The relationship between aortic stiffness, health related quality of life and post-operative organs recovery (cardiac, renal and cognitive) following aortic valve replacement

Background: Aortic stiffness as measured by pulse wave velocity (PWV) is a predictor of cardiovascular disease and other outcomes in different diseased and healthy populations, independent of traditional risk factors. The relationships between PWV measurement, global functional outcome and injury to the brain, kidney, and heart have never been examined in cardiac surgery patients. Objective: The objective of this project was to assess the relationship between aortic stiffness and health related quality of life (QoL), cognitive function, acute kidney injury (AKI), and cardiac function in patients undergoing aortic valve replacement (AVR). Methods: Aortic PWV, QoL, cognitive function, left ventricular (LV) function and NYHA class were assessed pre- and post-operatively (409 ± 159 days). The brain injury biomarker, N-methyl-D-aspartate receptor antibody (NR2Ab), was measured pre-operatively only. The biomarker of myocardial strain, B-type natriuretic peptide (BNP), and the novel AKI biomarker, neutrophil gelatinase-associated lipocalin (NGAL), were measured pre-operatively, and at 3 h and 18-24 h post-CPB. Results: Fifty-six patients (16 females; mean age, 71 ± 8.4 years) were included in this study, of which 50 (89%) patients attended the follow-up visit. No relationship was found between the degree of aortic stenosis (AS) and PWV, and AVR had no effect on aortic stiffness post-operatively. QoL and NYHA class significantly improved, while cognitive function did not deteriorate after AVR. High PWV is independently related to poorer QoL, cognitive function levels and NYHA class both pre- and post-operatively. PWV was not related to LV function, BNP or NGAL levels, but it was independently related to the level of NR2Ab. PWV did not correlate with AKI which was developed in 30% of the cases. Early post-operative plasma level of NGAL is the earliest predictive marker of post-operative AKI and the need for early medical renal intervention. Pre-operative BNP level was significantly and negatively correlated with pre-operative LV function, AS (valve area), and NYHA class in the post-operative follow-up period. Conclusion: In AVR patients, PWV is independently related to global functional status, cognitive function and brain injury biomarkers, but is not related to AKI or myocardial strain.Open Acces

A rare case of suture material obstructing the closure mechanism of a prosthetic aortic valve: a case report

Prosthetic aortic valve dysfunction presenting as aortic regurgitation is a complication of mechanical valve replacement. We describe a case of late valve dysfunction caused by an annular suture of excessive length obstructing the closure mechanism of a bileaflet prosthetic valve

Aortic stiffness as a marker of cardiac function and myocardial strain in patients undergoing aortic valve replacement

Background: Cardiac function and myocardial strain are affected by cardiac afterload, which is in part due to the stiffness of the aortic wall. In this study, we hypothesize that aortic pulse wave velocity (PWV) as a marker of aortic stiffness correlates with conventional clinical and biochemical markers of cardiac function and perioperative myocardial strain in aortic valve replacement (AVR). Methods: Patients undergoing AVR for aortic stenosis between June 2010 and August 2012 were recruited for inclusion in this study. PWV, NYHA class and left ventricular (LV) function were assessed pre-operatively. PWV was analysed both as a continuous and dichotomous variable according to age-standardized reference values. B-type natriuretic peptide (BNP) was measured pre-operatively, and at 3 h and 18-24 h after cardiopulmonary bypass (CPB). NYHA class, leg edema, and LV function were recorded at follow-up (409 ± 159 days). Results: Fifty-six patients (16 females) with a mean age of 71 ± 8.4 years were included, with 50 (89%) patients completing follow-up. The NYHA class of PWV-norm patients was significantly lower than PWV-high patients both pre- and post-operatively. Multiple logistic regression also highlighted PWV-cut off as an independent predictor of NYHA class pre- and post-operatively (OR 8.3, 95%CI [2.27,33.33] and OR 14.44, 95%CI [1.49,139.31] respectively). No significant relationship was observed between PWV and either LV function or plasma BNP. Conclusion: In patients undergoing AVR for aortic stenosis, PWV is independently related to pre- and post-operative NYHA class but not to LV function or BNP. These findings provisionally support the use of perioperative PWV as a non-invasive marker of clinical functional status, which when used in conjunction with biomarkers of myocardial strain such as BNP, may provide a holistic functional assessment of patients undergoing aortic valve surgery. However, in order for PWV assessment to be translated into clinical practice and utilised as more than simply a research tool, further validation is required in the form of larger prospective studies specifically designed to assess the relationship between PWV and these functional clinical outcomes