Relations between echocardiographic markers and glomerular and tubular kidney functions in cardiologic patients
Abstract
Background and aim: The close relation between the heart and kidney is controlled by many common pathogenetic pathways. The aim of this study was to determine a relationship between echocardiographic signs of systolic and diastolic heart dysfunction and the glomerular and tubular kidney functions. 123Pβvodní práceaktualityvnefrologii . ročník 26 . 2020 . číslo 4Methods: In a prospective study, we compared echocardiographic findings of 167 cardiologic patients (133 men, 34 women, mean age 62 y) without primary kidney diseases with parameters of the glomerular and tubular kidney functions.
In addition to eGFR estimated from the serum creatinine and cystatin C levels, we examined the kidney concentrating capacity after arginin-vasopressin administration. Results: There is the convincing relation between the echocardiographic findings and the functional ability of the two fundamental nephron segments, i.e., the glomeruli and tubules.
The echocardiographic signs characterizing systolic and diastolic heart dysfunction correlated both with the eGFR and the kidney concentrating capacity. Both glomerular filtration rate and kidney concentrating capacity were decreasing simultaneously with decreasing left ventricle ejection fraction.
The A (peak velocity of late diastolic filling due to atrial contraction), Ea (peak early diastolic mitral annular velocity), and E/A (E is the peak velocity of early diastolic filling) were the most frequent signs of the diastolic heart dysfunction connected with the glomerular filtration rate and kidney concentrating capacity decreases, while the E and DT (the deceleration time of E wave) were rarely connected with renal function decrease. The kidney concentrating capacity decreased simultaneously to the left atrium enlargement.
The left atrium area and left ventricle ESD (the end-systolic left ventricle diameter) were the echocardiographic structural parameters which correlated with the glomerular function estimated from cystatin C serum levels. The parallel decrease of eGFR and renal concentrating capacity accompanied both systolic and diastolic heart dysfunction.
We conclude that the cystatin C serum level and eGFR-cystatin C are the more sensitive correlates of a damaged kidney function than the serum creatinine level and eGFR-MDRD in the cardio-renal syndrome. Conclusion: The echocardiographic signs of both systolic and diastolic heart dysfunction are accompanied by a decrease of both eGFR and kidney concentrating capacity.
Cystatin C serum levels should be routinely assayed in patients with the cardio-renal syndrome.