A Chronic Method For Measuring Real-Time Pulse Wave Velocity In Conscious Rodents

Pulse wave velocity (PWV) is a measure of arterial stiffness and predictor of cardiovascular (CV) risk. PWV is calculated by recording the time it takes for an arterial pressure “pulse wave” to transit between two sites at a known distance apart. Prior to the advent of a small, dual pressure telemetry device (HD‐S21, DSI); PWV data were only attainable using acute measurement techniques in rodents. To investigate chronic, PWV measurement, two male rats (Sprague Dawley® Rat, Charles River Laboratory) were surgically implanted with the HD‐S21. The upstream catheter was placed in the left carotid artery and the downstream catheter was placed approximately 7.25cm away in the descending aorta. Following post‐surgical recovery, 24 hours of baseline arterial pressure and PWV data were collected from each animal. The next day, the rats were administered 30mg/kg of vasoconstrictor N ω ‐Nitro‐L‐arginine methyl ester hydrochloride (L‐NAME) via IP injection and data were recorded for 24 hours. Using 10 minute averaging intervals, 24 hours of baseline and post‐dose PWV data were compared. Average baseline PWV measurements of 286 and 357 cm/s increased sevenfold post L‐NAME dosing, resulting in PWV values as high as 1959 and 2561 cm/s due to increased vascular stiffness. This evaluation demonstrated that the HD‐S21 is a feasible tool for investigating chronic PWV measurements in small animal models.