COVID-19 and myocardial injury: Targeting elevated biomarkers for potential novel therapies.

Background: The prevalence of COVID-19 as the primary diagnosis among hospitalized patients with myocardial injury has increased during the pandemic and targeting elevated oxidant stress and inflammatory biomarkers may offer a potential role for novel therapies to improve outcomes.

Methods: At a single VA Medical Center from January 1 through December 31, 2021, troponin assays from patients being evaluated in the Emergency Room for consideration of admission were analyzed and peak levels from each patient were considered abnormal if exceeding the Upper Reference Limit (URL). Among admitted patients with an elevated troponin level, ICD-10 diagnoses were categorized, biomarker elevations were recorded, and independent predictors of death in patients with COVID-19 were determined at a median of 6-months following admission.

Surgical Porcine Model of Chronic Myocardial Ischemia Treated by Exosome-laden Collagen Patch and Off-pump Coronary Artery Bypass Graft.

Chronic myocardial ischemia resulting from progressive coronary artery stenosis leads to hibernating myocardium (HIB), defined as myocardium that adapts to reduced oxygen availability by reducing metabolic activity, thereby preventing irreversible cardiomyocyte injury and infarction. This is distinct from myocardial infarction, as HIB has the potential for recovery with revascularization. Patients with significant coronary artery disease (CAD) experience chronic ischemia, which puts them at risk for heart failure and sudden death.

Stem cell-derived exosome patch with coronary artery bypass graft restores cardiac function in chronically ischemic porcine myocardium.

Objective: This study aimed to investigate whether or not the application of a stem cell-derived exosome-laden collagen patch (EXP) during coronary artery bypass grafting (CABG) can recover cardiac function by modulating mitochondrial bioenergetics and myocardial inflammation in hibernating myocardium (HIB), which is defined as myocardium with reduced blood flow and function that retains viability and variable contractile reserve.

Methods: In vitro methods involved exposing H9C2 cardiomyocytes to hypoxia followed by normoxic coculture with porcine mesenchymal stem cells. Mitochondrial respiration was measured using Seahorse assay.

An Adjuvant Stem Cell Patch with Coronary Artery Bypass Graft Surgery Improves Diastolic Recovery in Porcine Hibernating Myocardium.

Diastolic dysfunction persists despite coronary artery bypass graft surgery (CABG) in patients with hibernating myocardium (HIB). We studied whether the adjunctive use of a mesenchymal stem cells (MSCs) patch during CABG improves diastolic function by reducing inflammation and fibrosis. HIB was induced in juvenile swine by placing a constrictor on the left anterior descending (LAD) artery, causing myocardial ischemia without infarction.

Novel Therapeutic Approaches Enhance PGC1-alpha to Reduce Oxidant Stress-Inflammatory Signaling and Improve Functional Recovery in Hibernating Myocardium.

Ischemic heart disease affects millions of people around the world. Current treatment options, including coronary artery bypass grafting, do not result in full functional recovery, highlighting the need for novel adjunctive therapeutic approaches. Hibernation describes the myocardial response to prolonged ischemia and involves a set of complex cytoprotective metabolic and functional adaptations.

Persistent diastolic dysfunction in chronically ischemic hearts following coronary artery bypass graft.

Objective: A porcine model was used to study diastolic dysfunction in hibernating myocardium (HM) and recovery with coronary artery bypass surgery (CABG).

Methods: HM was induced in Yorkshire-Landrace juvenile swine (n = 30) by placing a c-constrictor on left anterior descending artery causing chronic myocardial ischemia without infarction. At 12 weeks, animals developed the HM phenotype and were either killed humanely (HIB group; n = 11) or revascularized with CABG and allowed 4 weeks of recovery (HIB+CABG group; n = 19).

The Troponin Complex: Discriminating the Signal from the Noise.

Patients presenting to the emergency department with consideration of an acute coronary syndrome (ACS) are risk-stratified with sensitive troponin assays. Among many patients who present with symptoms other than chest pain, they are admitted for observation if the troponin assay is above the upper reference limit of that specific assay. With the advent of high-sensitivity troponin assays, it is estimated that the prevalence of admissions for secondary myocardial infarctions, termed type 2 myocardial infarctions and myocardial injury, will increase by 100%.

In-Stent Restenosis in Saphenous Vein Grafts (from the DIVA Trial).

Saphenous vein grafts (SVGs) have high rates of in-stent restenosis (ISR). We compared the baseline clinical and angiographic characteristics of patients and lesions that did develop ISR with those who did not develop ISR during a median follow-up of 2.7 years in the DIVA study (NCT01121224).

Inside Out: Change Through Art.

Over the past three decades, there has been a 900% increase in the number of women experiencing incarceration in Minnesota. We wished to test whether handwriting, as creative visual art expression for women in jail, would be a positive experience for them as well as for individuals viewing the artwork during expositions. Over a 2-year period, the principal artist invited women residents from four separate county jails in Minnesota, to handwrite their thoughts on a sheet of paper.

Preventing Myocardial Injury Following Non-Cardiac Surgery: A Potential Role for Preoperative Antioxidant Therapy with Ubiquinone.

Over 240 million non-cardiac operations occur each year and are associated with a 15-20% incidence of adverse perioperative cardiovascular events. Unfortunately, preoperative therapies that have been useful for chronic ischemic heart diseases, such as coronary artery revascularization, antiplatelet agents, and beta-blockers have failed to improve outcomes. In a pre-clinical swine model of ischemic heart disease, we showed that daily administration of ubiquinone (coenzyme Q, CoQ) enhances the antioxidant status of mitochondria within chronically ischemic heart tissue, potentially via a PGC1α-dependent mechanism.

Stent-Only Versus Adjunctive Balloon Angioplasty Approach for Saphenous Vein Graft Percutaneous Coronary Intervention: Insights From DIVA Trial.

Background: Direct stenting without pre-dilation or post-dilation has been advocated for saphenous vein graft percutaneous coronary intervention to decrease the incidence of distal embolization, periprocedural myocardial infarction, and target lesion revascularization.

Methods: We performed a post hoc analysis of patients enrolled in the DIVA (Drug-Eluting Stents Versus Bare Metal Stents in Saphenous Vein Graft Angioplasty; NCT01121224) prospective, double-blind, randomized controlled trial. Patients were stratified into stent-only and balloon-stent groups.

CoQ enhances PGC1α and increases expression of mitochondrial antioxidant proteins in chronically ischemic swine myocardium.

Background: Expression of mitochondrial proteins is reduced within hibernating myocardium (HM). It is unclear whether dietary supplementation with CoQ can increase expression of mitochondrial electron transport chain (ETC) and antioxidant proteins within this tissue. In a swine model of HM, we tested whether dietary administration of CoQ for four weeks enhances the expression of ETC and antioxidant proteins within the mitochondria via increased PGC1α signaling.

NT-Pro BNP Predicts Myocardial Injury Post-vascular Surgery and is Reduced with CoQ: A Randomized Double-Blind Trial.

Background: NT-Pro BNP levels provide incremental value in perioperative risk assessment prior to major noncardiac surgery. Whether they can be pharmacologically modified in patients prior to an elective vascular operation is uncertain.

Methods: A double-blind, randomized controlled trial was implemented at a single institution.

Mitochondrial Respiratory Capacity is Restored in Hibernating Cardiomyocytes Following Co-Culture with Mesenchymal Stem Cells.

Hibernating myocardium is a subset of ischemic cardiac disease characterized by viable but dysfunctional tissue. Standard treatment for hibernating myocardium is coronary artery bypass graft, which reduces arrhythmias and improves survival but does not fully restore function, presenting a gap in currently available treatments. Large animal studies of hibernating myocardium have identified impaired mitochondrial dynamics as a root cause of persistent cardiac dysfunction despite surgical revascularization.

Utility of nuclear stress imaging in predicting long-term outcomes one-year post CABG Surgery.

Background: Early MPI after CABG is currently considered rarely appropriate in asymptomatic patients. This study aimed to identify prognostic value of nuclear stress-imaging post-CABG.

Methods: This was a single center prospective study looking at long-term outcomes post-CABG.

Intra-Atrial Right Coronary Artery and its Ablation Implications.

Objectives: The study examined the frequency in which a right coronary artery (RCA) anomaly resulting in intra-atrialization of the vessel might increase risk of RCA damage during routine radiofrequency ablation in the right atrium even with low power or temperature.

Background: Right coronary artery (RCA) injury with endocardial RF ablation of the right atrium is a rare complication.

Methods: This prospective observational study comprised an analysis of coronary artery anatomies in 331 patients who underwent autopsies at our institution from 2005 to 2014.

Post-Extrasystolic Potentiation as a Predictor of Recovery of Left Ventricular Dysfunction After Radiofrequency Catheter Ablation.

Objectives: This study hypothesizes that post-extrasystolic potentiation reflects left ventricle contractile reserve and therefore may predict an improvement of premature ventricular contraction (PVC)-induced cardiomyopathy after PVC ablation.

Background: Post-extrasystolic potentiation is a physiologic phenomenon of blood pressure accentuation after a PVC beat.

Methods: We performed a retrospective study of patients with a PVC burden of ≥10% PVC/24 h and left ventricular ejection fraction (LVEF) of <50% who underwent successful ablation between January 1, 2009, to June 30, 2015.

Surgical Swine Model of Chronic Cardiac Ischemia Treated by Off-Pump Coronary Artery Bypass Graft Surgery.

Chronic cardiac ischemia that impairs cardiac function, but does not result in infarct, is termed hibernating myocardium (HM). A large clinical subset of coronary artery disease (CAD) patients have HM, which in addition to causing impaired function, puts them at higher risk for arrhythmia and future cardiac events. The standard treatment for this condition is revascularization, but this has been shown to be an imperfect therapy.

Hospital Readmission Rates Following AMI: Potential Interventions to Improve Efficiency.

Objectives: Quality of care utilization measures for patients admitted to the hospital with an acute myocardial infarction (AMI) include length of stay (LOS) and 30-day readmission rates. Our aim was to test whether efforts resulting in reduced LOS in patients diagnosed as having AMI would result in a higher risk of readmission within 30 days of hospital discharge and whether specific interventions could be targeted to reduce readmissions.

Methods: Using data supplied by the Veterans Affairs Inpatient Evaluation Center, we analyzed both the readmissions within 30 days of an AMI and LOS and determined the timing of readmissions and associated diagnoses.