Cardiac and arterial interactions in end-stage renal disease

Abstract

Although cardiac hypertrophy is a frequent complication of end-stage renal disease (ESRD), relatively little is known about large arterial geometry and function in vivo in these patients, and the relationship between arterial changes and cardiac hypertrophy is unknown. Common carotid artery (CCA) intima-media thickness and internal diameter and left ventricular geometry and function were determined by ultrasound imaging in 70 uncomplicated ESRD patients and in 50 age-, sex-, and blood pressure-matched controls. Arterial distensibility and compliance were determined from simultaneously recorded CCA diameter and stroke changes in diameter and CCA pressure waveforms, obtained by applanation tonometry, and also by the measurement of carotid-femoral pulse wave velocity. Compared with control subjects, ESRD patients had greater left ventricular diameter (P < 0.01), wall thicknesses and mass (P < 0.001), increased CCA diameter (6.25 +/- 0.87 vs. 5.55 +/- 0.65 mm; P < 0.001), larger CCA intima-media thickness (777 +/- 115 vs. 678 +/- 105 microns; P < 0.001) and intima-media cross-sectional area (17.5 +/- 4.5 vs. 13.4 +/- 3.3 mm2; P < 0.001). In uremic patients, arterial hypertrophy was associated with decreased CCA distensibility (17.8 +/- 8.8 vs. 24.0 +/- 12.7 kPa-1.10(-3); P < 0.001) and compliance (5.15 +/- 2 vs. 6.0 +/- 2.5 m2.kPa-1.10(-7); P < 0.05), accelerated carotid-femoral pulse wave velocity (1055 +/- 290 vs. 957 +/- 180 cm/seconds; P < 0.001), early return and increased effect of arterial wave reflections (20.5 +/- 15.4 vs. 9.2 +/- 18.4%; P < 0.001). The latter phenomenons were responsible for increased pulsatile pressure load in CCA (58.3 +/- 21 vs. 48 +/- 17 mm Hg; P < 0.01) and were associated with a decreased subendocardial viability index (157 +/- 31 vs. 173 +/- 30%; P < 0.001). The CCA diameter was correlated with the left ventricular diameter (P < 0.01), and a significant correlations existed between CCA wall thickness or CCA intima-media cross-sectional area and left ventricular wall thicknesses and/or left ventricular mass (P < 0.01). In multivariate analysis, these relationships were independent regarding age, sex, blood pressure and body surface area. The present study documents parallel cardiac and vascular adaptation in ESRD, and demonstrates the potential contribution of structural and functional large artery alterations to the pathogenesis of left ventricular hypertrophy and functional alterations.