DMVA is a non-blood contacting MCS device that augments both systolic AND diastolic function. Notably, the device is recognized by the AHA as having significant potential for resuscitation). DMVA should be distinguished from cardiac compression, which merely augments systolic ventricular function (also termed Direct Cardiac Compression or DCC). A weakness of DCC is that it limits the amount of diastolic filling.  Conversely, DMVA augments diastolic filling by the vacuum facilitated seal maintained between the pneumatically actuated diaphragm of the DMVA device and the heart’s epicardial surface.  The ventricular cavities are in effect, “pulled” open during diastolic actuation. This is demonstrated by significant increases in the left ventricle (LV) diastolic -dP/dT (negative change in pressure/change in time) and myocardial strain rates during DVMA support.  DMVA’s effect on systolic function is more easily appreciated when describing the fundamentals of cardiac actuation.  Combining systolic and diastolic actuation explains why DMVA is so effective in supporting the failing, or asystolic heart.

The importance of overcoming diastolic dysfunction, or impaired filling, cannot be over-emphasized.  Also important is DMVA’s unique feature of rapid installation.  This feature provides the rationale for use in emergency settings such as sudden death or acute cardiovascular collapse.  The time required for device installation is strictly dependent on surgical exposure of the heart.  Documented installation times in repeated animal experimental (one to three minutes) and clinical (two to five minutes) applications verify this unique attribute. Application simply requires device positioning over the heart’s apex; the device engages itself on the ventricular surface as the vacuum delivered via its apical port accumulates. Cardiac support is dictated by the drive system’s cycled pneumatic forces that control the delivery of said forces to the heart surface, resulting in the return of physiologic pulsatile blood flow.