Selective Enhancement of Swine Myocardium with a Novel Ultrasound Enhancing Agent During Transthoracic Echocardiography.

Ultrasound enhancing agents are approved to delineate the endocardial border and opacify the left ventricle cavity (LVC). We present a nested phase change agent (NPCA) designed to enable selective myocardial enhancement without enhancing the LVC by employing a dual-activation mechanism dependent on sufficient ultrasound intensity and the microenvironment of the myocardium. Swine received bolus injections of NPCA while echocardiograms were collected and processed to determine background-subtracted acoustic intensities (AI) in the LVC and septal myocardium. At mechanical index (MI) ≥ 0.8, the NPCA enhanced the myocardium selectively (p < 0.001) while the LVC remained at baseline AI. A 5-mL bolus of NPCA enhanced swine myocardium and enhancement persisted for > 5 min at 1.4 MI, while hemodynamics and EKG remained normal. Our findings demonstrate that the NPCA enhances swine myocardium selectively without enhancing the LVC. The NPCA could have utility for functional and structural echocardiographic studies with clinical ultrasound using standard settings.

Peripheral Administration of Nitroglycerin in Pulseless Ventricular Tachycardia due to Cocaine-Induced Coronary Vasospasm.

Cocaine use accounts for 40% of the annual drug use related emergency department visits in the United States. Cocaine use is hence recognized as a major health problem. Cocaine blocks the presynaptic reuptake of norepinephrine and dopamine. The resulting increased adrenergic activity leads to vasoconstriction. Additionally, via various mechanisms, cocaine leads to a prothrombotic state and increases myocardial demand. Cocaine can cause coronary vasospasm and is therefore, associated with acute myocardial injury even in the absence of pre-existing atherosclerotic coronary artery disease. Nitroglycerin has a class 1C indication by the ACCF/AHA guidelines for patients with ST-segment elevation or depression that accompanies ischemic chest discomfort in the setting of cocaine use. It has been shown to reverse cocaine-induced coronary vasospasm and chest pain. In this case report, for the first time, we discuss how intravenous administration of high dose nitroglycerin to a patient in pulseless ventricular tachycardia with angiographically confirmed vasospasm induced by cocaine resulted in return of spontaneous circulation.

Randomized controlled trial of different aspirin regimens for reduction of niacin-induced flushing.

PURPOSE: Results of a study to test the hypothesis that taking niacin simultaneously with different forms of aspirin would reduce the occurrence of niacin-induced flushing are reported. METHODS: Traditionally, taking enteral absorbed aspirin 30 minutes before a niacin dose has been shown to reduce flushing by 30-50% relative to nonuse of aspirin. The objective of the study was to evaluate the efficacy of enteral absorbed and orally dissolved aspirin, taken at the same time as niacin, in reducing the frequency of moderate-to-severe flushing. In a prospective, double-blind, placebo-controlled crossover trial, healthy adult male and female volunteers were asked to take aspirin or a placebo (both agents were taken in both orally dissolved and swallowed formulations) immediately before niacin administration. Subjects then self-evaluated flushing symptoms on a validated scale. RESULTS: Simultaneous administration of swallowed aspirin and niacin reduced moderate-to-severe flushing events by a mean of 36.1%, from 2.35 to 1.5 events per subject (p = 0.003), relative to event rates with use of niacin alone. In a subset of subjects who had experienced moderate-to-severe flushing symptoms despite taking swallowed aspirin, flushing in response to subsequent niacin use was decreased by 20.5% (p = 0.05) with coadministration of orally dissolved aspirin and by 18.0% with a regimen containing both orally dissolved and swallowed aspirin (p = 0.03). CONCLUSION: Novel regimens of niacin and aspirin, including orally dissolved aspirin, were effective in reducing niacin-induced flushing in a small sample of healthy adult volunteers.

Synthetic Cannabinoid Abuse Resulting in ST-Segment Elevation Myocardial Infarction Requiring Percutaneous Coronary Intervention.

BACKGROUND: Synthetic cannabinoids (SC) are recreational designer drugs intended to mimic delta-9-tetrahydrocannabinol while surreptitiously circumventing classification by the Drug Enforcement Administration. CASE REPORT: A 50-year-old black male arrived in the Emergency Department transported by Emergency Medical Services (EMS) for altered mental status after complaining of chest pain associated with smoking SCs. EMS found the patient with an empty foil pack labeled "Scooby Snax Limited Edition Blueberry Potpourri." The patient was somnolent, but became agitated when stimulated and complained of chest pain. Vital signs were blood pressure 87/52 mm Hg and pulse 52 beats/min. The electrocardiogram demonstrated an inferior wall myocardial infarction. Coronary angiography identified an occluded obtuse marginal second branch that was successfully opened with a drug-eluting stent. The patient recovered uneventfully. Urine drug screen was negative for cocaine, and gas chromatography/mass spectrometry testing of the smoked material identified PB-22 and AMB-FUBINACA as the active ingredients. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians and cardiologists need to be aware that the mechanism of action of synthetic cannabinoids on the endocannabinoid system may result in acute ST-segment elevation myocardial infarction requiring percutaneous coronary intervention.