Background The pathophysiology of heart failure with normal ejection fraction (HFNEF) is complex and not fully understood. We hypothesised that left ventricular hypertrophy (LVH) which is found in most patients with HFNEF might lead to intramural dyssynchrony and uncoupling of the complex 3-dimensional motion of the left ventricle (LV) particularly on exercise.
Method 33 patients with the clinical diagnosis of HFNEF (age 69±11 years, 19 female, EF 60±7%) and LVH (according to American Society of Cardiology, female >95 g/m2, male 115 g/m2) underwent detailed 2D-echocardiography at rest and on supine exercise. They were compared to 41 clinically diagnosed HFNEF patients without LVH (age 73±8 years, 26 females, EF 61±7%) and 35 age-matched control subjects (age 71±7 years, 27 females, EF 63±7). All subjects underwent cardiopulmonary exercise test to assess peak oxygen consumption (peak VO2). Echocardiographic images were analysed off-line. Apical and basal rotation and radial displacement were measured by speckle tracking. Longitudinal displacement was assessed by colour tissue Doppler imaging. Raw data and timing of events were analysed using a custom-written interpolation algorithm. SDSM (SD of four LV peak systolic motions: basal and apical rotation, longitudinal and radial displacement) was calculated.
Results SDSM was comparable at rest for all three groups but controls showed the highest reduction in SDSM compared to both groups of patients on exercise. Patients with LVH had the smallest reduction in SDSM implying greater dyssynchrony in LV motions on exercise. SDSM on exercise correlated with left ventricular mass index (r=0.362, p=0.002) and VO2max (r=−0.319, p=0.011).
Conclusion LVH in patients with HFNEF is associated with intramural dyssynchrony and uncoupling of the complex 3-dimensional LV motions on exercise. This might contribute to their exertional symptoms.
- heart failure