Predictors of significant coronary artery disease in atrial fibrillation: Are cardiac troponins a useful measure

Alghamry, Alaa; Hanna, John; Pelecanos, Anita; Kyranis, S.; Khelgi, V.; O’Rourke, Peter; Carroll, Oran; Oxenford, Cassie; Rangaswamaiah, Swetha; Tan, Chee Eng

doi:10.1016/j.ijcard.2016.08.267

“…Other previous studies addressing the significance of troponin elevations in AF patients are to our knowledge all retrospective, use the older 4 th generation troponin assays and come to different conclusions [2,3,[26][27][28]. Some report an increased risk of MI and cardiac death during follow-up [2,3,27] while others fail to show that elevated troponin predicts significant CAD on angiography or 10 adverse cardiac events during follow-up [26,28]. Some of the reasons for this diversity may be different study populations and the use of different troponin assays with different cut offs (i.e.…”

Section: Discussionmentioning

confidence: 99%

Low risk patients with acute atrial fibrillation and elevated high-sensitivity troponin do not have increased incidence of pathological stress test: a prospective cohort study

Thelin

¹

,

Gerward

²

,

Melander³

2019

Preprint

0

View full text Add to dashboard Cite

Background Many patients with atrial fibrillation (AF) or atrial flutter (AFL) and rapid ventricular response (RVR) have elevated high-sensitivity troponin T (hsTnT) values. Elevated hsTnT is an independent risk marker for cardiovascular events and mortality. The aim was to examine if AF/AFL patients with RVR and elevated hsTnT have an increased incidence of pathological cardiac stress tests, indicating need of further evaluation for coronary artery disease (CAD). Methods We prospectively included 90 AF/AFL patients without known heart failure and CAD presenting with AF/AFL and RVR. Half of the patients had elevated hsTnT (cases) and half had levels below the 99th percentile (controls). All patients were discharged in sinus rhythm. After approximately one week in sinus rhythm a new hsTnT was analysed and the patients performed a bicycle exercise stress test within the 30 day follow-up. The primary endpoint was a pathological stress test confirmed by a pathological SPECT myocardial perfusion imaging or a coronary angiography. Results None of the controls reached the primary endpoint. Two patients (4%) out of the 45 cases reached the primary endpoint (p= 0.49 vs controls), but only one was found to have significant CAD at subsequent coronary angiography. Conclusions Patients with paroxysmal AF/AFL, without history of CAD and heart failure, who present with a RVR and minor hsTnT elevations do not have an increased incidence of pathological stress test compared to patients with hsTnT values below the 99th percentile.

show abstract

“…Other previous studies addressing the significance of troponin elevations in AF patients are to our knowledge all retrospective, use the older 4 th generation troponin assays and come to different conclusions [2,3,[26][27][28]. Some report an increased risk of MI and cardiac death during follow-up [2,3,27] while others fail to show that elevated troponin predicts significant CAD on angiography or adverse cardiac events during follow-up [26,28]. Some of the reasons for this diversity may be different study populations and the use of different troponin assays with different cut offs (i.e.…”

Section: Discussionmentioning

confidence: 99%

Low risk patients with acute atrial fibrillation and elevated high-sensitivity troponin do not have increased incidence of pathological stress test: a prospective cohort study

Thelin

¹

,

Gerward

²

,

Melander³

2019

Preprint

0

View full text Add to dashboard Cite

Background Many patients with atrial fibrillation (AF) or atrial flutter (AFL) and rapid ventricular response (RVR) have elevated high-sensitivity troponin T (hsTnT) values. Elevated hsTnT is an independent risk marker for cardiovascular events and mortality. The aim was to examine if AF/AFL patients with RVR and elevated hsTnT have an increased incidence of pathological cardiac stress tests, indicating need of further evaluation for coronary artery disease (CAD). Methods We prospectively included 90 AF/AFL patients without known heart failure and CAD presenting with AF/AFL and RVR. Half of the patients had elevated hsTnT (cases) and half had levels below the 99th percentile (controls). All patients were discharged in sinus rhythm. After approximately one week in sinus rhythm a new hsTnT was analysed and the patients performed a bicycle exercise stress test within the 30 day follow-up. The primary endpoint was a pathological stress test confirmed by a pathological SPECT myocardial perfusion imaging or a coronary angiography. Results None of the controls reached the primary endpoint. Two patients (4%) out of the 45 cases reached the primary endpoint (p= 0.49 vs controls), but only one was found to have significant CAD at subsequent coronary angiography. Conclusions Patients with paroxysmal AF/AFL, without history of CAD and heart failure, who present with a RVR and minor hsTnT elevations do not have an increased incidence of pathological stress test compared to patients with hsTnT values below the 99th percentile. Our results do not support the need of performing stress tests in this population.

show abstract

“…Alghamy et al [50] investigated the predictive value of elevated cTnI for severe coronary artery disease (sCAD) in patients presenting with atrial fibrillation (afib). They conducted a retrospective case-control study and found that troponin elevation above the 99 th percentile cut-off did not predict sCAD; however, elevatedcTnI was a strong indicator of sCAD especially if it exceeded 2.1 micrograms per liter [50]. Tachyarrhythmias should be considered a possible etiology of elevated troponins in patients presenting with elevated cardiac troponins who do not have ischemic risks factors or a clinical picture consistent with AMI.…”

Section: Arrhythmiasmentioning

confidence: 99%

“…Bakshi et al [12] noted that tachycardia was the cause of elevated troponins in 28% of patients without coronary artery disease as determined by lack of obstructive disease on left heart catheterization [12,49]. Alghamy et al [50] investigated the predictive value of elevated cTnI for severe coronary artery disease (sCAD) in patients presenting with atrial fibrillation (afib). They conducted a retrospective case-control study and found that troponin elevation above the 99 th percentile cut-off did not predict sCAD; however, elevatedcTnI was a strong indicator of sCAD especially if it exceeded 2.1 micrograms per liter [50].…”

Section: Arrhythmiasmentioning

confidence: 99%

A Review of Cardiac and Non-Cardiac Causes of Troponin Elevation and Clinical Relevance Part I: Cardiac Causes

2017

JCCR

View full text Add to dashboard Cite

IntroductionCardiac troponin T (cTnT) and troponin I (cTnI) are cardiac regulatory proteins that control the calcium mediated interaction between actin and myosin [1]. The troponin complex consists of three subunits: troponin C, troponin I, and troponin T. This complex is located on the myofibrillar thin (actin) filament of striated (skeletal and cardiac) muscle. The cardiac isoforms troponin T and I are only expressed in cardiac muscle [1].In the year 2007 a consensus statement from the Joint European Society of Cardiology and The American College of Cardiology committees redefined myocardial infarction (MI) as an elevation of cTnT or cTnI in conjunction with clinical evidence of myocardial ischemia [2]. They recommended highsensitivity cardiac troponin assays to rule out MI using a 3-hour pathway based on the 99 th percentile of the normal reference range [2]. Cardiac troponins are detected in the serum by the use of monoclonal antibodies to epitopes of cTnI and cTnT. These antibodies are highly specific for cardiac troponin but do not react with skeletal muscle troponins [3,4]. Troponin assays are quite sensitive and can detect <1 g of myocardial necrosis; therefore, the diagnosis of myocardial infarction requires that cTn must be above the 99 th percentile upper reference limit for the specific assay being used [5]. Some studies have reported that the 99 th percentile reference limit differs between men and women when measured with high-sensitivity assays for cardiac troponin [6].An elevation of cTn indicates the presence of, but not the underlying reason for, myocardial injury. Elevated troponins have been noted in several clinical conditions in addition to acute myocardial infarction (AMI). These conditions include pulmonary embolism, sepsis, heart failure, myocarditis, myocardial contusion, critical illness, cardio-toxic chemo, defibrillator shocks, atrial fibrillation, and end stage renal disease. Elevated cTnT and cTnI almost always imply a poor prognosis regardless of the mechanism by which troponins were released from cardiac myocytes into circulation. Ottani et al. found that the odds ratio for death and MI was 3.44-fold at 30 days in the cTnT-positive group compared to patients with unstable angina who did not have elevated troponins [7].The aim of this article is to highlight different conditions in which elevated troponins have been commonly noted, and to discuss the suggested mechanisms for elevated troponins in these patients. It is still unclear how to manage troponin elevation in clinical conditions other than AMI, but it is important to note the differential diagnosis for elevated troponins and the clinical significance of troponin elevation in each setting. Troponin elevation reflects acute or chronic myocardial damage but is not exclusive for ACS, thus causing some problems with interpretation of results. Differentiating elevated troponins due to non-coronary diseases is challenging; however, this differentiation is paramount in order to provide timely and appropriate treatment. This is a t...

show abstract

Predictors of significant coronary artery disease in atrial fibrillation: Are cardiac troponins a useful measure

Abstract: Background: Cardiac Troponin I (cTnI) is frequently measured in patients

Cited by 26 publications

References 40 publications

Low risk patients with acute atrial fibrillation and elevated high-sensitivity troponin do not have increased incidence of pathological stress test: a prospective cohort study

Low risk patients with acute atrial fibrillation and elevated high-sensitivity troponin do not have increased incidence of pathological stress test: a prospective cohort study

Low risk patients with acute atrial fibrillation and elevated high-sensitivity troponin do not have increased incidence of pathological stress test: a prospective cohort study

A Review of Cardiac and Non-Cardiac Causes of Troponin Elevation and Clinical Relevance Part I: Cardiac Causes

Contact Info

Product

Resources

About