Introduction: Both sepsis and acute decompensated heart failure (ADHF) can present with organ dysfunction. In sepsis, this is due to a dysregulated host response to infection, and in ADHF, it is due to structural or functional changes in the heart leading to an inability to meet metabolic demands. Lactic acidosis is rare in ADHF. In fact, Adamo et al. found that lactate levels were normal in approximately 75% of patients with ADHF in their study (1).

Case Presentation: 65-year-old with history of tobacco abuse, obesity, hypertension, hyperlipidemia, diabetes and atrial fibrillation presented with shortness of breath, bilateral lower extremity edema +1, and noted cyanosis in the 1st to 3rd phalanx bilaterally. He was hypertensive and tachycardic with WBC count of 12,000 cells/μL, lactic acid of 9.4 mmol/L, BNP of 2271 pg/mL, and creatinine at 2.7 mg/dL. Chest X-ray revealed cardiomegaly and a small right pleural effusion. The patient met sepsis criteria with multiple organ dysfunction, with urinalysis pending at that point. Point of care ultrasound (POCUS) showed moderate right sided effusion and mildly reduced ejection fraction.

Management: We started the patient on 150 mEq potassium bicarbonate with D5W at 75 ml/hr while obtaining further results. Follow-up laboratory results worsened, with the clinical picture leaning towards ADHF. He was then treated with IV Lasix 40 mg qd, which led to clinical and laboratory improvement. Eventually, the echocardiogram revealed a reduced EF of 40-45%, TAPSE of 1.48, and RSVP of 24.

Significant lactic acidosis due to ADHF is rarely described in the literature and can be a confounding factor if there is high suspicion of sepsis. This case highlights the limitations of sepsis definitions, as they cannot always identify patients whose organ dysfunction is truly secondary to an underlying infection. Sometimes sepsis can only be diagnosed or ruled out after a constellation of clinical, laboratory, radiologic, physiologic, and microbiologic data returns. During this turnaround time, physicians need to be conservative with their management to avoid fluid overloading a patient with heart failure or diuresing a septic patient. The use of POCUS may increase speed and accuracy of diagnosis in patients with mixed clinical presentation.

References and Resources

1. Adamo L, Nassif ME, Novak E, LaRue SJ, Mann DL. Prevalence of lactic acidaemia in patients with advanced heart failure and depressed cardiac output. Eur J Heart Fail. 2017 Aug;19(8):1027-1033. doi: 10.1002/ejhf.628. Epub 2016 Sep 20. PMID: 27647751; PMCID: PMC5359085.