[Different responses of right and left ventricular diastolic function to pulmonary resection: echocardiographic study with leg elevation for preload augmentation].

OBJECTIVES

The effects of pulmonary resection on cardiac function have not been well characterized. This study used Doppler echocardiography to evaluate preoperative and postoperative right and left ventricular function with preload augmentation by elevation of the legs.

METHODS

Twenty-one patients (12 males, 9 females, mean age 64 +/- 11 years) undergoing pulmonary resection for lung cancer underwent concurrent examination of cardiac and pulmonary function at 1 week preoperation and 4 weeks postoperation. Cardiac function of right and left ventricles was assessed by Doppler echocardiography to record waveforms of transtricuspid flow and transmitral flow. Assessment was made in the supine position and with leg elevation 60 degrees to apply preload augmentation. We measured the interval between cessation and onset of transatrioventricular flow, ventricular ejection time and Tei index as an index of global ventricular function. Peak velocity of early filling (E) and atrial contraction (A) were measured from the transtricuspid and transmitral flows to calculate E/A of the right and left ventricles (ER/AR, EL/AL). Pulmonary function tests yielded the forced vital capacity expressed as the ratio to the predicted value as an index for the pulmonary vascular bed area.

RESULTS

The postoperative cardiac function without preload augmentation was comparable to the preoperation function. With preload augmentation, the postoperative ER/AR was less than preoperation in the patients with postoperative forced vital capacity < or = 80% of the preoperation value. There was a significant correlation between the postoperation versus preoperation ratio of ER/AR and of forced vital capacity (r = 0.66, p = 0.0028) and ratio of right ventricular Tei index and of forced vital capacity (r = 0.61, p = 0.0034). There was a possibility that right ventricular Tei index indirectly indicated the state of pulmonary vascular bed area.

CONCLUSIONS

The right ventricular Tei index is useful to estimate preoperation and postoperation global right ventricular function. No close relationship between ER/AR and EL/AL at preoperation (r = 0.70, p = 0.0004) was found in the patients with postoperative right ventricular Tei index > 0.1 greater than at preoperation. Pulmonary resection might affect the diastolic function of the right ventricle more than the left ventricle, possibly because of reduced compliance of the right ventricle indicated by an increased atrial contraction at postoperation with preload augmentation.