STUDY OF PREVALENCE OF AORTIC AND MITRAL CALCIFICATION IN CKD PATIENTS ON MAINTENANCE HAEMODIALYSIS AND ITS CORRELATION WITH BONE MINERAL PARAMETERS- A CROSS SECTIONAL STUDY

Introduction:

Chronic Kidney Disease (CKD) is rampant worldwide, with mortality rates 20 times greater than the general population. Cardiovascular complications account for over 40% of mortality and comprise well studied conditions like Coronary Artery Disease (CAD), cardiac failure and arrhythmias.

Cardiac Valvular Calcification (CVC), which occurs prematurely in CKD patients on Haemodialysis (HD) is an important complication. Studies on the prevalence and risk factors are few in number and show varying results. This study was undertaken to assess the prevalence of CVC in CKD patients on maintenance HD and correlate it with bone mineral parameters.

Methods:

A cross-sectional descriptive study was performed post-ethics committee approval on consenting CKD V patients undergoing thrice-weekly HD with HD vintage more than 3months. Period of study was for 2 years in the Department of Nephrology of a tertiary care Government hospital in South India.

Patients with pre-existing Rheumatic Heart Disease or known valvular abnormalities due to other causes were excluded. All patients underwent detailed history taking, clinical examination, blood investigations for Urea, Creatinine, Calcium, Phosphorous (Pi), intact Parathormone (iPTH), Vitamin D and Serum Alkaline Phosphatase (SAP) by standard analytical methods.

Sample size was calculated to be 245.86 by Cochran formula with 95% Confidence Interval (CI), alpha error of 0.05 and a prevalence of 20%.

Echocardiography was done on post-HD day with the patient maintaining dry weight and blood pressure under control. It was performed as per the recommendations of the American Society of Echocardiography by a single observer. Images were analyzed by an experienced cardiologist blinded to all clinical details. The machine was a digital commercial harmonic imaging ultrasound system with a 3.3 MHz phased-array transducer (Phillips IE33) with subjects lying in left decubitus position. CVC was defined as bright echoes of >1 mm on one or more cusps of the aortic/mitral valve, annulus or both.

Data was analyzed using IBM SPSS Version 26. Presence of CVC by echocardiography was the primary outcome variable. The association of CVC to socio-demographic characteristics and bone mineral parameters was assessed by chi-square test (univariate test). Multivariate analysis was performed to the variables found significant in univariate analysis (p<0.05) by Logistic Regression.

Results:

Baseline characteristics of 251 patients in this study are tabulated (Table 1). Mean age was 55 years. Mean HD vintage -2.01 years, Mean Se Ca- 8.5mg/dl and Mean Pi - 4.8mg/dl.  

Prevalence of CVC in this study was 37.8%. Prevalence of Mitral Valve Calcification (MVC) -26.7%, Aortic Valve Calcification (AVC) -21.5%, both MVC and AVC -10.36% and is depicted in Figure 1. 

Significance of association is tabulated in Table 2 and Table 3. 

Comparison with other studies is depicted in Table 4.

Conclusions:

1. The prevalence of CVC in the present study was 37.8%.  MVC was present in 26.7%, AVC was seen in 21.5%, and 10.36% of subjects displayed both.

2. Age≥65 years, female sex, hypoalbuminaemia and increased Calcium Phosphorus product were significantly associated with CVC. HD vintage, comorbidities, Serum Ca, Pi, PTH, SAP and Vitamin D level were not significantly associated with CVC.

I have no potential conflict of interest to disclose.

I did not use generative AI and AI-assisted technologies in the writing process.