Echocardiographic detection of occult cor pulmonale during exercise in patients with chronic obstructive pulmonary disease

We tested the ability of cycle ergometer exercise echocardiography to detec t cases of occult cor pulmonale among 25 patients with chronic obstructive pulmonary disease (COPD). The M-mode echocardiographic ventricular septal m otion, Left ventricular shape determined by short-axis two-dimensional (2-D ) echocardiography, and right and Left ventricular pressure curves were rec orded at rest and during exercise and were compared between patients. The v entricular septal motion was normal at rest in all of the patients. In nine patients (dip group), there was marked downward ventricular septal motion in early diastole during exercise, indicating distortion of the left ventri cular shape. There were no distinct changes in the remaining 16 patients (n on-dip group). At rest, the cardiac index teas significantly Lower, and rig ht ventricular systolic and mean pulmonary artery pressures were significan tly higher in the dip group than in the non-dip group. However, no signific ant difference was noted in the right ventricular end-diastolic pressure be tween the two groups at rest. The right ventricular systolic and end-diasto lic pressures were greater during exercise in the dip group than in the non -dip group. In all of the patients in the dip group, the right ventricular pressure exceeded the left ventricular pressure only in early diastole, coi nciding with the early diastolic dip of the ventricular septum, during exer cise. In conclusion, occult cor pulmonale can. be diagnosed accurately by t he appearance of an early diastolic dip of the ventricular septum and disto rted left ventricular shape during exercise in, patients with COPD.