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PREOPERATIVE EVALUATION in the
ELDERLY
Module 2
CARDIAC ASSESSMENT
Ed Vandenberg, MD, CMD
Geriatric Section OVAMC
&
Section of Geriatrics
981320 UNMC
Omaha, NE 68198-1320
[email protected]
Web: geriatrics.unmc.edu
OBJECTIVES:
Upon completion the Learner will be able to:
• List the key tasks in a preoperative cardiac
evaluation
• List cardiac the cardiac risk factors,
functional capacity assessment and surgical
procedure risk for a preoperative evaluation.
• Describe pre-op evaluation cardiac
evaluation.
EXPLANATION of PROCESS
Step one: You will leave this PowerPoint and enter the module at the web-based
address below. After module is entered, review the summary card on the left hand
side of page. It will enlarge by clicking on it.
Step two: after familiarizing yourself with the card, start the explanation of the cards
content by clicking on the underlined items and a full explanation will appear on the
right hand side.
Step three: Review this material by scrolling downward. When the right hand scroll down
is completed, click on the next underlined item to work through the summary card.
Step four: After completing the last slide, to complete the question for credit for this
module, please close out that module, and advance to the question 2 in
Blackboard,(see next slide), then answer the question and review the answer. Then,
when read, proceed to module #3 where we will complete our work on cardiac
evaluation.
Now link to this website for completion of step 1-3.
http://webmedia.unmc.edu/intmed/geriatrics/reynolds/pearlcards/preop/preoppearlcard.ht
m
Post-test
• A 76-year-old woman who resides in an assisted-living
apartment is admitted to the hospital for right
femoropopliteal bypass surgery. She has experienced
increasing claudication pain, which has confined her to a
wheelchair. Preoperative evaluation, including review of
history, examination, and preoperative testing, reveal the
following: the patient had an uncomplicated inferior wall
myocardial infarction 1 year ago; she has osteoarthritic
changes of both knees; she is a well-controlled, insulindependent diabetic; her blood urea nitrogen level is 56
mg/dL and serum creatinine is 1.4 mg/dL. Her
electrocardiogram shows normal sinus rhythm with Q
waves in leads II, III, and a VF. Hydrate and proceed
with surgery. Order radionuclide angiography. Order
transthoracic echocardiography. Order an exercise
stress test. Order dipyridamole-thallium imaging. Which
of the following is the next correct step?
Which of the following is the next correct
step?
A.
B.
C.
D.
E.
Hydrate and proceed with surgery.
Order radionuclide angiography.
Order transthoracic echocardiography.
Order an exercise stress test.
Order dipyridamole-thallium imaging.
Answer: E. Order dipyridamolethallium imaging.
• The goal of the preoperative clinical evaluation is to establish and
minimize the perioperative risk of the patient. This patient scores 15
points on the Modified Cardiac Risk Index (based on age > 70
years; myocardial infarction > 6 months earlier; poor general
medical status given the elevated blood urea nitrogen) and would be
assigned a class I risk. However, she has three low-risk variables:
age > 70 years, diabetes mellitus, and Q waves on
electrocardiogram. These factors increase her to intermediate-risk
status (3% to 15%) for a perioperative cardiac event. As the patient
is scheduled to undergo vascular surgery, it may be advisable to
delay surgery to further evaluate her potential for cardiac
complications in the perioperative period. Hydration, without
evidence of decreased volume status, is not indicated and may
increase the patient?s risk for perioperative congestive heart failure.
Used with permission from: Murphy JB, et. al. Case Based Geriatrics Review: 500 Questions and
Critiques from the Geriatric Review Syllabus. AGS 2002 New York, NY.
• Neither radionuclide angiography nor
transthoracic echocardiography is
recommended to determine perioperative risk.
Radionuclide angiography is used to assess left
ventricular function. Studies of radionuclide
angiography in predicting perioperative cardiac
complications have found poor predictive
negative test results when patients with normal
left ventricular ejection fraction are evaluated,
and poor predictive positive test results when
patients with low left ventricular ejection fraction
are evaluated. Likewise, transthoracic
echocardiography adds little to the clinical
evaluation in determining risk of cardiovascular
complications.
• Exercise stress testing is commonly used to
screen for coronary artery disease because of its
low cost and wide availability. Unfortunately,
patient-related problems may limit its utility. A
patient with degenerative joint disease,
peripheral vascular disease, previous stroke, or
other mechanical disability may have difficulty in
exercising to meet her target heart rate.
Because of these limitations, exercise stress
testing has a poor predictive value and is not
recommended in these patients for determining
perioperative risk.
• Studies of dipyridamole thallium imaging have
demonstrated its utility in determining the
potential for cardiac complications in
intermediate-risk patients, such as the patient in
this case. A posttest probability of 1% for cardiac
complications is associated with a negative
dipyridamole thallium scan, and the risk for
complications rises to 23% with a positive scan.
Dobutamine stress echocardiography is also
effective in determining the level of risk in
patients with a low score on the Modified
Cardiac Risk Index but one or more low-risk
variables. Patients with a normal dobutamine
stress echocardiography study are at very low
risk for cardiac complications during vascular
surgery, but their risk climbs dramatically with an
abnormal study.
• Patients with normal findings on dipyridamole thallium
imaging or dobutamine stress echocardiography can
proceed with the vascular surgery. Those with abnormal
studies may need to have the nature of their high-risk
state determined. Those with modifiable risk factors
(congestive heart failure, arrhythmia) should have their
medical status optimized prior to surgery. If factors are
not modifiable and surgery is essential, more intensive
perioperative monitoring may be required. In patients
with a high-risk state due to ischemic heart disease, the
need and timing of coronary revascularization must be
determined. While dipyridamole thallium testing allows
the determination of risk and closer monitoring in the
perioperative period, further research is needed to
determine whether this results in improved clinical
outcomes. End