Transcript Preoperative Evaluation and Management of Cardiac Patients

David W Kabel MD, FACC
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Shift of emphasis
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From preoperative risk stratification and testing
To perioperative management of risk
Prevention of major adverse cardiac events (MACE)
Challenge to previous guidelines
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Stress testing
Revascularization
Beta blocker therapy
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30 million+ non-cardiac surgeries in the US
annually
One third have known CAD or cardiac risk factors
500,000 considered high risk for cardiac
complications
Operative mortality is declining
Better preop risk stratification
 Better perioperative management
 Less invasive procedures
 Mortality is declining for high risk procedures as well
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Assessment of perioperative risk to guide
the decision to proceed with or the choice
of surgery
Determination of the need for changes in
management
Identification of cardiovascular conditions
that warrant long term management
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Shared decision making
Patient preferences and goals
PCP
Surgeon
Anesthesiologist
Specialists as needed
Requires considerable advanced planning in
high risk patients with multi-system disease
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Previously determined as low medium or high
risk
Now only 2 categories
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Low risk-<1%
 Cataracts
 Dermatologic and minor cosmetic
 Require no preop evaluation
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High risk-1% or greater
 Further workup depends on type of operation and
patient characteristics
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One point for each risk factor
Known ischemic heart disease
Heart failure (current or past history)
History of CVA or TIA
Insulin dependent diabetes
Creatinine> 2.0
High risk surgery-”Suprainguinal vascular,
intraperitoneal, or intrathoracic surgery”
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Points
Cardiac complications
%
0
0.4%
1
0.9%
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2
7%
10
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3+
11%
2
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Data from 525 hospitals and 1 million patients
to develop this
Considers type of surgery by CPT code
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Multiple patient factors are considered
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www.riskcalculator.facs.org
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These surgeries usually require no additional
preoperative cardiac evaluation
Breast
 Dental
 Endocrine
 Eye
 Gynecology
 Reconstructive
 Minor orthopedic(arthroscopy)
 Minor urologic(cystoscopy)
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Aortic surgery-(Open procedures)
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Major peripheral vascular
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Not high risk because of the nature of the
procedure
Almost all patients have multiple risk factors
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Known CAD
Previous revascularization
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Exertional symptoms
Previous cardiac evaluation
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Bypass
PCI-When and what was done?-Bare metal vs DES
When, and what did it show?
Exercise tolerance
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Most important predictor of perioperative outcome
Determines ability to increase O2 delivery
perioperatively
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Functional Capacity of 4 METS confers low risk
status
Can’t be evaluated in patients with mobility
problems
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Orthopedic procedures, especially joint replacement
COPD
PAD with claudication
 Very high risk population
 Known vascular disease
 AAA repair represents highest risk
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Signs of heart failure
Rales
 JVD
 Edema
 S3
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Tachycardia-Is patient in atrial fibrillation?
Bradycardia-Heart block, SSS
Murmur of aortic stenosis
Pulmonary findings-Wheezes
Any of these findings necessitate further workup
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Unstable coronary syndromes
Decompensated heart failure
Arrhythmias
Ventricular tachycardia
 AV block and sick sinus
 Uncontrolled atrial fibrillation or flutter
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Severe valvular disease
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Especially aortic stenosis
These patients need further evaluation prior to
noncardiac surgery
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Class III or IV symptoms
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Poor exercise tolerance
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Indications for stress testing or cath are same as
for those not undergoing noncardiac surgery
Patients with chronic stable angina (Class II) do
not require preoperative stress testing
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Greater perioperative risk than ischemia
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Should have EF measured
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BNP may have prognostic significance if normal
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Optimize therapy prior to surgery
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Beta blockers and possibly ACEIs and ARBs
should be continued perioperatively
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Severe aortic stenosis
AVA <1.0 cm2 or mean AV gradient >40 mm Hg, even in
absence of symptoms
 Should have AVR prior to noncardiac surgery, preferably
with a tissue prosthesis
 TAVR for high risk patients
 New guidelines suggest that asymptomatic patients with
severe AS may have surgery
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 Requires hemodynamic monitoring postop
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Severe mitral stenosis
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Can usually be treated with balloon valvuloplasty
Regurgitant lesions are well tolerated in the absence
of previous heart failure if LV function is normal
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Chronic atrial fibrillation and flutter
Control ventricular rate with beta blockers
 Determine if bridging with Lovenox is necessary
 Some procedures can be done without stopping
anticoagulants
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Newly diagnosed atrial fibrillation
Control ventricular rate, preferably with beta blockers
 Proceed with surgery
 Institute anticoagulation and specific anti-arrhythmic
therapy postoperatively
 Medical or electrical cardioversion postoperatively
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Mobitz I
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Mobitz II and 3rd degree block
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Review medications
No need for pacing if asymptomatic, proceed with
surgery
Review medications
If reversible causes not present, permanent pacemaker
indicated before surgery
Sick sinus syndrome
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Review medications
If asymptomatic, proceed with surgery
If symptomatic, permanent pacemaker indicated
May be useful to walk patient and observe HR response
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May lead to adverse outcomes
Appropriate in selected patients
High risk surgery
 Poor exercise tolerance
 Symptoms of possible ischemia
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 Exertional chest pain, tightness, heaviness
 DOE
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Routine stress imaging in asymptomatic patients is
poor at identifying patients who will have adverse
outcomes
Preoperative revascularization does not affect
outcomes
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BARI trial
No improvement in outcomes vs medical
treatment of angina preoperatively
Increased operative mortality if PCI within 12
days before surgery
Similar outcomes for PCI vs Bypass
Results duplicated in several trials
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No benefit in several studies
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CASS
CARP
CASS registry
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High risk vascular surgery patients randomized to
CABG vs medical treatment
Medical rx-2.4% mortality
CABG-0.9% mortality
BUT PREOP BYPASS HAD 1.4% MORTALITY,
MAKING MEDICAL AND CABG ARMS
EQUIVALENT
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Stress imaging is poor in identifying patients with
adverse outcomes
Angiography not always good at detecting disease
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Less occlusive plaque is often the most unstable
In autopsy studies, the infarct vessel was often not
the most stenotic on previous cath
Surgery and anesthesia can cause plaque
disruption and hyper-coaguable states
In nonsurgical populations revascularization has
no benefit over medical treatment in stable
patients
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Delayed surgery
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Anticoagulation and antiplatelet issues
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Morbidity and mortality inherent in the
revascularization procedure
Cost effectiveness
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I-Conditions for which there is evidence for
and/or general agreement that the procedure or
treatment is beneficial, useful, and effective
IIa- Weight of evidence is in favor of usefulness or
efficacy
IIb-Usefulness or efficacy is less well established
by evidence or opinion
III-Evidence or general agreement that the
procedure or treatment is not useful or effective
and in some cases may be harmful
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Beta blockers
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Statins
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ACEIs, ARBs
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Aspirin
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ADP receptor antagonists(antiplatelet drugs)
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Continue beta blocker therapy in patients
receiving Rx for angina, arrhythmias,
hypertension or other Class I indications
Level of evidence-B
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Management of beta blockers postop should be
guided by clinical circumstances, independent of
when the drug was started
May require temporary discontinuation due to
hypotension, bradycardia, or other conditions
LOE-B
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Patients with intermediate- or high-risk
myocardial ischemia noted in preoperative risk
stratification testing (LOE C)
Patients with 3+ RCRI risk factors (LOE B)
Patients with compelling long-term indications
for beta blocker therapy but no other RCRI risk
factors (LOE B)
Initiate beta blocker therapy long enough in
advance to assess safety and tolerability (LOE B)
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Patients with absolute contraindications to beta
blocker therapy
Risks outweigh benefits
Do not start on the day before or the day of
surgery (LOE B)
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Little evidence to support >30 day timeline
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Can be started 2-7 days before
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Optimal dosing and timing not defined
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Elevated perioperative stroke risk
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However, incidence of MACE much higher than
stoke.
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Initiate 2-7 or up to 30 days prior to surgery
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Titrate to resting pulse rate of 60-80
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Titrate to blood pressure of 130/80 or less
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Avoid hypotension
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Cardioprotective effects in perioperative period
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Improves endothelial morphology and function
Plaque stabilization
Discontinuation of chronic therapy
preoperatively is associated with adverse
outcomes
May benefit even started the day before surgery
Start therapy in high risk patients 7-30 days
before procedure-Class I, level B
Do not discontinue statin therapy
preoperatively-Class I, level C
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LV dysfunction
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Continue for high risk surgery-Class I, level C
Consider continuing for low risk surgery-Class IIa,
level C
Hypertension-Consider transient
discontinuation to avoid hypotension-Class IIb,
level C
Recommendations based on low level of
evidence
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Aspirin for secondary prevention usually should
not be discontinued in patients with previous
stents
15 % of recurrent ACS in stable CAD patients due
to discontinuing aspirin
Increased risk of stroke
Should only stop if expected bleeding risks and
sequelae are greater than known risk of stopping
Intracranial or back surgery
 Posterior eye chamber
 Prostate
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Most often arises after PCI
Premature discontinuation increases perioperative
M&M without reducing risk of bleeding
Elective surgeries should be postponed
PTCA-2-6 weeks
 Bare metal stent-30 days-The longer the better
 Drug eluting stents-12 months
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Emergency surgeries should be done on aspirin at least
and preferably on dual antiplatelet therapy
Exceptions are intracranial, intraspinal, and retinal
surgery
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Defined on basis of EKG changes and troponin
elevations
65% of MIs were asymptomatic
11% died within 30 days (58% of those within 48h)
Troponin elevation >3x normal was independent
risk factor in absence of symptoms or EKG
findings
Conclusion-At risk patients should be monitored
for perioperative infarction with EKGs and
enzymes for first three days postop
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Class I
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Class IIb
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Troponin level recommended if signs or symptoms
of myocardial ischemia or MI (LOE A)
EKG recommended if Sx or signs of ischemia or
MI(LOE B)
Usefulness of troponin or EKG in high risk patients
is uncertain without sx of signs of ischemia (LOE B)
Class III
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Routine screening with EKG or troponin in
unselected patients without Sx or signs is not useful
for guiding postoperative care
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1-Determine if the patient has had prior
revascularization-When and what?
2-Has patient had a cardiac workup in the last
several years?-What were the results?
3-Assess the patient’s functional capacity
4-Determine preoperative risk (RCRI or ACS risk
calculator)
5-Determine the pretest probability of cardiac
complications based on type of surgery and
institutional experience
6-Assess whether stress testing will alter pretest
probability of risk. Most of the time it will not.
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7-For elective surgery, determine if benefits
outweigh perioperative risk.
8-Determine if there are opportunities to
reduce cardiac complications by modifying
preoperative or intraoperative care
9-Develop strategies to minimize perioperative
risk, especially beta blockers and statins
10-Utilize careful postoperative monitoring to
identify nonfatal cardiac events and modifiable
risk factors to tailor long term therapy and
follow up
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Tell the patient
Find out how badly the patient wants the surgery
 Emphasize that the risks may outweigh the benefits
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Call the surgeon
How urgent is the operation?
 Is there a less invasive alternative?
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 Endovascular or laproscopic procedures
Is the surgeon willing to operate with patient on
antiplatelet drugs?
 Don’t back down if you really think the risk is too high.
Most surgeons do worry about operative mortality.
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Determine if there are risk factors that can be
modified to reduce risk and allow surgery at a
later date
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Uncompensated heart failure
Uncontrolled diabetes
Uncontrolled hypertension
Arrhythmias
COPD
Get a consult
There is no reason to do an elective operation
under less than optimal conditions
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Often no opportunity for preoperative
assessment or risk reduction
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Try to do risk stratification before OR
Postoperative monitoring for cardiac events
becomes more important in this setting
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The most important clinical indicator of
perioperative cardiovascular outcome is:
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A-Previous revascularization
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B-History of heart failure
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C-Functional capacity
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D-The type of surgical procedure
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A 74 y/o man is referred prior to THR. He has a
history of previous bypass 10 years ago. He is
asymptomatic but severely limited by his arthritis.
As part of his preop evaluation he should have:
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A-A treadmill GXT
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B-Cardiac catheterization
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C-Pharmacologic stress imaging
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D-EKG
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The man in the previous question is on aspirin,
lisinopril, and metformin. Prior to surgery his
regimen should be changed as follows:
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A-Add a long acting beta blocker
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B-Stop aspirin
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C-Add a statin
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D-Make no changes
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A 68 y/o woman comes in for preop evaluation
for colon resection for carcinoma. She has no
symptoms. Her pulse is 110 and irregular, BP
120/74, and an EKG shows atrial fibrillation.
She takes losartan and HCTZ. You should:
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A-Clear for surgery
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B-Start anticoagulation and postpone surgery until
after cardioversion
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C-Start beta blocker therapy and postpone surgery
until resting pulse rate <80