Positive end-expiratory pressure aggravates left ventricular diastolic relaxation further in patients with pre-existing relaxation abnormality

Positive end-expiratory pressure (PEEP) has been known to adversely influence cardiac output. Even though left ventricular (LV) diastolic function significantly contributes to LV performance, the effects of PEEP on LV diastolic function remains controversial. We, therefore, aimed to examine the effects of PEEP on LV diastolic function by use of pulsed wave Doppler tissue imaging in patients with pre-existing LV relaxation abnormality. Seventeen patients with peak early diastolic velocity of lateral mitral annulus (E) 8.5 cm s(1) among patients who underwent coronary artery bypass graft surgery were evaluated. Echocardiographic and haemodynamic variables were measured with 0, 5, and 10 cmH(2)O of PEEP. E and deceleration time (DT) of peak early transmitral filling velocity (E) were used as echocardiographic indicators of LV diastolic function. Mean arterial blood pressure decreased during 10 cmH(2)O PEEP, compared with that during 0 cmH(2)O PEEP. E showed a gradual and significant decrease with an incremental increase in PEEP (6.90.9, 5.80.9, and 5.21.2 cm s(1) during 0, 5, and 10 cmH(2)O PEEP, respectively), and DT of E was prolonged during 10 cmH(2)O PEEP, compared with that during 0 cmH(2)O PEEP. Increasing PEEP led to a progressive decline in LV relaxation in patients with pre-existing LV relaxation abnormality.