Periopertive assesment and preparation of patient with Cardiovascular Disease

1. Periopertive assesment and
preparation of patient with
Cardiovascular disease
Presented by: Dr Gayathri G
Moderators: Dr Ushakumari
Dr Anoop

3. Why the need for a pre-anaesthetic assessment?

4. • Surgery is a condition of stress.
• The heart may be placed under increased
work load due to tachycardia arising from
pain, blood loss, laryngoscopy and intubation
• Patients suffering from cardiac disease like MI,
cardiac failure are at increased risk of
developing perioperative Major Adverse
Cardiac Events(MACE).

5. GOALS
• Identify patients at risk of heart disease based
on risk factors
• Evaluate the severity of underlying cardiac
disease through history, physical examination
and preoperative testing

6. • Stratify the extent of risk
• Determine the need for preoperative
interventions to minimize the risk of
perioperative cardiac complications.
• Modify the risk of perioperative adverse
events

7. • To minimize costs by testing only the patients
under high risk.
• To formulate a plan for anesthesia
• Plan for adequate post operative treatment.

8. Ischemic heart disease

9. The corner stones of assessment are
• History including current functional status
• Physical examination
• Diagnostic tests
• Knowledge of the planned surgical procedure

10. HISTORY – RISK FACTORS
Non Modifiable
•Age
•Gender
•Family history
Modifiable
• Hypercholestrolemia
• Hypertension
• Diabetes
• Obesity
• Sedentary lifestyle
• Smoking

11. HISTORY
• Presence, severity, and reversibility of CAD
• Angina patterns
• Stable or unstable (new, crescendo, at rest)
• Medications
• Previous myocardial infarction

12. • Myocardial function
– NYHA classification/ DASI/ METS
• H/o Pulmonary edema
• H/o Pulmonary hypertension

13. Dysrhythmias
• Palpitation
Valvular heart disease
• Dyspnea, orthopnea, PND
• Hemoptysis
• Embolic events
• Heart failure
• Arrhythmias

14. • Associated vascular diseases
Cerebral/Carotid/ Aortic/Peripheral vascular
disease – claudication
•Prior cardiac evaluation
Non invasive test
Angiography
• Current medications

15. Current functional status estimation is a crucial
part of pre anaesthetic assessment.

16. • NYHA class I: no limitation of physical activity;
ordinary activity not a cause of fatigue, palpitations, or
syncope
• NYHA class II: slight limitation of physical activity;
ordinary activity resulting in fatigue, palpitations, or
syncope
• NYHA class III: marked limitation of physical activity;
less than ordinary activity resulting in fatigue,
palpitations, or syncope; comfort at rest
• NYHA class IV: inability to do any physical activity
without discomfort; symptoms at rest

18. • DASI is used to calculate the VO2 max from
the daily activities of a patient.
• A questionnaire (yes or no) is answered by the
patient.
• Each question has a particular weightage.
• Total score is obtained by adding together the
weightage of all “yes” questions.

19. VO2 max = 0.43 x DASI score + 9.6.
This divided by 3.5 gives the number of METs.

20. Functional status
One MET = 3.5ml/kg/min
Implies oxygen consumption of a resting adult
40 year old 70 kg
•A cutoff of 4 METS is used for decision making
•<4 METS = ↑ perioperative cardiac risks

22. Functional capacity
• >10 METS Excellent
• 7 to 10 METS Good
• 4 to 7 METS Moderate
• < 4 METS Poor

23. Physical Examination
• Vital signs
• Pulse
– Regularity, radial, carotid, femoral
• Blood pressure
• Pulse pressure
• Respiration

24. Cardiac Examination
• JVP
• Peripheral edema
• Apical impulse –
cardiomegaly
• S3 gallop (↑LVEDP)
• S4(↓ compliance)
• Apical systolic murmur
(papillary muscle
dysfunction)
• Pulmonary edema
• Murmurs

25. Tests
• CXR
• ECG
• Echocardiography
• Exercise testing
• Myocardial perfusion scanning
• Angiography

26. Predicting adverse outcomes from history,
physical and investigations

27. Clinical predictors
• High risk

29. Intermediate clinical predictors
• Mild angina pectoris (Canadian class I or II)
• Prior myocardial infarction by history or
pathologic Q waves
• Compensated or prior congestive heart failure
• Diabetes mellitus
• Renal insufficiency

30. Minor clinical predictors
• Advanced age
• Abnormal ECG (LVH, LBBB, ST-T changes)
• Rhythm other than sinus (e.g., AF)
• Low functional capacity (<4METS)
• History of stroke
• Uncontrolled systemic hypertension

31. Risk indices
1. Goldman
2. Detsky
3. Lee (Revised Cardiac Risk Index)
4. NSQIP MICA
5. NSQIP Surgical Risk Calculator

33. •Detsky et al validated and further modified
Goldman’s cardiac risk index by giving the type
of surgery a separate pretest probability
•He modified the congestive heart failure (CHF)
variables and included recent or previous
myocardial infarction and severity of angina
•Disadvantage- cumbersome to apply

34. •Revised Cardiac Risk Index (RCRI) by Lee et
al in 1999
•Identified 6 independent predictors of adverse
cardiac outcome in patients undergoing
noncardiac surgery

37. Ischemic heart disease, defined as
•H/o myocardial infarction
•H/o or current angina
•Use of sublingual nitroglycerin,
•Positive exercise test
•Q waves on ECG
•Patients who have undergone PTCA or CABG
and who have chest pain presumed to be of
ischemic origin

38. Heart failure, defined as
• Left ventricular failure by physical examination
• History of paroxysmal nocturnal dyspnea
• History of pulmonary edema
• S3 or bilateral rales on physical examination
• Pulmonary edema on chest x-ray

39. • Cerebrovascular disease, defined as
– H/o TIA
– H/o CVA
• Insulin-dependent diabetes mellitus
• Chronic renal insufficiency ,defined as
– S.creatinine >2.0 mg/dL

40. • Web based calculators are also used
• National surgical quality improvement
program myocardial infarction cardiac arrest
• NSQIP MICA and NSQIP
• Not well validated
• Not extensively studied

41. Indications for preoperative cardiac
testing
1. Patients with intermediate clinical predictors
2. Prognostic assessment of patients undergoing
initial
evaluation for suspected or proven coronary artery
disease (CAD).
3. Evaluation of patients with change in clinical
status
4. Evaluation of adequacy of medical treatment
5. Prognostic assessment after an acute coronary
syndrome

42. Noninvasive tests can be divided into
• resting tests,
• exercise tests
• pharmacologic tests with myocardial
perfusion imaging or echocardiography.

43. Tests
• ECG
• Risk of major adverse cardiac events cannot
be predicted

44. In ECG , Look for:
• Myocardial ischaemia / infarction
• Comparison with previous EKG
• ST changes (depression, elevation)
• T wave changes (inversions)
• Q wave (significance, location)
• Chamber enlargement
• LVH (voltage, strain criteria)
• Dysrhythmias
• Conduction abnormality

45. CXR
• Cardiomegaly
• Signs of ventricular dysfunction
• Increased pulmonary vascular markings
• Edema
• Effusions

46. Resting echocardiography
• Simple and inexpensive form of cardiac
imaging
• Indicated for the detection of impaired LV
function and valvular heart disease.

47. Findings
• Regional wall motion abnormalities
– Type – hyperkinesia/akinesia/dyskinesia
– Location –
anterior/septal/lateral/inferior/posterior
• Ejection fraction
• Chamber enlargements / hypertrophy
• Assessment of valve morphology and function
• Assessment of congenital and other diseases

48. Stress tests
• Exercise stress test
• Pharmacological
Dobutamine stress echocardiography
Dipyridamole thallium scintigraphy

49. Exercise testing
• Exercise stress testing is the first screening
step in stress testing of ambulatory patients
• Widely available and inexpensive method of
screening

50. With exercise
•MAP ↑ despite significant ↓ in SVR due to
marked increases in cardiac output as much as
fourfold during maximal exercise.
•The increases in cardiac output are due to
–heart rate (can ↑by upto 300%)
–stroke volume (can↑ by upto 20%)

51. The determinants of ↑ myocardial MVO2
affected by exercise –
• heart rate
• wall tension and
• contractility.

52. This ↑ in oxygen consumption is met by
•↑ in blood flow
•↑ in extraction(minimal)
The ↑ in blood flow is achieved by
• marked vasodilation of coronaries in response
to metabolic demands

53. Impairment of coronary reserve →
• Myocardial ischemia and its sequele,
• Arrhythmias and
• Pump dysfunction

54. Limitations
• Only half of the patients achieve peak heart
rates > 85% of their age-predicted maximum.
• A negative test in a patient who achieves the
targeted heart rate-blood pressure product is
usually associated with low risk for
perioperative cardiac complications.
• Ischemia induced by low-level exercise
indicates high risk.

55. The test has a
• positive predictive value of 18%( 5–81%)
• negative predictive value 97%(90–100%) .

56. Information
• Obtain and document details of exercise stress
test rather than stating it was normal or
abnormal.

57. Parameters
– The peak heart rate,
– systolic blood pressure,
– Rate pressure product (or double product)
– METS
– percent of target heart rate achieved
– ECG changes/ symptoms/arrhythmias occurring
during the test and at recovery phase.

58. Intraoperatively the double product should
remain below the ischemic threshold.

59. Pharmacologic testing
Dobutamine stress echocardiogram (DSE) -
• Dobutamine ↑ heart rate and inotropy
• Echocardiography is performed at discrete
points to detect new or worsened regional
wall motion abnormalities

60. Dobutamine stress echocardiogram has
• Positivepredictive value of 15% (7–25%)
• Negative predictive value of 99%( 93–100)

61. • The extent and severity of new or worsening
RWMA, particularly at low ischemic thresholds,
is predictive of both short- and long-term
outcome
• Dobutamine testing should be avoided in
patients with significant arrhythmias, marked
hypertension or hypotension, and suspected
critical aortic stenosis.

62. • Dipyridamole thallium scanning (DTS)
Dipyridamole decreases adenosine uptake
• Adenosine causes coronary vasodilatation
preferentially distributing blood to normal
coronaries and reducing blood flow distal to
coronary stenosis.
• Myocardial imaging with thallium initially and
after several hours demonstrates defects in
myocardium at risk.

63. Prior To testing, patients should avoid
theophylline preparations and caffeine d/t
antagonistic effect on dipyridamole.
Side effects include
• bronchospasm,
• chest pain
• headache
• dizziness;
Reversed by IV aminophylline.

64. This test has a
• positive predictive value - 16% ( 6–67%)
• negative predictive value - 99%(98–100%)

65. • Angiogram
• Cardiac catheterisation

66. Surgical Procedures
Emergency procedure
One in which life or limb is threatened if not in
the operating room where there is time for no
or very limited or minimal clinical evaluation,
typically within <6 hours.

67. Urgent procedure
One in which there may be time for a limited
clinical evaluation, usually when life or limb is
threatened if not in the operating room,
typically between 6 and 24hours

68. Time-sensitive procedure
One in which a delay of >1 to 6 weeks to allow
for an evaluation and significant changes in
management will negatively affect outcome.
Most oncologic procedures would fall into this
category.

69. Elective procedure
One in which the procedure could be delayed
for up to 1 year

70. How to proceed ???
Step 1:
• Patients with risk factors for or known CAD,
determine the urgency of surgery.
• If an emergency, then determine the clinical
risk factors that may influence perioperative
management and
• proceed to surgery with appropriate
monitoring and management strategies based
on the clinical assessment

71. Step 2:
• If the surgery is urgent or elective,
• determine if the patient has an ACS.
• If yes, then refer patient for cardiology
evaluation and management according to
GDMT according to the UA/ NSTEMI and
STEMI CPGs.

72. Step 3:
• If the patient has risk factors for stable CAD,
then
• estimate the perioperative risk of MACE on
the basis of the combined clinical/surgical risk
with NSQIP risk calculator /RCRI

73. Step 4
• If the patient has a low risk of MACE (<1%),
then no further testing is needed, and the
patient may proceed to surgery.

74. Step 5
• If the patient is at elevated risk of MACE,
• then determine functional capacity with an
objective measure or scale such as the DASI
• If the patient has moderate, good, or
excellent functional capacity (>4 METs), then
proceed to surgery without further evaluation

75. Step 6
• If the patient has poor (<4 METs) or unknown
functional capacity,
• then the clinician should consult with the patient
and perioperative team to determine whether
further testing will impact patient decision
making (e.g., decision to perform original surgery
or willingness to undergo CABG or PCI, depending
on the results of the test) or perioperative care.

76. • If yes, then pharmacological stress testing is
appropriate.
• In those patients with unknown functional capacity,
exercise stress testing may be reasonable to perform.
• If the stress test is abnormal, consider coronary
angiography and revascularization
• The patient can then proceed to surgery with GDMT or
consider alternative strategies, such as noninvasive
treatment of the indication for surgery (e.g., radiation
therapy for cancer) or palliation.
• If the test is normal, proceed to surgery according to
GDMT

77. Step 7:
• If testing will not impact decision making or
care, then proceed to surgery according to
GDMT
• or consider alternative strategies, such as
noninvasive treatment of the indication for
surgery (e.g., radiation therapy for cancer) or
palliation.

80. ECHOCARDIOGRAPHY
• It is reasonable for patients with dyspnea of
unknown origin to undergo preoperative
evaluation of LV function.

81. Class IIa
• It is reasonable for patients with HF with
worsening dyspnea or other change in clinical
status to undergo preoperative evaluation of LV
function.
CLASS IIb
• Reassessment of LV function in clinically stable
patients with previously documented LV
dysfunction may be considered if there has been
no assessment within a year.
CLASS III: NO BENEFIT
• Routine preoperative evaluation of LV function is
not recommended

82. Exercise Stress Testing for Myocardial Ischemia and Functional
Capacity: Recommendations
CLASS IIa
• For patients with elevated risk and excellent (>10 METs)
functional capacity, it is reasonable to forgo further exercise
testing with cardiac imaging and proceed to surgery
CLASS IIb
• For patients with elevated risk and unknown functional
capacity, it may be reasonable to perform exercise testing to
assess for functional capacity if it will change management

83. • For patients with elevated risk and moderate to
good (>4 METs to 10 METs) functional capacity, it
may be reasonable to forgo further exercise
testing with cardiac imaging and proceed to
surgery
• For patients with elevated risk and poor (<4 METs)
or unknown functional capacity, it may be
reasonable to perform exercise testing with
cardiac imaging to assess for myocardial ischemia
if it will change management. CLASS III: NO
BENEFIT
• Routine screening with noninvasive stress testing
is not useful for patients at low risk for noncardiac
surgery

84. Cardiopulmonary Exercise Testing:
Recommendation
CLASS IIb
• patients undergoing elevated risk procedures
in whom functional capacity is unknown

85. Pharmacological Stress Testing
CLASS IIa
• It is reasonable for patients who are at an elevated risk
for noncardiac surgery and have poor functional
capacity(<4 METs) to undergo noninvasive
pharmacological stress testing (either dobutamine
stress echocardiogram [DSE] or pharmacological stress
MPI) if it will change management
CLASS III: NO BENEFIT
• Routine screening with noninvasive stress testing is not
useful for patients undergoing low-risk noncardiac
surgery

86. HYPERTENSION
• Defined by 2 or more arterial BP mesurements
more than 140/90 mmHg
• Prevalence : 28 to 32 % in India
• Duration and severity of HTN highly correlates
with subsequent end organ damage,
morbidity and mortality

87. Pathophysiology – 1o HTN
• Autonomic Nervous system
– Dysregulation of baroreceptor or chemoreceptor
reflex pathways
• RAAS
– Dysregulated renin release → ↑renin →AT -2
overproduction→ ↑aldosterone → HTN
• Endogenous vasodilator vasoconstrictor
balancce
– Vasoconstrictors: Endothelins
– Vasodilators : NO , ANP, BNP, Urodilatin

88. IMPACT OF C/C HTN ON ORGAN
FUNTION

89. CVS
• Loss of arterial elasticity and compliance
• ↑SBP – due to arterial stiffening
• ↑ Afterload →Conc LVH to minimise wall
stress → ↑ Myocardial O2 demand
• loss of diastolic augmentation - ↓DBP , ↓
coronary perfusion
• Widening of pulse pressure

90. • Untreated HTN leads to myocardial
ishchemia/infarction
• Ultimately both systolic and diastolic
performance decline
• Subset may have isolated diastolic failure with
peserved ejection fraction

91. CNS
• Ischemic / Haemorrhagic brain injury
• Luminal narrowing of carotids → flow
insufficiency
• Autoregulation shifted to right→
hytpotension worsens ischemia

92. Renal system
• Chronic renal insuffiency is a common sequele
of HTN

93. END ORGAN DAMAGE IN HTN
Vasculopathy
• Endothelial dysfunction
• Remodelling
• Generalised atherosclerosis
• Ateriosclerotic stenosis
• Aortic aneurysm
Cerebrovascular damage
• A/c Hypertensiv
encephalopathy
• CVA –ishchemic/Hgic
• Vascular dementia
• Retinopathy
Heart Disease
• LVH
• AF
• Coronary microangipathy
• CAD, MI
• Heart failure
Nephropathy
• Albuminuria
• Proteinria
• Chronic renal insufficeincy
• Renal failure

94. Why Preop evaluation in HTN
• Identify causes of HTN
• Coexisting risk factors
• Identify end organ damage

95. History
• HTN in the young – look for secondary causes
– Hyperthyroidsm
– Coarctation of aorta
– Pheochromocytoma
– Illicit Drug use
• End organ damage
– DOE
– H/o TIA, CVA, DM , Renal disease, Recent MI, CCF
– Angina/Syncope/palpitation/episodic tachycardia
– Drugs

96. Examination
• CVS
– BP measurement in both arms
– Examination of all peripheral pulses
– Auscultation for bruit
– Signs of ↑ intravascular volume
– Thyroid gland

97. Investigations
• Further testing directed by history and
examination, surgical procedure
• Long standing , poorly controlled Htn – ECG
,BUN, S.Creatinine
• Pts on diuretics – Electrolytes
• Thyroid dysfunction – TFT

98. Pts with e/o End organ damage
• ECG – LVH /Strain pattern
• H/o CVA , TIA
• Elevated S.Creatinine
These set of pts may undergo further testing
based on Risk of surgery, urgency of
surgery,funcional class of the pt

99. How to proceed
• Little evidence of admission blood pressures
<180/110 mmHg causing any adverse
perioperative complications.
• There is little benefit to be obtained by
deferring or cancelling elective surgeries if the
blood pressure is <180/110
• Elective surgery should be delayed for severe
HTN – SBP > 200 or DBP >115

100. • The ACC and AHA list ‘uncontrolled systemic
hypertension’ as a minor predictor that has
not been shown to independently increase
perioperative risk
• Guidelines from the AAGBI and the BHS state
that in the absence of organ damage, BP
<180/110 does not warrant cancellation or
deferment of elective cases in an attempt to
optimise the blood pressure

101. RECOMMENDATIONS
• If the documented blood pressure in primary
care is <160/100 mmHg with or without
optimal antihypertensive treatment in the last
1 year, then further measurements and
assessments need not be performed in the
pre-anaesthetic clinic (PAC)

102. • Any measured BP <180/110 mmHg without
e/o organ damage can be cleared for surgery
without the need for further assessment.
• E/o organ damage –ECG changes, a h/o TIA
and/or stroke or raised S.creatinine
• Additional testing is rarely required unless the
patient is undergoing a high-risk surgery such
as vascular surgery

103. • The guidelines suggest that due to limited
evidence, the decision to proceed with
surgery in pts with BP > 180/110 should look
at other factors such as:
– associated comorbidities
– functional class of the patient
– urgency of the surgery

104. DRUGS
• All long term antihypertensives to be
continued on DOS
• Exceptions : ACEI, ARB

105. Treatment of HTN
• Lifestyle modifications
• Pharmacological
• Rx of secondary HTN

106. Pharmacological Rx – JNC 8
• Age >60 - BP goal <150/90
• Age 30 -59 DBP goal <90
• Initial Rx – ACEI / ARB / CCB / Thiazide
diuretics
• Beta blockers tend to be reserved for pts with
CAD/ tachyarrythmias/ as component of
multidrug theapy in resistant HTN

107. • Resistant HTN – uncontrolled BP despite 3 or
more antihypertensives including a non K+
sparing diuretic or need for 4 or more drugs to
achieve control
• Refractory HTN- uncontrolled BP on 5 or more
drugs

108. How to proceed
• 50 yr old man with HTN on irregular Rx
coming for parotidectomy .
• O/E BP - 170/100

109. • 55 year old lady for hysterectomy – h/o HTN
on regular Rx
• BP – 190/120

110. • 25 year old male coming for RIH repair
• BP – 150/110

111. PATIENTS WITH CORONARY STENTS
•The presence and type (drug-eluting or bare
metal) of any coronary stent must be identified
•Subsequent management must be performed
in collaboration with a cardiologist.

112. Bare Metal Stent
•Recent bare metal stent , defined as occurring
within the previous 30 days, should absolutely
not undergo elective surgery.
•If urgent surgery is needed, strong
consideration is given to continuing dual
antiplatelet therapy throughout the
perioperative period

113. The major concern with premature
discontinuation of DAPT – risk of precipitating
catastrophic
•stent thrombosis,
•MI, or
•death.

114. Drug Eluting stents
• Elective Sx not recommended 1 yr after DES
• Urgent Sx – strong recommendation for
continuing DAPT

115. •Surgical procedures in the critical time windows, aspirin
is to be continued throughout the perioperative period,
and thienopyridine (typically clopidogrel) therapy is
restarted as soon as possible postoperatively.
•UFH and LMWH are not appropriate for “bridging”
patients with coronary stents who have been withdrawn
from all antiplatelet therapy.

117. HEART FAILURE
• Decompensated heart failure is also a high-risk characteristic
that warrants postponement of surgery for all except
lifesaving emergency procedures.
• It may be systolic or diastolic failure
• IHD is the most common cause for systolic dysfunction.

118. The goal in the preoperative evaluation is to
identify and minimize the effects of heart
failure.
.
Patients with decompensated
heart failure feel like they are “suffocating” or
have “air hunger.”

119. HISTORY
•Recent weight gain
•Shortness of breath
•Fatigue
•Orthopnea
•PND
•Nocturnal cough,
•Peripheral edema,
•Hospitalizations, and
•Recent changes in
management

120. Physical examination
•Third or fourth heart sounds
•Tachycardia
•Laterally displaced apical beat
• Rales
• Jugular venous distention
• Ascites
• Hepatomegaly,
• Peripheral edema.

121. Investigations
• ECG
• Sodium , Potassium
• BUN, creatinine
• BNP
• CXR – if pulmonary odema is suspected

122. BNP - uses
•The plasma concentration of BNP is a powerful marker
of cardiovascular risk in nonsurgical patients
•Preoperative BNP levels predict risk for cardiac
complications and death.
•Screening individuals
whose functional capacity is difficult to estimate
•Specifically, a low BNP concentration -low
perioperative cardiac risk

123. ECHOCARDIOGRAPHY
The current ACCF/AHA guidelines recommend
preoperative echocardiography to assess dyspnea of
unknown origin or any change in clinical symptoms

124. Left ventricular ejection fraction
Normal : >50%;
Mildly diminished 41% to 49%
Moderately diminished 26% to 40%
Severely diminished <25%

125. DRUGS
•Medical therapy, including β-adrenergic blockers,
hydralazine, nitrates, and digoxin, must be optimized
and continued preoperatively.
•ACEIs, ARBs,and diuretics (including aldosterone
antagonists such as spironolactone) may be beneficial,
even on the day of surgery.
•Continuation of loop diuretics on the day
of surgery does not increase the risk of intraoperative
hypotension or adverse cardiac events.

126. selective continuation or discontinuation of
these drugs depends on
• intravascular volume
• hemodynamic status of the patient,
• degree of cardiac dysfunction,
• anticipated surgical procedure intravascular
• volume challenges

127. Continuing all medications for patients with severe
dysfunction who
are scheduled for minor procedures is probably best.

129. MURMURS AND VALVULAR
ABNORMALITIES
Goals in preoperative assessment
• Determining the cause of cardiac murmurs
• Identifying significant murmurs

130. Indications for echo include
• Increased age
• Risk factors for heart disease
• Abnormal heart sounds
• History of rheumatic fever
• Anorectic drug use,
• Evidence of excessive intravascular volume
• Pulmonary disease
• Cardiomegaly
• Abnormal ECG

133. PROSTHETIC HEART VALVES
Important preoperative issues :
• Determinations of the underlying condition requiring
replacement
• Type of prosthesis
• Need for anticoagulation
• Anticoagulation management of such patients in the
perioperative period.

134. In descending order of risk, the risk of thrombosis is greatest
with
• Multiple valves
• Mitral valve replacements
• Aortic valve replacements.

135. Highest risk
• Caged-ball valves (e.g., Starr-Edwards) have the
IntermediateRisk
• Single tilting-disk valves (e.g., Björk-Shiley,
Lowest risk
• Medtronic-Hall, Omnicarbon) - bileaflet tilting-
disk prostheses (e.g., St. Jude, CarboMedics,
Edwards Duromedics).
Do not require long-term anticoagulation -
Bioprosthetic valves
• Carpentier-Edwards or Hancock

136. • Prophylaxis for infective endocarditis is recommended for
specific procedures.
• Anticoagulants - Decisions about stopping /duration of
discontinuance/ the use of “bridging” /type of bridging agent
are made in conjunction with the treating cardiologist and
surgeon.

137. INFECTIVE ENDOCARDITIS
PROPHYLAXIS
Prophylaxis is now recommended
only for patients with cardiac conditions with
the highest risk of major adverse outcomes.
No prophylaxis is recommended for upper and lower
gastrointestinal diagnostic procedures

138. • prophylaxis only for at-risk patients undergoing urinary
tract procedural manipulation (e.g., cystoscopy) in the
presence of enterococcal urinary infection or
colonization
• Patients who are having procedures on infected skin or
musculoskeletal tissues plus one of the conditions listed
below shall get prophylaxis.

140. RHYTHM DISTURBANCES
• New-onset atrial fibrillation,
• uncontrolled atrial fibrillation (rates >100 beats/minute)
• symptomatic bradycardia
• high-grade heart block (second- or third-degree heart
block), warrants postponementof elective procedures and
referral to cardiology for further evaluation.

141. First-degree AV block is defined as a PR interval exceeding
0.20 msec with an HR of 50 to 100 beats/minute, and
it is generally benign.

142. • Second-degree heart block occurs when the PR interval
exceeds 0.20 msec and some atrial beats are blocked,
resulting in a dropped or missing QRS complex after a P wave.
• Two types of second-degree block exist. Mobitz type I, or
Wenckebach block, is more benign, rarely progresses to
complete heart block, and is easily responsive to atropine.
• Because of AV nodal delay, it is characterized by progressive
lengthening of the PR interval until the dropped beat occurs.

143. • Mobitz type 2 block results from an infranodal block, can
progress to complete heart block, and is generally treated
with a pacemaker unless thecondition is secondary to a
reversible cause such as ischemia or drugs.
• Mobitz type II block is characterized by a fixed, prolonged
PR interval that does not change before the dropped QRS
complex.

144. Third-degree or complete heart block
• complete dissociation between the atrial and ventricular
beats
• requires a pacemaker unless a reversible source is identified.
Two general factors are considered when determining the need
for a pacemaker:
• An arrhythmia associated with symptoms
• Location of the conduction abnormality.

145. BUNDLE BRANCH BLOCKS
• They can be normal variants, or they can result from
aging or fibrosis of the conducting system, ischemia,
pulmonary disease, radiation, and Cardiomyopathies.
• A recent onset (or no previous evaluation) of BBB
prompts a more extensive consideration of cardiac
risk.
• A previous ECG for comparison helps differentiate a
long-standing abnormality from a new development.

146. • If the history and physical examination do not suggest
significant pulmonary, congenital, or ischemic heart
disease or Brugada syndrome, no further evaluation of an
isolated RBBB is warranted.
• An RBBB in a patient with pulmonary symptoms
(including pulmonary hypertension) may suggest severe
respiratory or vascular compromise.
• Consideration should be given to pulmonary evaluation
and echocardiography if intermediate- or high-risk
surgery is planned.

147. • A prolonged QT interval should prompt an evaluation of
electrolytes, magnesium, and calcium, as well as a search for
potentiating drugs.
• Syncope, presyncope, or a family history of sudden death in a
patient with a prolonged QT interval mandates cardiology
consultation.

148. ATRIAL FIBRILLATION
• Atrial fibrillation can occur in increased age, thyrotoxicosis,
and valvular heart disease.
• It also occurs in the perioperative setting.
• Atrial fibrillation can be intermittent (i.e., paroxysmal),
persistent (i.e., capable of being cardioverted), or
permanent (i.e., cannot be converted).

149. • In general, HR control is more important than rhythm control.
• Patients with rapid ventricular rates, exceeding 100
beats/minute, require rate control before elective surgical
procedures.

150. • Most patients with atrial fibrillation require long-term
anticoagulation,which entails perioperative management.
• The requirement for bridging anticoagulation therapy
during the perioperative period is based on a patient’s
expected risk for stroke related to the atrial fibrillation.
• Patients with atrial or ventricular thrombi, mechanical heart
valves, or a history of previous thromboembolic events are
at higher risk for stroke.

151. CHADS2 (congestive heart
failure, hypertension, age, diabetes, stroke) index can
more accurately estimate the risk of stroke in individuals
with nonrheumatic atrial fibrillation.

152. This index consists of five components:
• Congestive heart failure,
• Hypertension (BP >140/90 mm Hg)
• Age 75 years or older,
• Diabetes
• Prior thromboembolism (including stroke or transient
ischemic attack).

153. • Guidelines from the American College of Chest Physicians
recommend consideration of bridging therapy for patients
who have CHADS2 scores of 3 or more.
• In general, the perioperative management of a patient’s
long-term anticoagulant therapy is made in concert with
the treating physician.
• Any β-adrenergic blockers, digoxin, calcium channel
blockers, or antiarrhythmic medications used for atrial
fibrillation should be continued perioperatively.

154. VENTRICULAR ARRHYTHMIAS
• Ventricular ectopic beats can be differentiated from atrial
ectopic beats by a wide QRS complex (>0.12 msec) and lack of
a P wave.
• Classified as benign, potentially lethal and lethal.

155. Benign:
Isolated ventricular premature beats (VPBs)
without associated heart disease
• No need for further evaluation
• No risk of sudden cardiac arrest

156. Potentially lethal:
• More than 30 VPBs/hour or
• Non sustained ventricular tachycardia with underlying
• Heart disease
• Requires cardiology evaluation with echocardiography/stress
testing/coronary angiography/ electrophysiology testing
• Moderately high risk of sudden cardiac arrest; possible benefit
from an ICD

157. Lethal:
• Sustained ventricular tachycardia,
• Ventricular fibrillation
• Syncope
• Hemodynamic compromise
• Associated with VPBs with underlying heart disease and
• Depressed cardiac function

158. • Requires cardiology evaluation with echocardiography, as
well as possible stress testing, coronary angiography, and
electrophysiology testing
• High risk of sudden cardiac arrest; likelihood of benefiting
from an ICD
• Reversible causes such as hypokalemia, ischemia, acidosis,
hypomagnesemia, drug toxicity, and endocrine dysfunction
must be sought out and treated.
• Antiarrhythmic medication must be continued
perioperatively.

159. PROLONGED QT SYNDROME
• The long QT syndrome (LQTS) is a disorder of myocardial
repolarization that can be either genetic or acquired.
• It is associated with torsades de pointes, a polymorphic
ventricular tachycardia with frequent variations of the QRS
axis or morphology.
• Symptoms include palpitations, syncope, seizures, and sudden
cardiac death.

160. • The QT interval is measured in lead II of a 12-lead ECG
from the onset of the QRS complex to the end of the T
wave.
• Because the QT interval varies inversely with HR, the QTc
(corrected for HR) can be calculated (QTc = QT interval +
square root of the RR interval

161. • In children 1 to 15 years old, a QTc exceeding 0.46 seconds is
considered prolonged.
• QTc is prolonged if exceeding 0.47 seconds in women and 0.45
seconds in men.

162. • LQTS results can also be acquired due to hypokalemia,
hypomagnesemia, eating disorders, and drugs such as
antiarrhythmic drugs (quinidine) and psychotropic drugs
(haloperidol, droperidol, methadone).
• Treatment includes beta adrenergic blockers, icd implantation
and correction of underlying disorders.

163. BRUGADA SYNDROME
Brugada syndrome is a rare cause of
sudden cardiac arrest that occurs without structural heart
disease.
Most affected individuals are of Asian ethnicity.

164. Brugada syndrome is an autosomal dominant disorder
that is much more common in men and rarely diagnosed
in children.
It is associated with a peculiar ECG consisting
of a pseudo-RBBB and persistent ST-segment elevation in
V1 to V3. The widened S wave in the left lateral
leads, as is typical of usual RBBB, is absent in most
patients with Brugada syndrome.
DRUGS including propofol and bupivacaine are associated with
adverse outcome with this syndrome

166. The most significant clinical manifestations
are ventricular arrhythmias, syncope, and sudden
death.
These patients may also be at increased risk of
atrial arrhythmias, especially atrial fibrillation.
The syndrome has no proven pharmacologic treatment.

167. • ICD implantation is the standard of care