Would you use a Sodium-Glucose Linked Transporter 2 inhibitor (SGLT2i) for a patient with left ventricular dysfunction or heart failure, particularly with a history of diabetes or at high risk for cardiovascular events?

SGLT2 Inhibitors for Left Ventricular Dysfunction and Heart Failure

Yes, you should absolutely give an SGLT2 inhibitor to this patient—SGLT2 inhibitors are Class 1A recommended therapy for patients with heart failure and left ventricular dysfunction, regardless of diabetes status, to reduce cardiovascular death and heart failure hospitalization. 1, 2

Primary Indication Based on Left Ventricular Function

For patients with LVEF ≤40% (HFrEF):

• SGLT2 inhibitors are mandatory guideline-directed medical therapy to reduce cardiovascular death and heart failure hospitalization 1
• Empagliflozin reduced heart failure hospitalization by 35% and cardiovascular death by 38% in EMPA-REG OUTCOME 1, 3
• Dapagliflozin reduced the composite of worsening heart failure or cardiovascular death by 26% in DAPA-HF 3
• This benefit occurs regardless of diabetes status—the indication exists even without diabetes 1, 2

For patients with LVEF >40% (HFpEF or mildly reduced EF):

• SGLT2 inhibitors are Class 2a recommended to decrease heart failure hospitalizations and improve quality of life 1
• Dapagliflozin reduced the composite outcome by 27% and heart failure hospitalization by 21% in DELIVER, regardless of LVEF level 4
• This represents the first pharmacological class proven effective in HFpEF 4

Diabetes-Specific Considerations

If the patient has type 2 diabetes:

• SGLT2 inhibitors are first-line agents for glycemic control in patients with heart failure or at high risk for heart failure 1
• They should be used to prevent incident heart failure in patients with diabetes and established cardiovascular disease or high cardiovascular risk 1
• The American Diabetes Association specifically recommends SGLT2 inhibitors as first-line therapy for hyperglycemia in patients with diabetes and heart failure 1

If the patient does NOT have diabetes:

• SGLT2 inhibitors are still indicated for heart failure with LVEF ≤40% 1, 2
• The cardiovascular benefits appear independent of the glucosuric effect 1

Specific Agent Selection

Either empagliflozin or dapagliflozin are appropriate choices:

• Guidelines recommend SGLT2 inhibitors as a class without preferential recommendation for one agent over another 3
• Empagliflozin 10 mg daily or dapagliflozin 10 mg daily are the standard doses 2
• Canagliflozin also reduces heart failure hospitalization by 33%, though it carries an increased amputation risk 1, 5
• Avoid ertugliflozin as it showed lesser cardiovascular benefits 1

Timing of Initiation

Start SGLT2 inhibitors immediately, including during hospitalization:

• SGLT2 inhibitors should be initiated during hospitalization for acute decompensated heart failure—do not defer to outpatient setting 2
• Deferring in-hospital initiation exposes patients to excess risk of early post-discharge clinical worsening and death 2
• Benefits are incremental and consistent regardless of background medical therapy 2

Contraindications and Precautions

Do NOT initiate if:

• eGFR <30 mL/min/1.73m² (though may continue if already established) 2
• Pregnancy or breastfeeding 2
• Serious hypersensitivity reaction to the agent 5

Withhold temporarily:

• At least 3 days prior to surgery or procedures with prolonged fasting 5
• Resume when clinically stable and oral intake resumed 5

Monitor closely for:

• Genital mycotic infections and urinary tract infections (common adverse effects) 3
• Euglycemic diabetic ketoacidosis, particularly before surgery or during acute illness 3, 5
• Volume status before initiation to prevent hypotension 3
• Renal function and electrolytes 1-2 weeks after initiation 2

Critical Pitfall to Avoid

Do not withhold SGLT2 inhibitors based on:

• Presence of mitral regurgitation—the etiology of heart failure does not change the indication 2
• Absence of diabetes—benefits extend to non-diabetic patients with HFrEF 1, 2
• Concern about "adding another medication"—SGLT2 inhibitors reduce mortality and should be prioritized 2

Dose Adjustments

If patient is on insulin or sulfonylureas:

• Reduce insulin or sulfonylurea doses by approximately 20% when initiating SGLT2 inhibitors to prevent hypoglycemia 3

If patient is on UGT enzyme inducers (rifampin, phenytoin, phenobarbital, ritonavir):

• Increase canagliflozin dosage based on renal function (up to 200-300 mg daily if eGFR permits) 5