Copeptin for the differentiation of type 1 versus type 2 myocardial infarction or myocardial injury.

BACKGROUND: The rapid and reliable differentiation of myocardial infarction (MI) due to atherothrombosis (T1MI) from MI due to supply-demand mismatch (T2MI) or acute myocardial injury is of major clinical relevance due to very different treatments, but still a major unmet clinical need. This study aimed to investigate whether copeptin, a stress hormone produced in the hypothalamus, helps to differentiate between T1MI versus T2MI or injury. METHODS: In a retrospective analysis, 1271 unselected consecutive patients presenting with symptoms suggestive of MI to the emergency department were evaluated. Patients diagnosed with ST-elevation MI were excluded. All patients with elevated cardiac troponin I (cTnI) concentration possibly indicating MI were classified into T1MI, T2MI, or acute myocardial injury using detailed clinical assessment and coronary imaging. Copeptin plasma concentration was measured in a blinded fashion. A multicenter diagnostic study with central adjudication of the final diagnosis served as external validation cohort (n = 1390). RESULTS: Among 1161 patients, 154 patients had increased cTnI concentration. Of these, 78 patients (51%) were classified as T1MI and 76 (49%) as T2MI or myocardial injury. Patients with T2MI or myocardial injury had significantly higher copeptin plasma concentration between patients versus T1MI (21,4 pmol/l versus 8,1 pmol/l, p = 0,001). A multivariable regression analysis revealed that higher concentrations of copeptin and C-reactive protein, higher heart rate at presentation and lower frequency of smoking remained significantly associated with T2MI and myocardial injury. Findings were largely confirmed in the external validation cohort. CONCLUSION: In patients without ST-segment elevation, copeptin concentration was higher in T2MI and myocardial Injury versus T1MI and may help in their differential diagnosis.

Influence of previous coronary artery bypass grafting in the difficulty of acute coronary syndrome diagnosis.

OBJECTIVES: To investigate whether the diagnosis of acute coronary syndrome (ACS) in coronary artery bypass grafting (CABG) patients with chest pain (CP) is more difficult based on the initial clinical and electrocardiogram (ECG) findings. METHODS: We included consecutive CP patients attended at a single emergency department (ED) during a 10-year period. CABG status and the final diagnosis of ACS were considered as stated in the ED discharge report. We evaluated the frequency of 21 CP characteristics (CPC) and four ECG signatures, their individual and collective association with ACS, and ED length of stay (LOS) in CABG and non-CABG patients. RESULTS: We included 34 429 patients [median age: 61 years; female: 41.8%; CABG: 2204 patients (6.4%)], and ACS was diagnosed in 6727 (19.5%; CABG/non-CABG 37.2%/18.3%; P < 0.001). CABG patients more frequently had CPC and ECG findings typically associated with ACS, but their final association with ACS was weaker than in non-CABG patients (only significant after adjustment for attendant diaphoresis, throat irradiation, ST-segment elevation and T-wave inversion). The collective discriminative capacity was significantly lower in CABG patients (area under the curve 0.710 vs. 0.793; P < 0.001), even after adjustment (0.708 vs. 0.790; P < 0.001). ED LOS was longer for CABG patients, overall (P < 0.001) and for patients diagnosed with ACS (P = 0.008) and non-ACS (P < 0.001), but these differences disappeared after adjustment. CONCLUSION: CABG substantially reduces the diagnostic performance of CPC and ECG findings to suggest ACS. A longer LOS in the ED in CABG patients is more related to their baseline characteristics than to CABG itself.

Use of cardiac troponin in the early diagnosis of acute myocardial infarction.

The diagnosis ofcoronary artery disease, which is one of the most common causes of death and disability worldwide, still remains a significant problem for clinicians. High­sensitivity cardiac troponin (hs­cTn) assays became the cornerstone in the diagnostic workup of acute myocardial infarction. Nowadays, they take an important position in diagnostic algorithms. However, there are still some unexplained issues in this field.This review summarizes and emphasizes the crucial role of hs­cTn in acute coronary syndromes. The 0/1­hour hs­cTn algorithm was mentioned for the first time in the 2015 official European Society of Cardiology guidelines on non-ST­segment­elevation acute coronary syndromes. It was derived, validated, and implemented for all clinically­available assays since then. In this review, troponin­based strategies for rapid rule­out or rule­in of non-ST­segment elevation myocardial infarction are gathered and compared with the update on the official European Society of Cardiology 0/1­hour pathway with the most recent values of hs­cTn. The document also focuses on the problem of possible analytic confounders (false­­positive and false­negative results) and compares the usefulness of cTn to other diagnostic techniques (eg, magnetic resonance imaging). The review is divided into short, easy­to­read sections emphasizing 6 key messages on how to use and interpret hs­cTn base algorithms in clinical practice at the emergency department.