Electrocardiographic abnormalities and uremic cardiomyopathy.
BACKGROUND
Progressive renal disease is associated with an increased risk of cardiovascular death, specifically sudden death. We investigated the link between uremic cardiomyopathy, QT interval and dispersal, and arrhythmias (by ambulatory ECG monitoring) in patients at different stages of progressive renal disease.


METHODS
In a cross-sectional study we investigated 296 patients with nondiabetic renal disease (53 transplant recipients, 55 hemodialysis patients, and 188 throughout the range of chronic renal failure). Patients underwent echocardiography, ECG, and ambulatory blood pressure and ECG monitoring.


RESULTS
Left ventricular mass was increased from the earliest stages of renal disease (near-normal renal function), the predominant pattern being eccentric left ventricular hypertrophy (LVH). There was a progressive increase in LVH with loss of renal function, so that more than 80% of patients on renal replacement therapy have LVH, the dominant pattern being concentric LVH. The prevalence of diastolic dysfunction increased in parallel with changes in left ventricular mass but systolic dysfunction and ventricular dilatation did not. Increased QT interval and QT dispersal were associated with poor renal function (maximal in dialysis patients), and were linked to LVH and other echocardiographic abnormalities. Arrhythmias were uncommon on ambulatory recording but were more common with poor renal function, in the presence of uremic cardiomyopathy, and increased QT interval and dispersal.


CONCLUSIONS
LVH is present from the earliest stages of progressive renal disease. This, and other forms of uremic cardiomyopathy, is linked to increased QT interval and dispersal, and with minor rhythm abnormalities, providing a link with the high risk of sudden death in this population.
Stewart
Graham A
GA
Division of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow, United Kingdom.
Gansevoort
Ron T
RT
Mark
Patrick B
PB
Rooney
Esther
E
McDonagh
Theresa A
TA
Dargie
Henry J
HJ
Stuart
R
R
Rodger
C
C
Jardine
Alan G
AG
D000328:Adult; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000209:etiology / Q000503:physiopathology; D009202:Cardiomyopathies / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology*; D003430:Cross-Sectional Studies; D016757:Death, Sudden, Cardiac / Q000209:etiology; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000209:etiology / Q000503:physiopathology; D016030:Kidney Transplantation; D008133:Long QT Syndrome / Q000209:etiology / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis; D012307:Risk Factors; D014511:Uremia / Q000150:complications* / Q000503:physiopathology* / Q000628:therapy