Transcript Cardiovascular Disaster in Hemodialysis patients

Cardiovascular Disaster in
Hemodialysis patients
Pattaraporn MD.
Causes of death in prevalent
dialysis patients 2008-2010
41.6%
26.5%
Cardiovascular Disaster
Sudden death
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Unexpected natural death
Within a short time period >> 1-24 h
Due to cardiac etiology
New or more serious symptoms
Possible Mechanisms Responsible for SD
in HD
Rapid electrolyte
shifts/Hypervolemia
QT dispersion
Cardiac arrhythmia
Cardiac arrest
Inflammation
cardiomyopathy
•Myocardial
interstitial
fibrosis
•Microvessel
disease
•CHF
•CAD/MI
•LVH/LV
dysfunction
Ischecmic heart disease
Sympathetic overactivity
Left ventricular Hypertrophy and Heart
failure
Concentric LV hypertrophy
Eccentric LV hypertrophy
Left ventricular Hypertrophy and Heart
failure
• LVH is an powerful indicator of mortality in
dialysis patients
• Presence of LVH >>> arrhythmia
• Left ventricular systolic dysfunction >>
arrhythmia
Redaelli B: Lancet 1988;ii:305–309.
Myocardial Interstitial fibrosis and Microvessel
disease
Inadequate capillary density + increased oxygen
demand >> relative hypoxia >> fibrosis
Myocardial Interstitial fibrosis and Microvessel
disease
• Fibrous tissue >> high electrical resistance
• Development of atrial and ventricular reentry
types of arrhythmias
• Risk factor for the development of
arrhythmias especially during the dialysis
QT Dispersion
• Difference between the longest and shortest QT
intervals >> EKG 12 lead
• Predict an increased risk of malignant
arrhythmias
• Normal value of QT dispersion in normal subjects
was ≤40 ms
• Dialysis patients with QT dispersion > 74 ms >> 
ventricular arrhythmias or SD
• Low K+ and low Ca2+ >> acquired long QT
syndrome
Sympathetic overactivity
•  Heart rate >> myocardial demand  supply
>> cardiac hypertrophy and fibrosis
• Decrease heart rate variability (reflecting
autonomic dysfunction) >> increased risk for
all-cause and SD in HD
Inflammation
• Marker : C-reactive protein, inhibit the hepatic
generation of albumin
• Reflection of vascular injury VS actually promotes
vascular injury ?
• High CRP level ( >6 mg/l ) : independent ,
predictive marker of future myocardial infarction
– Herzig, K. A. et al. J. Am. Soc. Nephrol. 12, 814–821 (2001).
• Inflammation could trigger SD >> atherosclerosis
or direct effect on myocardium
Other factors
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Rapid electrolyte shifts
Hypervolemia
Anemia
Dyslipidemia
Hypertension
Calcium/phosphate deposition
Avoiding low K
dialysate & rapid
electrolyte shifts
ACEI and
ARBs
Prevention of
Sudden Death
Implantable
defibrillators
Beta-blocker
Beta-blocker
• Reduction of
– Cardiac hypertrophy & fibrosis
– Antifibrillary activity
– Ventricular arrhythmia
– Reduced risk of acute MI
• Improve Heart rate variability
• Increase in baroreflex sensitivity
ACEI and
ARBs
• Reduction of
– Cardiac hypertrophy & fibrosis
– Fatal arrhythmia
Avoiding low K dialysate & rapid
electrolyte shifts:
• To avoid
– QT dispersion
– Re‐entrant arrhythmias
– Premature ventricular extrasystole (VES)
Implantable defibrillators
or Implantable Cardioverter Defibrillators (ICDs)
• Most effective therapy for SCD in the general
population
• Indication
– Survival of cardiac arrest due to VT or VF
– Episode of sustained VT causing severe hemodynamic
compromise
– Episode of sustained VT without hemodynamic
compromise + EF 35%
– MI + EF 35% + nonsustained VT on 24-h ECG +
inducible VT on electrophysiologic testing
– MI + EF 30% QRS duration  120 ms on ECG
Implantable defibrillators
or Implantable Cardioverter Defibrillators (ICDs)
• 42% risk reduction for death in dialysis
patients with ICDs implanted according to
conventional guidelines
• Greater risk of device complications
• No statistically increase >>> infection or
fistula thrombosis
– Kidney Int. 2005;68:818-825.
Herzog CA et al. Kidney Int. 2005;68:818-825.
Thank You