The purpose of this study was to present a protocol for visualizing lymphatic flow in patients with heart failure (HF) by using indocyanine green fluorescence lymphography. We studied 37 subjects: 20 patients with acute heart failure (AHF) and lower limb edema, 7 patients with chronic heart failure (CHF) without lower limb edema, and 10 control subjects (no HF, no limb edema). All subjects were assessed at rest, and 11 subjects (6 control and 5 with CHF) were assessed again after a 10-minute walk. The lymph flow was visualized in all selected patients without complications. At rest, there was either no lymph flow or minimal lymph flow in all control subjects and patients with CHF, whereas the majority of patients with AHF demonstrated significant lymph flow. This study describes a new method to visualize/assess lymphatic flow in patients with HF, allowing for continuous, real-time tracking of lymphatic flow in the lower extremity.
For the detection of ICG fluorescent signal, we used IC-Flow Imaging System produced by Diagnostic Green. The camera allows to visualize the lymphatic vessels filled with ICG in real time, therefore allowing to follow and visualize the lymph drainage. IC-Flow Imaging System allows for changing the aperture to adjust to the environment in which the measurements are taking place, as well as having the ability to take pictures and record videos during the examination. The protocol presented in this study provides a new method for visualizing and assessing peripheral lymphatic flow. It allows for continuous, real-time tracking of lymphatic flow and enables examination of all lymphatic drainage pathways in the lower extremity. Although this method has some limitations, including the inability to perform serial flow assessments within a short period of time, it has several advantages and is safe and easy to perform. Overall, this protocol provides a valuable method for lymphatic drainage assessment in patients with HF. It could potentially help to understand the role of the lymphatic system in the pathophysiology of HF and, as a result, could aid in developing new ways of treatment for peripheral edema in those patients.
https://www.sciencedirect.com/science/article/pii/S2452302X24000950