High Sensitivity cTnT Rules Out Cardiac Insufficiency Trial (TACIT)

Hospitalization for acute heart failure (AHF) results in a high rate of post-discharge mortality and re-admissions, as well as high financial costs. Reducing 30-day re-admissions after AHF hospitalization is a major national quality goal intended to both improve patient outcomes and reduce costs.

Approximately 85% of emergency department (ED) patients with AHF are hospitalized, and 800,000 of the 1,000,000 hospitalizations for HF originate from the ED, highlighting the critical role of the ED. Even a single digit percentage (i.e. 5%) decrease in the number of AHF admissions would equate to an estimated 40,000 fewer hospitalizations.

Why are so many AHF patients hospitalized? AHF patients have a high post-discharge event rate. Emergency physicians have a low risk tolerance. When both are combined, most patients are admitted. The absence of risk scores for the ED setting compounds the problem. Most risk scores were developed in the hospital. As hospitalization may affect the outcomes of patients, whether these risk scores apply to the ED setting is unknown. As a result, which patients are at lower risk in the ED has not been well-studied. Further, absence of high-risk features does not necessarily equal absolute low morbidity or mortality, though such patients are likely at lower risk. In the absence of a risk score, clinical judgment is a poor substitute and often fails to identify patients at high risk, such that those discharged from the ED may be at equal or greater risk for death than hospitalized patients. Thus, the difficulty of identifying low risk, combined with the inherent high morbidity and mortality of AHF, leads to a disproportionate number of hospitalizations.

Over a decade ago, the Agency for Healthcare Research and Policy Guidelines suggested that up to 50% of AHF patients were potential candidates for ED discharge or observation unit management. Furthermore, nearly half of all patients hospitalized for AHF present with lower-risk features such as high blood pressure (> 140mmHg) and a BNP < 1000 pg/mL. If low or lower risk ED patients with HF could be accurately identified, perhaps a greater proportion of patients with AHF could be safely discharged or observed briefly prior to discharge.

Study Rationale: With this pilot study, we will generate the necessary and sufficient pilot data to inform the design of a definitive trial to test whether identification of low risk acute heart failure (AHF) patients with negative serial high-sensitivity troponin T (hsTnT) in the ED may be safely discharged home or observed briefly in observation status.