QT variability unrelated to RR variability during stress testing for identification of coronary artery disease

Stress test electrocardiogram (ECG) analysis is widely used for coronary artery disease (CAD) diagnosis despite its limited accuracy. Alterations in autonomic modulation of cardiac electrical activity have been reported in CAD patients during acute ischemia. We hypothesized that those alterations could be reflected in changes in ventricular repolarization dynamics during stress testing that could be measured through QT interval variability (QTV). However, QTV is largely dependent on RR interval variability (RRV), which might hinder intrinsic ventricular repolarization dynamics. In this study, we investigated whether different markers accounting for low-frequency (LF) oscillations of QTV unrelated to RRV during stress testing could be used to separate patients with and without CAD. Power spectral density of QTV unrelated to RRV was obtained based on time-frequency coherence estimation. Instantaneous LF power of QTV and QTV unrelated to RRV were obtained. LF power of QTV unrelated to RRV normalized by LF power of QTV was also studied. Stress test ECG of 100 patients were analysed. Patients referred to coronary angiography were classified into non-CAD or CAD group. LF oscillations in QTV did not show significant differences between CAD and non-CAD groups. However, LF oscillations in QTV unrelated to RRV were significantly higher in the CAD group as compared with the non-CAD group when measured during the first phases of exercise and last phases of recovery. ROC analysis of these indices revealed area under the curve values ranging from 61 to 73%. Binomial logistic regression analysis revealed LF power of QTV unrelated to RRV, both during the first phase of exercise and last phase of recovery, as independent predictors of CAD. In conclusion, this study highlights the importance of removing the influence of RRV when measuring QTV during stress testing for CAD identification and supports the added value of LF oscillations of QTV unrelated to RRV to diagnose CAD from the first minutes of exercise. This article is part of the theme issue ‘Advanced computation in cardiovascular physiology: new challenges and opportunities’.

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Abstract 251: Clinical Symptoms and Angiographic Findings of Patients Undergoing Percutaneous Coronary Intervention without Prior Stress Testing: Insights from the NCDR

Circulation Cardiovascular Quality and Outcomes ◽

10.1161/circoutcomes.5.suppl_1.a251 ◽

2012 ◽

Vol 5 (suppl_1) ◽

Author(s):

Mouin Abdallah ◽

John Spertus ◽

Nestor Mercado ◽

Brahmajee Nallamothu ◽

Kevin Kennedy ◽

...

Keyword(s):

Coronary Artery Disease ◽

Coronary Artery ◽

Stress Testing ◽

Diagnostic Yield ◽

Stress Test ◽

Test Group ◽

Coronary Intervention ◽

Percutaneous Coronary ◽

Artery Disease ◽

Prior Stress

Background: Many patients undergoing elective percutaneous coronary intervention (PCI) do not have prior stress testing. It is unknown if these patients have more severe angina or obstructive coronary artery disease (CAD), whereby proceeding directly to PCI would represent sound clinical judgment and efficient use of resources. Methods: We identified elective PCIs performed between 1/1/09 - 3/31/11 in the NCDR CathPCI Registry ® and assessed for differences in angina (CCS class) and severity of CAD in those with and without pre-procedural stress testing. To further understand whether proceeding to PCI without prior stress testing could be justified because of a high pre-test probability for obstructive CAD (e.g., >70% stenosis in an epicardial coronary artery), we evaluated cardiac catheterizations performed within the registry during the same period to assess the diagnostic yield of obstructive CAD in patients with and without prior stress testing. Results: Of 246,629 elective PCIs, 89,084 (36.1%) were performed without prior stress testing. A substantial proportion of both groups undergoing PCI were asymptomatic (no stress test group: 28.9% vs. stress test group: 30.7%), with only a modest difference in the frequency of CCS class III/IV angina (16.2% vs. 11.9%; Table). No meaningful differences in the frequency of proximal LAD (29.7 % vs. 29.9%), left main (5.6% vs. 7.2%) or 3-vessel coronary artery disease (21.1% vs. 19.5%) were observed in the 2 PCI groups. Moreover, the diagnostic yield for obstructive CAD on cardiac catheterization for patients without prior stress testing (n=462,611) was 35.4%, as compared with 58.0%, 38.8%, and 24.1% for those with severe, moderate, and mild ischemia, on pre-procedural stress testing. Conclusion: For elective PCI, the current practice of proceeding to coronary angiography and PCI without prior stress testing does not identify higher risk coronary anatomy or more symptomatic patients and may not improve diagnostic yield.

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Receiver operating characteristic (ROC) curves and the definition of threshold levels to diagnose coronary artery disease on electrocardiographic stress testing. Part II: The use of ROC curves in the choice of electrocardiographic stress test markers of ischaemia

Journal of Cardiovascular Medicine ◽

10.2459/jcm.0b013e32813ef418 ◽

2008 ◽

Vol 9 (1) ◽

pp. 22-31 ◽

Cited By ~ 6

Author(s):

Stefania Marazìa ◽

Luca Barnabei ◽

Raffaele De Caterina

Keyword(s):

Coronary Artery Disease ◽

Coronary Artery ◽

Receiver Operating Characteristic ◽

Stress Testing ◽

Operating Characteristic ◽

Stress Test ◽

Roc Curves ◽

Threshold Levels ◽

Artery Disease ◽

Definition Of

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Relationship of Stress Test Findings to Anatomic or Functional Extent of Coronary Artery Disease Assessed by Coronary Computed Tomography Angiography-Derived Fractional Flow Reserve

BioMed Research International ◽

10.1155/2021/6674144 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Demetrios Doukas ◽

Sorcha Allen ◽

Amy Wozniak ◽

Siri Kunchakarra ◽

Rina Verma ◽

...

Keyword(s):

Coronary Artery Disease ◽

Chest Pain ◽

Coronary Artery ◽

Stress Testing ◽

Stress Test ◽

Exercise Duration ◽

Fractional Flow ◽

Coronary Cta ◽

Flow Reserve ◽

Artery Disease

Background. In the United States, functional stress testing is the primary imaging modality for patients with stable symptoms suspected to represent coronary artery disease (CAD). Coronary computed tomography angiography (CTA) is excellent at identifying anatomic coronary artery disease (CAD). The application of computational fluid dynamics to coronary CTA allows fractional flow reserve (FFR) to be calculated noninvasively (FFRCT). The relationship of noninvasive stress testing to coronary CTA and FFRCT in real-world clinical practice has not been studied. Methods. We evaluated 206 consecutive patients at Loyola University Chicago with suspected CAD who underwent noninvasive stress testing followed by coronary CTA and FFRCT when indicated. Patients were categorized by stress test results (positive, negative, indeterminate, and equivocal). Duke treadmill score (DTS), METS, exercise duration, and chest pain with exercise were analyzed. Lesions ≥ 50 % stenosis were considered positive by coronary CTA. FF R CT < 0.80 was considered diagnostic of ischemia. Results. Two hundred and six patients had paired noninvasive stress test and coronary CTA/FFRCT results. The median time from stress test to coronary CTA was 49 days. Average patient age was 60.3 years, and 42% were male. Of the 206 stress tests, 75% were exercise (70% echocardiographic, 26% nuclear, and 4% EKG). There were no associations of stress test results with CAD > 50 % or FF R CT < 0.80 ( p = 0.927 and p = 0.910 , respectively). Of those with a positive stress test, only 30% (3/10) had CAD > 50 % and only 50% (5/10) had FF R CT < 0.80 . Chest pain with exercise did not correlate with CAD > 50 % or FF R CT < 0.80 ( p = 0.66 and p = 0.12 , respectively). There were no significant correlations between METS, DTS, or exercise duration and FFRCT ( r = 0.093 , p = 0.274 ; r = 0.012 , p = 0.883 ; and r = 0.034 , p = 0.680 ; respectively). Conclusion. Noninvasive stress testing, functional capacity, chest pain with exercise, and DTS are not associated with anatomic or functional CAD using a diagnostic strategy of coronary CTA and FFRCT.

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Abstract 1205: Patients without obstructive coronary artery disease and stress test results: An analysis from the National Cardiovascular Data Registry

Circulation ◽

10.1161/circ.118.suppl_18.s_1085-b ◽

2008 ◽

Vol 118 (suppl_18) ◽

Author(s):

Manesh R Patel ◽

Kevin J Anstrom ◽

Eric L Eisenstein ◽

Ralph G Brindis ◽

Eric D Peterson ◽

...

Keyword(s):

Coronary Artery Disease ◽

Coronary Artery ◽

Positive Predictive Value ◽

Stress Testing ◽

Stress Test ◽

Test Results ◽

Invasive Angiography ◽

Data Registry ◽

Artery Disease ◽

National Cardiovascular

Background: In stable patients without known coronary artery disease (CAD), clinical practice guidelines recommend documentation of ischemia prior to evaluation by invasive angiography. We sought to determine how often non-invasive stress testing is performed in this population and the association between stress test results and obstructive CAD. Methods: Patients undergoing cardiac catheterization for exclusion of CAD who were without prior history of myocardial infarction, PCI, or CABG were identified from 601 hospitals using the American College of Cardiology National Cardiovascular Data Registry between 2005 – 2007. Significant obstructive CAD was defined as the presence of any stenosis ≥ 50% left main or ≥ 70% major epicardial vessel. Patient demographics, risk factors, symptoms, stress test status and CAD presence were determined. Results: A total of 376,430 patients without known CAD were identified. The median age was 61 years, 53% were male, 26% had diabetes, and 69% had hypertension. At angiography, 142,912 (38%) of patients were found to have significant obstructive CAD. Symptom status was associated with the presence of CAD (stable angina 50%, atypical 25%, asymptomatic 40%; p<0.001). Stress testing was performed in 316,248 (84%) of patients prior to angiography, and results were associated with the presence of CAD (p<0.001) see Table . Although a positive stress test was noted in 255,617 (68% of patients undergoing cath), obstructive CAD was noted in only 105,435, yielding a positive predictive value of 41%. Conclusions: In a large national registry of stable patients without known CAD undergoing invasive angiography, only 38% were found to have significant obstructive disease. Although performed in 84% of patients prior to cath, the low positive predictive value of current stress tests may have contributed to the high rate of patients without obstructive CAD. Table p value for stress test results and presence of obstructive CAD p<0.001

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