Browse categories and answer follow-up questions to refine your symptom profile.
History
Presenting symptoms
Symptom characterization
Syncope or presyncope with implanted device
Palpitations or perceived arrhythmia
Dyspnea or exercise intolerance
Chest pain
ICD shock or vibration alert
Dizziness or near falls
Weakness or fatigue
Device pocket pain or swelling
Fever or rigors with device
Device history
Device details
Pacemaker
ICD
CRT pacemaker
CRT defibrillator
Implant date and indication
Recent generator change
Recent lead revision
Recent ablation or cardiac surgery
Manufacturer and model if known
OPQRST
Symptom timeline
Onset
Sudden onset
Gradual onset
Provocation and palliation
Exertion related
Position related
Vagal trigger
Relief with rest
Quality
Lightheadedness
Palpitations
Chest pressure
Dyspnea sensation
Region and radiation
Chest discomfort location
Radiation to jaw
Radiation to arm
Pocket discomfort location
Severity
Near syncope
Complete loss of consciousness
Multiple ICD shocks
Timing
Constant symptoms
Intermittent episodes
Clustered events
Associated symptoms
Associated symptoms
Diaphoresis
Nausea or vomiting
Neurologic deficit symptoms
Fever
Chills
Orthopnea
Pleuritic pain
Hemoptysis
Pocket drainage
ICD shock details
Shock event characterization
Single shock
Multiple shocks
Shocks at rest
Shocks with activity
Prodrome before shock
Loss of consciousness with shock
Chest pain after shock
Device audible alert history
Exposures and triggers
Trigger review
Recent strong electromagnetic exposure
TENS unit exposure
Electrocautery exposure
High voltage work exposure
MRI exposure
Recent falls or chest trauma
Alarm Features
Immediate threats
Life threat triggers
Hemodynamic instability
Ongoing chest pain with ischemic features
Ventricular tachycardia or ventricular fibrillation
Recurrent ICD shocks
Symptomatic bradycardia with hypoperfusion
Suspected cardiac tamponade
Suspected device infection with sepsis
Vital sign danger thresholds
Vital thresholds
Systolic blood pressure less than 90 mmHg with symptoms
Oxygen saturation less than 90 percent on room air
Heart rate less than 40 per minute with symptoms
Sustained heart rate greater than 150 per minute with symptoms
Temperature 38.0 C or higher with device pocket concerns
High risk exam findings
Exam red flags
Altered mental status
New focal neurologic deficit
Jugular venous distension with hypotension
New muffled heart sounds
Rapidly expanding pocket hematoma
Purulent pocket drainage
Crepitus at pocket
High risk device specific patterns
Device red flags
Electrical storm
Incessant ventricular arrhythmia despite therapy
Pacer dependency with suspected malfunction
Failure to capture with symptomatic bradycardia
Inappropriate shocks with distress
Escalation logic
Escalation
If unstable tachyarrhythmia, synchronized cardioversion
If pulseless, defibrillation and cardiac arrest algorithm
If suspected tamponade, immediate bedside ultrasound and cardiology involvement
If suspected device infection with sepsis physiology, early broad spectrum antibiotics and urgent specialty consultation
Medications
Home medications relevant to device presentations
Medication reconciliation
Beta blocker
Non dihydropyridine calcium channel blocker
Amiodarone
Sotalol
Dofetilide
Digoxin
Diuretic
ACE inhibitor or ARB
Sacubitril valsartan
SGLT2 inhibitor
Antithrombotics
Antithrombotic review
Aspirin
P2Y12 inhibitor
Warfarin
Direct oral anticoagulant
Recent missed doses
Recent supratherapeutic anticoagulation concern
Pro arrhythmic and interaction risks
QT and interaction risks
Recent QT prolonging antibiotics
Antipsychotic exposure
Antiemetic QT prolongation risk
Stimulant exposure
Thyroid medication dose change
ED medications with device context
ED medication safety
Adenosine caution in irregular wide complex tachycardia
AV nodal blockers caution in preexcited atrial fibrillation
Amiodarone infusion protocol dependent
Procainamide dosing protocol dependent
Diet
Intake patterns affecting arrhythmia and thresholds
Diet and hydration
Poor oral intake
Dehydration symptoms
High caffeine intake
Energy drink intake
High sodium intake in heart failure
Recent vomiting or diarrhea
Review of Systems
Cardiopulmonary
Cardiopulmonary symptoms
Exertional dyspnea
Orthopnea
Paroxysmal nocturnal dyspnea
Leg swelling
Chest pressure
Pleuritic pain
Palpitations
Infectious and inflammatory
Infectious symptoms
Fever
Chills
Night sweats
Unintentional weight loss
Pocket redness progression
Neurologic
Neurologic symptoms
Headache
Focal weakness
Speech difficulty
Seizure like activity
Post event confusion
Collateral History and Family History
Collateral sources
Collateral
Witness description of syncope
EMS rhythm strips if available
Device clinic notes if available
Prior device interrogation reports
Family history
Family history
Sudden cardiac death
Cardiomyopathy
Channelopathy
Early coronary artery disease
Social reliability
Support and follow up reliability
Ability to attend urgent device clinic follow up
Medication access
Home monitoring presence
Risk Factors
Device and procedure risks
Device related risks
Recent implantation less than 6 weeks
Recent generator change
Multiple prior leads
Prior device infection
Pacer dependent status
Known lead recall or advisory
Arrhythmia and cardiac risks
Cardiac risks
Ischemic cardiomyopathy
Non ischemic cardiomyopathy
Prior ventricular tachycardia
Prior atrial fibrillation
Heart failure reduced ejection fraction
Structural heart disease
Infection and bleeding risks
Infection and bleeding risks
Diabetes mellitus (E11.9)
Chronic kidney disease (N18.9)
Immunosuppression
Anticoagulation
Antiplatelet therapy
Hematoma after implant history
Exposure risks
Electromagnetic and toxin risks
Stimulant use
Cocaine or sympathomimetic exposure
Carbon monoxide exposure possibility
Significant electromagnetic interference exposure
Differential Diagnosis
Life threatening
Life threatening causes
Ventricular tachycardia (I47.2)
Shock syncope correlation
Wide complex tachycardia on ECG
Ventricular fibrillation (I49.01)
Cardiac arrest history
Multiple ICD therapies
Acute coronary syndrome (I21.9)
New ischemic ECG changes
Rising troponin pattern
Pacemaker failure in pacer dependent patient (T82.110A)
Failure to capture on ECG
Profound bradycardia
Cardiac tamponade from lead perforation (I31.4)
Hypotension with jugular venous distension
Pericardial effusion on ultrasound
Pulmonary embolism (I26.99)
Hypoxia with tachycardia
Pleuritic pain or hemoptysis
CIED infection with bacteremia or endocarditis (T82.7XXA)
Fever with pocket changes
Positive blood cultures
Common
Common causes
Inappropriate ICD shock from supraventricular tachycardia
Narrow complex tachycardia history
Shock during exertion with palpitations
Atrial fibrillation with rapid ventricular response (I48.91)
Irregularly irregular rhythm
Rate related symptoms
Lead fracture or insulation failure (T82.110A)
Intermittent sensing abnormalities
Noise on interrogation history
Pacemaker mediated tachycardia
Regular tachycardia near upper tracking rate
Retrograde P waves pattern on ECG
Battery depletion elective replacement indicator
Change in pacing mode
New bradycardia or fatigue
Vasovagal syncope (R55)
Typical prodrome
Normal device function on interrogation
Less common
Less common causes
Twiddler syndrome with lead displacement (T82.120A)
Pocket manipulation history
Change in lead position on chest radiograph
Oversensing from electromagnetic interference
Symptom timing near exposure
Inhibition of pacing on ECG pattern
Myocarditis (I40.9)
Viral prodrome
Troponin elevation with non ischemic ECG
Electrolyte mediated arrhythmia
Hypokalemia
Hypomagnesemia
Mimics and non cardiac
Mimics
Seizure
Tongue bite history
Post event confusion
Orthostatic hypotension
Volume depletion history
Postural symptom pattern
Anxiety or panic
Normal rhythm during symptoms
Reassuring cardiopulmonary evaluation
Past Medical History
Cardiac history
Cardiac history
Indication for device
Prior myocardial infarction
Prior revascularization
Heart failure stage and baseline symptoms
Prior arrhythmia ablation
Baseline ejection fraction
Device and procedural history
Device history
Prior lead extraction
Prior pocket revision
Prior device infection
Device advisory or recall history
Other relevant history
Comorbidities
Chronic kidney disease
Diabetes mellitus
COPD
Obstructive sleep apnea
Thyroid disease
Physical Exam
General and hemodynamics
General assessment
Toxic appearance
Perfusion assessment
Mental status
Volume status
Cardiovascular
Cardiovascular exam
Rate and rhythm assessment
Murmur new or changed
Jugular venous distension
Peripheral edema
Signs of tamponade physiology
Respiratory
Respiratory exam
Work of breathing
Crackles
Wheeze
Asymmetric breath sounds
Device pocket and leads
Pocket exam
Erythema
Warmth
Fluctuance
Drainage
Skin erosion
Tenderness
Hematoma size and tension
Neurologic and trauma
Neuro and trauma screen
Focal neurologic deficit
Postictal features
Head or facial trauma from syncope
Cervical spine pain after fall
Special populations considerations
Special populations exam
Pregnancy uterine size considerations for imaging decisions
Pediatric device location and growth related lead strain
Anticoagulated patient bruising and pocket bleeding
Lab Studies
Core ED labs
Baseline labs
CBC for anemia and leukocytosis
Electrolytes including potassium
Magnesium level
Creatinine and renal function
Glucose
Cardiac and ischemia evaluation
Cardiac labs
Troponin trend when ischemia concern
BNP or NT proBNP when heart failure concern
Infection evaluation
Infection labs
Blood cultures times two if fever or pocket infection concern
Lactate when sepsis physiology
CRP or ESR as supportive data when unclear
Toxicology and endocrine
Additional labs
TSH when new arrhythmia or amiodarone exposure concern
Toxicology testing when stimulant exposure concern
Lab interpretation pitfalls
Pitfalls
Mild troponin elevation after ICD shocks possible
Electrolyte abnormalities can trigger shocks and arrhythmias
Fever absent in early device infection
Imaging
Scoring Systems
Decision tools
Syncope risk stratification tool local protocol dependent
Pulmonary embolism pretest probability tool when PE concern
Sepsis screening criteria for infection physiology
MRI
MRI considerations
MRI conditional device status required before MRI
Device and lead compatibility required
Coordination with device team for mode programming
Non conditional system treated as high risk without specialist protocol
CT
CT considerations
CT pulmonary angiography when PE concern and appropriate renal function
CT head when syncope with head trauma or focal neurologic findings
Contrast nephropathy risk in CKD
Radiation consideration in pregnancy and pediatrics
Ultrasound
Ultrasound and POCUS
Bedside echocardiography for pericardial effusion
Lung ultrasound for pulmonary edema
IVC assessment as adjunct to volume status
Venous ultrasound for DVT when PE pathway considered
Special Tests
Device interrogation and related diagnostics
Device evaluation
Urgent device interrogation for shocks or suspected malfunction
Review of stored electrograms if available
Battery status including elective replacement indicator
Lead parameters sensing impedance thresholds
Chest radiograph evaluation
Chest radiograph
Lead position assessment compared with prior
Lead fracture clues
Generator position and rotation clues
Magnet response testing
Magnet use
Magnet effect differs by manufacturer and programming
Pacemaker magnet typically asynchronous pacing while applied
ICD magnet typically disables tachy therapies while applied
Use only with monitoring and specialist input when feasible
Bedside maneuvers and monitoring
Bedside diagnostics
Orthostatic vitals when appropriate
Continuous telemetry for suspected arrhythmia
Serial neurologic checks after syncope related trauma
ECG
Immediate ECG priorities
ECG triage
12 lead ECG early for syncope or shock presentation
Rhythm strip and telemetry correlation with symptoms
Paced rhythm interpretation
Paced ECG interpretation
Atrial paced spikes with P wave capture
Ventricular paced spikes with wide QRS morphology
Biventricular pacing pattern for CRT
Pacing rate compared with programmed lower rate if known
Malfunction patterns
Malfunction ECG patterns
Failure to pace with absent pacing spikes when expected
Failure to capture with spikes not followed by depolarization
Undersensing with inappropriate pacing spikes
Oversensing with inappropriate inhibition of pacing
Tachyarrhythmia patterns relevant to devices
Tachyarrhythmias
Monomorphic wide complex tachycardia treated as ventricular tachycardia until proven otherwise
Polymorphic wide complex tachycardia with QT prolongation concern
Atrial fibrillation with rapid ventricular response
Supraventricular tachycardia triggers for inappropriate ICD therapy
High risk ECG findings
ECG red flags
Ischemic ST elevation or depression
New high grade AV block
Hyperkalemia ECG features
Brugada pattern concern
Preexcited atrial fibrillation concern
Assessment
Problem representation
Working problem list
ICD shock presentation with stability assessment
Syncope in patient with pacemaker or ICD
Suspected pacemaker malfunction
Suspected device pocket infection
Suspected lead complication after recent implant
Severity stratification
Severity stratification
Unstable physiology requiring resuscitation bay
Electrical storm suspicion with recurrent therapies
Pacer dependent risk with suspected capture failure
Sepsis physiology with device infection concern
Key complications to rule out
Complication screen
Acute coronary syndrome
Heart failure decompensation
Pulmonary embolism
Pericardial effusion and tamponade
Stroke or TIA after syncope or arrhythmia
Diagnostic uncertainty handling
Uncertainty
If symptoms but normal ECG and stable, prioritize device interrogation and ambulatory rhythm correlation
If pocket findings equivocal, prioritize blood cultures and specialist input
If intermittent symptoms, prioritize telemetry observation pathway when risk factors present
Plan
First minutes stabilization
Initial stabilization
Cardiac monitor and defibrillator pads for shock presentations
IV access and basic labs
Oxygen for hypoxia
Treat unstable arrhythmia per ACLS algorithms
ICD shock management
ICD shock plan
If unstable ventricular tachycardia, synchronized cardioversion
If ventricular fibrillation or pulseless ventricular tachycardia, defibrillation
If electrical storm with stability, antiarrhythmic infusion protocol dependent
If recurrent shocks with distress and suspected inappropriate therapy, consider magnet to suspend tachy therapies with continuous monitoring and urgent cardiology involvement
Pacemaker malfunction management
Pacemaker malfunction plan
If symptomatic bradycardia with capture failure, transcutaneous pacing and escalation
If pacer dependent and suspected malfunction, urgent device interrogation and cardiology
Correct reversible causes including electrolytes and ischemia
Avoid external electrical interference sources when identified
Pocket hematoma and bleeding
Pocket bleeding plan
Analgesia and local measures
Anticoagulation management local protocol dependent
Pacer dependency with any suspicion of malfunction
Suspected device infection
Syncope with high risk ECG findings
Observation pathway criteria
Observation criteria
Stable single shock with unclear appropriateness pending interrogation
Stable palpitations with device and need for telemetry correlation
Syncope with intermediate risk features and planned urgent interrogation
Discharge criteria
Discharge criteria
Stable vitals with reassuring evaluation
Device interrogation reassuring with clear explanation of symptoms
No concerning pocket findings
Reliable rapid follow up with device clinic
Follow up timing
Follow up plan
Device clinic follow up within 24 to 72 hours for recent shock or alerts
Cardiology follow up within 1 week for medication changes
Primary care follow up for contributing factors
Discharge Instructions
Copy discharge instructions
Discharge text
You were evaluated for symptoms in the setting of an implanted cardiac device
Return immediately for fainting, chest pain, trouble breathing, repeated shocks, fever, or worsening pocket redness or drainage
Avoid strong electromagnetic sources near your device and keep phones and magnets away from the implant site
Take your medications as prescribed and do not stop heart rhythm medicines without medical advice
Arrange urgent follow up with your device clinic as directed
If you received an ICD shock today, do not drive until cleared by your clinician local protocol dependent
References
Guidelines and key sources
Reference list
AHA Guidelines for CPR and ECC 2020
ESC Guidelines on cardiac pacing and cardiac resynchronization therapy 2021
HRS Expert Consensus Statement on cardiovascular implantable electronic device lead management and extraction 2017
MADIT II trial 2002
SCD HeFT trial 2005
Project instructions
SymptomDx is an educational tool for medical professionals. It does not replace clinical judgment. Verify all clinical data and drug dosages with authoritative sources.