Disturbance ofperipheral microvascular fluid permeability bytheonsetofatrioventricular asynchrony inpatients withprogrammable pacemakers

Background-In vitroandinvivoevidencesuggests thatatrial natriuretic peptidecan enhancefluidfluxfrom intravascular toextravascular compartments.Therelevance ofthistohuman pathophysiology remains unclear. Objectives-To determine whether acentralhaemodynamicchangeassociated withincreased plasmaconcentrations of atrialnatriuretic peptideproduces detectable changeinthecapillary filtrationcoefficient inaperipheral microvascular bed. Patients-12 patients withprogrammable dualchamberpermanent pacemakers. Methods-Calf capillary filtration coefficient (using amodified plethysmographic technique) andplasmaatrial natriuretic peptide concentrations weremeasured during atrioventricular synchronous and ventricular pacing. Results-Atrioventricular asynchrony wasassociated withhighermean (SD) concentrations ofatrial natriuretic peptide(231.9 (123.1) v53*5 (38.8) pg/ml) and anincreased mean(SD)calfcapillary filtration coefficient (4.2 (1.1) v 3-6(1.1) ml/min.mmHg.100ml x 10-'), butthere wasno correlation betweenthemagnitudeofthechangeinthesevariables in individual patients. Conclusions-The peripheral capillary filtration coefficient may changein response toaltered central haemodynamics.Atrialnatriuretic peptide remains onepotential candidate mechanism, but other factors arealsolikely tobeinvolved. (Heart 1996;75:509-512)