Ventricular mechanical dyssynchrony and resynchronization therapy in heart failure: a new indication for Fourier analysis of gated blood-pool radionuclide ventriculography.

In patients with decreased left ventricular ejection fraction and conduction disease, ventricular mechanical dyssynchrony has been demonstrated. To date, resynchronization by biventricular pacing is increasingly used since it improves ventricular function and exercise capacity in patients with heart failure. To optimize and evaluate the effect of resynchronization therapy and to identify patients who may benefit from biventricular pacing the assessment of left ventricular synchronicity is essential. Therefore, a non-invasive and reproducible technique to obtain information on ventricular synchrony is clinically valuable. In this review, the technical background and the role of phase analysis of gated blood-pool nuclear ventriculography in the assessment of ventricular mechanical synchrony, especially in heart failure patients subjected to biventricular pacing, will be discussed.