Cardiac revascularization in dialysis patients: risks

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Cardiac revascularization in dialysis patients
risks benefits

• Theo Hattingh
• Tygerberg Hospital
• University of Stellenbosch

2

• 58 yr male
• ESRF due to diabetic nephropathy
• HD x 4 yrs
• Metabolic syndrome ?BMI, diabetes, hypertension
  ?cholesterol, gout
• Diabetic complications
• Retinopathy
• IHD PTCA
• No PVD

3

• Angina dyspnoea similar to before PTCA 3 yrs
  earlier
• Hb 11, BP well-controlled
• Cardiology consult
• Positive exercise ECG
• Angiogram Normal LV function
• LCx 50
• RCA 99 ? PCI unsuccessful
• CABG
• Technically difficult due to extensive
  calcification
• Postoperative hypotension
• Ischaemia of L leg fem-pop bypass
• Sepsis
• AV fistula thrombosed

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Acute myocardial infarction

• Overall 3 yr mortality post AMI
• in non-renal patients lt 75 yrs
• (reperfusion era)
• 20
• Herlitz, Am Heart J 2002

• Overall 2 yr mortality post AMI
• in dialysis patients
• (1990 1995)
• 74
• Reluctance to treat?
• Underutilization of thrombolysis
• Underutilization of beta-blockers
• Herzog, NEJM 1998

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Revascularization

• Improve survival
• Left main CAD
• 3-vessel disease (esp. if ?LV function)
• 2-vessel disease, including proximal LAD
• 1- or 2-vessel disease (not including LAD)
  large area viable myocardium high-risk criteria
  on noninvasive testing
• Control symptoms

ACC/AHA, Circulation 2004
6
PCI vs. CABG for multivessel diseaseNon-renal
patients
PCI PTCA ? stent
1 NEJM 1996 2 NEJM 2001 3 Lancet 2002
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BARI 10 - 12 yr follow-up

• CABG had 53 higher cost initially, but the gap
  closed to lt5 in the first 2 years
• CABG PTCA (for multi-vessel disease) costs
  equivalent at 10 yrs
• Quality of life better in the first 3 years after
  CABG thereafter equivalent to PTCA

Hlatky, Circulation 2004
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Revascularization in dialysis patients

• No prospective randomized trials
• Exclusion from major revascularization trials
• Incomplete retrospective data
• e.g. LV function, type of coronary lesion
• Decision algorithms PTCA vs. CABG

In the absence of clear guidance therapeutic
nihilism has flourished. Goldsmith, KI
2001
9
US Renal Data System

• Review of revascularization in 15 784 dialysis
  patients 1995 - 1998

plt0.0001
USRDS 2-yr dialysis survival 62 (1997)
Herzog, Circulation 2002 USRDS 1997
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PCI in dialysis patients

• PTCA has a high incidence of restenosis
• 40 80 (vs. 33 in non-diabetic non-uraemic
  patients)
• CABG provides better freedom from angina, MI,
  long-term survival than PTCA
• Stenting had better patency in small studies
• 30 35 restenosis at 2 yrs
• Other unresolved issues
• Drug eluting stents
• Effect of antiplatelet drugs
• Intracoronary radiation
• Laser revascularization

Tadros, JN 2004 Goldsmith, KI 2001
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Best, J Am Coll Cardiol 2002
12
CABG in dialysis patientsNorthern New England
Cardiovascular Disease Study Group1992 - 1997
USRDS 5-yr dialysis survival 30 (1997)
Liu, Circulation 2000 Dacey, Ann Thorac Surg
2002
13
CABG in diabeticsNorthern New England
Cardiovascular Disease Study Group1992 2001
11 186 diabetes patients
Leavitt, Circulation 2004
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CABG in dialysis patients

• USRDS re-analysis
• CABG survival benefit over PCI only in the group
  of patients where LIMA to LAD
• Equivalent to PCI when CABG performed without
  internal mammary grafts
• Ideal strategy?
• LAD lesion CABG with LIMA
• No LAD lesion Stent if anatomically suitable
• Off-pump CABG?

Herzog, J Am Soc Nephrol 2003
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CABG in dialysis patients

• More severe generalized atherosclerosis
  calcification
• Uraemic CAD resembles the pattern of diabetes
  old age
• Technical difficulty anastomosing vessels onto
  calcified coronary arteries
• Risk of calcific emboli during handling of the
  aorta
• Immune compromised

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Revascularization vs. Medical treatment

• Only one randomized study in 19921
• 151 asymptomatic diabetics awaiting
  transplantation
• Medical therapy (CCB aspirin) vs. PTCA/CABG
• ? cardiac events death in PTCA/CABG group
• Based on the available evidence, medical
  treatment alone is only justified if2
• The patient is not expected to live long enough
  to benefit PCI/CABG protection
• Procedure risk deemed unacceptable
• Is revascularization appropriate in dialysis
  patients medically unfit for transplantation?

1Manske, Lancet 1992 2Goldsmith, KI 2001
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Summary - Revascularization

• Data limited to observational studies
• Acceptable long-term outcome, but significantly
  worse than in the general population
• PTCA has very high restenosis rate
• Stents more promising
• CABG hospital mortality 10 15
• CABG superior to PCI beyond 6 months - preferred
  in multi-vessel disease, esp. if LAD lesion

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Issues for discussion
In the absence of clear guidance therapeutic
nihilism has flourished Goldsmith, KI 2001

• Are we also guilty?
• Is the available data locally applicable?
• What is current local practice?
• Should we pool our data?
• Time for SARS/SAHA guidelines?

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Pre-transplant revascularization

• Transplantation in patients with CAD
• ? graft loss
• ? peri-operative morbidity
• ? long-term mortality
• Screening
• Stress ECG limited by LVH exercise capacity
• Nuclear imaging stress Echo sens spec lower
  than non-renal patients
• Poor LV function ? must exclude ischaemia

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Pre-transplant assessment
History IHD ECG features of IHD Poor LV function
Age lt 50, and ECG no ischaemia No history
IHD Normal LV function
All others
Diabetes?
Thallium scintigraphy or Stress echo
or Doubt
Coronary angiography
No further investigations
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