A method of left ventricular ejection fraction estimation from cineangiocardiograms employing a special-purpose...

A special-purpose calculator is described which computes the left ventricular ejection fraction and end-diastolic volume (and thus stroke and end-systolic volumes) from single-plane cineangiocardiograms. A pair of manual callipers is used to convert the length information of angiographic projections into digital form for processing by the calculator. Volumes are estimated by means of a first order numerical integration method assuming circular cross-section. The angiograms of 42 patients were analysed using both the calculator and a conventional method. The results of the 2 methods correlated very closely (r = 0.99) with a slope within 1% of unity. The calculator is suggested as a practical and cheaper alternative to computer-based systems.