The aim of this retrospective study is to evaluate the prognostic role of myocardial perfusion imaging (MPI) in patients with type 2 myocardial infarction (T2MI). T2MI is an increasingly common diagnosis in clinical practice. The management of this condition is controversial and the prognostic value of MPI has not been established in this setting. We retrospectively studied T2MI patients who underwent vasodilator gated MPI within 90 days of T2MI at a single tertiary care institution in 2013. Abnormal myocardial perfusion was defined as the perfusion defect involving ≥ 5% of left ventricular (LV) myocardium. Abnormal LV ejection fraction (EF) was defined as < 50% by gated images. The primary outcome was a composite of death, myocardial infarction (other than index event) or coronary revascularization (CR). There were 234 patients (62 ± 14 years, 57% men) with T2MI (peak troponin 0.2 ng/ml, interquartile 0.1-1.4), of whom 136 (58%) had an abnormal MPI. During a median follow-up of 20 months, 155 patients (66%) had the primary outcome (39% death, 42% MI, 5% CR). An abnormal MPI was associated with an increased risk of the primary outcome with a hazard ratio of 1.56, 95%CI (1.12-2.18, P = .008) that remained statistically significant after multivariate adjustment (1.45, 95%CI (1.02-2.06, P = .04))). Patients with T2MI are at high risk for death or cardiac events in the intermediate term. More than one-half of patients with T2MI have an abnormal MPI and this is associated with the increased risk of cardiac events during follow-up. Risk stratification with MPI after T2MI may identify patients who would benefit from aggressive risk reduction.

Patients with type 2 myocardial infarction (T2MI) are at high risk of mortality and cardiovascular events. We have previously demonstrated that a blunted heart rate response (HRR) to regadenoson is associated with increased risk of cardiovascular events in patients undergoing myocardial perfusion

Background: Gastrointestinal bleeding (GIB) remains a major morbid event during continuous flow left ventricular assist device (LVAD) support. This study investigated whether a common hemodynamic profile is associated with GIB in patients with LVADs. Methods and Results: A single institution analysis reviewed all patients who underwent right heart catheterization (RHC) following LVAD implant between January 1, 2006, and December 31, 2013, with followup through June 2015. Kaplan-Meier and multiphase hazard statistical methods were employed. Among 108 patients with 341 RHC, 55 hospitalizations for GIB occurred within 1 year of RHC. Freedom from GIB at 6 months was 92% in patients with pulse pressure >= 35 mmHg, compared with 76% with pulse pressure <35 mmHg. By multivariable analysis, the significant predictors of GIB were: older age at implant, number of prior GIB, lower pulse pressure, lower mean arterial pressure, and higher right atrial pressure (all P <.05). The magnitude of effect is influenced by pulse pressure. Conclusions: Greater pulsatility and less venous congestion, along with other factors, are associated with a lower risk for GIB. It is reasonable to adjust therapeutic strategies to target this hemodynamic profile in patients with a propensity for GIB.

Right heart failure (RHF) after left ventricular assist device (LVAD) is associated with poor outcomes. Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs) defines RHF as elevated right atrial pressure (RAP) plus venous congestion. The purpose of this study was to examine the diagnostic performance of the noninvasive Intermacs criteria using RAP as the gold standard. We analyzed 108 patients with LVAD who underwent 341 right heart catheterizations (RHC) between January 1, 2006, and December 31, 2013. Physical exam, echocardiography, and laboratory data at the time of RHC were collected. Conventional two-by-two tables were used and missing data were excluded. The noninvasive Intermacs definition of RHF is 32% sensitive (95% cardiac index (CI), 0.21–0.44) and 97% specific (95% CI, 0.95–0.99) for identifying elevated RAP. Clinical assessment failed to identify two-thirds of LVAD patients with RAP > 16 mm Hg. More than half of patients with elevated RAP did not have venous congestion, which may represent a physiologic opportunity to mitigate the progression of disease before end-organ damage occurs. One-quarter of patients who met the noninvasive definition of RHF did not actually have elevated RAP, potentially exposing patients to unnecessary therapies. In practice, if any component of the Intermacs definition is present or equivocal, our data suggest RHC is warranted to establish the diagnosis.

Right heart failure (RHF) after left ventricular assist device (LVAD) is associated with adverse events and poor outcomes. INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) defines RHF as elevated right atrial pressure (RAP) >16 mmHg measured directly by right heart catheterization (RHC) or indirectly by jugular venous distension or dilated inferior vena cava (Criterion 1), plus clinical or laboratory evidence of venous congestion (Criterion 2). The purpose of this study was to examine how noninvasive diagnosis of RHF by INTERMACS criteria correlated with direct measurement of RAP by RHC.

Introduction: Gastrointestinal (GI) bleeding remains a major morbid event during continuous flow left ventricular assist device (LVAD) support. Hypothesis: This study investigated whether a common ...

Human users of synthetic cannabinoids (SCBs) JWH-018 and JWH-073 typically smoke these drugs, but preclinical studies usually rely on injection for drug delivery. We used the cannabinoid tetrad and drug discrimination to compare in vivo effects of inhaled drugs with injected doses of these two SCBs, as well as with the phytocannabinoid Δ9-tetrahydrocannabinol (Δ9-THC). Mice inhaled various doses of Δ9-THC, JWH-018 or JWH-073, or were injected intraperitoneally (IP) with these same compounds. Rectal temperature, tail flick latency in response to radiant heat, horizontal bar catalepsy, and suppression of locomotor activity were assessed in each animal. In separate studies, mice were trained to discriminate Δ9-THC (IP) from saline, and tests were performed with inhaled or injected doses of the SCBs. Both SCBs elicited Δ9-THC-like effects across both routes of administration, and effects following inhalation were attenuated by pretreatment with the CB1 antagonist/inverse agonist rimonabant. No cataleptic effects were observed following inhalation, but all compounds induced catalepsy following injection. Injected JWH-018 and JWH-073 fully substituted for Δ9-THC, but substitution was partial (JWH-073) or required relatively higher doses (JWH-018) when drugs were inhaled. These studies demonstrate that the SCBs JWH-018 and JWH-073 elicit dose-dependent, CB1 receptor-mediated Δ9-THC-like effects in mice when delivered via inhalation or via injection. Across these routes of administration, differences in cataleptic effects and, perhaps, discriminative stimulus effects, may implicate the involvement of active metabolites of these compounds.