Although estimation of left ventricular filling pressure (LVFP) using an integrated echocardiographic algorithm is recommended, the usefulness of this algorithm has not been fully validated.
The purpose of this study was to investigate the reliability of an algorithmic classification system using invasively measured left atrial pressure (LAP) in a large-scale cohort.
The authors enrolled 1,967 patients (age 68 ± 10 years) whose LAP was directly measured within the left atrium during catheter ablation for atrial fibrillation. Patients were classified into 3 groups based on the echocardiographic algorithm: normal (group N, n = 1,282), undetermined (group U, n = 160), and elevated (group E, n = 346) LAP groups. Invasively measured LAP and echocardiographic parameters estimating LVFP were compared among the groups.
The median LAP was 12.6 ± 5.7 mm Hg in the entire cohort. LAP was significantly higher in group E than that in the other groups (groups E vs U vs N, 14.2 ± 6.3 mm Hg vs 13.5 ± 5.9 mm Hg vs 12.0 ± 5.5 mm Hg; P < 0.001). Among group E patients, 43.1% had elevated LAP (≥15 mm Hg), whereas 56.9% had normal LAP (<15 mm Hg). Of the patients in group N, 69.0% had normal LAP, whereas 31% had elevated LAP. Although the correlation between invasively measured LAP and E/e\', peak tricuspid regurgitant velocity, and left atrial volume index was modest, the number of abnormal values correlated significantly with elevated LAP (P < 0.001).
The classification using combined echocardiographic parameters in the recommendations may be useful for detecting patients with normal LVFP but may be limited for detecting elevated LVFP.

Early, noninvasive identification of patients with heart failure with preserved ejection fraction (HFpEF) with congestion may allow timely tailoring of decongestive therapies. The 2016 American Society of Echocardiography and European Association of Cardiovascular Imaging guidelines provide an algorithm to assess for elevated left atrial pressure (LAP); the associations of echocardiographic LAP with clinical status and disease progression in patients with HFpEF are unclear.
Participants in the Phosphodiesterase-5 Inhibition to Improve Clinical Status and Exercise Capacity in HFpEF trial were categorized into one of four prespecified guideline-based echocardiographic LAP categories: (1) normal, (2) elevated, (3) atrial fibrillation (AF) at the time of echocardiography, or (4) indeterminate. Associations of echocardiographic LAP categories with baseline exercise capacity, change in exercise capacity, and change in N-terminal pro-B-type natriuretic peptide over 24 weeks were evaluated.
Of 216 participants, 199 underwent mitral inflow Doppler echocardiography for LAP categorization. Participants with elevated echocardiographic LAP (n = 81) or AF (n = 57) were older and had a higher prevalence of kidney dysfunction. Compared with the normal echocardiographic LAP group (n = 28), elevated echocardiographic LAP and AF were each independently associated with a greater reduction in peak oxygen consumption over 24 weeks after adjusting for baseline values and clinical covariates (β for elevated echocardiographic LAP = -1.55 [95% CI, -2.59 to -0.51], P = .004; β for AF = -1.33 [95% CI, -2.49 to -0.17], P = .03). Indeterminate echocardiographic LAP (n = 33) was also independently associated with a reduction in exercise capacity at 24 weeks compared with normal echocardiographic LAP (β = -1.35; 95% CI, -2.51 to -0.19; P = .02). Finally, elevated echocardiographic LAP and AF were significantly associated with increases in N-terminal pro-B-type natriuretic peptide over 24 weeks compared with normal echocardiographic LAP.
In patients with chronic HFpEF, elevated echocardiographic LAP and indeterminate echocardiographic LAP, as defined by contemporary guidelines, and AF were each independently associated with a reduction in exercise capacity compared with normal echocardiographic LAP. These findings suggest the potential utility of noninvasive LAP assessment in patients with HFpEF for tailoring treatments that decrease congestion.

Current European guidelines recommend periodic risk assessment for patients with pulmonary arterial hypertension (PAH). The aim of our study was to determine the association between the number of low-risk criteria achieved within 1 year of diagnosis and long-term prognosis.Incident patients with idiopathic, heritable and drug-induced PAH between 2006 and 2016 were analysed. The number of low-risk criteria present at diagnosis and at first re-evaluation were assessed: World Health Organization (WHO)/New York Heart Association (NYHA) functional class I or II, 6-min walking distance (6MWD) >440 m, right atrial pressure <8 mmHg and cardiac index ≥2.5 L·min-1·m-21017 patients were included (mean age 57 years, 59% female, 75% idiopathic PAH). After a median follow-up of 34 months, 238 (23%) patients had died. Each of the four low-risk criteria independently predicted transplant-free survival at first re-evaluation. The number of low-risk criteria present at diagnosis (p<0.001) and at first re-evaluation (p<0.001) discriminated the risk of death or lung transplantation. In addition, in a subgroup of 603 patients with brain natriuretic peptide (BNP) or N-terminal pro-brain natriuretic peptide (NT-proBNP) measurements, the number of three noninvasive criteria (WHO/NYHA functional class, 6MWD and BNP/NT-proBNP) present at first re-evaluation discriminated prognostic groups (p<0.001).A simplified risk assessment tool that quantifies the number of low-risk criteria present accurately predicted transplant-free survival in PAH.