Novel Use of Tamoxifen to Reduce Recurrent Gastrointestinal Bleeding in Patients with Left Ventricular Assist Devices.

Gastrointestinal bleeding (GIB) is a frequent complication in patients with continuous-flow left ventricular assist devices (LVAD). We retrospectively evaluated eight patients implanted with a HeartWare LVAD between July 2017 and June 2020 who experienced at least one episode of GIB and were started on tamoxifen 20 mg once daily for secondary prevention. Tamoxifen was associated with a significant decrease in major GIB from a median of 3 (IQR 1.4-7) events/patient-year pre-tamoxifen initiation to 0 (IQR 0-0.9) events/patient-year post-tamoxifen initiation (p = 0.02). Transfusion of packed red blood cells also decreased from 16.8 (IQR 9.9-30.6) units/patient-year pre-tamoxifen initiation to 1.5 (IQR 0-7.5) units/patient-year post-tamoxifen (p = 0.04). Tamoxifen was well tolerated and no thromboembolic complications were observed. This small cohort study suggests that tamoxifen is associated with reduced GIB and transfusion requirements, with no apparent increase in thrombotic risk. A larger, randomized study is warranted to confirm the results of this exploratory analysis. Graphical abstract.

Should we overcome the resistance to bioelectrical impedance in heart failure?

INTRODUCTION: Heart failure is associated with increased neurohormonal activation that results in changes in body composition including volume overload and the loss of skeletal muscle, body fat, and bone density. Bioelectrical impedance measures body composition based on the conduction of electrical current through body fluids. AREAS COVERED: The PubMed and Scopus databases were reviewed up to the third week of June 2020. Cross-sectional studies, retrospective observational studies, prospective observational studies, and randomized controlled trials have examined numerous bioelectrical impedance monitoring strategies to guide the diagnosis, prognosis, and treatment of heart failure. These monitoring strategies include intrathoracic impedance, lung impedance, bioelectrical impedance vector analysis, leg bioelectrical impedance, and thoracic bioreactance. EXPERT COMMENTARY: Based on the current evidence, more studies are needed to validate bioelectrical impedance in heart failure. Lung impedance appears to be useful for guiding heart failure treatment in patients with ST-elevation myocardial infarction and improving outcomes in outpatients with heart failure. Furthermore, bioelectrical impedance has potential as a noninvasive, quantitative heart failure variable for population-based research.

Sarcoidosis-associated hypercalcemia potentiating calcific uremic arteriolopathy in a patient with a left ventricular assist device.

Calcific uremic arteriolopathy is a rare, life-threatening syndrome of vascular calcification characterized by occlusion of microvessels that results in extremely painful skin necrosis. We present a case of sarcoidosis-associated hypercalcemia potentiating calcific uremic arteriolopathy in a patient with a left ventricular assist device. The patient's calcific uremic arteriolopathy was successfully treated with sodium thiosulfate. Clinicians should be vigilant in diagnosing calcific uremic arteriolopathy early since it is especially life-threatening in patients with multiple risk factors.

Aortic Root Abscess with Aorta to Right Atrium Fistula due to Vancomycin-Intermediate Staphylococcus aureus (VISA).

We present a case of root abscess with aorta to right atrium fistula due to vancomycin-intermediate Staphylococcus aureus (VISA) after limb amputation and cardiac surgery. Patient underwent redo aortic valve replacement, patch repair of aorta to right atrial fistula, and tricuspid valve repair with a ring. Fistula formation is a rare complication of prosthetic valve endocarditis (PVE). This is the first case to discuss aortocavitary fistula (ACF) formation due to VISA. Transesophageal echocardiogram (TEE) is the preferred imaging modality to diagnose ACF.

A review for clinicians: Prostate cancer and the antineoplastic properties of metformin.

OBJECTIVES: Metformin has numerous antineoplastic effects including an AMP-activated protein kinase-dependent mechanism, AMP-activated protein kinase-independent mechanisms, alteration of insulin and insulin-like growth factor signaling pathways, and suppression of androgen signaling pathways that trigger prostate cancer growth and proliferation. In contrast to other malignancies that are associated with increased incidence among patients with obesity and type II diabetes mellitus (T2DM), epidemiological studies suggest that obesity and T2DM may impart a protective effect on prostate cancer incidence by creating a set of metabolic conditions that lower androgen levels. METHODS AND MATERIALS: The PubMed and Web of Science databases were searched using the terms "prostate cancer," "metformin," "antineoplastic," "antitumorigenic," and "diabetes" up to the first week of August 2016. Articles regarding metformin's antineoplastic properties on prostate cancer were reviewed. RESULTS: Treating T2DM with metformin may reverse the metabolic conditions that suppress androgen levels, thereby enabling higher levels of androgens to stimulate prostate growth, proliferation, and tumorigenesis. Thus, the antineoplastic properties of metformin may not be appreciable in the early stages of prostate cancer development because metformin corrects for the metabolic conditions of T2DM that impart a protective effect on prostate cancer. These findings, although inconclusive, do not support the use of metformin as a preventive agent for prostate cancer. However, the future appears bright for metformin as either a monotherapy or an adjunct to androgen deprivation therapy, external-beam radiation therapy, prostatectomy, or chemotherapy. Support for this includes meta-analyses that suggest a mortality benefit to patients with prostate cancer on metformin, a clinical trial that demonstrates metformin leads to significant improvement in metabolic syndrome parameters for patients with prostate cancer on androgen deprivation therapy, and a clinical trial that shows metformin has modest activity in the treatment of some patients with asymptomatic or minimally symptomatic metastatic castration-resistant prostate cancer. CONCLUSIONS: This review summarizes the literature regarding the antineoplastic mechanisms, clinical implications, and future trajectory of clinical research for metformin in prostate cancer.