Istaroxime, a first in class new chemical entity exhibiting SERCA-2 activation and Na-K-ATPase inhibition: a new promising treatment for acute heart failure syndromes?

Acute heart failure syndromes (AHFS) are associated with the rapid onset of heart failure (HF) signs and symptoms. Hospitalizations for AHFS continue to rise and are associated with significant mortality and morbidity. Several pharmacological agents are currently approved for the treatment of AHFS, but their use is associated with an increase in short-term mortality. There is a need for new agents that can be given in the acute setting with increased efficacy and safety. Istaroxime is a unique agent with both inotropic and lusitropic properties which is currently being studied for the treatment of AHFS. Istaroxime inhibits the sodium-potassium adenosine triphosphatase (ATPase) and stimulates the sarcoplasmic reticulum calcium ATPase isoform 2 (SERCA-2) thereby improving contractility and diastolic relaxation. Early data from human studies reveal that istaroxime decreases pulmonary capillary wedge pressure (PCWP) and possibly improves diastolic function without causing a significant change in heart rate (HR), blood pressure, ischemic or arrhythmic events. Most commonly reported side effects were related to gastrointestinal intolerance and were dose related. In conclusion, istaroxime is a novel agent being investigated for the treatment of AHFS whose mechanism of action and cellular targets make it a promising therapy. Further studies with longer infusion times in patients with hypotension are required to confirm its efficacy and safety

Neurohormonal activation in acute heart failure: results from VERITAs

Objectives: Recent heart failure studies have suggested that inflammatory and immune system activation are associated with increased levels of cytokines, chemokines and inflammatory proteins during acutely decompensated heart failure. The objectives of this substudy were to evaluate the role of neurohormonal and inflammatory activation in the pathogenesis and outcome of acute heart failure (AHF) and the correlation between biomarker levels and clinical outcomes. Methods: Serum levels of B-type natriuretic peptide-32 (BNP-32), endothelin-1 (ET-1), norepinephrine, troponins I and T, C-reactive protein (CRP), von Willebrand factor, plasminogen activator inhibitor-1, interleukin-6 (IL-6) and tissue plasminogen activator (TPA) were measured at baseline, 24 and 48 h and 7 and 30 days in 112 patients with AHF recruited to the Value of Endothelin Receptor Inhibition with Tezosentan in Acute Heart Failure Study neurohormonal substudy. Results: On univariable analysis, CRP, BNP and ET-1 were predictive of worsening heart failure by day 30; when considered together, only CRP and BNP were significantly associated with this outcome. On adjustment for age, baseline blood pressure, serum sodium and serum creatinine, only age and BNP remained significant. CRP, IL-6 and TPA levels were significantly correlated with 180-day mortality on univariable analysis. Conclusion: Circulating markers of inflammation may be useful in gauging prognosis in patients with AHF

Prognostic value of coronary risk factors, exercise capacity and single photon emission computed tomography in liver transplantation candidates: A 5-year follow-up study.

BACKGROUND Although consensus-based guidelines support noninvasive stress testing prior to orthotopic liver transplantation (OLT), the optimal screening strategy for assessment of coronary artery disease in patients with end-stage liver disease (ESLD) is unclear. This study sought to determine the relative predictive value of coronary risk factors, functional capacity, and single photon emission computed tomography (SPECT) on major adverse cardiovascular events and all-cause mortality in liver transplantation candidates. METHODS Prior to listing for transplantation, 404 consecutive ESLD patients were referred to a University hospital for cardiovascular (CV) risk stratification. All subjects met at least one of the following criteria: inability to perform > 4 METs by history (62%), insulin-treated diabetes mellitus (53%), serum creatinine > 1.72 mg/dL (8%), history of MI, PCI or CABG (5%), stable angina (3%), cerebrovascular disease (1%), peripheral vascular disease (1%). Subjects underwent Technetium-99m SPECT with multislice coronary artery calcium scoring (CACS) using exercise treadmill or standard adenosine stress in those unable to achieve 85% maximal heart rate (Siemens Symbia T16). Abnormal perfusion was defined as a summed stress score (SSS) ≥ 4. RESULTS Of the 404 patients, 158 (age 59 ± 9 years; male 68%) subsequently underwent transplantation and were included in the primary analysis. Of those, 50 (32%) died after a mean duration follow-up of 5.4 years (maximal 10.9 years). Most deaths (78%) were attributed to noncardiovascular causes (malignancy, sepsis, renal failure). Of the 32 subjects with abnormal perfusion (20%), nine (6%) had a high-risk perfusion abnormality defined as a total perfusion defect size (PDS) ≥ 15% and/or an ischemic PDS ≥ 10%. Kaplan-Meier survival curves demonstrated abnormal perfusion was associated with increased CV mortality (generalized Wilcoxon, P = 0.014) but not all-cause death. Subjects with both abnormal perfusion and an inability to exercise > 4 METs had the lowest survival from all-cause death (P = 0.038). Abnormal perfusion was a strong independent predictor of CV death (adjusted HR 4.2; 95% CI 1.4 to 12.3; P = 0.019) and MACE (adjusted HR 7.7; 95% CI 1.4 to 42.4; P = 0.018) in a multivariate Cox regression model that included age, sex, diabetes, smoking and the ability to exercise > 4 METs. There was no association between CACS and the extent of perfusion abnormality, nor with outcomes. CONCLUSIONS Most deaths following OLT are noncardiovascular. Nonetheless, abnormal perfusion is prevalent in this high-risk population and a stronger predictor of cardiovascular morbidity and mortality than functional status. A combined assessment of functional status and myocardial perfusion identifies those at highest risk of all-cause death. (Exercise Capacity and Single Photon Emission Computed Tomography in Liver Transplantation Candidates [ExSPECT]; ClinicalTrials.gov Identifier: NCT03864497)