Whatever Happened to Measuring Ventricular Contractility in Heart Failure?

Abstract

Attempts have been made to assess and measure ventricular contractility in patients and whether it can be used to identify heart failure. Due to the assumption that if the contractility of all the muscle fibres in a heart were lower, could it be called heart failure? Early attempts involved the assumption of a model of muscle that had a contractile unit in series with an elastic element, but this was found to be incorrect. Further attempts applied the series elastic model but this model also proved challenging. However, one method has assessed changes in contractility in a given patient, in response to an intervention, but could not compare contractility in a patient with heart failure with a normal person. End-systolic pressure-volume (ESPV) is regarded as a more correct index of contractility and this method was used to confirm changes in contractility from beat to beat during AF, showing results that end-systolic volume varied and indicating a shift of ESPV from beat to beat. This review will discuss the difficulty in measurement, the complicated nature of myocardial fibre orientation and hypertrophy, and whether myocardial contractility failure precipitates increased global heart failure.