Comparison of CT acquired valvular calcification scores in hemodialysis vs peritoneal dialysis patients undergoing open heart surgery

Abstract

Abstract Background Several factors have been identified as independent risk factors for cardiac valvular calcification (CVC), including but not limited to age, inflammatory conditions, loss of calcification inhibitors, and dysregulated bone mineral metabolism. However, data is scarce regarding which dialysis modality portends more severe CVC. Purpose Our aim was to compare the degree of valvular calcification in hemodialysis (HD) and peritoneal dialysis (PD) patients prior to open heart surgery (OHS) using a computed CT calcium score. Methods Dialysis patients who underwent OHS at our institution from 2009–2019 who had a pre-surgical cardiac CT were grouped according to duration of dialysis modality prior to their surgical date. There were two study cohorts to evaluate outcomes of interest: mitral and aortic calcification. We included the first surgical record per patient for patients undergoing isolated CABG, or CABG+valve surgery (repair or replacement), or valve-only surgery (repair or replacement). To evaluate mitral calcification, we excluded any patients undergoing any mitral valve surgery (repair or replacement). We also excluded patients with a history of mitral valve repair/replacement. To evaluate aortic calcification, we excluded any patients undergoing any aortic valve surgery (repair or replacement). We also excluded patients with a history of aortic valve repair/replacement. Mitral annular and aortic valvular calcification were assessed using the Agatston score. Logistic regression was performed to test for the association of PD and HD cumulative dialysis duration with presence of valvular calcification. Results A total of 296 patients met inclusion criteria for at least one of the strata in our study. Of those, 214 met inclusion for the mitral strata, and 166 met criteria for the aortic strata (Table 1). In the logistic regression model for the mitral strata, age and female sex were associated with higher odds of presence of mitral calcification (Figure 1). Cumulative years on PD and cumulative years on HD were not significantly associated with presence of mitral calcification. In the logistic regression model for the aortic strata, age was associated with higher odds of presence of aortic calcification, while female sex was associated with lower odds (Figure 1). Cumulative years on PD and cumulative years on HD were not significantly associated with presence of aortic calcification. Conclusion Presence of mitral and aortic calcification for patients undergoing OHS was not significantly associated with cumulative length of PD or HD after adjusting for age and gender, suggesting that there may be more factors at play in the progression of valvular calcification in end stage renal disease patients than what was previously thought. Funding Acknowledgement Type of funding sources: None.