Troponin I/ejection fraction ratio: A new index to differentiate Takotsubo cardiomyopathy from myocardial infarction

Comparison of troponin and natriuretic peptides in Takotsubo syndrome and acute coronary syndrome: a meta-analysis

OBJECTIVE

Takotsubo syndrome (TTS) is an acute heart failure syndrome which resembles acute coronary syndrome (ACS) at presentation. Differentiation requires coronary angiography, but where this does not occur immediately, cardiac biomarkers may provide additional utility. We performed a meta-analysis to compare troponin and natriuretic peptides (NPs) in TTS and ACS to determine if differences in biomarker profile can aid diagnosis.

METHODS

We searched five literature databases for studies reporting NPs (Brain NP (BNP)/NT-pro-BNP) or troponin I/T in TTS and ACS, identifying 28 studies for troponin/NPs (5618 and 1145 patients, respectively).

RESULTS

Troponin was significantly lower in TTS than ACS (standardised mean difference (SMD) -0.86; 95% CI, -1.08 to -0.64; p<0.00001), with an absolute difference of 75 times the upper limit of normal (×ULN) higher in ACS than TTS. Conversely, NPs were significantly higher in TTS (SMD 0.62; 95% CI, 0.44 to 0.80; p<0.00001) and 5.8×ULN greater absolutely. Area under the curve (AUC) for troponin in ACS versus TTS was 0.82 (95% CI, 0.70 to 0.93), and 0.92 (95% CI, 0.80 to 1.00) for ST-segment elevation myocardial infarction versus TTS. For NPs, AUC was 0.69 (95% CI, 0.48 to 0.89). Combination of troponin and NPs with logistic regression did not improve AUC. Recursive Partitioning and Regression Tree analysis calculated a troponin threshold ≥26×ULN that identified 95% cases as ACS where and specificity for ACS were 85.71% and 53.57%, respectively, with 94.32% positive predictive value and 29.40% negative predictive value.

CONCLUSIONS

Troponin is lower and NPs higher in TTS versus ACS. Troponin had greater power than NPs at discriminating TTS and ACS, and with troponin ≥26×ULN patients are far more likely to have ACS.

Cardiovascular Biomarkers: Lessons of the Past and Prospects for the Future

Cardiovascular diseases (CVDs) are a major healthcare burden on the population worldwide. Early detection of this disease is important in prevention and treatment to minimise morbidity and mortality. Biomarkers are a critical tool to either diagnose, screen, or provide prognostic information for pathological conditions. This review discusses the historical cardiac biomarkers used to detect these conditions, discussing their application and their limitations. Identification of new biomarkers have since replaced these and are now in use in routine clinical practice, but still do not detect all disease. Future cardiac biomarkers are showing promise in early studies, but further studies are required to show their value in improving detection of CVD above the current biomarkers. Additionally, the analytical platforms that would allow them to be adopted in healthcare are yet to be established. There is also the need to identify whether these biomarkers can be used for diagnostic, prognostic, or screening purposes, which will impact their implementation in routine clinical practice.

MFGE8, ALB, APOB, APOE, SAA1, A2M, and C3 as Novel Biomarkers for Stress Cardiomyopathy

BACKGROUND

Stress cardiomyopathy (SCM) is a transient reversible left ventricular dysfunction that more often occurs in women. Symptoms of SCM patients are similar to those of acute coronary syndrome (ACS), but little is known about biomarkers. The goals of this study were to identify the potentially crucial genes and pathways associated with SCM.

METHODS

We analyzed microarray datasets GSE95368 derived from the Gene Expression Omnibus (GEO) database. Firstly, identify the differentially expressed genes (DEGs) between SCM patients in normal patients. Then, the DEGs were used for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Finally, the protein-protein interaction (PPI) network was constructed and Cytoscape was used to find the key genes.

RESULTS

In total, 25 DEGs were identified, including 10 upregulated genes and 15 downregulated genes. These DEGs were mainly enriched in ECM-receptor interaction, dilated cardiomyopathy (DCM), human papillomavirus infection, and focal adhesion, whereas in GO function classification, they were mainly enriched in the extracellular region, positive regulation of the multicellular organismal process, establishment of localization, and intracellular vesicle.

CONCLUSION

Seven hub genes contained APOE, MFGE8, ALB, APOB, SAA1, A2M, and C3 identified as hub genes of SCM, which might be used as diagnostic biomarkers or molecular targets for the treatment of SCM.

Stress cardiomyopathy of the critically ill: Spectrum of secondary, global, probable and subclinical forms

Stress cardiomyopathy (SC) typically presents as potential acute coronary syndrome (ACS) in previously healthy people. While there may be physical or mental stressors, the initial symptom is usually chest pain. This form conforms to the published Mayo diagnostic criteria, is well reported and as the presentation is initially cardiac, is considered primary SC. Increasingly we see SC develop several days into the hospitalization secondary to medical or surgical critical illness. This condition is more complex, presents atypically, is not easy to recognize and carries a much worse prognosis. Label of Secondary SC is appropriate as it manifests in sicker hospitalized patients with numerous comorbidities. We review the limited but provocative literature pertinent to SC in the critically ill and describe important clues to identify global, subclinical and probable forms of SC. We illustrate the several unique clinical features, demographic differences and propose a diagnostic algorithm to optimize cardiac care in the critically ill.

Application of Cardiac Troponin in Cardiovascular Diseases Other Than Acute Coronary Syndrome

BACKGROUND

Increased cardiac troponin concentrations in acute coronary syndrome (ACS) identify patients with ongoing cardiomyocyte necrosis who are at increased risk. However, with the use of more precise assays, cardiac troponin increases are commonly noted in other cardiovascular conditions as well. This has generated interest in the use of cardiac troponin for prognostic assessment and clinical management of these patients. In this review, we have summarized the data from studies investigating the implications of cardiac troponin concentrations in various acute and chronic conditions beyond ACS, i.e., heart failure, myocarditis, Takotsubo cardiomyopathy, aortic dissection, supraventricular arrhythmias, valve disease, pulmonary arterial hypertension, stroke, and in the perioperative setting.

CONTENT

Cardiac troponin concentrations are often detectable and frankly increased in non-ACS conditions, in particular when measured with high-sensitivity (hs) assays. With the exception of myocarditis and Takotsubo cardiomyopathy, cardiac troponin concentrations carry strong prognostic information, mainly with respect to mortality, or incipient and/or worsening heart failure. Studies investigating the prognostic benefit associated with cardiac troponin–guided treatments however, are almost lacking and the potential role of cardiac troponin in the management of non-ACS conditions is not defined.

SUMMARY

Increased cardiac troponin indicates increased risk for adverse outcome in patients with various cardiovascular conditions beyond ACS. Routine measurement of cardiac troponin concentrations can however, not be generally recommended unless there is a suspicion of ACS. Nonetheless, any finding of an increased cardiac troponin concentration in a patient without ACS should at least prompt the search for possible underlying conditions and these should be managed meticulously according to current guidelines to improve outcome.

Simple markers can distinguish Takotsubo cardiomyopathy from ST segment elevation myocardial infarction

BACKGROUND

Takotsubo cardiomyopathy (TTC) is a clinical condition mimicking acute myocardial infarction. A specific biomarker for TTC screening is required, but until now, no single biomarker has been established for the early diagnosis of TTC and differentiation from ST-segment elevation myocardial infarction (STEMI). In our study we focused on the simple markers that are available in every hospital.

METHODS

In 66 consecutive patients (pts) who were hospitalized with TTC and 66 pts with STEMI, cardiac biomarkers, such as NT-proBNP, TnI, CK and CKMB mass were determined during 12h from admission and compared with demographic, clinical and echocardiographic findings.

RESULTS

The concentration of NTproBNP was greater in pts with TTC than STEMI (4702pg/ml vs 2138pg/ml). The concentration of TnI and CKMB mass was greater in the STEMI group than in the TTC group (TnI: 2.1ng/ml and CK MB mass: 9.5ng/ml in pts with TTC vs TnI: 19ng/ml and CK MB mass: 73.3ng/ml in pts with STEMI). The NTproBNP/TnI ratio and NTproBNP/CKMB mass ratio were, respectively, 2235.2 and 678.2 in pts with TTC and 81.6 and 27.5 in pts with STEMI (p<0.001). Moreover, the NTproBNP/EF ratio was also statistically significant (110.4 in TTC group and 39.4 in STEMI group).

CONCLUSIONS

NTproBNP/TnI, NTproBNP/CKMB mass and NTproBNP/EF ratios can distinguish TTC from STEMI at an early stadium. The most accurate marker is the NTproBNP/TnI ratio.

Myocardial infarction, symptomatic third degree atrioventricular block and pulmonary embolism caused by thalidomide: a case report

Background

Thalidomide has been reported to cause numerous thromboembolic events. Deep vein thrombosis and pulmonary embolism are more common. It can also cause bradycardia and even total atrioventricular block. Rarely, it causes coronary artery spasm and even myocardial infarction. But almost simultaneous onset of myocardial infarction, third degree atrioventricular block and pulmonary embolism in one patient has not been reported so far.

Case presentation

A 53-year old man presented because of chest pain, nausea and then syncope for several minutes. Previous medical history included neurodermitis for which thalidomide was given and hypercholesterolemia with simvastatin taking. The patient didn’t exhibit any other established risk factors for coronary artery disease. Electrocardiography showed sinus rhythm with third degree atrioventricular block and complete right bundle branch block, and precordial leads ST segment elevation. The diagnosis of acute coronary syndrome was suspected, but further coronary angiography demonstrated no flow-limiting lesions in coronary arteries, and temporary pacemaker was implanted. After admission, low SpO₂ and elevated D-dimer level was mentioned. Further computed tomography pulmonary angiography revealed pulmonary embolism. Thalidomide was thought to be the cause of hypercoagulability and coronary spasm, so it was ceased immediately. Therapeutic low molecule weight heparin was initiated and then switched to warfarin with appropriate INR, and nifedipine was described for coronary spasm. The patient’s symptoms completely relived and SpO₂ recovered, and atrioventricular block had disappeared during hospitalization with pacemaker removed.

Conclusion

This is the very first case in which myocardial infarction, third degree atrioventricular block and pulmonary embolism almost simultaneously developed. We should be ware that anti-thrombotic prophylaxis, which needs further investigation for optimal drug and dosage, may be beneficial in thalidomide therapy. And it is also important to monitor patients taking thalidomide for signs and symptoms of bradycardia or higher degree atrioventricular block.