Guidelines summarize and evaluate all available evidence on a particular issue at the time of the writing process, with the aim of assisting health professionals in selecting the best management strategies for an individual patient with a given condition, taking into account the impact on outcome, as well as the risk–benefit ratio of particular diagnostic or therapeutic means. Guidelines and recommendations should help health professionals to make decisions in their daily practice. However, the final decisions concerning an individual patient must be made by the responsible health professional(s) in consultation with the patient and caregiver as appropriate.

Natriuretic peptide [NP; B-type NP (BNP), N-terminal proBNP (NT-proBNP), and midregional proANP (MR-proANP)] concentrations are quantitative plasma biomarkers for the presence and severity of haemodynamic cardiac stress and heart failure (HF). End-diastolic wall stress, intracardiac filling pressures, and intracardiac volumes seem to be the dominant triggers. This paper details the most important indications for NPs and highlights 11 key principles underlying their clinical use shown below. (i)NPs should always be used in conjunction with all other clinical information.(ii)NPs are reasonable surrogates for intracardiac volumes and filling pressures.(iii)NPs should be measured in all patients presenting with symptoms suggestive of HF such as dyspnoea and/or fatigue, as their use facilitates the early diagnosis and risk stratification of HF.(iv)NPs have very high diagnostic accuracy in discriminating HF from other causes of dyspnoea: the higher the NP, the higher the likelihood that dyspnoea is caused by HF.(v)Optimal NP cut-off concentrations for the diagnosis of acute HF (very high filling pressures) in patients presenting to the emergency department with acute dyspnoea are higher compared with those used in the diagnosis of chronic HF in patients with dyspnoea on exertion (mild increase in filling pressures at rest).(vi)Obese patients have lower NP concentrations, mandating the use of lower cut-off concentrations (about 50% lower).(vii)In stable HF patients, but also in patients with other cardiac disorders such as myocardial infarction, valvular heart disease, atrial fibrillation or pulmonary embolism, NP concentrations have high prognostic accuracy for death and HF hospitalization.(viii)Screening with NPs for the early detection of relevant cardiac disease including left ventricular systolic dysfunction in patients with cardiovascular risk factors may help to identify patients at increased risk, therefore allowing targeted preventive measures to prevent HF.(ix)BNP, NT-proBNP and MR-proANP have comparable diagnostic and prognostic accuracy.(x)In patients with shock, NPs cannot be used to identify cause (e.g. cardiogenic vs. septic shock), but remain prognostic.(xi)NPs cannot identify the underlying cause of HF and, therefore, if elevated, must always be used in conjunction with cardiac imaging.

Background: Perioperative myocardial injury (PMI) seems to be a contributor to mortality after noncardiac surgery. Because the vast majority of PMIs are asymptomatic, PMI usually is missed in the absence of systematic screening. Methods: We performed a prospective diagnostic study enrolling consecutive patients undergoing noncardiac surgery who had a planned postoperative stay of ≥24 hours and were considered at increased cardiovascular risk. All patients received a systematic screening using serial measurements of high-sensitivity cardiac troponin T in clinical routine. PMI was defined as an absolute high-sensitivity cardiac troponin T increase of ≥14 ng/L from preoperative to postoperative measurements. Furthermore, mortality was compared among patients with PMI not fulfilling additional criteria (ischemic symptoms, new ECG changes, or imaging evidence of loss of viable myocardium) required for the diagnosis of spontaneous acute myocardial infarction versus those that did. Results: From 2014 to 2015 we included 2018 consecutive patients undergoing 2546 surgeries. Patients had a median age of 74 years and 42% were women. PMI occurred after 397 of 2546 surgeries (16%; 95% confidence interval, 14%–17%) and was accompanied by typical chest pain in 24 of 397 patients (6%) and any ischemic symptoms in 72 of 397 (18%). Crude 30-day mortality was 8.9% (95% confidence interval [CI], 5.7–12.0) in patients with PMI versus 1.5% (95% CI, 0.9–2.0) in patients without PMI ( P <0.001). Multivariable regression analysis showed an adjusted hazard ratio of 2.7 (95% CI, 1.5–4.8) for 30-day mortality. The difference was retained at 1 year with mortality rates of 22.5% (95% CI, 17.6–27.4) versus 9.3% (95% CI, 7.9–10.7). Thirty-day mortality was comparable among patients with PMI not fulfilling any other of the additional criteria required for spontaneous acute myocardial infarction (280/397, 71%) versus those with at least 1 additional criterion (10.4%; 95% CI, 6.7–15.7, versus 8.7%; 95% CI, 4.2–16.7; P =0.684). Conclusions: PMI is a common complication after noncardiac surgery and, despite early detection during routine clinical screening, is associated with substantial short- and long-term mortality. Mortality seems comparable in patients with PMI not fulfilling any other of the additional criteria required for spontaneous acute myocardial infarction versus those patients who do. Clinical Trial Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02573532.

Aim It is unknown whether cardiac troponin (cTn) I or cTnT is the preferred biomarker in the early diagnosis of acute myocardial infarction without ST segment elevation (NSTEMI). Methods and results In a prospective multicentre study, we measured cTnI and cTnT using clinically available high-sensitivity assays (hs-cTnI Abbott and hs-cTnT Roche) and compared their diagnostic and prognostic accuracies in consecutive patients presenting to the emergency department with acute chest pain. The final diagnosis was adjudicated by two independent cardiologists using all information pertaining to the individual patient. The mean follow-up was 24 months. Among 2226 consecutive patients, 18% had an adjudicated final diagnosis of NSTEMI. Diagnostic accuracy at presentation as quantified by the area under the receiver-operating-characteristics curve (AUC) for NSTEMI was very high and similar for hs-cTnI [AUC: 0.93, 95% confidence interval (CI) 0.92–0.94] and hs-cTnT (0.94, 95% CI: 0.92–0.94) P = 0.62. In early presenters (<3 h since chest pain onset) hs-cTnI showed a higher diagnostic accuracy (AUC: 0.92, 95% CI: 0.89–0.94) when compared with hs-cTnT AUC (0.89, 95% CI: 0.86–0.91) ( P = 0.019), while hs-cTnT was superior in late presenters [AUC hs-cTnT 0.96 (95% CI: 0.94–0.96) vs. hs-cTnI 0.94 (95% CI: 0.93–0.95); P = 0.007]. The prognostic accuracy for all-cause mortality, quantified by AUC, was significantly higher for hs-cTnT (AUC: 0.80; 95% CI: 0.78–0.82) when compared with hs-cTnI (AUC: 0.75; 95% CI: 0.73–0.77; P < 0.001). Conclusion Both hs-cTnI and hs-cTnT provided high diagnostic and prognostic accuracy. The direct comparison revealed small but potentially important differences that might help to further improve the clinical use of hs-cTn.