REN and Left ventricular diastolic dysfunction: Studies have shown that in patients with chronic kidney disease, heart failure is mostly caused by the presence of left ventricular diastolic dysfunction, with aggravating comorbidities such as high blood pressure and coronary heart disease. A possible underlying mechanism may be the excessive activation of the renin-angiotensin-aldosterone system, which is known to be a determinant in the onset of profibrotic factors.