The dimensionless Frank-Starling Gain index, calculated as the ratio of end-systolic to end-diastolic force-length relation slopes, effectively quantifies pre-load recruitable contractile reserve.
The Frank-Starling Gain index provides a dimensionless measure of active force recruitability in cardiomyocytes, avoiding errors related to sample cross-section normalization and capturing both end-systolic and end-diastolic mechanics.
This paper briefly recapitulates the Frank-Starling law of the heart, reviews approaches to establishing diastolic and systolic force-length behaviour in intact isolated cardiomyocytes, and introduces a dimensionless index called 'Frank-Starling Gain', calculated as the ratio of slopes of end-systolic and end-diastolic force-length relations. The benefits and limitations of this index are illustrated on the example of regional differences in Guinea pig intact ventricular cardiomyocyte mechanics. Potential applicability of the Frank-Starling Gain for the comparison of cell contractility changes upon stretch will be discussed in the context of intra- and inter-individual variability of cardiomyocyte properties.
Bollensdorff et al. (Thu,) conducted a review in Assessment of contractility in intact ventricular cardiomyocytes. Frank-Starling Gain (FSG) index vs. End-systolic force-length relation (ESFLR) alone was evaluated on Frank-Starling Gain (FSG) index. The dimensionless Frank-Starling Gain index, calculated as the ratio of end-systolic to end-diastolic force-length relation slopes, effectively quantifies pre-load recruitable contractile reserve.