Efficacy and Safety Outcome of Angiotensin Receptor-Neprilysin Inhibitors (ARNIs) in Patients with Heart Failure and Preserved Ejection Fraction (HFpEF): Preliminary Results

Purpose: This study analyzes the safety and efficacy of LCZ696 (valsartan/sacubitril), a combination of angiotensin II receptor blocker and neprilysin inhibitor (ARNI), in patients with heart failure and preserved ejection fraction (HFpEF). Patients and Methods: An observational pilot study was conducted using a prospective design. A sample of 50 HFpEF patients (27 females and 23 males) was included on LCZ696 (50 mg orally, twice daily), which was then titrated up to a maximum tolerated dose, and followed up in the outpatient clinic. Thirty-seven patients received LCZ696 during hospitalization for decompensated heart failure or before their discharge while same titration was followed for the remaining patients. Results: Patients were classified as New York Heart Association (NYHA) class III (64%), NYHA class IV (22%), and NYHA class II (14%). Diabetes mellitus was found in 74% of patients, while hypertension in 94%. Rapid clinical improvement was found with significant reduction in NYHA class down to NYHA class II (p=0.018). Patients had cleared off the fine basal crackles (specific for the interstitial pulmonary disease) secondary to heart failure (p< 0.001) and improvement or disappearance of edema of the lower limbs (p< 0.001). Heart rate response and jugular venous pressure and NT-pro-BNP were reduced significantly (p-value < 0.001, 0.005, respectively). Echocardiographic criteria for diastolic LV dysfunction (primarily E/A ratio) improved (p=0.001). Serum sodium (NA) levels improved significantly (p=0.015), without worsening renal function or limiting hyperkalemia. Conclusion: LCZ696 (sacubitril/valsartan; ARNI) led to significant clinical improvements in patients with HFpEF. Further, a randomized study is needed to test whether it leads to positive outcomes for a larger sample. Ethical Approval: Project No. E-17-2414, King Saud University, Kingdom of Saudi Arabia.