New paradigm shift in the pharmacotherapy for heart failure-where are we now and where are we heading?

Timing of prescription of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers in patients hospitalized for acute heart failure with reduced/mildly reduced ejection fraction: a retrospective analysis

Although angiotensin-converting enzyme inhibitors (ACEis) and angiotensin II receptor blockers (ARBs) play critical roles in the treatment of heart failure with reduced or mildly reduced ejection fraction (HFrEF/HFmrEF; left-ventricular ejection fraction ≤ 50%), the ideal timing for initiation in patients with acute heart failure (AHF) is unclear. We sought to clarify the timing and safety of ACEi/ARB prescription relative to hemodynamic stabilization (pre or post) in patients hospitalized with acute HFrEF/HFmrEF. This was a retrospective, observational analysis of electronic data of patients hospitalized for AHF at 17 Japanese hospitals. Among 9107 patients hospitalized with AHF, 2648 had HFrEF/HFmrEF, and 83.0% met the hemodynamic stabilization criteria within 10 days of admission. During hospitalization, 63.5% of patients with HFrEF/HFmrEF were prescribed an ACEi/ARB, 79.4% of which were prescribed pre-stabilization. In a multivariable analysis, patients treated with an ACEi/ARB pre-stabilization were more likely to have comorbid hypertension, diabetes mellitus, or ischemic heart disease. ACEi/ARB prescription timing was not associated with adverse events, including hypotension and renal impairment, and early prescription was associated with a lower incidence of subsequent worsening of HF. In clinical practice, more hospitalized patients with AHF received an ACEi/ARB before compared with after hemodynamic stabilization, and no safety concerns were observed. Moreover, early prescription may be associated with a lower incidence of worsening HF.

Characterization of Stimulatory Action on Voltage-Gated Na+ Currents Caused by Omecamtiv Mecarbil, Known to Be a Myosin Activator

Omecamtiv mecarbil (OM, CK-1827452) is recognized as an activator of myosin and has been demonstrated to be beneficial for the treatment of systolic heart failure. However, the mechanisms by which this compound interacts with ionic currents in electrically excitable cells remain largely unknown. The objective of this study was to investigate the effects of OM on ionic currents in GH3 pituitary cells and Neuro-2a neuroblastoma cells. In GH₃ cells, whole-cell current recordings showed that the addition of OM had different potencies in stimulating the transient (I_Na(T)) and late components (I_Na(L)) of the voltage-gated Na⁺ current (I_Na) with different potencies in GH₃ cells. The EC₅₀ value required to observe the stimulatory effect of this compound on I_Na(T) or I_Na(L) in GH₃ cells was found to be 15.8 and 2.3 µM, respectively. Exposure to OM did not affect the current versus voltage relationship of I_Na(T). However, the steady-state inactivation curve of the current was observed to shift towards a depolarized potential of approximately 11 mV, with no changes in the slope factor of the curve. The addition of OM resulted in an increase in the decaying time constant during the cumulative inhibition of I_Na(T) in response to pulse-train depolarizing stimuli. Furthermore, the presence of OM led to a shortening of the recovery time constant in the slow inactivation of I_Na(T). Adding OM also resulted in an augmentation of the strength of the window Na⁺ current, which was evoked by a short ascending ramp voltage. However, the OM exposure had little to no effect on the magnitude of L-type Ca²⁺ currents in GH₃ cells. On the other hand, the delayed-rectifier K⁺ currents in GH₃ cells were observed to be mildly suppressed in its presence. Neuro-2a cells also showed a susceptibility to the differential stimulation of I_Na(T) or I_Na(L) upon the addition of OM. Molecular analysis revealed potential interactions between the OM molecule and hNa_V1.7 channels. Overall, the direct stimulation of I_Na(T) and I_Na(L) by OM is assumed to not be mediated by an interaction with myosin, and this has potential implications for its pharmacological or therapeutic actions occurring in vivo.

Promising directions in the treatment of chronic heart failure: improving old or developing new ones?

Unprecedented advances of recent decades in clinical pharmacology, cardiac surgery, arrhythmology, and cardiac pacing have significantly improved the prognosis in patients with chronic heart failure (CHF). However, unfortunately, heart failure continues to be associated with high mortality. The solution to this problem consists in simultaneous comprehensive use in clinical practice of all relevant capabilities of continuously improving methods of heart failure treatment proven to be effective in randomized controlled trials (especially when confirmed by the results of studies in real clinical practice), on the one hand, and in development and implementation of innovative approaches to CHF treatment, on the other hand. This is especially relevant for CHF patients with mildly reduced and preserved left ventricular ejection fraction, as poor evidence base for the possibility of improving the prognosis in such patients cannot justify inaction and leaving them without hope of a clinical improvement in their condition. The lecture consistently covers the general principles of CHF treatment and a set of measures aimed at inotropic stimulation and unloading (neurohormonal, volumetric, hemodynamic, and immune) of the heart and outlines some promising areas of disease-modifying therapy.