Passive Leg Raise: An Indispensable Maneuver in the Study of Heart Failure with Preserved Ejection Fraction

Heart failure (HF) with preserved ejection fraction (HFpEF) accounts for at least 50% of the HF population, with an increasing prevalence. Its diagnosis is based on the presence of typical symptoms and increased filling pressures, with an ejection fraction greater than 50%.

In some cases—especially in the earlier stages of the disease—, laboratory and echocardiographic markers may be suboptimal to diagnose HFeEF, because filling pressures only increase in the presence of physiological stress (occult-HFpEF). Therefore, invasive tests such as pulmonary artery catheterization (PAC) with exercise should be considered an excellent option in these scenarios.

The possibility of performing exercise during PAC presents technical difficulties, so maneuvers that rapidly increase venous return, including passive leg raise (PLR), have been proposed as an alternative.

The aim of this study was to determine whether the PLR maneuver during PAC can be used to increase the diagnostic yield or rule out the diagnosis of occult-HFpEF.

The study included 109 patients from a tertiary pulmonary hypertension and HFpEF center, mainly women, with a mean age of 64 years, diagnosed with HFpEF using the H2FPEF score. These patients underwent CAP with pulmonary capillary wedge pressure (PCWP) measurement. They were categorized into three groups: Manifest-HFpEF (PCWPREST ≥15 mm Hg and PCWPEXERCISE ≥25 mm Hg), occult-HFpEF (PCWPREST <15 mm Hg and PCWPEXERCISE ≥25 mm Hg), or non-HFpEF (PCWPREST <15 mm Hg and PCWPEXERCISE <25 mm Hg). The PLR maneuver consisted in the raising of a leg at 50° by an assistant for 3 minutes.

PCWPPLR had a significantly higher predictive value for the diagnosis of occult-HFpEF, compared with PCWPREST (AUC = 0.82 vs. 0.69, p = 0.03).

PCWPPLR ≥19 can be used as an unequivocal cut-off point, with a specificity and positive predictive value of 100%, while a cut-off point of PCWPPLR <11 can be used to rule out occult-HFpEF (>11 has a 100% sensitivity). These cut-off points were subsequently confirmed in an external validation cohort.

Conclusions

In this study, incorporating the PLR maneuver during PAC significantly increased the diagnostic yield compared with resting measurements. This test is risk-free and less time consuming (when compared with a water overload challenge). Therefore, it should be considered an invaluable tool in the hemodynamic study of patients with suspected HFpEF.