Exercise limitation associated with asymptomatic left ventricular impairment: analogy with stage B heart failure

Kosmala W; Jellis CL; Marwick TH,

Journal Of The American College Of Cardiology
[J Am Coll Cardiol], ISSN: 1558-3597, 2015 Jan 27; Vol. 65 (3), pp.

Stage B heart failure (SBHF) describes asymptomatic ventricular disease
that may presage the development of heart failure (HF) symptoms. This
entity has been largely defined by structural changes; the roles of
sensitive indicators of nonischemic left ventricular (LV) dysfunction,
such as LV strain, are undefined.Objectives: This study sought to
define the association of exercise capacity with left ventricular
hypertrophy (LVH) and systolic/diastolic dysfunction in asymptomatic
patients with HF risk factors.Methods: We used echocardiography to
study 510 asymptomatic patients (age 58 ± 12 years) with type 2
diabetes mellitus, hypertension, or obesity. The results of
cardiopulmonary exercise testing in patients with structural evidence
of SBHF were compared with those in patients with subclinical
dysfunction, defined by reduced LV strain (>-18%) or increased LV
filling pressure (E/e’ >13).Results: Compared with healthy subjects,
groups with LV abnormalities differed in terms of oxygen uptake (peak
VO2): 25.5 ± 8.2 versus 21.0 ± 8.2 for strain >-18% (p < 0.001); 26.4 ±
8.0 versus 19.0 ± 7.2 for E/e’ >13 (p < 0.0001); and 26.0 ± 7.7 versus
15.9 ± 6.9 ml/kg/min for LVH (p < 0.0001). SBHF, defined as ≥1 imaging
variable present, was associated with lower peak VO2 (beta = -0.20; p <
0.0001) and metabolic equivalents (beta = -0.21; p < 0.0001),
independent of higher body mass index and insulin resistance, older
age, male sex, and treatment with beta-blockers.

Conclusions: LVH,
elevated LV filling pressure, and abnormal myocardial deformation were
independently associated with impaired exercise capacity. Including
functional markers may improve identification of SBHF in nonischemic
heart disease.