The Langendorff System

The IH-Series Ex Vivo Perfused Heart Systems always start as a Langendorff system. This means a configuration solely for retrograde perfusion down the aorta (toward the heart). In this mode, the aortic valve prevents the perfusate (nutrient solution) from entering the left ventricle, but the coronary arteries are perfused via the coronary ostia which are located just above the valve, thus maintaining the viability of the heart muscle. Perfusate drains as effluate from the coronary circulation via the coronary sinus and pulmonary artery tends to drip from the apex of the heart making it easily available for collection. The IH system configured in this way provides an excellent platform for basic applications such as cardiomyocyte isolation as well as for physiological monitoring using the robust Langendorff assay whereperfusions of several hours are typical.

The modular nature of the IH-Series allows for initial integration or later upgrade with the Working Heart (also known as Ejecting Heart) perfusion pathway. This enables orthograde perfusion: entering the left atrium, flowing through the left ventricle and exiting the aorta. In this way, a more physiological assay of ventricular contractility is possible as the left ventricle is now fully-ejecting and performing pressure-volume and acceleration work. In order to fully exploit this advantage, the IH-Series includes a specialized pathway which easily allows introduction of a Pressure (LVP) or Pressure Volume (LV-PV) catheter directly into the left ventricle via the aorta, rather than via apical puncture.

The Biventricular Working Heart system  allows for ex vivo studies of diseases characterized by pulmonary vascular dysfunction and right heart pathophysiology. The system employs unique flow resistance and compliance chambers to faithfully mimic the in vivo cardiac preloads and afterloads for both normal and diseased states. In addition to the ejecting left heart, which is now supplying perfusate to the coronaries and thus maintaining heart muscle viability, the right heart is also performing the low pressure ejection, whereby the perfusate enters the right atrium, flows into the right ventricle and exits through the pulmonary artery. Additional measurements of Right Ventricular Pressure (RVP) or Right Ventricular Pressure-Volume (RV-PV) can now be taken independently or simultaneously with LVP/LV-PV.