CARDIOVASCULAR MANAGEMENT UPDATE
From Anesthesiology Update 2007, sponsored by the Department of Anesthesiology, University of California, San
Diego, School of Medicine
| THE PRESENT AND FUTURE OF PERIOPERATIVE CARDIOVASCULAR MANAGEMENT —Joel A. Kaplan, MD,
Clinical Professor of Anesthesiology, University of California, San Diego, School of Medicine, Veterans Affairs San Diego
Medical Center, La Jolla, CA
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| Key points: heart failure (HF) reaching epidemic proportions because of cardiologists’ expertise in caring for patients with
coronary artery disease (CAD), ischemic heart disease, and other forms of cardiomyopathy; signs, symptoms, and treatment
of cardiac dysfunction related to neurohormonal responses; current treatment aims to prolong survival; low cardiac
output syndrome (LOS) different from chronic HF
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| Chronic HF: 5 million cases per year in United States; 0.5 million added per year; 250,000 deaths per year
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| Current and future treatment modalities for HF
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 | Current: cardiorenal—diuretics effective early in treatment; lead to production of neurohormonal elements; stimulate
angiotensin system; ultimately lead to further circulatory problems and advanced HF; cardiocirculatory—inotropic
agents; vasodilators; neurohormonal—angiotensin-converting enzyme (ACE) inhibitor; β-blocker
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| Future: antiremodeling therapy—surgeon redesigns heart; mechanical assist devices; new forms of cardiac resynchronization,
pacing, and defibrillation; gene therapy; stem cells
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| Classification of HF (from American College of Cardiology [ACC] and American Heart Association [AHA])
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| Stage A: high risk for HF; examples—CAD; hypertension; diabetes; treatment—prevention (exercise; diet); maintain
blood pressure (BP) and lipids in normal range; consider ACE inhibitor (used for hypertension)
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| Stage B: more advanced; structural heart disease associated with HF; relatively asymptomatic; examples—left ventricular
(LV) hypertrophy; valvular heart disease; previous myocardial infarction (MI); treatment—ACE inhibitor or β-blocker
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| Stage C: structural heart disease with current or previous symptoms of HF; managed pharmacologically; examples—
dyspnea or other symptom of HF; diastolic or systolic dysfunction; treatment—does not respond to inotropic drugs
(given only in acute situations)
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| Stage D: symptomatic with or without treatment; decompensating state of HF; 1 to 3 yr survival; examples—
hospitalized frequently (high mortality in hospital); at home on intravenous (IV) medications or assist device;
treatment—most any intervention that might reverse and move to stable situation
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| Renin-angiotensin system: intervention based on conversion areas; renin conversion to angiotensin I blocked with β-
blockers; ACE inhibitors standard drugs; angiotensin receptor blockers (ARBs) given when ACE inhibitors cannot be
tolerated (combined with ACE inhibitor in some cases); aldosterone antagonists effective in reducing symptoms of HF
and in interfering with hormonal regulation; ACE inhibitors and ARBs may cause hypotension (debate about discontinuing
day before surgery); new drug therapy (eg, vasopressin) used to reverse vasodilatation
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| beta-blockers in HF: carvedilol (Coreg)—affects β1 and β2 adrenoreceptors; also α-adrenergic blocker; similar to labetalol;
widely used; improves systolic function and myocardial energy utilization; reduces morbidity and mortality
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| Natriuretic peptides: brain natriuretic peptide (BNP)—diagnostic tool; secreted in cardiac ventricles; biomarker for congestive
HF; recombinant BNP—pharmacologic product; vasodilator; nesiritide (Natrecor) reduces symptoms of HF; hemodynamics
similar to nitroglycerin; fewer arrhythmias than with inotropic agents; fewer electrolyte problems; most
studies seem to indicate patients “getting worse”
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| LOS: pathophysiology involves inadequate O2 supply to heart and acute ischemia from ongoing disease or mechanical
intervention; causes tachycardia, arrhythmias, and LOS; mortality may result if treated incorrectly
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| Risk factors after cardiopulmonary bypass (CPB): preoperative LV dysfunction; myocardial ischemia; poor myocardial
preservation; complications from cardioplegia; inadequate surgical repair; valvular heart disease
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| Management: requires logical series of steps; heart rate (HR) and rhythm (normal sinus rhythm, pacing); preload (Starling
curve); afterload (impedance reduction); contractility (inotropic agents, vasodilators, “pharmacologic [intraaortic]
balloon pump” [IABP]); O2 delivery (O2 , hemoglobin); pulmonary artery catheter and transesophageal echocardiography
valuable in select patients
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| Pharmacologic approaches to LV dysfunction: metabolic supplements (eg, insulin)—may be important to aid glucose
and improve myocardial function; catecholamines—include dobutamine, dopamine, and epinephrine (speaker’s first
choice); all increase myocardial O2 demand; effective for short period of time in moderate dose; phosphodiesterase
inhibitors—milrinone (key drug; noncatecholamine; nonadrenergic; increases cyclic adenosine monophosphate [AMP];
50 µg/kg loading dose and 0.5 µg/kg per minute infusion); combination inotropic drug and phosphodiesterase inhibitor
better than either alone; preemptive phosphodiesterase inhibitor use—avoid “failed wean” from CPB; minimal side effects
on CPB (50 µg/kg loading dose); follow with inotropic drug (gain benefits of vasodilator while maintaining coronary
perfusion pressure); if possible, avoid mechanical assist devices
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| Levosimendan: approved in Europe and used widely; new inodilator; works primarily in cell, on calcium mechanism; facilitates
calcium in myofilaments; no increase in myocardial O2 demand; no arrhythmias; improves contractility; not
found to be more effective than milrinone or dobutamine (but not looked at for short-term use in perioperative period)
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| Uses for IABP and counterpulsation devices: failure to wean from CPB; support during percutaneous intervention in
catheterization laboratory; emergency preoperative support; bridge to further therapeutic intervention
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| Surgical options for HF: further revascularization or valve replacement or repair; cardiac resynchronization combined
with implantable cardiac defibrillator (becoming “major intervention” for HF [particularly with LV dysfunction]); LV reconstruction;
mechanical assist devices
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| Ventricular assist devices: implantable LV assist device; bridge to recovery; destination therapy; enormous cost
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| Genomics and HF: rule out family diseases in certain types of cardiomyopathy; pharmacogenomics for better selecting
drugs, determining why metabolized differently, and dosing; in end-of-life care stage, to select better drugs and new interventions;
new agents may be given to replace or regenerate receptors and affect balance in heart between apoptosis and
hypertrophy; leads to proper regeneration of cardiac tissue
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| PERIOPERATIVE CARDIAC RISK AND NONCARDIAC SURGER Y—David M. Roth, MD, PhD, Associate Professor
of Anesthesiology, University of California, San Diego, School of Medicine, Veterans Affairs San Diego Medical Center,
La Jolla, CA
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| Introduction: 100 million noncardiac surgeries worldwide each year; ≈30 million in United States; 1.5 million patients suffer
perioperative cardiovascular morbidity (eg, cardiac death, MI, heart failure, significant arrhythmia); cost ≈$20 billion
in 1995; ACC and AHA first published guidelines on perioperative cardiovascular evaluation for noncardiac surgery in
1996, updated in 2002; guidelines not derived from prospective studies; uncertainty about predictive accuracy; never
compared to other validated cardiovascular risk indices (eg, Revised Cardiac Risk Index [RCRI]); new updates available
in 2007
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| Cardiovascular risk indices: Goldman (1977) looked at indices of cardiac risk in noncardiac surgery; developed 9 independent
risk factors for life-threatening or fatal cardiac complications; RCRI for noncardiac surgery identified 6 factors,
1) high-risk surgery (thoracic, abdominal, or pelvic vascular procedure), 2) ischemic heart disease (defined as history of
MI, current angina, use of sublingual nitroglycerin, positive exercise test, Q waves on electrocardiography [ECG], history
of percutaneous transluminal coronary angioplasty [PTCA] or coronary artery bypass grafting [CABG] with chest pain
presumed of ischemic origin), 3) heart failure (LV failure based on physical examination, paroxysmal nocturnal dyspnea,
pulmonary edema, S3 or bilateral rales on physical examination, and pulmonary edema on chest x-ray), 4) cerebrovascular
disease (transient ischemic attack, cerebrovascular accident), 5) insulin-dependent diabetes, and 6) chronic renal insufficiency;
greater number of risk factors correlates with increased risk for major perioperative cardiac event; eg, no risk
factors predicts 0.4% risk for major perioperative cardiac event, ≥3 risk factors predicts risk of 5.4%; RCRI provides accurate
estimate of perioperative risk that can be used to direct subsequent patient care
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| Preoperative cardiovascular testing: 2002 ACC/AHA guidelines recommended further preoperative testing if 2 of 3 factors
present (intermediate clinical predictors, poor functional capacity, or high surgical risk); however, no need for test if
result will not alter patient management; shift from test-and-fix to medical management; medical treatments now obviate
testing strategies in most cases; study (Poldermans) found patients who did not have tests had similar risk (actually lower)
as patients who were tested (≈1.8% vs 2.3%); conclusion that cardiac testing can be omitted in intermediate-risk patients if
β-blockers and tight HR control used; another study showed better predictive value with stress echocardiography than with
perfusion imaging; moderate-to-large defect detected by either technique resulted in 9-fold increase in risk; results support
performing quantitative ischemic assessment before noncardiac surgery in almost all patients at moderate or high risk;
whether testing improves outcomes remains unproven; dobutamine echocardiography may be superior test, but choice of
tests should be based on need to assess valve or ventricular function and local reliability and availability of tests; recommend
pharmacologic stress testing in patients with 1 or 2 RCRI criteria and limited functional status
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| Coronary angiography and coronary artery revascularization: ACC/AHA guidelines recommend that any patient with
unstable cardiovascular disease or at high risk after noninvasive testing be considered for angiography, medical management,
and possible angioplasty or CABG; criteria for angioplasty and CABG should be identical whether patient
scheduled for noncardiac surgery or not having surgery; study (McFalls) of coronary artery revascularization and prophylaxis
found no difference in mortality between groups within 2.7 yr of follow-up; no significant difference between
groups in MI rate within 30 days of surgery (12% in revascularized group, 14% in non-surgery group); study underpowered
to assess in-hospital cardiac events; concluded that coronary artery revascularization before elective vascular
surgery does not alter long-term outcome; some suggest results support shift from testing to medical optimization in
noncardiac surgery; others cite possible benefit from revascularization in subgroup with significant perfusion defects;
patient with RCRI >3 and at high risk by testing should be considered for catheterization; evidence supports revascularization
only if required in absence of surgery or if patient had left main CAD, multivessel CAD, low ejection fraction
(EF), or aortic stenosis; CABG vs percutaneous intervention
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| Timing: 2002 guidelines suggest delaying noncardiac surgery at least 2 wk, and, ideally, 4 to 6 wk, if stent placed during
angioplasty, to allow completion of antiplatelet therapy and endothelialization of stent; use of drug-eluting stents complicates
issue; delaying endothelialization of stent requires prolonged periods of antiplatelet therapy; sirolimus stents
require 3 mo of dual antiplatelet therapy with clopidogrel (Plavix) and aspirin, and paclitaxel stents require 6 mo of
dual antiplatelet therapy; some suggest delaying noncardiac surgery for 3 mo after sirolimus stents and 6 mo after paclitaxel
stents; McFadden reported 3 cases of late stent thrombosis >11 mo after drug eluting stent placement; separate
study concludes all patients with drug eluting stents should continue clopidogrel for ≥12 mo
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| Perioperative medical therapy: 2002 guidelines suggest appropriately administered β-blockers reduce perioperative ischemia
and may reduce risk for MI and death in high-risk patients; recommendation based on 2 randomized trials; β-
blockade encouraging, but evidence warrants cautious interpretation; ACC/AHA recently published focused update on
perioperative β-blocker therapy (2006)
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| Recommendations: Class I—administer β-blockers for vascular surgery (with CAD or high cardiac risk) and for myocardial
ischemia on preoperative testing (level B evidence); also use for patients undergoing surgery and already on β-blockade
(level C evidence); Class IIa—reasonable to administer β-blockers for vascular surgery with CAD or high cardiac
risk, or for high- or intermediate-risk surgery with CAD or high cardiac risk; Class IIb—consider β-blockade
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| Statins: 3-hydroxy-3-methylglutaryl (HMG) CoA reductase inhibitors; decrease cholesterol synthesis; increase endothelial
nitric oxide; anti-inflammatory; stabilize plaques; decrease platelet aggregation; greatly reduce risk for further cardiac
events; small trial showed significant reduction in cardiac events within 6 mo of surgery in atorvastatin vs placebo
group; Auerbach and Goldman recommendation that statins be started before noncardiac surgery whenever long-term
lipid-lowering therapy indicated; also contentious issue; ACC/AHA guidelines currently recommend stopping statin
use in noncardiac surgery because of risk of rhabdomyolysis and other low-incident events
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| α2 -adrenergic agonists (eg, clonidine): may decrease cardiac event rates in noncardiac surgery; Wallace showed clonidine
decreased incidence of perioperative MI and postoperative mortality over 2 yr in noncardiac surgery; Goldman review
states that until large-scale trial, consider α2 -agonists as prophylaxis in high-risk patients intolerant of β-blockers
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| Anesthetic techniques: in 2002, no one technique considered best for myocardium protection; original guidelines stressed perioperative
pain management as crucial aspect of care in cardiac patients; summary by Goldman states neuraxial anesthesia,
especially when continued postoperatively, consistently better than, or at least as good as, general anesthesia (although evidence
limitations make broad recommendations difficult)
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| Postoperative management: remain vigilant for myocardial ischemia; most ischemic events occur postoperatively; initiate
cardiac risk reduction measures in patients in whom CAD detected during preoperative evaluation
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Suggested Reading
Auerbach A, Goldman L: Assessing and reducing the cardiac risk of noncardiac surgery. Circulation 113:1361, 2006;
Donahue MP et al: Redefining heart failure: the utility of genomics. J Am Coll Cardiol 48:1289, 2006; Durazzo AE et al:
Reduction in cardiovascular events after vascular surgery with atorvastatin: a randomized trial. J Vasc Surg 39:967, 2004;
Fleisher LA et al: ACC/AHA 2006 guideline update on perioperative cardiovascular evaluation for noncardiac surgery: focused
update on perioperative beta-blocker therapy: a report of the American College of Cardiology/American Heart Association
Task Force on Practice Guidelines. Circulation 113:2662, 2006; Fleisher LA: Perioperative beta-blockade: how
best to translate evidence into practice. Anesth Analg 104:1, 2007; Hauptman PJ et al: Use of nesiritide before and after
publications suggesting drug-related risks in patients with acute decompensated heart failure. JAMA 296:1877, 2006; Kaplan
JA: Amrinone: contemporary management of the low cardiac output syndrome. Introduction. J Cardiothorac Anes
3:1, 1989; Kaplan JA: The role of nicardipine during anesthesia and surgery. Clin Ther 11:84, 1989; Kersten JR et al: Statins:
The next advance in cardioprotection? Anesthesiology 105:1079, 2006; London MJ: Con: Beta-blockers are indicated
for all adults at increased risk undergoing noncardiac surgery. Anesth Analg 104:11, 2007; Mangano DT et al: Effect
of atenolol on mortality and cardiovascular morbidity after noncardiac surgery. Multicenter Study of Perioperative Ischemia
Research Group. N Engl J Med 335:1713, 1996; Erratum in: N Engl J Med 336:1039, 1997; McFalls EO et al:
Coronary-artery revascularization before elective major vascular surgery. N Engl J Med 351:2795, 2004; Poldermans D et
al: Beta-blocker therapy in noncardiac surgery. N Engl J Med 353:412, 2005; Poldermans D et al: Statins are associated
with a reduced incidence of perioperative mortality in patients undergoing major noncardiac vascular surgery. Circulation
107:1848, 2003; Schouten O et al: Pro: Beta-blockers are indicated for patients at risk for cardiac complications undergoing
noncardiac surgery. Anesth Analg 104:8, 2007; Wallace A et al: Use of beta-blockade to prevent death after noncardiac
surgery. West J Med 166:203, 1997.
Educational Objectives
| The goals of this program are to improve the management of heart failure (HF) and the management of perioperative cardiovascular
risk during noncardiac surgery. After hearing and assimilating this program, the participant will be better able
to:
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| 1. Discuss current and future treatment modalities for HF.
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| 2. Review the American College of Cardiology/Amer-ican Heart Association 4-stage classification of HF.
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| 3. Describe the pathophysiology and management of acute HF.
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| 4. Outline cardiovascular risk indices and preoperative cardiovascular testing for perioperative cardiovascular risk in
noncardiac surgery.
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| 5. Recommend medical therapy for perioperative cardiovascular risk in noncardiac surgery.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty members to disclose relevant
financial relationships within the past 12 months that might create any personal conflicts of interest. Any identified
conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary business
or commercial interest. For this program, the faculty reported nothing to disclose.
Acknowledgements
Drs. Kaplan and Roth spoke at Anesthesiology Update 2007, held January 3-6, 2007, in San Diego, CA, and sponsored by
the University of California, San Diego, School of Medicine, Department of Anesthesiology. The Audio-Digest Foundation
thanks the speakers and the sponsor for their cooperation in the production of this program.
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