🔹 Case 1 – “My heart just started racing out of nowhere.”
Age / Gender: 24-year-old female
Chief Complaint: Sudden onset of palpitations
Vitals: T 36.7°C, HR 168, BP 110/70, RR 18, SpO₂ 98%
EKG findings
HR 168/min reg, PR interval 0.15s, QTc 420ms, normal QRS complex, no ST/T change
Structured History
- Opening: “I don’t know… My heart just started racing all of a sudden.”
- Shoreline: “It’s been happening on and off for a few months, but today it felt much stronger and longer than usual, so I came in.”
- Onset & Course: Sudden, while sitting; lasted 15–20 minutes
- Associated Symptoms: Lightheadedness, sweating, no chest pain
- PMH / Meds: Healthy, no meds except ibuprofen for cramps
- PAM HITS FOSS: No medical history, college student, mild stress, occasional alcohol, sexually active
- Concerns: “Is this dangerous?” “Is it from stress or caffeine?”
Physical Examination
- Alert, no acute distress
- Lungs clear; Heart tachycardic, regular rhythm, no murmur
- No JVD, no edema, neuro intact
Differential Diagnosis
- PSVT (AVNRT) – abrupt, young female, healthy
- Inappropriate sinus tachycardia – stress-related but less likely
- Panic attack – no emotional trigger, very high HR
Clinical Reflection
“Classic paroxysmal SVT. We’ll confirm with ECG and consider vagal maneuvers or Holter.”
Clinical Pearls
- SVT = sudden onset/offset
- Often benign in young women
- Try vagal maneuvers before meds
Challenging Questions
Q: “Could this be fatal?”
A: “It’s rarely dangerous, but it’s uncomfortable. We’ll monitor your heart and run tests to be safe.”
SOAP Note
S: 24F with sudden palpitations, self-resolving. No CP or syncope. HR 168 at time of episode. O: T 36.7, BP 110/70, HR 168. Lungs clear, heart tachycardic, regular. A: # Palpitations – paroxysmal # Likely PSVT # No underlying heart disease P: - ECG and labs (CBC, TSH, electrolytes) - Vagal maneuvers education - Holter monitor if needed - F/U in 1–2 weeks
🔹 Case 2 – “Sometimes I feel this strange sensation in my chest…”
Age / Gender: 54-year-old male
Chief Complaint: Chest discomfort and dizziness
Vitals: T 36.5°C, HR 42, BP 100/64, RR 16, SpO₂ 97%
EKG findings
HR 42/min reg, PR interval 0.18s, QTc 420ms, normal QRS complex, no ST/T change
Structured History
- Opening: “I’ve been feeling this weird sensation in my chest… and sometimes I get lightheaded.”
- Shoreline: “Started weeks ago, more frequent now.”
- Associated Symptoms: Dizziness, fatigue, near-fainting
- PMH / Meds: Hypertension; started metoprolol 3 months ago
- PAM HITS FOSS: Retired accountant, no smoking, father had pacemaker
- Concerns: “Is this from my meds?” “Will I need a pacemaker?”
Physical Examination
- Bradycardic (HR 42), regular
- Lungs clear, heart sounds normal
- No focal neuro signs, gait steady
Differential Diagnosis
- Beta-blocker–induced bradycardia
- Sick sinus syndrome
- Hypothyroidism
Clinical Reflection
“He’s bradycardic with fatigue—probably metoprolol-related, but I won’t ignore intrinsic sinus disease.”
Clinical Pearls
- Older adults with bradycardia = always check meds
- Fatigue + dizziness may be SND
- TSH is always part of bradycardia workup
Challenging Questions
Q: “Do I need a pacemaker like my dad?”
A: “Possibly, but we’ll start with tests. It could be just the medication. Let’s figure it out together.”
SOAP Note
S: 54M with dizziness and fatigue. HR 42, started metoprolol 3 months ago. O: T 36.5, BP 100/64. Bradycardia, lungs clear. A: # Bradycardia # On beta-blocker # R/O SND, hypothyroidism P: - ECG, labs (TSH, electrolytes) - Hold beta-blocker - Monitor HR - Holter monitor - Cardiology referral
🔺 Case 3 – “My chest feels like it’s about to explode when I stand up.”
Age / Gender: 32-year-old female
Chief Complaint: Palpitations and dizziness upon standing
Vitals: HR 72 supine → 122 standing, BP 112/68, RR 16, SpO₂ 98%
EKG findings
HR 72/min reg supine, HR 122/min reg standing, PR interval 0.16s, QTc 420ms, normal QRS complex, no ST/T change
Structured History
- Opening: “Every time I stand up, my heart starts racing and I feel like I’m going to pass out.”
- Shoreline: “It’s been going on for months. My heart pounds when I stand.”
- Associated Symptoms: Dizziness, fatigue, blurred vision, no true syncope
- PMH / Meds: None; only takes vitamins
- PAM HITS FOSS: Remote worker, inactive, mother has fibromyalgia
Physical Examination
- Standing HR jumps by >30 bpm
- No JVD, lungs clear, heart regular
- Cool extremities, mild leg mottling
Differential Diagnosis
- POTS
- Anxiety disorder
- Hyperthyroidism
Clinical Reflection
“HR spikes on standing, chronic fatigue, and no hypotension – classic for POTS. Easy to miss if you don’t check vitals upright.”
Clinical Pearls
- POTS ≠ orthostatic hypotension
- Fatigue may dominate over palpitations
- Standing HR rise >30 bpm in adults = diagnostic clue
SOAP Note
S: 32F with palpitations, dizziness when standing. No CP or syncope. O: HR 72 → 122 standing. BP stable. EKG: PR 0.16s, QTc 420ms. A: # Orthostatic palpitations # Suspected POTS P: - Orthostatic vitals - TSH, electrolytes - Fluids, salt loading - Holter / tilt-table test
🔺 Case 4 – “I fainted after skipping a few meals…”
Age / Gender: 61-year-old female
Chief Complaint: Syncope after poor intake
Vitals: HR 56, BP 98/60, RR 18, SpO₂ 97%
EKG findings
HR 56/min reg, PR interval 0.18s, QTc 480ms, normal QRS complex, no ST/T change
Structured History
- Opening: “I passed out in my kitchen this morning.”
- Shoreline: “I hadn’t eaten much. Felt woozy, then blacked out.”
- Associated Symptoms: Nausea, poor appetite, palpitations before fainting
- PMH / Meds: Hypertension, takes HCTZ and ibuprofen
- PAM HITS FOSS: Lives alone, retired teacher
Physical Examination
- Dry mucosa, pale, bradycardic
- Heart regular, no murmurs
- Neuro intact
Differential Diagnosis
- QT prolongation due to electrolyte disturbance
- Drug-induced bradyarrhythmia
- Sick sinus syndrome
Clinical Reflection
“QTc 480ms + diuretic + low intake = high TdP risk. Need to act fast on K and Mg.”
SOAP Note
S: 61F with syncope. Poor appetite. On HCTZ. Palpitations before faint. O: HR 56, QTc 480ms. Dry mucosa, neuro intact. A: # QT prolongation # Suspected electrolyte imbalance (hypoK, hypoMg) P: - IV potassium and magnesium - Monitor telemetry - Labs: BMP, Mg, Ca - Hold QT-prolonging drugs
📌 Summary & Clinical Tips
- Case 1: PSVT – classic paroxysmal rhythm in young women
- Case 2: Bradycardia from β-blocker, possible SND
- Case 3: POTS – sustained HR rise without hypotension
- Case 4: QT prolongation from HCTZ + poor intake
🧠 Pearls
- Don’t forget standing vitals – they’re essential
- QTc > 480ms in elderly = emergency until proven otherwise
- Medication review is critical in bradycardia and syncope
📖 Glossary
- QTc: Corrected QT interval
- PSVT: Paroxysmal supraventricular tachycardia
- SND: Sick sinus syndrome
- POTS: Postural orthostatic tachycardia syndrome
📎 Related Articles
- Approach to Palpitaion: Palpitations: A Symptom-Based Clinical Approach
- 動悸の診かた：動悸（Palpitations）の診かた｜それって心原性？
- 🏠Mock patient home: 🩺 Mock Patient Scripts
📚 References
- Uptodate: Evaluation of palpitations in adults
- ESC Guidelines for Syncope (2022)
- ACC/AHA/HRS Guidelines for Bradyarrhythmias
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