Background: Increased right ventricular afterload leads to left ventricular diastolic dysfunction due to ventricular interdependence. Increased right ventricular afterload is frequently present in patients with COPD. The purpose of this study was to determine whether left ventricular diastolic dysfunction could be detected in COPD patients with normal or elevated pulmonary artery pressure (PAP).
Methods: Twenty-two patients with COPD and 22 matched control subjects underwent pulsed Doppler echocardiography. Left ventricular systolic dysfunction and other causes of left ventricular diastolic dysfunction (eg, coronary artery disease) were excluded in all patients and control subjects. PAP was measured invasively in 13 patients with COPD.
Results: The maximal atrial filling velocity was increased and the early filling velocity was decreased in patients with COPD compared to control subjects. The early flow velocity peak/late flow velocity peak (E/A) ratio was markedly decreased in patients with COPD compared to control subjects (0.79 +/- 0.035 vs 1.38 +/- 0.069, respectively; p < 0.0001), indicating the presence of left ventricular diastolic dysfunction. The atrial contribution to total left diastolic filling was increased in patients with COPD. This was also observed in COPD patients with normal PAP, as ascertained using a right heart catheter. The atrial contribution to total left diastolic filling was further increased in COPD patients with PAP. PAP correlated with the E/A ratio (r = -0.85; p < 0.0001).
Conclusions: Left ventricular diastolic dysfunction is present in COPD patients with normal PAP and increases with right ventricular afterload.