Hypertension as One of the Main Non-Myocardial Infarction-Related Causes of Increased Cardiospecific Troponins: From Mechanisms to Significance in Current Medical Practice

It is well known that many pathological conditions of both cardiovascular diseases (CVDs) (coronary heart disease, myocardial infarction, arrhythmias, myocarditis, cardiomyopathy, etc.) and non-cardiac (sepsis, anemia, kidney diseases, diabetes mellitus, etc.) origin in the course of their development cause injury to contractile cardiac muscle cells - myocardial cells (MCs). One of the most sensitive and specific criteria for detecting MC injury are cardiospecific troponins (CTs), which are regulatory protein molecules that are released into the blood serum from MC upon their death or injury. Current methods for determining CTs are called high-sensitive ones, and their main advantage is a very low minimum detectable concentration (limit of detection) (average 1 - 10 ng/L or less), which allows early detection of minor MC injury at the earliest stages of CVDs, and therefore they can change the understanding of disease development mechanisms and open up new diagnostic possibilities. One of the most common and dangerous early diseases of the cardiovascular system is hypertension (HT). The novelty of this article lies in the discussion of a new diagnostic direction - predicting the risk of developing CVDs and their dangerous complications in patients with HT by determining the concentration of CTs. In addition, pathophysiological mechanisms underlying MC injury and the release of CTs into the bloodstream and the elimination of CTs into the urine are proposed. This information will contribute to additional fundamental and clinical research to verify the new diagnostic possibility of using CTs in clinical practice (for the management of patients with HT).

Highly sensitive detection of SARS-CoV-2 RNA by multiplex rRT-PCR for molecular diagnosis of COVID-19 by clinical laboratories

BACKGROUND

The detection of SARS-CoV-2 RNA by real-time reverse transcription-polymerase chain reaction (rRT-PCR) is used to confirm the clinical diagnosis of COVID-19 by molecular diagnostic laboratories. We developed a multiplex rRT-PCR methodology for the detection of SARS-CoV-2 RNA.

METHODS

Three genes were used for multiplex rRT-PCR: the Sarbecovirus specific E gene, the SARS-CoV-2 specific N gene, and the human ABL1 gene as an internal control.

RESULTS

Good correlation of C_q values was observed between the simplex and multiplex rRT-PCR methodologies. Low copies (<25 copies/reaction) of SARS-CoV-2 RNA were detected by the novel multiplex rRT-PCR method.

CONCLUSION

The proposed multiplex rRT-PCR methodology will enable highly sensitive detection of SARS-CoV-2 RNA, reducing reagent use and cost, and time required by clinical laboratory technicians.

Elevated serum cardiac troponin and mortality in acute pulmonary embolism: Systematic review and meta-analysis

OBJECTIVES

To evaluate whether elevated levels of cardiac troponin increases the risk of mortality in patients with acute PE.

METHODS

We conducted a systematic review and meta-analysis with rigorous statistical evaluation using publications (2000-2018) from Cochrane Library, MEDLINE, PubMed, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), WHO International Clinical Trials Registry Platform, and Google Scholar databases. We searched for retrospective, prospective, and randomized controlled trials (RCT) or quasi-RCT studies that assessed the effect of elevated troponin versus normal levels on the outcomes of PE. The main outcome of interest was all-cause mortality. Extracted data included authors, the origin of studies, source population, study settings and duration, inclusion/exclusion criteria, data sources and measurement, sample size, and mortality. Data heterogeneity was assessed using the Cochrane Q homogeneity test with a significance set at p < 0.10. If the studies were statistically homogeneous, a fixed effect model was selected.

RESULTS

Out of 1825 references, 46 analytical studies were included with a total of 10842 patients with PE. The effect of elevated troponin on mortality had a pooled odd ratio (OR) of 4.33 for all studies, 3.7for HsTnT, 14.81 for HsTnI, 7.85 for cTnT, 2.81 for cTnI, 9.02 for low-risk PE and 4.80 for 90-day mortality. The pooled negative likelihood ratios for all-cause mortality using HsTnI, cTnI and cTnT assay were 0.21, 0.33 and 0.65, respectively.

CONCLUSION

Regardless of the troponin assay, pooled analysis indicates that elevated troponin is significantly associated with higher mortality in patients with PE.