Cardiovascular Alterations and Structural Changes in the Setting of Chronic Kidney Disease: a Review of Cardiorenal Syndrome Type 4

Abstract

Cardiovascular and renal physiology are interrelated. More than a decade ago this was codified in guidelines defining the five subtypes of the cardiorenal syndrome. Morbidity and mortality for those with the cardiorenal syndrome is high compared to demographically matched individuals without cardiorenal disease, acute or chronic. The focus of this review will be the epidemiology, the impact of chronic kidney disease on cardiac structure and function, and associated clinical symptoms, outcomes, and potential treatments for patients with chronic reno-cardiac syndrome, or cardiorenal syndrome type 4. Cardiac structural changes can be profound and are described in detail both at a cellular and physiologic level. Integrating therapies for the treatment of causative or resulting comorbidities may ultimately slow progression of both cardiac and renal disease as well as minimize symptoms and death. Keywords Chronic renal insufficiency · Cardiorenal syndrome · Left ventricular hypertrophy · Fibrosis · Arterial stiffness Abbreviations ACR Albumin creatinine ratio ADQI Acute dialysis quality initiative AKI Acute kidney injury AMI Acute myocardial infarction CKD Chronic kidney disease CVA Cerebral vascular accident CVD Cardiovascular disease eGFR Estimated glomerular filtration rate ESKD End-stage kidney disease FGFR Fibroblast growth factor receptor FGF23 Fibroblast growth factor-23 HD Hemodialysis HF Heart failure HFpEF Heart failure with preserved ejection fraction HFrEF Heart failure with reduced ejection fraction IL Interleukin KDIGO Kidney disease improving global outcomes LDL Low-density lipoprotein LVEF Left ventricular ejection fraction LVH Left ventricular hypertrophy MI Myocardial infarction MMP Matrix metalloproteinases RAAS Renin-angiotensin-aldosterone system SCD Sudden cardiac death TGFβ Transforming growth factor beta TIA Transient ischemic attack TNFα Tumor necrosis factor alpha USRDS United States renal data system Methods The predominant source of information was obtained through Pub-Med searching terms including mesh terms (keywords as listed above and here: Chronic renal insufficiency, Cardiorenal syndrome, Left ventricular hypertrophy, Fibrosis, Arterial stiffness. The latter three terms were linked via "and" to the first mesh terms and "renal disease." The citations of individual papers were then reviewed for additional primary source documentation. In addition, for epidemio-logic data, we utilized data directly from the United States Renal Data System (https:// www. usrds. org/ annual-data-report/).