Clinical, echocardiographic and prognostic outcomes of patients with concordant and discordant high-gradient aortic stenosis in an Asian cohort

High-Gradient Aortic Stenosis With Valve Area >1.0 cm2: The "Forgotten" Discordant Hemodynamic Phenotype

BACKGROUND

Clinical features and outcomes in severe aortic stenosis (AS) have been described according to the hemodynamic phenotypes.

OBJECTIVES

The aim of this study was to investigate the clinical features and prognosis of patients with high-gradient (HG) AS with aortic valve area (AVA) >1.0 cm2.

METHODS

A total of 3,209 patients were identified according to AVA (cm2), peak velocity (m/s), systolic mean pressure gradient (MG) (mm Hg): HG-AVA >1 = >1.0, ≥4, and ≥40, HG-AVA ≤1 = ≤1.0, ≥4, and ≥40; LG-AVA ≤1 (low-gradient) = ≤1.0, <4, and <40; moderate AS = 1.0 

RESULTS

HG-AVA >1 accounted for 230 individuals (7.2%). Compared with others, patients with HG-AVA >1 were younger (70.2 ± 12.0 years), more frequently male (85.7%), had fewer comorbidities, larger body surface area and stroke volume (115 ± 19.3 mL), and had higher prevalence of bicuspid valve (39.6%). After a follow-up of 944 days (Q1-Q3: 27-2,212 days), 1,523 deaths occurred. Compared with the HG-AVA >1 group, all-cause mortality was higher in HG-AVA ≤1 (HR: 1.4; 95% CI: 1.1-1.7), LG-AVA ≤1 (HR: 2.8; 95% CI: 2.2-3.6), and moderate AS (HR: 1.4; 95% CI: 1.1-1.7). These differences were no longer significant after adjustment for age, comorbidities, bicuspid valve, and cardiac function. In the HG-AVA >1 group, patients with aortic valve replacement had better survival outcomes than those without aortic valve replacement (P < 0.001) after balancing the 2 groups.

CONCLUSIONS

The underlying relative high-flow status is responsible for HG in patients with HG-AVA >1. This profile has better prognosis than others, being related to underlying younger age and better general and cardiac conditions, but aortic valve replacement may still benefit these patients.

Collapse

Key Words

• aortic stenosis
• echocardiography
• prognosis
• valve disease
• valve gradient

Collapse

MESH Headings

• Humans
• Male
• Aortic Valve Stenosis/physiopathology
• Aortic Valve Stenosis/diagnostic imaging
• Aortic Valve Stenosis/mortality
• Aortic Valve Stenosis/surgery
• Female
• Aged
• Hemodynamics
• Aortic Valve/physiopathology
• Aortic Valve/diagnostic imaging
• Aortic Valve/surgery
• Phenotype
• Severity of Illness Index
• Risk Factors
• Aged, 80 and over
• Middle Aged
• Retrospective Studies
• Prognosis
• Time Factors
• Predictive Value of Tests
• Risk Assessment

Collapse

Grants Collapse

Affiliation(s)

Saki Ito Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA
Jae K Oh Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA
Hector I Michelena Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA
Alexander C Egbe Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA
Heidi M Connolly Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA
Patricia A Pellikka Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA
Vuyisile T Nkomo Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA
Bradley R Lewis Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, Minnesota, USA
William R Miranda Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota, USA.

Collapse

Prevalence and Outcomes of Patients With Discordant High-Gradient Aortic Stenosis

BACKGROUND

Conflicting prognostic results have been reported in patients with discordant high-gradient aortic stenosis ([DHG-AS] the combination of a mean pressure gradient ≥40 mm Hg and an aortic valve area [AVA] >1 cm2). Moreover, existing studies only included selected patients without concomitant aortic regurgitation.

OBJECTIVES

The authors assessed the prevalence and survival of patients presenting with DHG-AS in an unselected group of consecutive patients presenting to the echocardiography laboratory of a tertiary referral center.

METHODS

A total of 3,547 adult patients with AVA ≤1.5 cm2 and peak aortic jet velocity ≥2.5 m/s or mean gradient ≥25 mm Hg who presented between 2005 and 2015 were included. Baseline clinical and echocardiographic data, and, when available, aortic valve calcium (AVC) score were collected in an institutional database, with subsequent retrospective analysis. The primary endpoint was all-cause mortality during follow-up.

RESULTS

DHG-AS was observed in 163 patients (11.6% of patients with a high gradient). After adjustment for potential confounders, overall mortality rate of patients with DHG-AS was similar to that of patients with concordant severe aortic stenosis (HR: 0.98 [95% CI: 0.66-1.44]; P = 0.91), and patients with discordant low-gradient aortic stenosis (HR: 0.85 [95% CI: 0.58-1.26]; P = 0.42), and higher than concordant moderate aortic stenosis (HR: 0.54 [95% CI: 0.36-0.81]; P = 0.003). After adjustment for aortic velocities, aortic regurgitation had no significant impact on survival. AVC was higher than in patients with concordant moderate aortic stenosis and discordant low-gradient aortic stenosis, and not significantly different from that of concordant severe aortic stenosis.

CONCLUSIONS

DHG-AS is not uncommon. Whereas AVA >1.0 cm2 is often seen as moderate aortic stenosis, a high-pressure gradient conveys a poor prognosis, whatever the AVA and the severity of concomitant aortic regurgitation.