What is the best course of action for a patient with a history of totally resolved angina (coronary artery disease) of 11 years duration, now experiencing intermittent palpitations (premature heartbeats) after lying down?

Management of Palpitations After Lying Down in a Patient with Resolved Coronary Artery Disease

This patient requires urgent cardiac evaluation with 12-lead ECG and ambulatory monitoring to rule out arrhythmias, as palpitations in someone with known coronary disease—even if previously resolved—may signal recurrent ischemia, coronary vasospasm, or life-threatening ventricular arrhythmias.

Immediate Assessment

Obtain a 12-lead ECG immediately to identify any acute ischemic changes, arrhythmias, or conduction abnormalities that could explain the palpitations 1, 2. The physical examination contributes little to diagnosing cardiac ischemia unless shock is present, but you should specifically assess for:

• Hemodynamic stability: Blood pressure, heart rate, and signs of heart failure 3
• Cardiac auscultation: Listen for new murmurs (mitral regurgitation can occur during ischemia), third or fourth heart sounds 4
• Signs of thyroid disease: Hyperthyroidism can cause palpitations 1

Risk Stratification for This Patient

The history of coronary artery disease places this patient at higher risk, even though the angina resolved 11 years ago 4. Key red flags to assess include:

• Timing and character: Palpitations occurring at rest (especially after lying down) raise concern for coronary vasospasm, which classically occurs at night or early morning 4, 5
• Associated symptoms: Dizziness, near-syncope, syncope, chest pain, or dyspnea indicate potentially serious arrhythmias requiring immediate intervention 1, 2
• Recurrent ischemia: Prior coronary disease increases the likelihood that palpitations represent ventricular arrhythmias triggered by ischemia 3

Diagnostic Approach

If the Initial ECG is Normal

Ambulatory ECG monitoring is indicated when the etiology cannot be determined from history, physical examination, and resting ECG 1. The choice of monitoring depends on symptom frequency:

• For unpredictable or non-daily palpitations: Use a two-week continuous closed-loop event recorder as the initial strategy 1
• For daily palpitations: 24-48 hour Holter monitoring may be appropriate 1, 2
• Trans-telephonic event monitors are more effective and cost-effective than Holter monitors for most patients 1

Consider Coronary Vasospasm

Palpitations occurring after lying down in a patient with prior coronary disease should raise suspicion for variant (Prinzmetal's) angina, which can present with:

• Nocturnal or rest angina with ST-segment elevations 4, 5
• Ventricular arrhythmias (extrasystoles or tachycardia) triggered by coronary spasm 5
• Normal exercise ECG but positive 24-hour Holter monitoring showing ST changes and arrhythmias 5

If coronary spasm cannot be ruled out and no ECGs during symptoms are available, coronary angiography with provocative testing (acetylcholine, adenosine, or methacholine) may be considered 4.

Treatment Strategy

If Arrhythmias Are Documented

Treatment depends on the specific arrhythmia identified:

• Benign premature ventricular contractions: May not require treatment if asymptomatic and structurally normal heart 1
• Ventricular tachycardia or high-risk arrhythmias: Require urgent cardiology referral and consideration of implantable cardioverter-defibrillator 4
• Supraventricular arrhythmias: Treat according to specific type (e.g., atrial fibrillation, atrial flutter) 1

If Coronary Vasospasm Is Confirmed

Coronary spasm is usually very responsive to first-line therapy 4:

• Calcium channel blockers in moderate to high doses: verapamil 240-480 mg/day, diltiazem 180-360 mg/day, or nifedipine 60-120 mg/day 4
• Long-acting nitrates in combination with calcium channel blockers for very active disease 4
• Avoid beta-blockers, as they have theoretical adverse potential in vasospastic angina (though clinical effect is controversial) 4
• Smoking cessation is mandatory 4

Optimize Secondary Prevention

Regardless of the cause of palpitations, this patient with known coronary disease requires optimization of secondary prevention 6:

• Aspirin 75-162 mg daily indefinitely 3, 6
• High-intensity statin therapy for all patients with coronary artery disease 3, 6
• Blood pressure control with goal <130/80 mmHg 3, 6
• Diabetes management if present, with HbA1c goal <7% 3
• Regular physical activity and cardiac rehabilitation 3, 6
• Avoid NSAIDs (except aspirin) due to increased cardiovascular risk 6

When to Refer for Invasive Evaluation

Consider coronary angiography if 7, 3, 6:

• High-risk features develop: Recurrent ischemia, hemodynamic instability, heart failure, or serious arrhythmias 3, 6
• Persistent or recurrent symptoms despite optimal medical therapy 3, 6
• Abnormal ECG consistent with ischemia during palpitations 7

Common Pitfalls to Avoid

• Do not dismiss palpitations as benign anxiety in a patient with known coronary disease without proper cardiac evaluation 1, 2
• Do not use immediate-release dihydropyridine calcium channel blockers (like short-acting nifedipine) without adequate beta-blockade, as they can cause reflex tachycardia and worsen ischemia 6
• Do not abruptly discontinue beta-blockers if the patient is already on them, as this can precipitate severe angina exacerbation, myocardial infarction, and ventricular arrhythmias; taper gradually over 1-2 weeks 6
• Do not assume resolved angina means resolved coronary disease—atherosclerosis is progressive and vasospasm can occur even in previously treated vessels 4, 5

Follow-Up

Schedule follow-up within 2-6 weeks to assess symptom control, medication tolerance, adherence to lifestyle modifications, and review ambulatory monitoring results 6. If serious arrhythmias or recurrent ischemia are identified, expedite cardiology referral 3, 2.