Optimization of GDMT for patients with heart failure and reduced ejection fraction: can physiological and biological barriers explain the gaps in adherence to heart failure guidelines?

Heart failure is a growing epidemic with high mortality rates and recurrent hospital admissions that creates a burden on affected individuals, their caregivers and the whole healthcare system. Throughout the years, many randomized trials have established the effectiveness of several pharmacological therapies and electrophysiological devices to reduce hospitalizations and improve quality of life and survival, mostly for patients with heart failure with reduced ejection fraction (HFrEF). These studies led to the publication of national societies' recommendations to guide clinicians in the management of HFrEF. Yet, many reports have shown significant care gaps in adherence to these recommendations in clinical practice, highlighting suboptimal use and/or dosing of evidence-based therapies. Adherence to guidelines has been shown to be associated with the best prognosis in HFrEF, with patients presenting with intolerances or contraindications having the highest risk of events; however, it remains unclear whether this association is causal or merely a marker of more advanced disease. Furthermore, individual characteristics may limit the possibility of reaching the targeted dosage of specific agents. Herein, we provide a comprehensive overview of clinicians' adherence to heart failure guidelines in a specialized real-life setting, particularly regarding use and optimization of guideline-derived medical therapies, as well as the implementation of more recent agents such as sacubitril/valsartan and SGLT2 inhibitors. We seek potential explanations for suboptimal treatment and its impact on patient outcomes.

Optimization of pharmacotherapies for ambulatory patients with heart failure and reduced ejection fraction is associated with improved outcomes.

BACKGROUND: In heart failure, specific target doses for each drug are recommended, but some patients receive suboptimal dosing, others are undertreated or remain chronically in a titration phase, despite having no apparent contraindication or intolerance. We assessed the association of different levels of adherence to guidelines with outcomes in patients with heart failure and reduced ejection fraction (HFrEF). METHODS: Medical records of patients with HFrEF followed at our heart failure (HF) clinic for at least 6 months (n = 511) were reviewed and patients categorized as: 1) optimized (25.4%); 2) in-titration (29.0%); 3) undertreated (32.7%); and 4) intolerant/contraindicated (12.9%). Risk of mortality or HF events (hospitalization, emergency visit or ambulatory administration of intravenous diuretics) within one year was assessed using Cox regression models and Kaplan-Meier curves. RESULTS: Compared to optimized patients, those intolerant (HR: 4.60 [95%CI: 2.23-9.48]; p < 0.0001) had the highest risk of outcomes, followed by those undertreated (3.45 [1.78-6.67]; p = 0.0002) and in-titration (1.99 [0.97-4.06]; p = 0.0588). Overall predictors of outcomes included loop diuretics' use (4.54 [2.39-8.60]), undertreatment (2.38 [1.22-4.67]), intolerance/ contraindication to triple therapy (3.08 [1.47-6.42]), peripheral vascular disease (2.13 [1.29-3.50]) and NYHA class III-IV (1.89 [1.25-2.85]); all p < 0.05. CONCLUSION: Level of adherence to guidelines is associated with outcomes, with intolerant/contraindicated patients having the worst prognosis and those undertreated and in-titration at intermediate risk compared to those optimized. Up-titration of therapy should be attempted whenever possible, considering patients' limitations, to potentially improve outcomes.

Care Gaps in Adherence to Heart Failure Guidelines: Clinical Inertia or Physiological Limitations?

OBJECTIVES: This study evaluated the impact of clinical and physiological factors limiting treatment optimization toward recommended medical therapy in heart failure (HF). BACKGROUND: Although guidelines aim to assist physicians in prescribing evidence-based therapies and to improve outcomes of patients with HF and reduced ejection fraction (HFrEF), gaps in clinical care persist. METHODS: Medical records of all patients with HFrEF followed for at least 6 months at the authors' HF clinic (n = 511) allowed for drug optimization and were reviewed regarding the prescription rates of recommended pharmacological agents and devices (implantable cardioverter-defibrillator [ICD] or cardiac resynchronization therapy [CRT]). Then, an algorithm integrating clinical (New York Heart Association [NYHA] functional class, heart rate, blood pressure and biologic parameters (creatinine, serum potassium) based on the inclusion/exclusion criteria of landmark trials guiding these recommendations) was applied for each agent and device to identify potential explanations for treatment gaps. RESULTS: Gross prescription rates were high for beta-blockers (98.6%), mineralocorticoid receptor antagonist (MRA) (93.4%), vasodilators (90.3%), ICDs (75.1%), and CRT (82.1%) among those eligible, except for ivabradine (46.3%, n = 41). However, achievement of target physiological doses was lower (beta-blockers, 67.5%; MRA, 58.9%; and vasodilators, 63.4%), and one-fifth of patient dosages were still being up-titrated. Suboptimal doses were associated with older age (odds ratio [OR]: 1.221; p < 0.0001) and history of stroke or transient ischemic attack (TIA) (no vs. yes, OR: 0.264; p = 0.0336). CONCLUSIONS: Gaps in adherence to guidelines exist in specialized HF setting and are mostly explained by limiting physiological factors rather than inertia. Older age and history of stroke/TIA, potential markers of frailty, are associated with suboptimal doses of guideline-directed medical therapy, suggesting that an individualized rather than a "one-size-fits-all" approach may be required.