1. health and fitness
2. disease
3. heart disease

Cardiac Conduction Disease
Perioperative New Onset Complete
Heart Block
Matthew C. Wixson, MD
7 February 2014
University of Michigan
Department of Anesthesiology
Puerto Vallarta
Objectives
• Case presentation
• Review basic cardiac conduction pathway
• Review various types of heart block and their
implications
• Review current guidelines of screening patients
with bradyarrhythmias and conduction
abnormalities
• Educate regarding evidence supporting current
practice guidelines
• Review basic management of heart block in the
urgent/emergent setting
Case Presentation
• S.B is a 92 year old ASA 2 male who
presents for elective laparoscopic right
inguinal hernia repair
• PMHx
–
–
–
–
–
Mild aortic regurgitation
LBBB
HTN
GERD
Transverse and descending colon CA
• PSHx
– Inguinal hernia repair
– Colon resection
– Moh’s resection of SCC
• Medications
–
–
–
–
–
–
–
ASA
Vitamin B12
Losartan
MVI
Omeprazole
Tamsulosin
Triamterene-HCTZ
• Allergies
– Lisinopril
– Sulfa antibiotics
• SHx
– Former pipe smoker (45 years, quit 1990) No EtOH or
illicit drug use
• Studies: EKG– sinus rhythm with
occasional PVCs, LBBB
• TTE (5/2013): EF ~65%, moderate aortic
regurgitation, grade 1 diastolic
dysfunction
Preoperative EKG
Clinical Course
• Patient presented for surgery on 7/23/2013
• Intraoperative Record: without issues until
reversal given (glycopyrrolate 0.4mg,
neostigmine 2.5mg)
• Patient noted to become bradycardic with
HR ~40 beats/minute
PACU Course
• Arrived to PACU; report received that
patient had been bradycardic since
emergence
• Had received 0.2mg glycopyrrolate prior
to transfer from OR  PACU
• Arrival vitals:
–
–
–
–
HR 41 beats/minute
BP 104/48 mmHg
SpO2 (6L NC) 99%
T 36.4 C
Differential Diagnosis
Investigations
• EKG
• Cardiac labs
• Telemetry
PACU EKG
• Patient noted to remain with HR 30s-40s
beats/minute throughout PACU course
• Had several 4-8 second sinus pauses
noted on telemetry
• Patient hemodynamically stable and
mentating throughout sinus pauses
• Transcutaneous pacing pads placed on
patient and LifePak20 attached
Telemetry
Cardiology/EP Consult
• Initial evaluation: patient noted to be in
complete heart block
– Requested access for transvenous pacing (if
needed)
• Patient admitted to SICU for further
hemodynamic monitoring
– 6 Fr catheter placed into IJ
– Arterial line placed
– Asymptomatic overnight
SICU EKG
Follow-up
• Uneventful atriobiventricular pacemaker
placement on POD#1
• Episode of atrial fibrillation while
hospitalized
– Resolved with amiodarone
• Patient seen in Cardiology clinic and
doing quite well
Pacemaker EKG
Cardiac Conduction System Review
• Major features of EKG
–
–
–
–
–
1
P wave, QRS complex, and T wave
PR interval
PR segment
ST segment
QT interval
Cardiac Conduction
SA Node
A V Node
Bundle of His
Left Bundle
L A nterior
Hemibundle
Right
Bundle
Image courtesy B. Woodcock
L Posterior
Hemibundle
Types of Heart Block
First Degree
2
Types of Heart Block
Second Degree Type I
2
Types of Heart Block
Second Degree Type II
Image courtesy B. Woodcock
Types of Heart Block
Third Degree
2
Bundle Branch Block
• Any conduction block in the His-Purkinje
system SA Node
A V Node
Bundle of His
Left Bundle
L A nterior
Hemibundle
Right
Bundle
L Posterior
Hemibundle
Bundle Branch Block
• Any conduction block in the His-Purkinje
system SA Node
A V Node
Bundle of His
Left Bundle
L A nterior
Hemibundle
Right
Bundle
L Posterior
Hemibundle
Bundle Branch Block
• Any conduction block in the His-Purkinje
system SA Node
A V Node
Bundle of His
Left Bundle
L A nterior
Hemibundle
Right
Bundle
L Posterior
Hemibundle
Bundle Branch Block
• Any conduction block in the His-Purkinje
system SA Node
A V Node
Bundle of His
Left Bundle
L A nterior
Hemibundle
Right
Bundle
L Posterior
Hemibundle
Bundle Branch Block
• Any conduction block in the His-Purkinje
system SA Node
A V Node
Bundle of His
Left Bundle
L A nterior
Hemibundle
Right
Bundle
L Posterior
Hemibundle
Bundle Branch Block
• Any conduction block in the His-Purkinje
system SA Node
A V Node
Bundle of His
Left Bundle
L A nterior
Hemibundle
Right
Bundle
L Posterior
Hemibundle
Bundle Branch Block
Recognition
• Right Bundle Branch Block
– R and R’ in leads V1 or V2
• Left Bundle Branch Block
– R and R’ in leads V5 or V6
• Axis Deviation
– Simple rule: thumb test
Screening Guidelines
ASA
Screening Guidelines
ACC/AHA (2007)
“High-grade cardiac conduction abnormalities, such as
complete atrioventricular block, if unanticipated, can
increase operative risk and may necessitate temporary or
permanent transvenous pacing. On the other hand,
patients with intra- ventricular conduction delays, even
in the presence of a left or right bundle-branch block,
and no history of advanced heart block or symptoms
rarely progress to complete heart block perioperatively.”
3
• Circulation 1978
– 44 patients undergoing
52 operations
– 6 temporary
pacemakers (TV)
placed due to PR
prolongation on
preoperative EKG
– 1 episode of transient
CHB observed
– 2/6 with TV
pacemaker had
ventricular irritability
4
• Retrospective study of patients with
– Prolonged PR interval >0.2s PLUS
– RBBB and LAHB (left anterior hemiblock) OR LBBB
• 76 patients underwent general, local, or spinal
anesthetic
• Group 1 (RBBB and LAHB)
– 1 patient with sinus bradycardia responsive to atropine
• Group 2 (LBBB)
– 3 patients with sinus bradycardia responsive to atropine
– 3 patients with prophylactic TV pacemaker inserted preoperatively, none of which were utilized
• Conclusion: risk>benefit of placing TV pacer
5
• Prospective study at University of Ulm, Germany
• Aim: to determine whether presence of 1st degree AV
block increases risk of progression to CHB
• 103 patients with bifascicular or LBBB
– Group 1: 56 patients without AV prolongation
– Group 2: 47 patients with AV prolongation
• Operations under general or regional anesthesia
• Primary endpoint: progression to Mobitz Type II or CHB
• Secondary endpoint: asystole >5s or severe bradycardia
(<40 bpm) with hemodynamic compromise
6
Results
• Group 1
– Two patients progressed to Wenkebach
– Three patients had asystole >5 seconds
• One progressed to cardiac arrest and was resuscitated
• Group 2
– Four patients with HR <40 bpm and hemodynamic
compromise
• All responsive to atropine
• Conclusions: progression is rare
– Patients with pre-existing CAD more at risk
• Retrospective review of >34,000 cases
• 279 patients had complete RBBB
– 70/279 had complete RBBB with left or right AD
• Results
– 1 patient progressed to CHB
– On-pump CABG
• Conclusion: prophylactic placement of gel pads is
not cost-effective
7
• Prospective study
– Enrollment criteria: asymptomatic
bifascicular block OR left bundle branch
block
– Concurrent 1st degree AV block
• Preoperative pacing pads
– Increased milliamperes until capture
obtained
– Scored patient’s pain level
8
Results
• 37/39 patients successfully paced
– Two patients did not have capture at 120mA
– One patient required
• 5mg midazolam
• 300mcg fentanyl
• Assistance with ventilation
– Could not increased further due to patient
discomfort
– 92% reported moderate to intolerable
discomfort
• No block progression in any patients
Atropine
•
•
•
•
•
•
Anticholinergic (parasympatholytic)
Useful for symptomatic bradycardia
Increases SA nodal rate and automaticity
Increased induction via AV node
Dose 0.5-1.0mg q3-5 minutes
Not helpful in 2nd degree Type II block
(Mobitz II) or CHB
– Block is normally below AV node in those
rhythms
12
Management of Complete Heart
Block
• Transcutaneous Pacing (TCP)
– Non-invasive
– Fast
– Can initiate while waiting for response to
drugs
– Useful in hemodynamic instability due to
bradycardia
– Difference between electrical vs. mechanical
capture
12
TCP Diagram
Image courtesy B. Woodcock
Image courtesy B. Woodcock
Transvenous Pacing
• More useful for longer-term pacing
• Catheter placed in right ventricle
– Can place in right atria if atrial pacing necessary
• Venous access
– IJ
– Subclavian
– Femoral vein
• If prosthetic tricuspid valve, access can be
obtained via left side through coronary sinus
13
Complications of TV Catheter
Placement
•
•
•
•
•
•
•
•
•
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•
13
Pneumothorax
Hemothorax
Arterial puncture
Air embolism
Serious bleeding
Myocardial perforation
Cardiac tamponade
Nerve Injury
Thoracic duct injury
Infection
Arrhythmia
Indications for Permanent
Pacemaker
• Class 1
– Generally agreed pacing is indicated
• Complete or advanced second degree heart block
with symptomatic bradycardia
• Persistent complete or advanced second degree
heart block following MI
• Sinus node dysfunction with symptomatic
bradycardia
• Class II
– Pacemakers frequently used but
consensus as to necessity is not clear
• Asymptomatic 2º or complete AV block
– HR > 40
• Asymptomatic sinus node dysfunction
– HR > 40
• Class III
–Generally agreed pacing is not
indicated
• First degree AV block
• Transient post-MI AV block without
bundle branch block
• Asymptomatic fascicular blocks without
2nd or 3rd degree AV block
Final Thoughts
• Was glycopyrrolate/neostigmine
imbalance causative?
• Should we have given atropine?
• Is it worth placing transcutaneous pads
on all patients at risk?
References
1. Sinus Rhythm Labels. www.wikipedia.com/commons
2. Gomella LG, Haist SA. Clinician’s Pocket Reference, Eleventh Edition.
3. ACC/AHA GuidelineACC/AHA 2007 Guidelines on Perioperative Cardiovascular Evaluation and Care for
Noncardiac Surgery. Circulation.2007; 116: e418-e500
4. J O Pastore, P M Yurchak, K M Janis, J D Murphy and L M Zir. The risk of advanced heart block in surgical patients
with right bundle branch block and left axis deviation. Circulation. 1978;57:677-680
5. Mikell FL, Weir EK, Chesler E. Perioperative risk of complete heart block in patients with bifascicular block and prolonged
PR interval. Thorax 1981; 36: 14-17
6. Gauss A, Hubner C, Radermacher P, Georgieff M, Schutz W. Perioperative risk of complete heart block in patients with
bifascicular block and prolonged PR interval. Anesthesiology 1998; 88: 679-87
7. Okamoto A, Inoue S, Tanaka Y, Kawaguchi M, Furuya H. Application of prophylactic gel-pads for transcutaneous
pacing in patients with complete right bundle-branch block with axis deviation when surgical procedures are performed: 10year experience from a single Japanese university hospital. J Anesth (2009) 23:616–619
8. Gauss A, Hubner C, Meierhenrich R, Rohm HJ, Georgieff M, Schutz W. Perioperative transcutaneous pacemaker in
patients with chronic bifascicular block or left bundle branch block and additional first-degree atrioventricular block. Acta
Anaesthesiol Scand 1999; 43: 731–736.
9. Maniya R, Aono J, Manabe M. Complete atrioventricular block. Canadian J Anesthesia 1999; 46:3, 265-67
10. Thomson IR, Dalton BC, Lappas DG, Lowenstein E. Right Bundle-Branch Block and Complete Heart Block Caused
by the Swan-Ganz Catheter. Anesthesiology 1979; 51: 359-62
11. Unnikrishnan D, Idris N, Varshneya N. Complete heart block during central venous catheter placement in a patient with
pre-existing left bundle branch block . British Journal of Anaesthesia 91 (5): 747±9 (2003)
12. Giesecke M, Hosur S. Chapter 55. Cardiopulmonary Resuscitation. In: Butterworth IV JF, Butterworth IV JF,
Mackey DC, Wasnick JD, Mackey DC, Wasnick JD, eds. Morgan & Mikhail's Clinical Anesthesiology. 5th ed. New
York: McGraw-Hill; 2013. http://www.accessmedicine.com.proxy.lib.umich.edu/content.aspx?aID=57239900. Accessed
September 22, 2013.
13. Hongo RH, Goldschlager N. Chapter 22. Conduction Disorders & Cardiac Pacing. In: Crawford MH, ed.
CURRENT Diagnosis & Treatment: Cardiology. 3rd ed. New York: McGraw-Hill; 2009.
http://www.accessmedicine.com.proxy.lib.umich.edu/content.aspx?aID=3648856. Accessed September 22, 2013.
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