Perioperative Management of the Patient with Coronary Artery Disease

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Perioperative Management of the Patient with
Coronary Artery Disease

• IARS 2006 Review Course Lecture
• James G. Ramsay, MD
• 
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• 2006.04.04

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• ACC/AHA Task Force Report Special Report
  Guidelines for perioperative cardiovascular
  evaluation for noncardiac surgery.
• (Circulation 1996 931278-1317)
• ACC/AHA Guideline Update for Perioperative
  Cardiovascular Evaluation for Noncardiac Surgery
  - Executive Summary a report of the ACC/AHA task
  force on practice guidelines
• (J Am Coll Cardiol 2002 39542-553)
• Clinical predictors Functional capacity
• Surgery-specific risk

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Preoperative Management
--revascularization --beta-blockade
--alfa-2 agonist --statin
--sulfonylurea
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• No benefit from CABG before aortic or lower
  extremity vascular surgery in pt with moderate
  coronary disease.
• (Coronary revascularization before major
  elective surgery. NEJM 2004 3512795-2804)
• The risks of coronary surgery add morbidity and
  cost to that of the planned surgery.
• (The role of coronary angiography and
  revascularization before noncardiac vascular
  surgery JAMA 1995 2731919-1925)

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• Angioplasty/stent placement may result in acute
  mortality if surgery follows in less than a
  month.
• (Catastrophic outcomes of noncardiac surgery
  soon after coronary stenting. J Am Coll Cardiol
  2000 351288-1294)

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• Reduction in adverse cardiac outcomes with the
  use of periop beta-blockade for vascular surgery
• (Effect of atenolol on mortality and
  cardiovascular morbidity after noncardiac
  surgery. NEJM 1996 3351713-1720)
• (Prophylactic atenolol reduces postop
  myocardial ischemia. Anesthesiology 1998
  887-17)
• (The effect of bisoprolol on periop mortality
  and myocardial infarction in high-risk patients
  undergoing vascular surgery. NEJM 1999
  3411789-1794)

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• Beta-blockade slightly reduced ischemic events in
  pt lt 3 risk factors for CAD and dobutamine
  stress echocardiography (DSE) was of minimal
  value In pt with 3 or more risk factors without
  wall motion abnormality on DSE, beta-blockade
  reduced events significantlyin those with modest
  wall motion abnormality, beta-blockade was
  associated with a dramatic reduction in events.
• (Predictors of cardiac events after major
  vascular surgery role of clinical
  characteristics, dobutamine echocardiography, and
  beta-blocker therapy. JAMA 2001 2851865-1873)

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• Stress-related periop myocardial infarction.
• (Myocardial infarction after vascular
  surgery the role of prolonged, stress-induced,
  ST depression-type ischemia. J Am Coll Cardiol
  2001 311839-1845)
• Catheterization before and after surgery many
  infarctions occurred in areas distal to a preop
  occlusion, supplied by collaterals, and others
  occurred without any occlusion being observed.
• (Angiographic correlates of cardiac death and
  myocardial infarction complicating major
  nonthoracic vascular surgery. Am J Cardiol 1996
  771126-1128)

The relative lack of benefit from
revascularization procedures in moderate coronary
disease and the benefit from beta-blockade in
these same patients
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• Alfa-2 agonists may reduce the incidence of
  myocardial ischemia.
• (Effect of mivazerol on periop cardiac
  complications during non-cardiac surgery in
  patients with coronary heart disease the
  European mivazerol tiral(EMIT). Anesthesiology
  1999 91951-961)
• (Small,oral dose of clonidine reduces the
  incidence of intraop myocardial ischemia in
  patients having vascular surgery. Anesthesiology
  1996 85706-712)
• Patients receiving statin at the time of surgery
  may have a decreased mortality.
• (Statins are associated with a reduced
  incidence of periop mortality in patients
  undergoing major noncardiac vascular surgery.
  Circulation 2003 107 1848-1851)

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• Sulfonylurea hypoglycemic drugs may interfere
  with myocardial preconditioning mechanisms.
• (Preop shift from glibenclamide to insulin is
  cardioprotective in diabetic patients undergoing
  CABG. J Cardiovasc Surg(Torino) 2004 45 117-122)

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Intraoperative Monitoring --EKG
--Pulmonary Artery Catheter(PAC)
--Transesophageal echocardiography (TEE)
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• V5 lead of the EKG is the single most sensitive
  lead for detecting periop ischemia, with 75 the
  sensitivity of all 12 leads. (Intraoperative
  myocardial ischemia localization by 12-lead EKG.
  Anesthesiology 1988 69232-241)
• V4 is the most sensitive.
• (Periop myocardial ischemia and infarction.
  Anesthesiology 2002 96259-261)
• Both studies indicate 2 or 3 precordial leads
  will detect more than 90 ischemia from all 12
  leads.

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• PAC or TEE monitoring contraversial.
• Comparative studies have failed to demonstrate
  that either technique provides a benefit over 2-
  lead EKG monitoring.
• (Comparison of hemodynamic,
  electrocardiographic, mechanical, and metabolic
  indicators of intraoperative myocardial ischemia
  in vascular surgical patients with CAD.
  Anesthesiology 1989 7019-25)
• (Monitoring for myocardial ischemia during
  noncardiac surgery a technology assessment of
  TEE and 12-lead EKG. JAMA 1992 268210-216)

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• Two randomized trials in abdominal aortic
  surgical patients failed to demonstrate a benefit
  with the use of PACs.
• (The value of pulmonary artery and central
  venous monitoring in patients undergoing
  abdominal aortic reconstructive surgery a
  comparative study of two selected, randomized
  groups. J Vas Surg 1990 12754-760)
• (Canadian Critical Care Clinical Trials
  Group. A randomized controlled trial of the use
  of pulmonary-artery catheters in high-risk
  surgical patients. NEJM 2003 3485-14)

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• Guidelines for the periop use of PAC and TEE do
  not recommend use of these technologies for
  routine monitoring in patients with CAD.
• They should be considered when there is a
  diagnoctic or treatment question that can be
  answered or guided by the additional informaton
  or where there is a known Hx of cardiac
  dysfunction such as CHF in a pt undergoing major
  surgery.

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Anesthetic Technique --volatile
anesthetic --IV anesthetic --regional
anesthesia and analgesia
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• Principles maintain coronary perfusion pressure
  avoid increases in myocardial oxygen demand.
• Volatile anesthetics may have cardio-protective
  properties.
• (Anesthetic preconditioning serendipity and
  science. Anesthesiology 2002 971-3)
• In patients undergoing CABG, volatile anesthetic
  based protocol were associated with less
  myocardial enzyme release than IV drug based
  protocol.
• (Choice of primary anesthetic regimen can
  influence ICU length of stay after coronary
  surgery with CPB. Anesthesiology 2004 1019-20)

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• Meta-analysis of 141 trials significant
  reduction in mortality and complications with
  spinal/epidural anesthesia.
• (Reduction of postoperative mortality and
  mobidity with epidural or spinal anesthesia
  results from overview of randomized trials. BMJ
  2000 3211493-1497)
• A large randomized trial of periop epidual
  blockade in major surgery failed to confirm these
  findings but these was a clear benefit in terms
  of pain control and an apparent reduction of resp
  failure.
• (Epidural anesthesia and analgesia and outcomes
  of major surgery a randomized trial. Lancet
  2002 3591276-1282)

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• More than 50 of intraop EKG-detected ischemic
  episodes do not appear to be related to
  hemodynamic change there is an association
  between tachycardia and ischemia both
  intraoperatively and postoperatively.
• (Does perioperative myocardial ischemia lead
  to postoperative myocardial infarction?
  Anesthesiology 1985 62107-115)
• (Perioperative myocardial ischemia in
  patients undergoing noncardiac surgery. II
  incidence and severity during the first week
  after surgery. The Study of Perioperative
  Ischemia Research Group. J Am Coll Cardiol 1991
  17 851-857)

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• Most, if not all, significant myocardial enzyme
  release after vascular surgery was preceded by
  prolonged period of ST segment depression,
  usually associated with tachycardia.
• (Myocardial infarction after vascular
  surgery the role of prolonged, stress-induced,
  ST depression-type ischemia. J Am Coll Cardiol
  2001 311839-1845)
• Avoidance of major changes in CPP and heart rate
  should be a priority in these patients.

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• Preoperative anemia and perioperative hypothermia
  have been associated with adverse cardiac
  outcomes.
• (Perioperative myocardial ischemic episodes
  are related to hematocrit level in patients
  undergoing radical protatectomy. Transfusion
  1998 38 924-931)
• (Perioperative maintenance of normothermia
  reduces the incidence of morbid cardiac events a
  randomized clinical trial. JAMA 1997
  2771127-1134)

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Postoperative Management
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• The risk of perioperative myocardial infarction
  continues into the first postoperative week
  continuation of beta-blockade into this period is
  probably essential for the protective effects
  documented above.
• Continuation of EKG or other monitoring into the
  postoperative period has not been evaluated in a
  prospective trial.

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• Even relatively low levels of troponin I release
  after major vascular surgery are associated with
  adverse cardiac outcomes.
• (Early and delayed myocardial infarction
  after abdominal aortic surgery. Anesthesiology
  2005 102885-891)
• It may be that routine sampling for this enzyme
  in these high-risk patients (major vascular
  surgery) would afford an early opportunity to
  intervene.

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• Many ischemic episodes are associated with
  tachycardia, which may be related to the
  sympathetic stimulation which occurs with pain.
• Beta-blokade cannot substitute for adequate
  analgesic techniques.

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Thanks for your attention