The central circulation in congestive heart failure non-invasively evaluated with dynamic positron emission tomography.

BACKGROUND

Positron emission tomography (PET) with [15O]-H2O-PET (WAT-PET) or [11C]-acetate (AC-PET) quantifies myocardial perfusion and oxidative metabolism, but routine clinical use is hampered by the need for additional investigations to assess cardiac performance.

OBJECTIVE

To apply classical tracer kinetics to dynamic PET could provide important haemodynamic parameters.

METHODS

First-pass PET data were used with indicator dilution techniques to measure stroke volume index (SVI). Early pulmonary retention of [11C]-acetate was converted to standard uptake values (SUV) (Lung(AC-SUV)). Regional lung water (rLW) content was computed from the WAT-PET scan at equilibrium. PET was compared with radionuclide angiography and echocardiography in patients with ischaemic cardiomyopathy with New York Heart Association class II (n = 10) or III (n = 18) congestive heart failure. Elderly male volunteers without heart disease (n = 11) underwent AC-PET as controls.

RESULTS

SVI with both tracers correlated in patients (r = 0.91, P<0.001, estimated standard error = 4 ml m(-2)) and with left ventricular ejection fraction (both tracers r>0.6, P<0.001). SVI was significantly different between all groups (ANOVA: P<0.001). Lung(AC-SUV) correlated with rLW (r = 0.78, P<0.001) and both were elevated in severe heart failure (P<0.05 for both). Elevated Lung(AC-SUV) was associated with a restrictive left ventricular (LV) filling pattern by Doppler echocardiography.

CONCLUSION

Dynamic PET with first-pass analysis and tracers of myocardial perfusion enables quantification of the haemodynamic consequences of LV systolic and diastolic dysfunctions in ischaemic cardiomyopathy and could be useful in the evaluation of the central circulation in heart failure.