a system capable of testing a range of cardiovascular conditions
Real-time control, monitoring, and data display reassures the user that the system is functioning properly. Independent adjustment of systolic and diastolic pressures, waveform-tuning capabilities, and easy manipulation of heart rate, flow rate, and duty cycle are some of the improvements over standard peristaltic-pump flow loops.
The standard vascular chamber houses up to five vessels held in parallel conditions during experimentation. If more/less vessels are desired, unused lines can be closed off or a custom chamber can be used. Its optically transparent design allows for visualization during experimentation. Custom vessel fittings allow a range of vessel diameters, lengths, and thicknesses to be used. Special clamps are used to hold the vessel in place without damaging tissue. Additional customization can be provided to facilitate custom experimental protocols such as balloon angioplasty or stent deployment.
Clamps directly affect the pressure in ways such as raising/lowering the systolic pressure and raising/lowering the diastolic pressure.
The flow meter measures the flow through the entire system. The turbine’s rotations are measured by an infrared sensor which must be calibrated using a known K-factor.
Two pressure transducers are provided with each system. One of which measures the inflow pressure seen by each vessel, while the other measures the pressure outside each vessel. Alternatively, the second pressure transducer may be attached to the outflow manifold to measure pressures directly after the vessels.
The inflow manifold and the outflow manifold are used to distribute the flow across all five vessels. The outflow manifold has an extra port that is commonly closed off, but may be used if post-vessel pressure readings are desired instead of outer-vessel readings.
The vessel fittings allow for adjustments in both the length and diameter of the vessel, ranging from 1.78-5.94 mm inner diameter and up to 9 cm lengths. Alternate components facilitate custom experimental protocols, including balloon angioplasty or stent deployment.
The dampener contains a small volume of air used to dampen the cyclical pulsations of fluid and pressure caused by the peristaltic pump functioning.
The compliance chamber holds a volume of air that is used to maintain back-pressure on the vessels. Increasing the volume of air slows the release of pressure, raising the diastolic pressure. Conversely, decreasing the volume of air quickens the release of pressure, lowering the diastolic pressure. This compliance chamber has been specially designed to use a minimum amount of culture media (~5-10 mL) across all volumes of air used.
The reservoir is used to allow sterile gas exchange. It holds enough volume of culture media for the variance in fluid volumes seen during pressurization of the system, but has been specially designed to maintain function while using a minimal amount of culture media (~5-10 mL).
The pinch valve is used to create the heartbeat. Adjusting the number of milliseconds that the pinch valve is on and off will adjust the heart rate and proportion of the duty cycle dedicated to flow.
The controls box contains all Aptus control and monitoring equipment for your flow loop system.
The peristaltic pump drives the flow, which controls the volumetric flow rate.