Disturbed ventricular-arterial coupling and increased left atrial stiffness in a patient with heart failure with preserved ejection fraction and hyperaldosteronism: a case report

Left Atrial Stiffness Index Independently Predicts Exercise Intolerance and Quality of Life in Older, Obese Patients With Heart Failure With Preserved Ejection Fraction

BACKGROUND

Heart failure with preserved ejection fraction (HFpEF) is the fastest growing form of HF and is associated with high morbidity and mortality. The primary chronic symptom in HFpEF is exercise intolerance, associated with reduced quality of life. Emerging evidence implicates left atrial (LA) dysfunction as an important pathophysiologic mechanism. Here we extend prior observations by relating LA dysfunction to peak oxygen uptake (peak VO₂), physical function (distance walked in 6 minutes [6MWD]) and quality of life (Kansas City Cardiomyopathy Questionnaire).

METHODS AND RESULTS

We compared 75 older, obese, patients with HFpEF with 53 healthy age-matched controls. LA strain was assessed by magnetic resonance cine imaging using feature tracking. LA function was defined according to its 3 distinct phases, with the LA serving as a reservoir during systole, as a conduit during early diastole, and as a booster pump at the end of diastole. The LA stiffness index was calculated as the ratio of early mitral inflow velocity-to-early annular tissue velocity (E/e', by Doppler ultrasound examination) and LA reservoir strain. HFpEF had a decreased reservoir strain (16.4 ± 4.4% vs 18.2 ± 3.5%, P = .018), lower conduit strain (7.7 ± 3.3% vs 9.1 ± 3.4%, P = .028), and increased stiffness index (0.86 ± 0.39 vs 0.53 ± 0.18, P < .001), as well as decreased peak VO₂, 6MWD, and lower quality of life. Increased LA stiffness was independently associated with impaired peak VO₂ (β = 9.0 ± 1.6, P < .001), 6MWD (β = 117 ± 22, P = .003), and Kansas City Cardiomyopathy Questionnaire score (β = -23 ± 5, P = .001), even after adjusting for clinical covariates.

CONCLUSIONS

LA stiffness is independently associated with impaired exercise tolerance and quality of life and may be an important therapeutic target in obese HFpEF.

REGISTRATION

NCT00959660.

Left atrial stiffness in women with ischemia and no obstructive coronary artery disease: Novel insight from left atrial feature tracking

BACKGROUND

Women with signs and symptoms of ischemia and no obstructive coronary artery disease (INOCA) are at risk of heart failure with preserved ejection fraction (HFpEF); however, the mechanism for HFpEF progression remains unclear. Studies in INOCA have largely focused on left ventricular function. The left atrium serves an important role in maintaining transmitral flow, and is impaired in HFpEF; however, it remains unclear if left atrial function is impaired in INOCA.

HYPOTHESIS

Left atrial function is progressively worse in INOCA and HFpEF compared to controls.

METHODS

We compared 39 reference control subjects to 64 women with INOCA and 22 subjects with HFpEF. Left atrial strain was assessed by feature tracking using magnetic resonance cine images.

RESULTS

Peak left atrial strain was reduced in HFpEF compared to controls (22.9 ± 4.8% vs 25.9 ± 3.2%, P < .01), but similar in INOCA (24.8 ± 4.5%) compared to HFpEF and controls (P = .18). However, left ventricular end-diastolic pressure (LVEDP) was elevated in 33% of INOCA participants, suggesting that left atrial stiffness (LVEDP/LA strain) is elevated in a large portion of women with INOCA.

CONCLUSIONS

Taken together, we interpret these data to support our working hypothesis that INOCA is a pre-HFpEF state, with left atrial stiffness preceding overt left atrial dysfunction; representing a putative therapeutic target to prevent HFpEF progression in this at-risk population.