Pulse Wave Velocity as a Predictor for Postoperative Cardiovascular Events

Vascular stiffness increases as a person ages, due to the repetitive stress that is put on the vascular system which causes changes in the elasticity of the vessel walls. The increased stiffness of the arteries puts added stress on the circulatory system. This rise in stiffness has been shown to be associated with an increased risk of cardiovascular events, in both presumably healthy patients, as well as elderly patients The current method for assessing perioperative cardiac risk is the Goldman's Revised Cardiac Risk Index (RCRI). This method, however, does not include a direct measurement of arterial stiffness. Applanation tonometry is a non-invasive technique that has been shown to reliably provide indices of arterial stiffness While the use of applanation tonometry has been widely studied in general medicine, it is has not been studied for pre-operative risk assessment in surgical patients. The purpose of this investigation is to examine whether aortic stiffness is an independent risk factor for developing cardiovascular related adverse events in patients who are having major surgery under general anesthesia. Applanation tonometry will be performed on the right carotid and femoral arteries to assess carotid-femoral pulse wave velocity, a surrogate for aortic stiffness. (SphygmoCor system, AtCor Medical, Sydney, Australia). The measurement will be obtained before induction of general anesthesia in the presurgical area. Patients' medical history, intraoperative hemodynamics, and any postoperative complications will be recorded to determine significant correlations and relationships. This information will potentially help identify future patients that might be at greater risk of developing an adverse cardiovascular event following their surgical procedure.