Passive Retrograde Cerebral Perfusion (PRCP)Following Routine Cardiac Valve Surgery Eliminates the Risk of Peri-Operative Cerebral Vascular Accidents
A post-operative neurologic event, in the open heart patient, is second only to a low cardiac output state as the complication most highly associated with in-hospital death. In the elderly, the incidence of a cerebral vascular accident (CVA), following cardiac valve surgery in particular, may be as high as 11%. This may be the result of either macro-embolism (air/debris) or inadequate perfusion pressure. We have previously demonstrated in a cohort of valve patients that upon discontinuation of cardiopulmonary bypass (CPB) the risk of peri-operative stroke could virtually be eliminated by opening a shunt for three minutes between the arterial (in-flow) and venous (out-flow) limbs of the extra-corporeal circuit. This phenomenon, passive retrograde cerebral perfusion (PRCP), reverses blood flow in the middle cerebral arteries. In this study, we have further evaluated PRCP in an older population with more co-morbidities to determine if there exists any limitations to the procedure. One hundred eight consecutive patients with a mean age of 68 years (range 38- 90 years) underwent elective valve repair/replacement and PRCP was instituted. The mean shunt flow rate was 2.6 Liters/minute (L/m) with a range of 1.9–4.0 L/m. The incidence of peri-operative CVA (30 day) was 0% (0/108). The incidence of CVA in published retrospective data is 0.7–3.8% and 4.8–5.2% in prospective data. In this report, we confirm that PRCP following valve surgery eliminates the risk of peri-operative CVA. We frequently perform the procedure as an adjunct to on-pump coronary artery bypass surgery in the context of suspected intra-ventricular thrombus or an artheromatous ascending aorta. We hypothesize that the principles of PRCP could easily be applied to Port surgery now that the instrumentation is trans-thoracic since aortic occlusion is still performed with an intra-vascular device.