In a 69-year-old obese man with a history of atrial fibrillation treated by two catheter ablations, a dual-chamber pacemaker, a Watchman left-atrial appendage occlusion device, and current therapy with diltiazem (Cardizem) XR, metoprolol succinate, and molsidomine (Moltec), who now experiences frequent premature atrial and ventricular contractions causing anxiety managed with lorazepam, is the anxiety likely secondary to his cardiac history and what alternative anxiolytic or antiarrhythmic medications are appropriate?

Management of PACs/PVCs and Anxiety in Post-Ablation Atrial Fibrillation Patient

Your patient's anxiety is most likely secondary to his extensive cardiac history, and the current use of lorazepam is appropriate only for short-term management (up to 4 months per FDA labeling); for ongoing management, consider optimizing his rate control medications first, as his current regimen of both diltiazem 120mg and metoprolol 100mg may be contributing to heightened awareness of ectopic beats, and if symptoms persist despite rate optimization, consider adding a selective serotonin reuptake inhibitor (SSRI) for long-term anxiety management rather than continuing benzodiazepines. 1

Understanding the Clinical Context

Your patient has achieved excellent rhythm control—he's been AF-free for a year post-second ablation with only very brief (<30 second) runs detected by his pacemaker. This is a success story. The PACs and PVCs he's experiencing now are extremely common, even in patients without any cardiac history, and are generally benign in the absence of structural heart disease or sustained arrhythmias.

Why the Anxiety is Likely Psychological

Given his eight-year journey through:

• Progressive atrial fibrillation
• Failed cardioversions (three attempts)
• Two ablation procedures
• Pacemaker implantation
• Watchman device placement

It's entirely reasonable that he's developed hypervigilance about cardiac symptoms. This is a well-recognized phenomenon in patients who've experienced significant cardiac events—they become acutely aware of every heartbeat irregularity that most people would never notice.

The Lorazepam Problem

The FDA labeling for lorazepam is clear: it's indicated for "short-term relief" of anxiety symptoms, and "the effectiveness of lorazepam in long-term use, that is, more than 4 months, has not been assessed by systematic clinical studies." 1 Your patient appears to be using this chronically, which raises concerns about:

• Tolerance development
• Dependence risk
• Cognitive effects (particularly important in a 69-year-old)
• Fall risk (he's already had issues with obesity and now takes a sedative)

Medication Optimization Strategy

Step 1: Evaluate Current Rate Control Regimen

Your patient is on both diltiazem 120mg XR and metoprolol 100mg. This dual rate-control approach is reasonable per guidelines 2, 3, 4, but consider:

• Is his resting heart rate too low? Excessive bradycardia can paradoxically make patients more aware of ectopic beats
• Check his pacemaker settings: Ensure the lower rate limit isn't causing pauses that trigger compensatory PACs/PVCs
• Guidelines recommend rate control targets of 60-80 bpm at rest and 90-115 bpm with moderate exercise 2, 3

The combination of beta-blocker and calcium channel blocker should be individualized and "the dose modulated to avoid bradycardia" per Class IIa recommendations 2, 3, 4

Step 2: Consider Medication Adjustment

Recent evidence suggests metoprolol may have a better adverse event profile than diltiazem in some contexts 5, though diltiazem shows superior rate control efficacy 6, 7. However, in your patient who already has adequate rate control (he's in sinus rhythm), the focus should shift from aggressive rate control to symptom management.

Practical approach:

• Review his ambulatory heart rate patterns via pacemaker interrogation
• If resting rates are consistently <60 bpm, consider reducing one agent
• Beta-blockers can sometimes increase awareness of ectopic beats in sensitive patients

Step 3: Address the Anxiety Directly

For long-term anxiety management in cardiac patients, SSRIs are preferred over benzodiazepines. Consider:

• Sertraline or escitalopram as first-line agents
  • Well-tolerated in cardiac patients
  • No significant drug interactions with his current regimen
  • Effective for generalized anxiety disorder
  • Takes 4-6 weeks for full effect

Transition strategy:

• Start SSRI at low dose
• Continue lorazepam 0.5mg as needed during SSRI titration
• Gradually taper lorazepam over 4-8 weeks once SSRI reaches therapeutic effect
• Provide reassurance and education about benign nature of PACs/PVCs

What NOT to Do

Do not add antiarrhythmic drugs for PACs/PVCs alone. The guidelines are clear that antiarrhythmic therapy should be reserved for patients with "disabling or otherwise troublesome symptoms during AF" and should be based "predominantly on safety" 8. Your patient is not in AF—he's having normal ectopic beats that are causing anxiety, not hemodynamic compromise.

Adding drugs like:

• Flecainide or propafenone (Class IC agents)
• Sotalol or dofetilide (Class III agents)
• Amiodarone

Would expose him to proarrhythmic risk (including potentially life-threatening ventricular arrhythmias) for a benign condition. This violates the fundamental principle of "first, do no harm."

Common Pitfalls to Avoid

1. Over-treating benign ectopy: PACs and PVCs are nearly universal and don't require treatment unless causing symptoms that significantly impair quality of life or leading to cardiomyopathy

2. Chronic benzodiazepine use: Creates more problems than it solves in the long run

3. Ignoring the psychological component: This patient has been through cardiac trauma; addressing the anxiety disorder directly is more appropriate than adding cardiac medications

4. Assuming all palpitations are dangerous: With his Watchman device, pacemaker, and successful ablation, his stroke risk is managed and his rhythm is controlled

Recommended Action Plan

1. Pacemaker interrogation: Review for:

   • Actual burden of PACs/PVCs (often less than patient perceives)
   • Appropriate lower rate limit settings
   • Any pacemaker-mediated triggers

2. Medication review:

   • Consider reducing rate control if resting HR consistently <60 bpm
   • Ensure no drug interactions or QT prolongation

3. Initiate SSRI therapy:

   • Start sertraline 25-50mg daily or escitalopram 5-10mg daily
   • Plan for gradual lorazepam taper over 4-8 weeks

4. Patient education and reassurance:

   • Explain that PACs/PVCs are benign and extremely common
   • Emphasize his excellent rhythm control success
   • Discuss the psychological component openly

5. Follow-up in 4-6 weeks:

   • Assess SSRI response
   • Monitor lorazepam taper
   • Repeat symptom assessment

This approach addresses both the physiological and psychological components of his symptoms while avoiding unnecessary cardiac medications that carry significant risk without clear benefit in his current clinical state.