Left atrial dysfunction as a correlate of heart failure symptoms in hypertrophic cardiomyopathy

Background: Hypertrophic cardiomyopathy (HCM) represents a generalized myopathic process affecting both ventricular and atrial myocardium. We aimed to assess left atrial (LA) function by two-dimensional speckle tracking echocardiography and its relation with left ventricular (LV) function and clinical status in patients with HCM. Methods: We prospectively enrolled 37 consecutive patients with HCM and 37 normal subjects with similar age and gender distribution. Longitudinal LV strain (ε) and LA ε and strain rate (Sr) parameters (systolic, early diastolic, and late diastolic during atrial contraction) were assessed. Results: Peak LAε and LA Sr parameters were significantly lower in patients compared with controls (P ≤ .001 for all). In patients, all LA function parameters correlated with LVε (P < .003 for all). Indexed LA volume, LA function parameters, and mitral regurgitation degree were the main correlates of New York Heart Association class; late diastolic strain rate during atrial contraction was the only independent predictor of symptomatic status. Conclusion: In patients with HCM, LA function is significantly reduced and related to LV dysfunction. Moreover, LA booster pump function emerged as an independent correlate of heart failure symptoms in this setting.