Approximately 50% of heart failure patients have a preserved ejection fraction (HFpEF), a condition which is particularly complex to both diagnose and treat. Compared to HF patients with reduced ejection fraction (HFrEF), HFpEF patients are often older, female, and present with increased metabolic comorbidities such as obesity, hypertension, and type 2 diabetes mellitus. These metabolic comorbidities are associated with an increased risk of developing HFpEF: leading to a concerning increase in metabolic syndrome. Indeed, the prevalence of HFpEF has not only spiked in the last few decades, but also coincided with the rise of metabolic syndrome. Moreover, current pharmacological therapies that have demonstrated success in reducing morbidity and mortality in HFrEF patients are ineffective in patients with HFpEF.
Diagnosing HFpEF is further challenging because symptoms are often indistinguishable with HFrEF. This is especially true during the early stages of HFpEF, when a normal ejection fraction and lack of additional symptoms can contribute to an undetected condition. One of the few present symptoms in early stages is exercise dyspnea, due to fluid accumulation in the lungs: common in patients with HF. Yet properly evaluating reduced exercise capacity is challenging in older and obese patients, most of whom constitute the HFpEF patient population. Diagnosis of HFpEF becomes more complex when considering the lack of consensus regarding the definition of EF cut-off criteria, coupled with the fact that such diagnosis must be based upon the exclusion of other common symptoms associated with heart failure.
A particular challenge concerns the diagnosis of HFpEF in patients that present with unexplained exertional dyspnea; in this setting, right-sided heart catherization followed by invasive exercise testing may be required to distinguish between cardiac and non-cardiac causes, and to confirm a diagnosis of HFpEF. However, many clinicians agree that the invasive nature of these procedures does not make them well-suited for routine clinical practice. Dr. Yogesh Reddy and colleagues recently developed and validated a non-invasive score to help clinicians determine the likelihood of HFpEF in patients presenting with unexplained exertional dyspnea. The score, termed H2FPEF, is based on the presence or absence of several measurable risk factors: BMI >30 kg/m2, hypertension defined as currently on two or more antihypertensive medications, paroxysmal or persistent atrial fibrillation, pulmonary hypertension defined as pulmonary artery systolic pressure > 35 mmHg, age >60 years, higher filling pressures defined as E/e’ >9 and ranges from 0-9 points (a higher score likely indicates a greater probability that a patient has HFpEF). Indeed, when validated in a separate test cohort, an increased H2FPEF score was predictive of HFpEF probability: for example, a H2FPEF score of >5 helped to predict HFpEF with 90% probability. This score could prove useful in establishing the probability of HFpEF, and rule out this disease in patients with low scores (e.g. 0 or 1). Furthermore, the score could help guide clinicians in confirming a diagnosis in patients with higher (6-9) scores.
Reference:
Reddy, Yogesh NV, et al. “A Simple, Evidence-Based Approach to Help Guide Diagnosis of Heart Failure with Preserved Ejection Fraction.” Circulation (2018): CIRCULATIONAHA-118.
