All EMS presentations
CardiacClinical presentation

Pacemaker / ICD concern

A streamlined, differential-led presentation for rapid clinical review.

Clinical snapshot

Twenty-second review

  • Pacemakers and ICDs sense and treat rhythm disturbances, but lead failure, battery depletion, inappropriate therapy, infection, or underlying arrhythmia can cause symptoms.
  • Syncope, shock, repeated ICD shocks, failure to capture with poor perfusion, chest pain, or device-pocket infection with systemic illness is high risk.
  • Keep musculoskeletal or anxiety symptoms in the differential; overlapping or concurrent illness remains possible.
  • For pacemaker / icd concern, trends and combinations of findings are more informative than one isolated vital sign.
Differentials

Compare the clinical patterns

The repeated material is grouped inside each possibility. Open only the condition you need.

Serious3 conditions
Failure to captureTime-sensitive high-risk possibility

HPI

Clarify device type and indication; shock, alarm or suspected malfunction; symptoms before and after event.

Signs & symptoms

Poor perfusion, discordant pulse, recurrent shocks, or fever.

Focused exam

Assess pulse rate, regularity, strength, skin perfusion, JVP, edema, and lung sounds; Compare current function and exercise tolerance with baseline.

Brief pathophysiology

Failure to capture may cause pacemaker / icd concern through a time-sensitive process capable of rapid physiological deterioration.

Vital-sign pattern

What the trend may show

Possible pattern

There is no single diagnostic vital-sign pattern for this cardiac differential. Rate/rhythm, pressure, perfusion, and oxygenation are the four most useful serial observations.

Heart rate (bpm)

Assess rate / rhythm

Relate rate and rhythm to symptoms, ECG findings, and perfusion.

Blood pressure (mmHg)

Trend pressure

Both hypertension and hypotension can alter risk and management.

MAP (mmHg)

Trend perfusion

Interpret MAP with mentation, skin signs, and baseline pressure.

Oxygen saturation (SpO₂)

Usually preserved

Low saturation suggests heart failure or concurrent respiratory disease.

Front-load in the triage report

  • Failure to capture: Poor perfusion, discordant pulse, recurrent shocks, or fever.
  • Device type and indication?
  • Shock, alarm or suspected malfunction?
Malignant rhythmTime-sensitive high-risk possibility

HPI

Clarify shock, alarm or suspected malfunction; symptoms before and after event; rate, rhythm and 12-lead.

Signs & symptoms

Poor perfusion, discordant pulse, recurrent shocks, or fever.

Focused exam

Compare current function and exercise tolerance with baseline; Inspect the device pocket, compare pulse with rhythm and pacing spikes, obtain 12-lead, and assess shocks, device card, and symptoms.

Brief pathophysiology

Malignant rhythm may cause pacemaker / icd concern through a time-sensitive process capable of rapid physiological deterioration.

Vital-sign pattern

What the trend may show

Possible pattern

There is no single diagnostic vital-sign pattern for this cardiac differential. Rate/rhythm, pressure, perfusion, and oxygenation are the four most useful serial observations.

Heart rate (bpm)

Assess rate / rhythm

Relate rate and rhythm to symptoms, ECG findings, and perfusion.

Blood pressure (mmHg)

Trend pressure

Both hypertension and hypotension can alter risk and management.

MAP (mmHg)

Trend perfusion

Interpret MAP with mentation, skin signs, and baseline pressure.

Oxygen saturation (SpO₂)

Usually preserved

Low saturation suggests heart failure or concurrent respiratory disease.

Front-load in the triage report

  • Malignant rhythm: Poor perfusion, discordant pulse, recurrent shocks, or fever.
  • Shock, alarm or suspected malfunction?
  • Symptoms before and after event?
Device infectionTime-sensitive high-risk possibility

HPI

Clarify symptoms before and after event; rate, rhythm and 12-lead; syncope, chest pain or dyspnea.

Signs & symptoms

Poor perfusion, discordant pulse, recurrent shocks, or fever.

Focused exam

Compare current function and exercise tolerance with baseline; Inspect the device pocket, compare pulse with rhythm and pacing spikes, obtain 12-lead, and assess shocks, device card, and symptoms.

Brief pathophysiology

Device infection may cause pacemaker / icd concern through a time-sensitive process capable of rapid physiological deterioration.

Vital-sign pattern

What the trend may show

Possible pattern

There is no single diagnostic vital-sign pattern for this cardiac differential. Rate/rhythm, pressure, perfusion, and oxygenation are the four most useful serial observations.

Heart rate (bpm)

Assess rate / rhythm

Relate rate and rhythm to symptoms, ECG findings, and perfusion.

Blood pressure (mmHg)

Trend pressure

Both hypertension and hypotension can alter risk and management.

MAP (mmHg)

Trend perfusion

Interpret MAP with mentation, skin signs, and baseline pressure.

Oxygen saturation (SpO₂)

Usually preserved

Low saturation suggests heart failure or concurrent respiratory disease.

Front-load in the triage report

  • Device infection: Poor perfusion, discordant pulse, recurrent shocks, or fever.
  • Symptoms before and after event?
  • Rate, rhythm and 12-lead?
Common2 conditions
Appropriate device therapyCommon presentation pattern

HPI

Clarify device type and indication; shock, alarm or suspected malfunction; symptoms before and after event.

Signs & symptoms

A shock may have terminated a real tachyarrhythmia even if symptoms resolve.

Focused exam

Assess pulse rate, regularity, strength, skin perfusion, JVP, edema, and lung sounds; Compare current function and exercise tolerance with baseline.

Brief pathophysiology

Appropriate device therapy may explain the presenting symptoms through a common clinical mechanism, while serial assessment checks for complications or an alternate cause.

Vital-sign pattern

What the trend may show

Possible pattern

There is no single diagnostic vital-sign pattern for this cardiac differential. Rate/rhythm, pressure, perfusion, and oxygenation are the four most useful serial observations.

Heart rate (bpm)

Assess rate / rhythm

Relate rate and rhythm to symptoms, ECG findings, and perfusion.

Blood pressure (mmHg)

Trend pressure

Both hypertension and hypotension can alter risk and management.

MAP (mmHg)

Trend perfusion

Interpret MAP with mentation, skin signs, and baseline pressure.

Oxygen saturation (SpO₂)

Usually preserved

Low saturation suggests heart failure or concurrent respiratory disease.

Front-load in the triage report

  • A shock may have terminated a real tachyarrhythmia even if symptoms resolve.
  • Device type and indication?
  • Shock, alarm or suspected malfunction?
Benign awarenessCommon presentation pattern

HPI

Clarify shock, alarm or suspected malfunction; symptoms before and after event; rate, rhythm and 12-lead.

Signs & symptoms

A shock may have terminated a real tachyarrhythmia even if symptoms resolve.

Focused exam

Compare current function and exercise tolerance with baseline; Inspect the device pocket, compare pulse with rhythm and pacing spikes, obtain 12-lead, and assess shocks, device card, and symptoms.

Brief pathophysiology

Benign awareness may explain the presenting symptoms through a common clinical mechanism, while serial assessment checks for complications or an alternate cause.

Vital-sign pattern

What the trend may show

Possible pattern

There is no single diagnostic vital-sign pattern for this cardiac differential. Rate/rhythm, pressure, perfusion, and oxygenation are the four most useful serial observations.

Heart rate (bpm)

Assess rate / rhythm

Relate rate and rhythm to symptoms, ECG findings, and perfusion.

Blood pressure (mmHg)

Trend pressure

Both hypertension and hypotension can alter risk and management.

MAP (mmHg)

Trend perfusion

Interpret MAP with mentation, skin signs, and baseline pressure.

Oxygen saturation (SpO₂)

Usually preserved

Low saturation suggests heart failure or concurrent respiratory disease.

Front-load in the triage report

  • A shock may have terminated a real tachyarrhythmia even if symptoms resolve.
  • Shock, alarm or suspected malfunction?
  • Symptoms before and after event?
Mimics2 conditions
MusculoskeletalImportant alternative presentation

HPI

Clarify device type and indication; shock, alarm or suspected malfunction; symptoms before and after event.

Signs & symptoms

Device-area discomfort may be unrelated but requires rhythm assessment.

Focused exam

Assess pulse rate, regularity, strength, skin perfusion, JVP, edema, and lung sounds; Compare current function and exercise tolerance with baseline.

Brief pathophysiology

Musculoskeletal can resemble pacemaker / icd concern through overlapping symptoms or referred physiology despite a different primary mechanism.

Vital-sign pattern

What the trend may show

Possible pattern

Isolated musculoskeletal injury often leaves central vital signs near baseline. Persistent abnormality should prompt reassessment for hemorrhage, thoracic injury, infection, or a medical cause.

Heart rate (bpm)

May rise with pain

Tachycardia can reflect pain or distress; trend after treatment.

Blood pressure (mmHg)

May rise with pain

Hypotension is not expected in an isolated minor injury.

Respiratory rate (breaths/min)

May rise with pain

Persistent tachypnea suggests more than a minor isolated injury.

Oxygen saturation (SpO₂)

Usually preserved

Desaturation suggests thoracic injury or concurrent disease.

Front-load in the triage report

  • Device-area discomfort may be unrelated but requires rhythm assessment.
  • Device type and indication?
  • Shock, alarm or suspected malfunction?
Anxiety symptomsImportant alternative presentation

HPI

Clarify shock, alarm or suspected malfunction; symptoms before and after event; rate, rhythm and 12-lead.

Signs & symptoms

Device-area discomfort may be unrelated but requires rhythm assessment.

Focused exam

Compare current function and exercise tolerance with baseline; Inspect the device pocket, compare pulse with rhythm and pacing spikes, obtain 12-lead, and assess shocks, device card, and symptoms.

Brief pathophysiology

Anxiety symptoms can resemble pacemaker / icd concern through overlapping symptoms or referred physiology despite a different primary mechanism.

Vital-sign pattern

What the trend may show

Possible pattern

There is no single diagnostic vital-sign pattern for this cardiac differential. Rate/rhythm, pressure, perfusion, and oxygenation are the four most useful serial observations.

Heart rate (bpm)

Assess rate / rhythm

Relate rate and rhythm to symptoms, ECG findings, and perfusion.

Blood pressure (mmHg)

Trend pressure

Both hypertension and hypotension can alter risk and management.

MAP (mmHg)

Trend perfusion

Interpret MAP with mentation, skin signs, and baseline pressure.

Oxygen saturation (SpO₂)

Usually preserved

Low saturation suggests heart failure or concurrent respiratory disease.

Front-load in the triage report

  • Device-area discomfort may be unrelated but requires rhythm assessment.
  • Shock, alarm or suspected malfunction?
  • Symptoms before and after event?
Red flags

Findings that should escalate concern

  • Syncope
  • Repeated ICD shocks
  • Unstable rhythm
  • Chest pain
  • Syncope, shock, repeated ICD shocks, failure to capture with poor perfusion, chest pain, or device-pocket infection with systemic illness is high risk.
  • Failure to capture, malignant rhythm, or device infection: Poor perfusion, discordant pulse, recurrent shocks, or fever.
Related medications

Medication recognition

AmoxicillinMetoprololDiltiazemCephalexinDigoxinAmiodarone
Related EMS presentations

Continue the clinical pathway

CardiacChest pain / suspected ACSCardiacSyncope / presyncopeCardiacPalpitations / tachyarrhythmiaCardiacCHF / acute pulmonary edemaCardiacBradycardia
References

Clinical and academic sources

Curated clinical guidance and peer-reviewed evidence supporting this presentation. Current BCEHS guidance, medical direction, and local policy remain authoritative for practice.

BCEHS Handbook — specific CPGs

  1. C02: BradycardiaBC Emergency Health Services Handbook

    Official BCEHS clinical practice guidance for bradycardia.

  2. N01: Peri-Arrest ManagementBC Emergency Health Services Handbook

    Official BCEHS clinical practice guidance for peri-arrest management.

Supporting clinical and academic evidence

  1. Guideline for the Management of Patients With Acute Coronary SyndromesACC/AHA/ACEP/NAEMSP/SCAI

    2025 evidence-based acute coronary syndrome recognition and management guidance.

  2. CEDIS Presenting Complaint List updateCanadian Association of Emergency Physicians

    Presenting-complaint terminology and categorization context. It does not establish a prehospital “top 100” ranking.

  3. Transvenous Pacemaker Placement: A Review for Emergency CliniciansJournal of Emergency Medicine · 2024

    Pacing indications, capture and sensing, complications, and emergency assessment of pacing failure.