅nitrogen halogen bonds with reduced distance parameters ranging from 0.79 to 0.92 and carbon‐iodine⋅⋅⋅nitrogen bond angles ranging from 165.4(3) to 175.31(7)°. The cocrystal comprising 1,3,5‐trifluoro‐2,4,6‐triiodobenzene and acridine provides a relatively rare example where all three halogen bond donor sites form halogen bonds with three acceptor molecules, overcoming an anticooperative effect. This effect manifests itself through the lengthening of non‐halogen‐bonded C−I bonds, weakening their potential to form halogen bonds. The effect is only observed once two halogen bonds have been formed to 1,3,5‐trifluoro‐2,4,6‐triiodobenzene; one such bond does not appear to be adequate. Among the four cocrystals studied, competition between the pyridyl nitrogen atoms and the amine nitrogen atoms suggests that the former are the preferred halogen bond acceptors. Analysis by Hirshfeld fingerprint plots and 13C and 19F magic‐angle spinning solid‐state nuclear magnetic resonance (NMR) spectroscopy provides additional insights into the prevalence of various short contacts in the crystal structures and into the spectral response to halogen‐bond‐induced cocrystallization. [ABSTRACT FROM AUTHOR]

Three novel chalcogen‐bonded cocrystals featuring 3,4‐dicyano‐1,2,5‐selenodiazole (C4N4Se) or 3,4‐dicyano‐1,2,5‐tellurodiazole (C4N4Te) as chalcogen‐bond donors and hydroquinone (C6H6O2), tetraphenylphosphonium chloride (C24H20P+·Cl−) or tetraethylphosphonium chloride (C8H20P+·Cl−) as chalcogen‐bond acceptors have been prepared and characterized by single‐crystal X‐ray diffraction (XRD), powder X‐ray diffraction and 77Se/125Te magic‐angle spinning solid‐state NMR spectroscopy. The single‐crystal XRD results show that the chalcogenodiazole molecules interact with the electron donors through two σ‐holes on each of the chalcogen atoms, which results in highly directional and moderately strong chalcogen bonds. Powder XRD confirms that the crystalline phases are preserved upon moderate grinding of the samples for solid‐state NMR experiments. Measurement of 77Se and 125Te chemical shift tensors via magic‐angle spinning solid‐state NMR spectroscopy confirms the number of magnetically unique chalcogen sites in each asymmetric unit and reveals the impact of chalcogen‐bond formation on the local electronic structure. These NMR data are further assessed in the context of analogous data for a wider range of crystalline chalcogen‐bonded systems. [ABSTRACT FROM AUTHOR]

Halogen bonding to phosphorus atoms remains uncommon, with relatively few examples reported in the literature. Here, the preparation and investigation of the cocrystal bis(dicyclohexylphenylphosphine)(1,6-diiodoperfluorohexane) by X-ray crystallography and solid-state multinuclear magnetic resonance spectroscopy is described. The crystal structure features two crystallographically unique C--I...P halogen bonds [dI...P = 3.090 (5) A, 3.264 (5) A ] and crystallographic disorder of one of the 1,6-diiodoperfluorohexane molecules. The first of these is the shortest and most linear I...P halogen bond reported to date. 13C, 19F, and 31P magic angle spinning solid-state NMR spectra are reported. A 31P chemical shift change of -7.0 p.p.m. in the cocrystal relative to pure dicyclohexylphenylphosphine, consistent with halogen bond formation, is noted. This work establishes iodoperfluoroalkanes as viable halogen bond donors when paired with phosphorus acceptors, and also shows that dicyclohexylphenylphosphine can act as a practical halogen bond acceptor. [ABSTRACT FROM AUTHOR]