This document discusses cardiac arrhythmias that can occur after thoracic surgery. It identifies the most common arrhythmias as atrial fibrillation, supraventricular tachyarrhythmias, ventricular arrhythmias, and conduction disturbances. Potential mechanisms for these arrhythmias include surgical trauma, cardiac manipulation, reduced pulmonary function, effects of anesthetics and drugs, and autonomic nerve injury. Management involves identifying and treating the underlying causes, with electrical or pharmacological cardioversion used for more severe cases. Preventive measures include correcting electrolyte imbalances and using beta blockers to reduce the risk of atrial fibrillation.

1. JIMMA UNIVERSITY INSTITUTE
OF HEALTH SCIENCE,
DEPARTMENTS OF ANESTHESIA
Cardiac Arrhythmia After Thoracic surgery
Gemechis Akuma
April 2023

2. Learning objectives
• At the end of this presentation we will be able to:
Identify the common post-thoracotomy cardiac arrhythmias
Discuss the potential mechanisms and risk factors for these
rhythm disturbances post thoracotomy
Describe treatment option and prevention of post
thoracotomy arrhythmia
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3. Introduction
• Postoperative cardiac dysrhythmias are common after
thoracic surgery; open thoracotomy or VAT
• The most common arrhythmia is atrial fibrillation,
although other forms of supraventricular arrhythmias
(AF, AT), ventricular tachyarrhythmias (VT,VF), and
conduction disturbances (high-degree AV block can
also occur
• Supraventricular dysrhythmias occur in as many as
20% following thoracotomy. (Vretzakis et al., 2013)
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4. • Abnormalities of rate, regularity, site of impulse
origin, and sequence of activation are some
documented complications.
• These arrhythmias usually have an uneventful
clinical course and revert to normal sinus
rhythm, before patent’s discharge.
• In some case this may associated with
immediate hemodynamic consequences, longer
hospital stay and higher cost
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5. Factors contributing to these dysrhythmias:
• Underlying cardiac disease,
• Degree of surgical trauma
• Intraoperative cardiac manipulation
• A reduced pulmonary function
• Effects of anesthetics and cardio-active drugs
• Metabolic abnormalities
• Male gender and old age
• Direct injury /stimulation of the ANS by pain
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6. Pathophysiology
• It is complex and their clinical manifestation requires both
the presence of a vulnerable cardiac substrate and a trigger
factors
• Changes in myocardial structure and electrical function
constitute the substrate for arrhythmias
– atrial fibroses (favoring AT,AF/AFI), myocardial hypertrophy
(prolongation of repolarization), chamber dilatation (favoring for,
ectopic automaticity), or a post myocardial infarction scar
(promoting sustained VT).
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7. • The arrhythmia trigger is defined as a single
incident that may set off an arrhythmia
• Many perioperative factors can be affect both
the arrhythmia substrate and trigger
– Patient related and surgery related factors
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8. Patient-related risk factors
• Increasing age
• Men
• Hx of arrhythmias
• Structural heart disease (CAD, valve disease,
LV hypertrophy, LV dysfunction)
• Extracardiac risk factors (obesity, sleep apnea
syndrome, previous stroke, and concomitant
lung disease)
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9. Surgery-related risk factors
• Surgical trauma (type of procedure, magnitude of lung resection,
dissection near atria, mechanical factors such as instrumentation,
direct injury/stimulation of the ANS by pain
• Hemodynamic stress (volume overload or depletion, HTN,
endogenous catecholamines)
• Metabolic changes (hypoxemia, hypercarbia, acid–base imbalance
• Electrolyte disturbances (particularly hypokalemia)
• Drug effects (BB withdrawal, digoxin, exo/catecholamines, etc.)
• Anesthesia technique and drugs
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10. The heart is innervated by both SNS and PS
filaments, accompanying the coronary arteries and
their branches.
• Autonomic cardiac nerves may be exposed,
retracted, and injured during thoracic surgery.
• cardiac plexus located between the aortic arch and
the tracheal bifurcation
– vulnerable to direct damage, especially in thoracotomies
implicating dissection of pulmonary hilum or sampling of
nodes located in this area
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11. • Injury to the PS branches of the SA node may
result in increased heart rate and affect AV
conduction.
• Surgically induced alterations in the efferent
sympathetic outflow to the heart may account
for postop cardiac arrhythmias.
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13. Routine measure for all intraop
arrhythmia
• Assure adequate oxygenation and ventilation
• Alteration in depth of anesthesia
• Assume optimum O2,CO2, acid/base/, electrolyte,
temp.
• Reevaluate cardiac hx/pathology
• Get ready for
– ant arrhythmia drugs
– Anti-ischemic drugs
– Pacing and DC shock
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15. 1. Bradycardia after thoracic
surgery
• Bradyarrhythmia's are common after cardiac
surgery (particularly after valve surgery), but
are relatively rare after noncardiac thoracic
surgery
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17. Management
• In asymptomatic no t/t required
• For mildly symptomatic pt eliminate
underlined factors
• Atropine 0.5 mg iv may used??
• In severely symptomatic those with chest pain
/syncope immediate pacing required
• Epinephrine or dopamine
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19. 2. Sinus Tachycardia after thoracic
surgery
• Regular and 100-160 rate?
• Increased SA node discharge
• 20 to symphatatic stimulation/physiology,
patho, pharm response/
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22. 3. Paroxysmal Supraventricular
Tachycardia
• Postop PSVT is relatively rare, it may occur
from time to time.
• related symptoms include palpitations,
fatigue, chest discomfort, and dyspnea.
• are usually young (<60 years of age) and not
have structural heart disease.
• The arrhythmia has an abrupt onset, 160 - 220
beta/min.
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23. • The most common form of PSVT is AV-nodal
reentrant tachycardia.
– arrhythmia involves dual electrical pathways in or
near the AV node.
• The second most common form is AV- re-
entrant tachycardia involving an extranodal
accessory pathway
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24. • Vagal maneuvers (breath holding or the
Valsalva maneuver) are not always successful;
• Adenosine 6 mg can be used in increasing
doses.
• Success rates are exceed 95% and Electrical
cardioversion is rarely needed.
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25. 4. VENTRICULAR ARRYTHYMIA
• Postop Ventricular arrhythmia do not indicate an
increased risk for the development of malignant
ventricular tachyarrhythmias (i.e., sustained VT, Vf
and PVT)
• May not need for further evaluation or treatment.
• Reported incidences after surgery range from 0.5 to
1.5%
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26. • When frequent and complex premature beats and
nonsustained VT occur, the correction of any reversible
cause in mandatory.
• Antiarrhythmic drugs may be indicated when longer
and/or repeated ventricular tachycardia develop.
– amiodarone 150 mg over 10 minutes
– Class I antiarrhythmic drugs e.g., lidocaine or procaine amide
• PVT need immediate cardio version /defirlibration and
CPR.
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28. 5. Atrial fibrillation
• POAF is the most common periop cardiac
arrhythmia.
• Commonly occur within 2–4 days postop(12 to 44%)
• Advanced age is major risk both
Thoracic surgical procedures risk were divided based
on expected incidence of POAF
multiple effects on cardiopulmonary hemodynamics,
tachyarrhythmia is most common presentation.
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29.  rapid irregular rate cause insufficient coronary
flow to compensate myocardial O2 demand
Decreased diastolic filling time and CO
 increased risk of stroke, mortality, and LoS in hospital
 AF presents as a brady → lead to ↓ CO in fixed SV.
 loss of atrial contraction, mainly in patients with HT and
diastolic dysfunction, increases PA pressures
 These effect can lead to hypotension, HF, and MI.
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30. Periop management
• New onset AF before surgery postpon and correct
• T/t during sx depend on hemodynamic of stability
• If hemo-dynamicaly significant t/t cardio version
– Synchronized elect. cardio version 100-200J effective
– Pharm. Cardio version IV amiodarone (pref),
diltiazem, verapamil may used
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31. • Chronic AF maintain their antiarrhythmic
drugs and close follow electrolyte (K and Mg)
• Manage the transition on and off IV and oral
anticoagulant
correct reversible conditions like electrolytes
imbalances to prevent the POAF.
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32. • Immediate electrical cardioversion is indicated
in severe hemodynamic deterioration in
response to POAF.
– The administration of phenylephrine will support
cardiac output.
– impaired CO vs effect pulmonary function in
volume depletion.
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33. • Amiodarone IV should be preferred in patients
with known severe systolic dysfunction.
• CCB and digitalis to treat POAF
– Verapamil has been reported to be effective.
• hypotension from vasodilatory and negative inotropic.
• BB may be necessary for rapid supraventricular
dysrhythmias associated with HTN and MI, but
may cause bronchospasm.
– Esmolol is effective but short acting
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34. • Patients who develop atrial fibrillation after
surgery are at risk of thromboembolic events,
including stroke
– weighed against the risk of postoperative bleeding
and a reduction of thromboembolic event
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35. Prevention and treatment of postthoracotomy
arrhythmias is an important issue
Prophylactic metoprolol can decrease the
incidence of AF.
Prophylactic digitalization has long been
recommended, but recent studies have
reported either no difference or a higher
incidence of arrhythmias in thoracic surgical
patients receiving digoxin.
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36. 6. Atrial flutter
• relatively uncommon compared to atrial
fibrillation.
• It is sometimes confused with atrial
fibrillation.
• atrial flutter is more organized and less chaotic
than the abnormal pattern common with AF
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37. • The approach to patients with atrial flutter is
similar with the exception that class I
antiarrhythmic agents should not be used in
patients with atrial flutter.
• Electrical cardioversion is the preferred
method to achieve sinus rhythm
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40. 1. Class I: Sodium Channel Blockers: e.g.
– Class IA :procainamide,
– Class IB: lidocaine and phenytoin, and
– Class IC: flecainide.
2. Class II: Beta Blockers e.g. metoprolol,
propranolol, esmolol, atenolol, and timolol.
3. Class III: Potassium Channel Blockers e.g.
amiodarone
4. Class IV: Calcium Channel Blockers e.g. verapamil
and diltiazem
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45. References
1. Miller’s Anesthesia 9th edition volume 2
2. Morgan & Mikhail’s Clinical Anesthesiology 6th Edition
3. Factors associated with cardiac rhythm disturbances in the early post-pneumonectomy
period: Volume 23, Issue 3, March 2003, Pages 384–389
4. Haverkamp W, Hachenberg T. Post-thoracotomy dysrhythmia. Curr Opin Anaesthesiol.
2016
5. Vaporciyan AA, Correa AM, Rice DC, et al. Risk factors associated with atrial
fibrillation after noncardiac thoracic surgery: analysis of 2588 patients. J Thorac
Cardiovasc Surg 2004; 1
6. American Association for Thoracic Surgery. 2014 AATS guidelines for the prevention
and management of perioperative atrial fibrillation and flutter for thoracic surgical
procedures. J Thorac Cardiovasc.
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