Duration of Farxiga (Dapagliflozin) in Post-CABG Patients with Improved Heart Failure
Direct Answer
Farxiga should be continued indefinitely as lifelong therapy in your post-CABG patient, despite the improvement in ejection fraction from 30% to 44%. 1, 2
Rationale for Indefinite Continuation
No Evidence for Discontinuation Based on EF Improvement
The American College of Cardiology and American Heart Association recommend dapagliflozin for all patients with heart failure across the entire ejection fraction spectrum (HFrEF, HFmrEF, and HFpEF), with no guidance to discontinue therapy based on EF improvement. 1, 2
Your patient's EF of 44% now places them in the heart failure with mildly reduced ejection fraction (HFmrEF) category, for which dapagliflozin demonstrated an 18% reduction in cardiovascular death or worsening heart failure in the DELIVER trial. 3, 4
Patients with heart failure with improved ejection fraction (HFimpEF)—defined as prior LVEF ≤40% that increased to >40%—experienced a 62% reduction in sudden cardiac death with dapagliflozin (HR 0.38,95% CI 0.18-0.79) in post-hoc analysis of the DELIVER trial. 5
Ongoing Cardiovascular and Mortality Benefits
Dapagliflozin provides an estimated 2.3-year gain in event-free survival (95% CI: 0.9-3.8 years) for patients with heart failure and EF >40%, with benefits maintained regardless of background medical therapy including post-revascularization status. 6
The medication reduces all-cause mortality by 31% in heart failure patients, cardiovascular death by 18%, and heart failure hospitalizations by 30%, with benefits that are completely independent of diabetes status. 1, 3
These mortality and morbidity benefits persist across the entire LVEF spectrum, including patients with EF 41-49% (your patient's current range) and those with EF ≥50%. 7
Mechanism-Based Rationale
Dapagliflozin's cardiovascular benefits occur through direct cardiac effects beyond glucose lowering, including improved myocardial energetics through ketone utilization, reduced cardiac fibrosis, and prevention of adverse remodeling—mechanisms that remain relevant even after EF improvement. 8
The drug provides ongoing kidney protection by slowing eGFR decline by 1.4 mL/min/1.73 m² per year compared to placebo, which is particularly important in post-CABG patients at risk for progressive kidney disease. 9
Critical Clinical Considerations
Safety Profile Supports Long-Term Use
Dapagliflozin has minimal blood pressure effects, no excess kidney adverse events, and low risk of hypoglycemia, making it suitable for indefinite continuation even in patients on multiple guideline-directed medical therapies. 1, 8
The medication can be safely continued with eGFR as low as 25 mL/min/1.73 m², with no dose adjustment required for age, sex, or background therapy. 2, 3
Common Pitfall to Avoid
Do not discontinue dapagliflozin based on EF improvement—this is a critical error. The improved EF likely reflects the combined benefits of CABG revascularization and optimal medical therapy including dapagliflozin, but the patient remains at high risk for recurrent heart failure events and cardiovascular death without continued SGLT2 inhibitor therapy. 5, 7
If you observe a mild, transient decrease in eGFR after initiation or during follow-up, this does not indicate kidney injury and should not prompt discontinuation, as this represents expected hemodynamic effects that provide long-term kidney protection. 2, 8
Practical Implementation
Continue dapagliflozin 10 mg once daily indefinitely as part of comprehensive guideline-directed medical therapy for heart failure. 1, 3
Monitor renal function periodically and assess for signs of volume depletion, but expect and accept mild eGFR fluctuations as part of the drug's renoprotective mechanism. 2, 9
Ensure the patient remains on other evidence-based therapies (ACE inhibitor/ARB/ARNI, beta-blocker, mineralocorticoid receptor antagonist as appropriate), as dapagliflozin provides incremental benefit regardless of background therapy. 1, 3