How to manage hypotension in a patient with Dilated Cardiomyopathy (DCM) and a reduced Ejection Fraction (EF) of 35%?

Management of Hypotension in Dilated Cardiomyopathy with EF of 35%

For patients with dilated cardiomyopathy (DCM) and reduced ejection fraction (EF) of 35% who have hypotension, first assess if the patient is asymptomatic or has mild symptoms versus severe symptoms, then adjust guideline-directed medical therapy (GDMT) accordingly, with SGLT2 inhibitors and mineralocorticoid receptor antagonists (MRAs) as first-line agents since they have minimal effect on blood pressure. 1

Initial Assessment

When managing hypotension in DCM with reduced EF:

1. Determine symptom severity:

   • Asymptomatic/mild symptoms: Dizziness upon standing
   • Severe symptoms: Significant orthostatic hypotension, fatigue, dizziness, SBP <80 mmHg

2. Evaluate for non-HF causes of hypotension:

   • Medications: Alpha-blockers for BPH, antidepressants
   • Valvular disease
   • Myocardial ischemia

3. Assess congestion status:

   • Clinical, biological, or ultrasound signs of congestion
   • If no congestion, consider cautious diuretic reduction

Management Algorithm Based on Symptom Severity

For Asymptomatic/Mildly Symptomatic Low BP:

1. First-line medications (minimal BP impact):

   • Initiate SGLT2 inhibitor
   • Add MRA (if not already on one)

2. Second-line approach:

   • Start low-dose beta-blocker if HR >70 bpm OR
   • Start low-dose ACEI/ARB/ARNI

3. Titration strategy:

   • Up-titrate weekly with small increments
   • Target highest tolerated dose
   • Sometimes BP improves with increased cardiac output, allowing easier up-titration

For Severe Symptomatic Hypotension (SBP <80 mmHg):

1. Immediate action:

   • Refer to HF specialist/Advanced HF program
   • Consider temporary reduction or cessation of BP-lowering agents

2. Medication adjustment based on eGFR and heart rate:

   • If eGFR >30 ml/m² & HR >60: Start with MRA, then beta-blocker
   • If eGFR >30 ml/m² & HR <60: Reinitiate or up-titrate beta-blocker, then ACEI/ARB/ARNI
   • If eGFR <30 ml/m² & HR >60: Up-titrate beta-blocker if HR >50, then ACEI/ARB/ARNI
   • If eGFR <30 ml/m² & HR <60: Add SGLT2i if eGFR >20 ml/m², then ACEI/ARB/ARNI

Special Considerations

1. Pharmacologic options for severe hypotension:

   • Consider midodrine for symptomatic orthostatic hypotension when standard clinical care has failed 2
   • Start at lowest dose and monitor for supine hypertension

2. Patient education:

   • Reassure that transient dizziness is a side effect of life-prolonging medications
   • Explain importance of maintaining GDMT despite mild symptoms

3. Common pitfalls to avoid:

   • Unnecessarily discontinuing GDMT in asymptomatic or mildly symptomatic patients
   • Failing to identify non-HF causes of hypotension
   • Not recognizing that SGLT2i and MRAs have minimal BP-lowering effects and may actually increase BP in some patients with low BP 1

4. When to reduce or stop therapy:

   • Only when SBP <80 mmHg or with significant symptoms despite optimization
   • Start with the least tolerated medication first

Monitoring and Follow-up

1. Regular monitoring:

   • BP, heart rate, symptoms
   • Renal function and electrolytes
   • Clinical signs of congestion

2. Titration schedule:

   • Up-titrate one drug at a time
   • Small increments every 1-2 weeks
   • Close observation and follow-up

Remember that asymptomatic or mildly symptomatic low BP should not be a reason to reduce or stop GDMT, as these medications provide mortality benefit even in patients with low baseline BP 1. The goal is to maintain as much life-saving therapy as possible while managing symptoms appropriately.