What to do for a patient with a history of stroke, erectile dysfunction (ED), heart failure (ejection fraction (EF) 41-50%), and chronic obstructive pulmonary disease (COPD) who complains of dizziness after starting pindolol (beta-blocker) and decreasing the dose, with borderline orthostatic hypotension, while on diltiazem (calcium channel blocker)?

Discontinue Diltiazem Immediately

The most critical action is to discontinue diltiazem, as calcium channel blockers like diltiazem are potentially harmful in heart failure with reduced ejection fraction and should be avoided unless absolutely necessary. 1

Rationale for Stopping Diltiazem

• Diltiazem is contraindicated in HFrEF: ESC guidelines explicitly state that "calcium-channel blockers should be discontinued unless absolutely necessary, and diltiazem and verapamil are potentially harmful because of their negative inotropic effect" in heart failure patients 1

• Dual negative chronotropic effect: The combination of pindolol (beta-blocker) and diltiazem creates additive heart rate slowing and negative inotropic effects, significantly increasing hypotension risk 1

• COPD consideration: Pindolol has intrinsic sympathomimetic activity making it less problematic for COPD than other beta-blockers, but the patient needs beta-blockade for heart failure (EF 41-50%) 2

Immediate Management Steps

1. Stop Diltiazem

• Discontinue diltiazem completely as it provides no mortality benefit in HFrEF and worsens outcomes 1
• The dizziness is likely multifactorial from the combination of two rate-controlling, blood pressure-lowering agents 1

2. Optimize Beta-Blocker Therapy

• Return pindolol to 5 mg PO BID (the original dose) after stopping diltiazem, as beta-blockers reduce mortality and hospitalizations in HFrEF 1
• Monitor for 1-2 weeks after diltiazem discontinuation before making further adjustments 1
• If dizziness persists after stopping diltiazem, then consider reducing pindolol dose 1

3. Assess for Other Contributing Factors

Check for volume depletion: 1

• Evaluate for signs of congestion (lung sounds, edema, weight trends)
• If no congestion present, consider reducing diuretic dose cautiously
• This is often the culprit in symptomatic hypotension with borderline orthostatic changes

Review all medications: 1, 3

• Identify other blood pressure-lowering agents (nitrates, alpha-blockers for BPH/ED, other vasodilators)
• Consider timing adjustments or dose reductions of non-essential hypotensive medications

Obtain ECG: 1

• Rule out heart block or excessive bradycardia (<50 bpm with symptoms)
• Assess for other cardiac causes of symptoms

Patient Education and Monitoring

• Explain that asymptomatic low blood pressure does not require treatment changes 1
• Symptomatic hypotension (dizziness, lightheadedness) requires medication adjustment, not acceptance 1
• Daily weights to detect fluid retention: increase diuretic if weight increases >1.5-2 kg over 2 days 1
• Never stop beta-blockers abruptly due to rebound risk of myocardial ischemia and arrhythmias 1, 2

Critical Pitfall to Avoid

Do not down-titrate or stop the beta-blocker first: The 2025 ESC Heart Failure Association guidelines emphasize that in stable patients on guideline-directed medical therapy with low blood pressure, the cause is "unlikely related to HFrEF therapy" and clinicians should "look for other aetiologies" before adjusting foundational HF medications 1. In this case, the "other aetiology" is the inappropriate addition of diltiazem, which has no role in HFrEF management and directly contradicts evidence-based therapy.

If Dizziness Persists After Stopping Diltiazem

• Reduce diuretic dose if no signs of congestion 1
• Only then consider halving pindolol dose temporarily (to 2.5 mg BID) 1
• Seek specialist heart failure consultation if symptoms continue despite these adjustments 1