Beta blocker use in traumatic brain injury based on the high-sensitive troponin status (BBTBBT): methodology and protocol implementation of a double-blind randomized controlled clinical trial

Background

Beta-adrenergic receptor blockers (BB) play an important role in the protection of organs that are susceptible for secondary injury due to stress-induced adrenergic surge. However, the use of BB in traumatic brain injury (TBI) patients is not yet the standard of care which necessitates clear scientific evidence to be used. The BBTBBT study aims to determine whether early administration of propranolol based on the high-sensitive troponin T(HsTnT) status will improve the outcome of TBI patients. We hypothesized that early propranolol use is effective in reducing 10- and 30-day mortality in TBI patients. Secondary outcomes will include correlation between serum biomarkers (troponin, epinephrine, cytokines, enolase, S100 calcium binding protein B) and the severity of injury and the impact of BB use on the duration of hospital stay and functional status at a 3-month period.

Methods

The BBTBBT study is a prospective, randomized, double-blinded, placebo-controlled three-arm trial of BB use in mild-to-severe TBI patients based on the HsTnT status. All enrolled patients will be tested for HsTnT at the first 4 and 6 h post-injury. Patients with positive HsTnT will receive BB if there is no contraindication (group 1). Patients with negative HsTnT will be randomized to receive either propranolol (group 2) or placebo (group 3). The time widow for receiving the study treatment is the first 24 h post-injury.

Discussion

Early BB use may reduce the catecholamine storm and subsequently the cascade of immune and inflammatory changes associated with TBI. HsTnT could be a useful fast diagnostic and prognostic tool in TBI patients. This study will be of great clinical interest to improve survival and functional outcomes of TBI patients.

Trial registration

ClinicalTrials.gov NCT04508244. Registered on 7 August 2020. Recruitment started on 29 December 2020 and is ongoing.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05872-8.

Outcomes associated with the high sensitivity cardiac troponin testing in patients presenting with non-cardiovascular disorders

There are limited data regarding the utility of troponin testing in patients presenting with non-cardiovascular (CV) symptoms as the primary manifestation. The study population comprised 2057 patients who presented to the emergency department (ED) of a US healthcare system with non-CV symptoms as the primary manifestation between January and September 2018. We compared the effect of high-sensitivity cardiac troponin T (hs-cTnT) (n = 901) after its introduction vs. 4th generation cTnT (n = 1156) on the following outcomes measures: ED length of stay (LOS), coronary tests/procedures (angiography or stress test), and long-term mortality. Mean age was 64 ± 17 yrs., and 47% were female. Primary non-CV manifestations included pneumonia, obstructive pulmonary disease, infection, abdominal-complaint, and renal failure. Mean follow up was 9 ± 4 months. Patients' demographics and medical history were clinically similar between the two troponin groups. A second cTn test was obtained more frequently in the hs-cTnT than cTnT (84% vs. 32%; p < 0.001), possibly leading to a longer ED stay (8.1 ± 8.2 h vs 5.6 ± 3.4 h, respectively; p < 0.001). Coronary tests/procedures were performed at a significantly higher rate in the hs-cTnT than cTnT following the introduction of the hs-cTnT test (28% vs. 22%, p < 0.001). Multivariate analysis showed that following the introduction of hs-cTnT testing, there was a significant 27% lower risk of long-term mortality from ED admission through follow-up (HR = 0.73, 95%CI 0.54-0.98; p = 0.035). In conclusion, we show that in patients presenting primarily with non-CV disorders, the implementation of the hs-cTnT was associated with a higher rate of diagnostic coronary procedures/interventions, possibly leading to improved long-term survival rates.

Comparison of Perioperative High-Sensitive Troponin T and Troponin I Assays in Cardiac Surgery

BACKGROUND

Troponin measurements are among the standard parameters for monitoring perioperative myocardial ischaemia after cardiosurgical procedures. As high-sensitive assays continue to replace older analytic parameters with lower sensitivity, this study aimed to compare perioperative profiles of a high-sensitive troponin T assay (hsTnT, Roche Diagnostics, Mannheim, Germany) with a troponin I assay (sTnI, Siemens Healthcare Diagnostics, Eschborn, Germany).

METHODS

A total of 287 consecutive patients undergoing a typical spectrum of cardiac procedures from August 2017 to March 2018 monitored with the hsTnT assay were compared with a propensity-matched collective analysed with the sTnI assay. For side-by side comparison, the peak troponin (Tmax) values were scaled to a z-score distribution before comparison.

RESULTS

Despite absolute postoperative hsTnT and sTnI values differing by an order of magnitude, parameters could be scaled to a common distribution with kernel density curves overlapping 92%. Both parameters showed equal behaviour in subgroup analyses regarding relevant perioperative factors, such as type of procedure, cross-clamping time, and type of cardioplegic solution. However, there were some differences regarding pre-existing renal impairment between both parameters. In both groups, renal failure patients with chronic kidney disease stages IV or V as well as patients on haemodialysis exhibited a marked Tmax increase of >100% compared with normal kidney function (hsTnT, +121%; 2,383.5 vs 1,078.8 ng/L; p=0.0006; and sTnI, +149%; 27.3 ng/mL vs 11.0 ng/mL; p=0.009). However, in patients with moderately impaired renal function, those in the hsTnT group, but not in the sTnI cohort, showed significantly increased Tmax values (CKD stages II or III, 1,233.5 ng/L [+14%] and 1,314.1 ng/L [+22%] vs 1,078.8 ng/L; p=0.01 and p=0.03). In these patients, the postoperative interval until Tmax was reached was also significantly increased (14.4 and 19.0 hrs vs 12.4 hrs for chronic kidney disease stages II and III; p=0.0038 and p<0.001), indicating a higher rate of accumulation in the hsTnT parameter.

CONCLUSION

In the context of cardiac surgery, this study found that both parameters behaved in a similar manner under most relevant circumstances. Despite significant difference in the absolute serum concentration, hsTnT and sTnI can be scaled to virtually identical distributions. However, renal impairment did affect both parameters differently with troponin T but not troponin I, showing evidence of accumulation in moderately impaired renal disease.

microRNA neural networks improve diagnosis of acute coronary syndrome (ACS)

BACKGROUND

Cardiac troponins are the preferred biomarkers of acute myocardial infarction. Despite superior sensitivity, serial testing of Troponins to identify patients suffering acute coronary syndromes is still required in many cases to overcome limited specificity. Moreover, unstable angina pectoris relies on reported symptoms in the troponin-negative group. In this study, we investigated genome-wide miRNA levels in a prospective cohort of patients with clinically suspected ACS and determined their diagnostic value by applying an in silico neural network.

METHODS

PAXgene blood and serum samples were drawn and hsTnT was measured in patients at initial presentation to our Chest-Pain Unit. After clinical and diagnostic workup, patients were adjudicated by senior cardiologists in duty to their final diagnosis: STEMI, NSTEMI, unstable angina pectoris and non-ACS patients. ACS patients and a cohort of healthy controls underwent deep transcriptome sequencing. Machine learning was implemented to construct diagnostic miRNA classifiers.

RESULTS

We developed a neural network model which incorporates 34 validated ACS miRNAs, showing excellent classification results. By further developing additional machine learning models and selecting the best miRNAs, we achieved an accuracy of 0.96 (95% CI 0.96-0.97), sensitivity of 0.95, specificity of 0.96 and AUC of 0.99. The one-point hsTnT value reached an accuracy of 0.89, sensitivity of 0.82, specificity of 0.96, and AUC of 0.96.

CONCLUSIONS

Here we show the concept of neural network based biomarkers for ACS. This approach also opens the possibility to include multi-modal data points to further increase precision and perform classification of other ACS differential diagnoses.

The HEART score with high-sensitive troponin T at presentation: ruling out patients with chest pain in the emergency room

The HEART score is a simple scoring system, ranging from 0 to 10, specifically developed for risk stratification of patients with undifferentiated chest pain. It has been validated for the conventional troponin, but not for high-sensitive troponin. We assess a modified version of the HEART score using a single high-sensitivity troponin T dosage at presentation, regardless of symptom duration, and with different ECG criteria to evaluate if the patients with a low HEART score could be safely discharged early. The secondary aim was to confirm a statistically significant difference in each HEART score group (low 0-3, intermediate 4-6, high 7-10) in the occurrence of major adverse cardiac events at 30 and 180 days. We retrospectively analyzed the HEART score of 1597 consecutive patients admitted to the Emergency Department of our Hospital for chest pain between January 1 and June 30, 2014. Of these, 190 did not meet the inclusion criteria and 29 were lost to follow-up. None of the 512 (37.2 %) patients with a low HEART score had an event within 180 days. The difference between the cumulative incidences of events in the three HEART score groups was statistically significant (P < 0.0001). We demonstrate that it might be possible to safely discharge Emergency Department chest pain patients with a low modified HEART score after an initial determination of high-sensitive troponin T, without a prolonged observation period or an additional cardiac testing.

Two-hour algorithm for triage toward rule-out and rule-in of acute myocardial infarction using high-sensitivity cardiac troponin T

BACKGROUND

High-sensitivity cardiac troponin (hs-cTn) may allow an earlier diagnosis of acute myocardial infarction (AMI).

METHODS

We prospectively enrolled 1148 (derivation cohort) and 517 (external validation cohort) unselected patients presenting with suspected AMI to the emergency department. Final diagnosis was adjudicated by 2 independent cardiologists. Hs-cTnT was measured at presentation and after 2 hours. A diagnostic algorithm incorporating hs-cTnT values at presentation and absolute changes within the first 2 hours was derived.

RESULTS

AMI was the final diagnosis in 16% of patients in the derivation and 9.1% in the validation cohort. The 2-hour algorithm developed in the derivation cohort classified 60% of patients as "rule-out," 16% as "rule-in," and 24% in the "observational-zone." Resulting sensitivity and negative predictive value (NPV) were 99.5% and 99.9%, respectively, for rule-out, and specificity and positive predictive value (PPV) were 96% and 78%, respectively, for rule-in. Applying the 2-hour triage algorithm in the external validation cohort, 78% of patients could be classified as "rule-out," 8% as "rule-in," and 14% in the "observational-zone." Resulting sensitivity and NPV were 96% and 99.5%, respectively, for rule-out, and specificity and PPV were 99% and 85%, respectively, for rule-in. Cumulative 30-day survival rates were 100%, 98.9%, and 95.2% (P < .001), and 100%, 100%, and 95% (P < .001) in patients classified as "rule-out," "observational-zone," and "rule-in" in the 2 cohorts, respectively.

CONCLUSIONS

A simple algorithm incorporating hs-cTnT baseline values and absolute changes over 2 hours allowed a triage toward safe rule-out, or accurate rule-in, of AMI in the vast majority of patients, with only 20% requiring more prolonged monitoring and serial blood sampling.