This study, adhering to the rigorous standards defined by the FDA and set by the American Society for Testing and Materials, utilized two identical in vitro blood circulatory loops to compare the hemolytic effects of these devices under identical hemodynamic, temperature, and all test conditions.
The published research performed at Texas Heart Institute (THI) involved testing five Whisper™ devices at 10,000 RPM and a comparator Impella CP® at approximately 44,133 RPM, necessary to match the flow rate of the Whisper™. The Whisper™ device was tested at 10,000 RPM according to FDA guidelines but typically operates at 7,000 to 7,500 RPM, maintaining native flow and natural heart pulsatility and achieving accretive flow rates. Conversely, intracardiac devices that redirect blood from the left ventricle (LV) to the aorta provide non-pulsatile flow. A separate study at THI showed that Whisper™ can generate a flow rate of up to 6.8 liters per minute.
Analysis was conducted using the tetramethylbenzidine method to measure plasma free hemoglobin, a key indicator of hemolysis. The findings revealed that the Whisper™ not only had a lower change in plasma free hemoglobin but also significantly outperformed the Impella CP® in both the normalized index of hemolysis and the modified index of hemolysis.
These results suggest that the Whisper™ device could potentially offer a far safer alternative in clinical settings where high rotational speeds are necessary, thereby reducing the risk associated with hemolysis. This may play a critical factor when selecting devices for therapeutic durations exceeding even just one hour before potential acute kidney injury (AKI) caused by high levels of hemolysis.
While this study utilized the Johnson & Johnson (Abiomed) Impella CP® device, it is relative to all "micro-axial" pump designs with small annulus pumps with larger shear attributes and housings that generate geometric harmonics, both important factors beyond revolutions per minute that all contribute to mechanical hemolysis. This study not only underscores Whisper's advanced design and performance but also establishes critical benchmarks that will aid in the development and evaluation of future pMCS devices.
About Second Heart Assist Inc:
Second Heart Assist Inc. is developing a temporary percutaneous mechanical circulatory support (MCS) system that utilizes a stent cage fitted with a motorized impeller to aid in providing circulatory support throughout a patient's body. The system is intended for use in patients hospitalized with acute decompensated heart failure (ADHF) and who develop diuretic resistance with persistent congestion (cardio-renal syndrome (CRS), and/or cardiogenic shock (CS), and those in need of prophylactic hemodynamic support during high-risk percutaneous coronary intervention (HRPCI).
