Myocardial Contractility in the Stress Echo Lab
Myocardial Contractility in the Stress Echo Lab
In recent years, the FFR has been transferred from the experimental lab to the clinical arena, and in particular within the clinical arena from the cardiac catheterization to the stress echo lab, with an obvious step-up in interest and applicability. Ideally, the non-invasive, imaging-independent, objective assessment of FFR would greatly further enhance its practical appeal (Figure 1). A new cutaneous force-frequency relation recording system has recently been validated in the stress echo lab, based on heart sound amplitude and timing variations at increasing heart rates. Force-frequency relation recording is feasible with a single precordial vibration sensor connected to a standard ECG monitoring electrode, and quantitatively documents left ventricular contractility changes in a totally automatic, operator-independent fashion. Sensor built force-frequency relation is strictly related to the standard stress echo built FFR. Echocardiography uses artificially generated cardiac reflections. The isovolumic systolic force sensor simply records naturally generated heart vibrations. The FFR is built online. The system is portable, and the remote transmission of the FFR slope and shape is feasible and simple. This approach is extendable to daily physiological exercise and could be potentially attractive in home monitoring systems. To fully establish the advantages and limits of this new method, comparisons with left ventricular pressure-volume loops in humans and multicenter study data are needed.
Future Developments: Imaging-independent, Sensor-based Contractility
In recent years, the FFR has been transferred from the experimental lab to the clinical arena, and in particular within the clinical arena from the cardiac catheterization to the stress echo lab, with an obvious step-up in interest and applicability. Ideally, the non-invasive, imaging-independent, objective assessment of FFR would greatly further enhance its practical appeal (Figure 1). A new cutaneous force-frequency relation recording system has recently been validated in the stress echo lab, based on heart sound amplitude and timing variations at increasing heart rates. Force-frequency relation recording is feasible with a single precordial vibration sensor connected to a standard ECG monitoring electrode, and quantitatively documents left ventricular contractility changes in a totally automatic, operator-independent fashion. Sensor built force-frequency relation is strictly related to the standard stress echo built FFR. Echocardiography uses artificially generated cardiac reflections. The isovolumic systolic force sensor simply records naturally generated heart vibrations. The FFR is built online. The system is portable, and the remote transmission of the FFR slope and shape is feasible and simple. This approach is extendable to daily physiological exercise and could be potentially attractive in home monitoring systems. To fully establish the advantages and limits of this new method, comparisons with left ventricular pressure-volume loops in humans and multicenter study data are needed.