What is the best management approach for a 79-year-old patient with coronary disease, atrial fibrillation (AF) with rapid ventricular response (RVR), diabetes mellitus type 2, chronic kidney disease (CKD) stage 3, and vascular disease, currently on aspirin (acetylsalicylic acid) and metoprolol (beta-blocker)?

Management of Atrial Fibrillation with Rapid Ventricular Response in a High-Risk Elderly Patient

Increase the metoprolol dose immediately and add digoxin for acute rate control, while initiating anticoagulation with a DOAC given the high stroke risk.

Immediate Rate Control Strategy

Your patient is on an inadequate dose of metoprolol (25 mg once daily) for AF with RVR at 125 bpm. Beta-blockers are the Class I recommended first-line agents for rate control in AF, particularly in patients with coronary disease 1. However, the current dose is insufficient.

Acute Rate Control Options:

• Intravenous metoprolol: Administer 2.5-5 mg IV bolus over 2 minutes, up to 3 doses as needed to achieve rate control 1
• Oral metoprolol uptitration: Increase to 25-100 mg twice daily for maintenance 1
• Add IV digoxin: 0.5 mg IV bolus (0.75-1.5 mg over 24 hours in divided doses) is Class I recommended for acute rate control in patients with coronary disease and multiple comorbidities 1, 2

Digoxin is particularly appropriate here because your patient has coronary disease, CKD stage 3, and is relatively sedentary (high fall risk), making it effective for resting heart rate control 1, 2. The combination of digoxin plus beta-blocker is Class IIa recommended to control both resting and exercise heart rate 1, 2.

Critical Precautions with Beta-Blockers:

Monitor closely for:

• Bradycardia and heart block - beta-blockers can cause sinus pause and cardiac arrest 3
• Hypotension - use caution given vascular disease 3
• Worsening heart failure - beta-blockers can depress myocardial contractility 3
• Hypoglycemia masking - particularly relevant with diabetes type 2 3

Adjust digoxin dose for CKD stage 3: Check renal function and reduce dose accordingly, as digoxin clearance is reduced in renal impairment 1. Target dose 0.0625-0.25 mg daily with monitoring of serum levels 1.

Avoid Calcium Channel Blockers

Do not use diltiazem or verapamil in this patient. While non-dihydropyridine calcium channel blockers are generally effective for rate control 1, they are relatively contraindicated here because:

• Your patient has coronary disease with likely some degree of LV dysfunction 1
• The combination of vascular disease, diabetes, and CKD suggests possible subclinical heart failure 1
• Calcium channel blockers should not be used in decompensated HF as they may exacerbate hemodynamic compromise (Class III: Harm) 1, 2

Anticoagulation is Mandatory

This patient has a CHA₂DS₂-VASc score of at least 6-7 (age 79 = 2 points, coronary disease/vascular disease = 1 point, diabetes = 1 point, male = 0 points, plus likely hypertension and heart failure given the clinical picture) 1.

Anticoagulation Strategy:

• Stop aspirin monotherapy immediately - it is inadequate for stroke prevention in high-risk AF 1
• Initiate a DOAC (direct oral anticoagulant) in preference to warfarin 1
• Dose-adjust the DOAC for CKD stage 3: Most DOACs require dose reduction at CrCl 30-50 mL/min 4
• Warfarin is an acceptable alternative if DOAC is contraindicated, targeting INR 2.0-3.0 1

CKD increases stroke risk across all CHA₂DS₂-VASc strata, and anticoagulation with warfarin has been shown to reduce all-cause mortality in CKD patients with CHA₂DS₂-VASc ≥2 5. The high fall risk does not contraindicate anticoagulation when stroke risk is this elevated 1.

Rhythm Control Consideration

Electrical cardioversion is NOT indicated unless the patient becomes hemodynamically unstable (hypotension, acute heart failure, ongoing ischemia) 1. Your patient is currently stable enough for pharmacologic rate control.

If cardioversion is eventually considered:

• Therapeutic anticoagulation for at least 3 weeks is required before elective cardioversion 1
• Alternatively, perform TEE to exclude thrombus if earlier cardioversion is desired 1
• Continue anticoagulation for at least 4 weeks post-cardioversion and long-term given stroke risk factors 1

Monitoring Plan

• Assess heart rate during activity, not just at rest - adjust medications to maintain physiologic rate during exercise 1
• Target resting heart rate <100-110 bpm initially (lenient control is reasonable if patient remains asymptomatic) 1
• Monitor renal function closely when initiating digoxin and DOAC 1, 4
• Check digoxin levels if toxicity suspected (GI upset, visual changes, arrhythmias) 1

Common Pitfalls to Avoid

• Do not use dronedarone for rate control in permanent AF - it increases stroke, MI, and cardiovascular death (Class III: Harm) 1
• Do not perform AV node ablation without first attempting pharmacologic rate control (Class III: Harm) 1
• Do not abruptly discontinue beta-blocker if later switching agents - taper over 1-2 weeks to avoid rebound ischemia 3
• Do not underdose the DOAC - use DOAC-specific criteria for dose reduction, not arbitrary reductions 1