Calcification in the cardiac valves and aorta portends worse survival and progresses faster in patients with end-stage kidney disease (ESKD), new research confirms.
In a study of 434 patients receiving hemodialysis (HD), 27.2% of patients displayed mitral valve calcification (MVC) and 31.8% aortic valve calcification (AVC) on echocardiography. The group with vs without cardiovascular calcification had significantly higher all-cause and cardiovascular mortality rates, Ning Cao, MD, of General Hospital of Northern Theater Command, Liaoning, China, and colleagues reported in BMC Nephrology. In multivariate regression analyses, the presence of MVC and AVC was significantly associated with 1.5- and 1.4-fold increased risks for all-cause mortality and 2.3- and 2.4-fold increased risks for cardiovascular mortality, respectively. Left atrial dimension also significantly correlated with all-cause and cardiovascular death. Left ventricular mass index (LVMI) was an independent risk factor in univariate but not multivariate Cox regression.
MVC may lead to mitral regurgitation, stenosis, or both, whereas AVC can cause aortic stenosis, the investigators noted.
“Our findings may have important clinical implications,” Dr Cao’s team wrote. “[Cardiovascular calcification] on routine echocardiography should not be overlooked and can be used for risk assessment in maintenance HD patients. Moreover, it can help identify patients who are appropriate for intensive medical treatment to reduce cardiovascular events.”
Patients taking oral active vitamin D had significantly lower risks of cardiovascular and all-cause mortality, the investigators reported. Activated vitamin D treatment possibly slows left ventricular hypertrophy, improves left ventricular diastolic function, and reduces episodes of heart failure, they suggested.
In a second study, researchers examined progression of aortic calcification in 150 patients with stage 4-5 chronic kidney disease transitioning to dialysis or transplantation or continuing conservative care. The median abdominal aortic calcification (AAC) score significantly increased from 4.8 before renal replacement therapy or conservative care to 8.0 at 3 years after the transition, with no difference among treatment modalities, Roosa Lankinen, MD, of University of Turku, Turku, Finland, and colleagues reported in Kidney and Blood Pressure Research.
The annual rate of AAC increase was significantly associated with a 1.4-fold increased risk for mortality and, in transplant recipients, a longer time on the transplant waiting list, the investigators reported. The annual increase in AAC was independently associated with mean LVMI and serum phosphorus.
“These findings suggest that at least in the early years following kidney transplantation, the [vascular calcification] process continues similarly to that on maintenance dialysis or without RRT altogether.”
A systematic review published in the Journal of the American Society of Nephrology of 77 clinical trials involving 6898 participants examined therapies to slow vascular calcification in patients with chronic kidney disease including those receiving renal replacement therapy. Therapies involving magnesium or sodium thiosulfate showed the most promise in reducing vascular calcification progression, Nigel Toussaint, MD, of The University of Melbourne, Parkville, Australia, and colleagues reported. Other possible therapies warrant additional study, including phosphate binders, dialysate calcium adjustment, vitamin K therapy, calcimimetics, and antiresorptive agents.
Bai J, Zhang X, Zhang A, et al. Cardiac valve calcification is associated with mortality in hemodialysis patients: a retrospective cohort study. BMC Nephrol. 23:43. doi:10.1186/s12882-022-02670-5
Lankinen R, Hakamäki M, Hellman T, Koivuviita NS, Metsärinne K, Järvisalo MJ. Progression of aortic calcification in stage 4-5 chronic kidney disease patients transitioning to dialysis and transplantation. Kidney Blood Press Res. 2022;47(1):23-30. doi:10.1159/000518670
Xu C, Smith E, Tiong M, Ruderman I, Toussaint N. Interventions to attenuate vascular calcification progression in chronic kidney disease: a systematic review of clinical trials. J Am Soc Nephrol. Published online March 1, 2022. doi:10.1681/ASN.2021101327