An alternative to enhanced external counterpulsation: A pilot study of ECG-driven sequential muscle stimulation

It is well documented that muscle stimulation may improve regional circulation. However, if this method can enhance systematic circulation remains unclear. In this pilot study, we designed an ECG-driven sequential muscle stimulation (ESMS) system and investigated if it is potentially capable of augmenting diastolic blood pressure as an alternative to enhanced external counterpulsation (EECP). We then used the proposed system to stimulate muscles of the hind limbs of a beagle dog at 36 V, and at the impulse frequency of 40 Hz, 70 Hz, and 100 Hz, respectively, synchronized with ECG ensuring the stimulation at diastole. We observed that ESMS increased diastole/systole pressure ratio of peak and area (DSp and DSa) evidently to 0.87 and 0.33, respectively, at 70 Hz. This encouraging result indicates that the ESMS may change hemodynamics and further study should be carried out to explore the stimulation pattern, target muscle selection, and the benefits of this method on systematic circulation.