The effect of respiration on left ventricular diastolic filling as assessed by radionuclide ventriculography

Left ventricular function is modified by respiration and pericardial constr aint. The aim of this study was to compare left ventricular systolic and di astolic function during inspiration and expiration in four patient groups: patients (1) without cardiac disease, (2) with severe pulmonary disease, (3 ) with cardiac amyloid and (4) with pericardial constriction (before and af ter pericardiectomy). Using blood-pool left ventriculography with modified gating, we obtained time-activity curves at the onset of inspiration and ex piration. On inspiration and expiration, patients with pericardial constric tion and patients with cardiac amyloid were significantly different from th ose without cardiac disease End those with severe pulmonary disease, in tha t left ventricular ejection fraction (LVEF) was less, peak filling rate was greater, time to peak filling rate was shorter, and rapid filling fraction was increased. When inspiration and expiration were compared, time to left ventricular peak filling rate was shorter (P = 0.05) on inspiration (118 /- 48 ms) than on expiration (168 +/- 35 ms) in patients with pericardial c onstriction No other measures differed between inspiration and expiration i n pericardial constriction, and left ventricular function was unaffected by respiration in the other groups. Time to left ventricular peak filling rat e vias 49 +/- 69 ms less on inspiration than on expiration in pericardial c onstriction and this difference was significantly different (P = 0.04) from that in patients with cardiac amyloid (34 +/- 58 ms greater), patients wit hout cardiac disease (2 +/- 69 ms greater) and patients with severe pulmona ry disease (19 +/- 63 ms less). In pericardial constriction, pericardial re section caused an increase in LVEF without a change in left ventricular dia stolic filling but abolished the differences present between inspiration an d expiration in time to left ventricular peak filling rate. This respirator y response in time to left ventricular peak filling rate may be valuable in the diagnosis of pericardial constriction. ((C) 2000 Lippincott Williams & Wilkins).