Most preoperative stress tests fail to comply with practice guideline indications and do not reduce cardiac events

BACKGROUND

There is wide variation in stress test utilization before major vascular surgery and adherence to practice guidelines is unclear. We defined rates of stress test compliance at our institution and led a quality improvement initiative to improve compliance with American Heart Association (ACC/AHA) guidelines.

METHODS

We implemented a stress testing order set in the electronic medical record at one tertiary hospital. We reviewed all patients who underwent elective, major vascular surgery in the 6 months before (Jan 1, 2022 - Jul 1, 2022) and 6 months after (Aug 1, 2022 - Jan 31, 2023) implementation. We studied stress test guideline compliance, changes in medical or surgical management, and major adverse cardiac events (MACE).

RESULTS

Before order set implementation, 37/122 patients (30%) underwent stress testing within the past year (29 specifically ordered preoperatively) with 66% (19/29) guideline compliance. After order set implementation, 50/173 patients (29%) underwent stress testing within the past year (41 specifically ordered preoperatively) with 80% (33/41) guideline compliance. In the pre- and postimplementation cohorts, stress testing led to a cardiovascular medication change or preoperative coronary revascularization in 24% (7/29) and 27% (11/41) of patients, and a staged surgery or less invasive anesthetic strategy in 14% (4/29) and 4.9% (2/41) of patients, respectively. All unindicated stress tests were surgeon-ordered and none led to a change in management. There was no change in MACE after order set implementation.

CONCLUSIONS

Electronic medical record-based guidance of perioperative stress testing led to a slight decrease in overall stress testing and an increase in guideline-compliant testing. Our study highlights a need for improved preoperative cardiovascular risk assessment prior to major vascular surgery, which may eliminate unnecessary testing and more effectively guide perioperative decision-making.

Development and Validation of a Quantitative Coronary CT Angiography Model for Diagnosis of Vessel-Specific Coronary Ischemia

BACKGROUND

Noninvasive stress testing is commonly used for detection of coronary ischemia but possesses variable accuracy and may result in excessive health care costs.

OBJECTIVES

This study aimed to derive and validate an artificial intelligence-guided quantitative coronary computed tomography angiography (AI-QCT) model for the diagnosis of coronary ischemia that integrates atherosclerosis and vascular morphology measures (AI-QCTISCHEMIA) and to evaluate its prognostic utility for major adverse cardiovascular events (MACE).

METHODS

A post hoc analysis of the CREDENCE (Computed Tomographic Evaluation of Atherosclerotic Determinants of Myocardial Ischemia) and PACIFIC-1 (Comparison of Coronary Computed Tomography Angiography, Single Photon Emission Computed Tomography [SPECT], Positron Emission Tomography [PET], and Hybrid Imaging for Diagnosis of Ischemic Heart Disease Determined by Fractional Flow Reserve) studies was performed. In both studies, symptomatic patients with suspected stable coronary artery disease had prospectively undergone coronary computed tomography angiography (CTA), myocardial perfusion imaging (MPI), SPECT, or PET, fractional flow reserve by CT (FFRCT), and invasive coronary angiography in conjunction with invasive FFR measurements. The AI-QCTISCHEMIA model was developed in the derivation cohort of the CREDENCE study, and its diagnostic performance for coronary ischemia (FFR ≤0.80) was evaluated in the CREDENCE validation cohort and PACIFIC-1. Its prognostic value was investigated in PACIFIC-1.

RESULTS

In CREDENCE validation (n = 305, age 64.4 ± 9.8 years, 210 [69%] male), the diagnostic performance by area under the receiver-operating characteristics curve (AUC) on per-patient level was 0.80 (95% CI: 0.75-0.85) for AI-QCTISCHEMIA, 0.69 (95% CI: 0.63-0.74; P < 0.001) for FFRCT, and 0.65 (95% CI: 0.59-0.71; P < 0.001) for MPI. In PACIFIC-1 (n = 208, age 58.1 ± 8.7 years, 132 [63%] male), the AUCs were 0.85 (95% CI: 0.79-0.91) for AI-QCTISCHEMIA, 0.78 (95% CI: 0.72-0.84; P = 0.037) for FFRCT, 0.89 (95% CI: 0.84-0.93; P = 0.262) for PET, and 0.72 (95% CI: 0.67-0.78; P < 0.001) for SPECT. Adjusted for clinical risk factors and coronary CTA-determined obstructive stenosis, a positive AI-QCTISCHEMIA test was associated with an HR of 7.6 (95% CI: 1.2-47.0; P = 0.030) for MACE.

CONCLUSIONS

This newly developed coronary CTA-based ischemia model using coronary atherosclerosis and vascular morphology characteristics accurately diagnoses coronary ischemia by invasive FFR and provides robust prognostic utility for MACE beyond presence of stenosis.

Surveillance Stress Testing After Percutaneous Intervention for Patients With Multivessel or Left Main Coronary Disease

BACKGROUND

The optimal surveillance strategy after percutaneous coronary intervention (PCI) for high-risk patients with multivessel or left main coronary artery disease (CAD) remains uncertain.

OBJECTIVES

This study aims to determine the prognostic role of routine functional testing in patients with multivessel or left main CAD who underwent PCI.

METHODS

The POST-PCI (Pragmatic Trial Comparing Symptom-Oriented Versus Routine Stress Testing in High-Risk Patients Undergoing Percutaneous Coronary Intervention) trial randomized high-risk PCI patients to routine functional testing at 1 year or standard care alone during follow-up. This analysis focused on participants with multivessel or left main CAD. The primary outcome was a composite of death from any cause, myocardial infarction, or hospitalization for unstable angina at 2 years.

RESULTS

Among 1,706 initially randomized patients, 1,192 patients with multivessel (n = 833) or left main (n = 359) were identified, with 589 in the functional testing group and 603 in the standard care group. Two-year incidences of primary outcome were similar between the functional testing group and the standard care group (6.2% vs 5.7%, respectively; HR: 1.09; 95% CI: 0.68-1.74; P = 0.73). This trend persisted in both groups of multivessel (6.2% vs 5.7%; HR: 1.09; 95% CI: 0.62-1.89; P = 0.78) and left main disease (6.2% vs 5.7%; HR: 1.09; 95% CI: 0.46-2.56; P = 0.85) (P for interaction = 0.90). Routine surveillance functional testing was associated with increased rates of invasive angiography and repeat revascularization beyond 1 year.

CONCLUSIONS

In high-risk patients with multivessel or left main CAD who underwent PCI, there was no incremental clinical benefit from routine surveillance functional-testing compared with standard care alone during follow-up. (Pragmatic Trial Comparing Symptom-Oriented Versus Routine Stress Testing in High-Risk Patients Undergoing Percutaneous Coronary Intervention [POST-PCI]; NCT03217877).

AI-Based Fully Automated Left Atrioventricular Coupling Index as a Prognostic Marker in Patients Undergoing Stress CMR

BACKGROUND

The left atrioventricular coupling index (LACI) is a strong and independent predictor of heart failure (HF) in individuals without clinical cardiovascular disease. Its prognostic value is not established in patients with cardiovascular disease.

OBJECTIVES

This study sought to determine in patients undergoing stress cardiac magnetic resonance (CMR) whether fully automated artificial intelligence-based LACI can provide incremental prognostic value to predict HF.

METHODS

Between 2016 and 2018, the authors conducted a longitudinal study including all consecutive patients with abnormal (inducible ischemia or late gadolinium enhancement) vasodilator stress CMR. Control subjects with normal stress CMR were selected using propensity score matching. LACI was defined as the ratio of left atrial to left ventricular end-diastolic volumes. The primary outcome included hospitalization for acute HF or cardiovascular death. Cox regression was used to evaluate the association of LACI with the primary outcome after adjustment for traditional risk factors.

RESULTS

In 2,134 patients (65 ± 12 years, 77% men, 1:1 matched patients [1,067 with normal and 1,067 with abnormal CMR]), LACI was positively associated with the primary outcome (median follow-up: 5.2 years [IQR: 4.8-5.5 years]) before and after adjustment for risk factors in the overall propensity-matched population (adjusted HR: 1.18 [95% CI: 1.13-1.24]), in patients with abnormal CMR (adjusted HR per 0.1% increment: 1.22 [95% CI: 1.14-1.30]), and in patients with normal CMR (adjusted HR per 0.1% increment: 1.12 [95% CI: 1.05-1.20]) (all P < 0.001). After adjustment, a higher LACI of ≥25% showed the greatest improvement in model discrimination and reclassification over and above traditional risk factors and stress CMR findings (C-index improvement: 0.16; net reclassification improvement = 0.388; integrative discrimination index = 0.153, all P < 0.001; likelihood ratio test P < 0.001).

CONCLUSIONS

LACI is independently associated with hospitalization for HF and cardiovascular death in patients undergoing stress CMR, with an incremental prognostic value over traditional risk factors including inducible ischemia and late gadolinium enhancement.

Prognostic impact of artificial intelligence-based fully automated global circumferential strain in patients undergoing stress CMR

AIMS

To determine whether fully automated artificial intelligence-based global circumferential strain (GCS) assessed during vasodilator stress cardiovascular (CV) magnetic resonance (CMR) can provide incremental prognostic value.

METHODS AND RESULTS

Between 2016 and 2018, a longitudinal study included all consecutive patients with abnormal stress CMR defined by the presence of inducible ischaemia and/or late gadolinium enhancement. Control subjects with normal stress CMR were selected using a propensity score-matching. Stress-GCS was assessed using a fully automatic machine-learning algorithm based on featured-tracking imaging from short-axis cine images. The primary outcome was the occurrence of major adverse clinical events (MACE) defined as CV mortality or nonfatal myocardial infarction. Cox regressions evaluated the association between stress-GCS and the primary outcome after adjustment for traditional prognosticators. In 2152 patients [66 ± 12 years, 77% men, 1:1 matched patients (1076 with normal and 1076 with abnormal CMR)], stress-GCS was associated with MACE [median follow-up 5.2 (4.8-5.5) years] after adjustment for risk factors in the propensity-matched population [adjusted hazard ratio (HR), 1.12 (95% CI, 1.06-1.18)], and patients with normal CMR [adjusted HR, 1.35 (95% CI, 1.19-1.53), both P < 0.001], but not in patients with abnormal CMR (P = 0.058). In patients with normal CMR, an increased stress-GCS showed the best improvement in model discrimination and reclassification above traditional and stress CMR findings (C-statistic improvement: 0.14; NRI = 0.430; IDI = 0.089, all P < 0.001; LR-test P < 0.001).

CONCLUSION

Stress-GCS is not a predictor of MACE in patients with ischaemia, but has an incremental prognostic value in those with a normal CMR although the absolute event rate remains low.

Assessing Antigen-Adjuvant Complex Stability Against Physical Stresses By wNMR

This study applies an emerging analytical technology, wNMR (water proton nuclear magnetic resonance), to assess the stability of aluminum adjuvants and antigen-adjuvant complexes against physical stresses, including gravitation, flow and freeze/thaw. Results from wNMR are verified by conventional analytical technologies, including static light scattering and microfluidic imaging. The results show that wNMR can quickly and noninvasively determine whether an aluminum adjuvant or antigen-adjuvant complex sample has been altered by physical stresses.

Dobutamine stress echocardiography during transcatheter edge-to-edge mitral valve repair predicts residual mitral regurgitation

OBJECTIVES

The current study sought to determine whether low-dose dobutamine stress echocardiography (DSE) during transcatheter edge-to-edge mitral valve repair (TMVR) can predict residual mitral regurgitation (MR) at discharge.

BACKGROUND

In most patients, TMVR can successfully reduce MR from severe to mild or moderate. However, general anesthesia during the intervention affects hemodynamics and MR assessment. At discharge transthoracic echocardiogram residual MR (>moderate) is present in 10%-30% of patients which is associated with worse clinical outcome.

METHODS

In consecutive patients the severity of MR was determined at baseline, immediately after TMVR clip implantation and subsequently during low-dose DSE (both under general anesthesia) and at discharge.

RESULTS

A total of 39 patients were included (mean age 76.1 ± 8.1 years, 39% male, 56% functional MR, 41% left ventricular ejection fraction < 45%). An increase of MR during DSE was seen in 11 patients, of whom 6 (55%) showed >moderate MR at discharge. None of the 28 patients without an increase of MR during DSE showed >moderate MR at discharge. The diagnostic performance of the test could be established at a sensitivity of 100% and a specificity of 85% in unselected patients.

CONCLUSIONS

DSE during TMVR is a useful tool to predict residual MR at discharge. It could support procedural decision making, including implantation of additional clips and thus potentially improve clinical outcome.

Degradation pathways and impurity profiling of the anticancer drug apalutamide by HPLC and LC-MS/MS and separation of impurities using Design of Experiments

Apalutamide, an androgen receptor inhibitor, is used to treat prostate cancer. A stability-indicating high-performance liquid chromatography method was developed for the estimation of assay and organic impurities of apalutamide in drug substance and in tablet dosages using Design of Experiments. The chromatographic separation was achieved within 30 min using Atlantis dC₁₈ , 100 × 4.6 mm, 3.0 μm and the binary gradient program (10 mm KH₂ PO₄ , pH 3.5; acetonitrile). The detection wavelength, flow rate, column temperature and injection volume used were 270 nm, 1.0 ml/min, 45°C and 10 μl, respectively. The interaction of independent variables (pH, column temperature and flow rate) and their influences on HPLC parameters were studied using a central composite design, and then the peak separation and elution behaviors between apalutamide and its seven impurities were determined. The method validation was performed for linearity, detection limit, quantitation limit, accuracy, precision and robustness as per the International Conference on Harmonization. A high-quality recovery with good precision (91.7-106.0%) and correlations (r²  > 0.997) within a linear range of 0.12-2.24 μg/ml (0.05-0.3%, w/w) were achieved consistently for assay and organic impurities of apalutamide. The stability-indicating characteristics of the proposed method were assessed through forced degradation and mass balance studies. An effort was made to figure out the chemical structures of newly formed degradation products (DP1-DP5) using LC-MS/MS.

Safety, feasibility, and prognostic value of stress perfusion CMR in patients with MR-conditional pacemaker

AIMS

To assess the safety, feasibility, and prognostic value of stress cardiovascular magnetic resonance (CMR) in patients with pacemaker (PM).

METHODS AND RESULTS

Between 2008 and 2021, we conducted a bi-centre longitudinal study with all consecutive patients with MR-conditional PM referred for vasodilator stress CMR at 1.5 T in the Institut Cardiovasculaire Paris Sud and Lariboisiere University Hospital. They were followed for the occurrence of major adverse cardiovascular events (MACE) defined as cardiac death or non-fatal myocardial infarction. Cox regression analyses were performed to determine the prognostic value of CMR parameters. The quality of CMR was rated by two observers blinded to clinical details. Of 304 patients who completed the CMR protocol, 273 patients (70% male, mean age 71 ± 9 years) completed the follow-up (median [interquartile range], 7.1 [5.4-7.5] years). Among those, 32 experienced a MACE (11.7%). Stress CMR was well tolerated with no significant change in lead thresholds or pacing parameters. Overall, the image quality was rated good or excellent in 84.9% of segments. Ischaemia and late gadolinium enhancement (LGE) were significantly associated with the occurrence of MACE (hazard ratio, HR: 11.71 [95% CI: 4.60-28.2]; and HR: 5.62 [95% CI: 2.02-16.21], both P < 0.001). After adjustment for traditional risk factors, ischaemia and LGE were independent predictors of MACE (HR: 5.08 [95% CI: 2.58-14.0]; and HR: 2.28 [95% CI: 2.05-3.76]; both P < 0.001).

CONCLUSION

Stress CMR is safe, feasible and has a good discriminative prognostic value in consecutive patients with PM.

Ischemia With Nonobstructive Coronary Arteries: Insights From the ISCHEMIA Trial

BACKGROUND

Ischemia with nonobstructive coronary arteries (INOCA) is common clinically, particularly among women, but its prevalence among patients with at least moderate ischemia and the relationship between ischemia severity and non-obstructive atherosclerosis severity are unknown.

OBJECTIVES

The authors investigated predictors of INOCA in enrolled, nonrandomized participants in ISCHEMIA (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches), sex differences, and the relationship between ischemia and atherosclerosis in patients with INOCA.

METHODS

Core laboratories independently reviewed screening noninvasive stress test results (nuclear imaging, echocardiography, magnetic resonance imaging or nonimaging exercise tolerance testing), and coronary computed tomography angiography (CCTA), blinded to results of the screening test. INOCA was defined as all stenoses <50% on CCTA in a patient with moderate or severe ischemia on stress testing. INOCA patients, who were excluded from randomization, were compared with randomized participants with ≥50% stenosis in ≥1 vessel and moderate or severe ischemia.

RESULTS

Among 3,612 participants with core laboratory-confirmed moderate or severe ischemia and interpretable CCTA, 476 (13%) had INOCA. Patients with INOCA were younger, were predominantly female, and had fewer atherosclerosis risk factors. For each stress testing modality, the extent of ischemia tended to be less among patients with INOCA, particularly with nuclear imaging. There was no significant relationship between severity of ischemia and extent or severity of nonobstructive atherosclerosis on CCTA. On multivariable analysis, female sex was independently associated with INOCA (odds ratio: 4.2 [95% CI: 3.4-5.2]).

CONCLUSIONS

Among participants enrolled in ISCHEMIA with core laboratory-confirmed moderate or severe ischemia, the prevalence of INOCA was 13%. Severity of ischemia was not associated with severity of nonobstructive atherosclerosis. (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches [ISCHEMIA]; NCT01471522).

Environmental sustainability and financial stability: can macroprudential stress testing measure and mitigate climate-related systemic financial risk?

Despite widespread recognition among financial regulators and central banks that climate change may threaten financial stability, the causes and consequences of climate-related systemic financial risk remain underexplored. Stress testing has emerged as one of the most prevalent regulatory tools for addressing climate-related financial risks, and this article analyzes the role of stress testing in mitigating the effects of climate change on financial stability. Specifically, it synthesizes the multi-disciplinary literature on climate-related financial risk, financial stability, and stress testing to develop a framework for evaluating the capacity and effectiveness of stress tests for measuring and managing climate-related systemic financial risk. It then takes stock of climate stress testing proposals and early practices globally and applies the evaluative framework in comparative case studies of the Bank of England and US Federal Reserve. It concludes that stress testing can support the measurement and management of both microprudential and macroprudential climate-related financial risks, but the benefits of stress testing vis-à-vis climate change and financial stability are largely unrealized. Addressing the disconnect between climate stress testing policy motivation and implementation as well as the divergence between leading and lagging jurisdictions will require both interagency and international regulatory cooperation.

Machine-Learning Score Using Stress CMR for Death Prediction in Patients With Suspected or Known CAD

BACKGROUND

In patients with suspected or known coronary artery disease, traditional prognostic risk assessment is based on a limited selection of clinical and imaging findings. Machine learning (ML) methods can take into account a greater number and complexity of variables.

OBJECTIVES

This study sought to investigate the feasibility and accuracy of ML using stress cardiac magnetic resonance (CMR) and clinical data to predict 10-year all-cause mortality in patients with suspected or known coronary artery disease, and compared its performance with existing clinical or CMR scores.

METHODS

Between 2008 and 2018, a retrospective cohort study with a median follow-up of 6.0 (IQR: 5.0-8.0) years included all consecutive patients referred for stress CMR. Twenty-three clinical and 11 stress CMR parameters were evaluated. ML involved automated feature selection by random survival forest, model building with a multiple fractional polynomial algorithm, and 5 repetitions of 10-fold stratified cross-validation. The primary outcome was all-cause death based on the electronic National Death Registry. The external validation cohort of the ML score was performed in another center.

RESULTS

Of 31,752 consecutive patients (mean age: 63.7 ± 12.1 years, and 65.7% male), 2,679 (8.4%) died with 206,453 patient-years of follow-up. The ML score (ranging from 0 to 10 points) exhibited a higher area under the curve compared with Clinical and Stress Cardiac Magnetic Resonance score, European Systematic Coronary Risk Estimation score, QRISK3 score, Framingham Risk Score, and stress CMR data alone for prediction of 10-year all-cause mortality (ML score: 0.76 vs Clinical and Stress Cardiac Magnetic Resonance score: 0.68, European Systematic Coronary Risk Estimation score: 0.66, QRISK3 score: 0.64, Framingham Risk Score: 0.63, extent of inducible ischemia: 0.66, extent of late gadolinium enhancement: 0.65; all P < 0.001). The ML score also exhibited a good area under the curve in the external cohort (0.75).

CONCLUSIONS

The ML score including clinical and stress CMR data exhibited a higher prognostic value to predict 10-year death compared with all traditional clinical or CMR scores.

Major adverse cardiac events after emergency department evaluation of chest pain patients with advanced testing: Systematic review and meta-analysis

OBJECTIVES

Our primary objective was to describe the risk of major adverse cardiac events (MACE) at 1, 6, and 12 months after a negative coronary computed tomography angiogram (cCTA), electrocardiogram (ECG) stress test, stress echocardiography, and myocardial perfusion scintigraphy (MPS) in low- to intermediate-risk patients.

METHODS

Initially, 952 articles were identified for screening, 81 met criteria for full-text review, and once risk of bias was assessed, 33 articles were included in this meta-analysis. We utilized a random-effects model to assess pooled MACE event proportion for patients undergoing evaluation of acute coronary syndrome (ACS) when risk stratified to a low- to intermediate-risk category after undergoing standard testing. Heterogeneity analysis was performed using Cochrane's Q-test and I² statistic.

RESULTS

Twenty-one studies evaluated follow-up at 1 month with cCTA having a 0.09% (95% confidence interval [CI] = 0.03% to 0.26%) pooled MACE compared to 0.23% (95% CI = 0.01% to 5.8%) of the exercise stress testing (p = 1). MPS and cCTA had an overall event rate of 0.15% (95% CI = 0.06% to 0.41%) at 6 months (I²  = 0%). At 12 months, a subgroup analysis found a pooled cCTA MACE of 0.16% (95% CI = 0.04% to 0.65%) compared to 1.68% (95% CI = 0.01% to 2.6%) for stress echocardiography with low within-group heterogeneity (I²  = 0%). Subgroup analysis of cCTA with no disease versus nonobstructive disease (<50% stenosis) did not find statistical difference in the MACE at both 1 month (0.17% [95% CI = 0.04% to 0.67%] vs. 0.06% [95% CI = 0.01% to 0.34%]) and 12 months (0.44% [95% CI = 0.09% to 2.2% vs. 0.54% [95% CI = 0.19% to 1.5%]).

CONCLUSIONS

Patients presenting with chest pain who have a coronary CTA showing < 50% stenosis, negative ECG stress test, stress echocardiography, or stress myocardial perfusion scan in the past 12 months can be discharged without any further risk stratification if their ECG and troponin are reassuring given low MACE.

Cost-Minimization Analysis for Cardiac Revascularization in 12 Health Care Systems Based on the EuroCMR/SPINS Registries

OBJECTIVES

The aim of this study was to compare the costs of a noninvasive cardiac magnetic resonance (CMR)-guided strategy versus 2 invasive strategies with and without fractional flow reserve (FFR).

BACKGROUND

Coronary artery disease (CAD) is a major contributor to the public health burden. Stress perfusion CMR has excellent accuracy to detect CAD. International guidelines recommend as a first step noninvasive testing of patients in stable condition with known or suspected CAD. However, nonadherence in routine clinical practice is high.

METHODS

In the EuroCMR (European Cardiovascular Magnetic Resonance) registry (n = 3,647, 59 centers, 18 countries) and the U.S.-based SPINS (Stress-CMR Perfusion Imaging in the United States) registry (n = 2,349, 13 centers, 11 states), costs were calculated for 12 health care systems (8 in Europe, the United States, 2 in Latin America, and 1 in Asia). Costs included diagnostic examinations (CMR and x-ray coronary angiography [CXA] with and without FFR), revascularizations, and complications during 1-year follow-up. Seven subgroup analyses covered low- to high-risk cohorts. Patients with ischemia-positive CMR underwent CXA and revascularization at the treating physician's discretion (CMR+CXA strategy). In the hypothetical invasive CXA+FFR strategy, costs were calculated for initial CXA and FFR in vessels with ≥50% stenoses, assuming the same proportion of revascularizations and complications as with the CMR+CXA strategy and FFR-positive rates as given in the published research. In the CXA-only strategy, costs included CXA and revascularizations of ≥50% stenoses.

RESULTS

Consistent cost savings were observed for the CMR+CXA strategy compared with the CXA+FFR strategy in all 12 health care systems, ranging from 42% ± 20% and 52% ± 15% in low-risk EuroCMR and SPINS patients with atypical chest pain, respectively, to 31% ± 16% in high-risk SPINS patients with known CAD (P < 0.0001 vs 0 in all groups). Cost savings were even higher compared with CXA only, at 63% ± 11%, 73% ± 6%, and 52% ± 9%, respectively (P < 0.0001 vs 0 in all groups).

CONCLUSIONS

In 12 health care systems, a CMR+CXA strategy yielded consistent moderate to high cost savings compared with a hypothetical CXA+FFR strategy over the entire spectrum of risk. Cost savings were consistently high compared with CXA only for all risk groups.

Variability in Coronary Artery Disease Testing for Patients With New-Onset Heart Failure

BACKGROUND

Coronary artery disease (CAD) is the most common cause of new-onset heart failure (HF). Although guidelines recommend ischemic evaluation in this population, testing has historically been underutilized.

OBJECTIVES

This study aimed to identify contemporary trends in CAD testing for patients with new-onset HF, particularly after publication of the STICHES (Surgical Treatment for Ischemic Heart Failure Extension Study), and to characterize geographic and clinician-level variability in testing patterns.

METHODS

We determined the proportion of patients with incident HF who received CAD testing from 2004 to 2019 using an administrative claims database covering commercial insurance and Medicare. We identified demographic and clinical predictors of CAD testing during the 90 days before and after initial diagnosis. Patients were grouped by their county of residence to assess national variation. Patients were then linked to their primary care physician and/or cardiologist to evaluate variation across clinicians.

RESULTS

Among 558,322 patients with new-onset HF, 34.8% underwent CAD testing and 9.3% underwent revascularization. After multivariable adjustment, patients who underwent CAD testing were more likely to be younger, male, diagnosed in an acute care setting, and have systolic dysfunction or recent cardiogenic shock. Incidence of CAD testing remained flat without significant change post-STICHES. Covariate-adjusted testing rates varied from 20% to 45% across counties. The likelihood of testing was higher among patients co-managed by a cardiologist (adjusted OR: 5.12; 95% CI: 4.98-5.27) but varied substantially across cardiologists (IQR: 50.9%-62.4%).

CONCLUSIONS

Most patients with new-onset HF across inpatient and outpatient settings did not receive timely testing for CAD. Substantial variability in testing persists across regions and clinicians.

Predictors of Left Main Coronary Artery Disease in the ISCHEMIA Trial

BACKGROUND

Detection of ≥50% diameter stenosis left main coronary artery disease (LMD) has prognostic and therapeutic implications. Noninvasive stress imaging or an exercise tolerance test (ETT) are the most common methods to detect obstructive coronary artery disease, though stress test markers of LMD remain ill-defined.

OBJECTIVES

The authors sought to identify markers of LMD as detected on coronary computed tomography angiography (CTA), using clinical and stress testing parameters.

METHODS

This was a post hoc analysis of ISCHEMIA (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches), including randomized and nonrandomized participants who had locally determined moderate or severe ischemia on nonimaging ETT, stress nuclear myocardial perfusion imaging, or stress echocardiography followed by CTA to exclude LMD. Stress tests were read by core laboratories. Prior coronary artery bypass grafting was an exclusion. In a stepped multivariate model, the authors identified predictors of LMD, first without and then with stress testing parameters.

RESULTS

Among 5,146 participants (mean age 63 years, 74% male), 414 (8%) had LMD. Predictors of LMD were older age (P < 0.001), male sex (P < 0.01), absence of prior myocardial infarction (P < 0.009), transient ischemic dilation of the left ventricle on stress echocardiography (P = 0.05), magnitude of ST-segment depression on ETT (P = 0.004), and peak metabolic equivalents achieved on ETT (P = 0.001). The models were weakly predictive of LMD (C-index 0.643 and 0.684).

CONCLUSIONS

In patients with moderate or severe ischemia, clinical and stress testing parameters were weakly predictive of LMD on CTA. For most patients with moderate or severe ischemia, anatomical imaging is needed to rule out LMD. (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches [ISCHEMIA]; NCT01471522).

Triaging Down the 2021 Chest Pain Guidelines

We applied the 2021 AHA/ACC/ASE/CHEST/SAEM/SCCT/SCMR chest pain guidelines to a case of a 76-year-old woman with no known coronary disease presenting to the emergency department with acute chest pain and an intermediate probability of acute coronary syndrome. Her workup per the guidelines involved rapid electrocardiogram, high-sensitivity troponins, nuclear stress testing, and eventually coronary invasive angiography. (Level of Difficulty: Advanced.)

Cardiovascular Disease in Women Update: Ischemia, Diagnostic Testing, and Menopause Hormone Therapy

OBJECTIVE

This update will address 3 areas specifically that are essential to improving cardiovascular outcomes for women.

METHODS

The current literature has been reviewed and three important areas of cardiovascular care in women are highlighted. First is that even though women and men share many traditional risk factors for ischemic heart disease, several of these risk factors affect women disproportionately when it comes to CVD risk and events. There are also unique sex-specific risk factors for women and risk factors that are more common in women than in men. Adverse outcomes of pregnancy and hypertensive disorders of pregnancy are associated with an increased long-term risk of CVD and events. At menopause, cardiovascular risks increase, and lipids become unfavorable. Second is that diagnostic testing for ischemic heart disease presents different specificities and sensitivities between men and women and testing should be determined according to what is best and safest for women. Third is that currently, menopause hormone therapy is approved by the U.S. Food and Drug Administration for the treatment of vasomotor and genitourinary symptoms, prevention of osteoporosis, and estrogen replacement in the setting of surgical menopause, hypogonadism, or premature ovarian insufficiency. It is not recommended for the primary or secondary prevention of CVD and not recommended for women with high atherosclerotic CVD risk.

RESULTS

Cardiovascular disease (CVD) remains the most common cause of death in women in the United States despite tremendous improvements in cardiovascular care for men and women. The prevention of CVD in women with early detection and implementation of preventive therapies before atherosclerotic CVD develops is critical to improving outcomes for women.

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'.

Cardiovascular Evaluation of Liver Transplant Patients by Using Coronary Calcium Scoring in ECG-Synchronized Computed Tomographic Scans

Background: The goal of cardiac evaluation of patients awaiting orthotopic liver transplantation (OLT) is to identify the patients at risk for cardiovascular events (CVEs) in the peri- and postoperative periods by opportunistic evaluation of coronary artery calcium (CAC) in non-gated abdominal computed tomographs (CT). Methods: We hypothesized that in patients with OLT, a combination of Lee’s revised cardiac index (RCRI) and CAC scoring would improve diagnostic accuracy and prognostic impact compared to non-invasive cardiac testing. Therefore, we retrospectively evaluated 169 patients and compared prediction of CVEs by both methods. Results: Standard workup identified 22 patients with a high risk for CVEs during the transplant period, leading to coronary interventions. Eighteen patients had a CVE after transplant and a CAC score > 0. The combination of CAC and RCRI ≥ 2 had better negative (NPV) and positive predictive values (PPV) for CVEs (NPV 95.7%, PPV 81.6%) than standard non-invasive stress tests (NPV 92.0%, PPV 54.5%). Conclusion: The cutoff value of CAC > 0 by non-gated CTs combined with RCRI ≥ 2 is highly sensitive for identifying patients at risk for CVEs in the OLT population.

Long-term prognostic value of ischaemia and cardiovascular magnetic resonance-related revascularization for stable coronary disease, irrespective of patient's sex: a large retrospective study

AIMS

To assess the sex-specific, long-term prognostic value of myocardial ischaemia induced by stress cardiovascular magnetic resonance (CMR) and early CMR-related revascularization in consecutive patients from a large registry.

METHODS AND RESULTS

Between 2008 and 2010, all consecutive patients referred for stress CMR were followed for the occurrence of major adverse cardiovascular events (MACE), defined by cardiovascular mortality or recurrent non-fatal myocardial infarction (MI). Early CMR-related revascularization was defined as any revascularization within 90 days after CMR. Among 3664 patients (56.9% male, mean age 69.9 ± 11.8 years), 472 (12.9%) had MACE (163 women and 309 men) after a median follow-up of 8.8 (IQR 6.9-9.5) years. Inducible ischaemia and late gadolinium enhancement (LGE) by CMR were associated with MACE in women and men (all P < 0.001). In multivariable Cox regression, inducible ischaemia, LGE, and CMR-related revascularization were independent predictors of MACE both in women [heart rate (HR) 4.79, 95% confidence interval (CI) 2.17-9.10; HR 1.82, 95% CI 1.22-2.71; HR 0.71, 95% CI 0.54-0.92, respectively; all P < 0.001] and men (HR 3.88, 95% CI 2.33-5.98; HR 1.48, 95% CI 1.16-1.89; HR 0.78, 95% CI 0.65-0.97, respectively; all P < 0.001). The addition of CMR-parameters led to improved model discrimination for MACE (C-statistic 0.61 vs. 0.71; NRI = 0.212; IDI = 0.032) for both women and men. CMR-related revascularization was associated with a lower incidence of MACE in patients with left ventricular ejection fraction (LVEF)<50%.

CONCLUSION

Inducible ischaemia and early CMR-related revascularization were good long-term predictors of MACE irrespective of sex. CMR-related revascularization was associated with a lower MACE incidence in the sole sub-set of patients with LVEF < 50%.

Long-Term Prognostic Value of Stress CMR in Patients With Heart Failure and Preserved Ejection Fraction

OBJECTIVES

The objectives of this study were to investigate the long-term prognostic value of inducible myocardial ischemia assessed by vasodilator stress cardiovascular magnetic resonance (CMR) in patients with HFpEF.

BACKGROUND

Some studies suggest that ischemia could play a key role in HF in patients with preserved ejection fraction (HFpEF).

METHODS

Between 2008 and 2019, consecutive patients prospectively referred for stress CMR with HFpEF as defined by current guidelines, without known coronary artery disease (CAD), were followed for the occurrence of major adverse cardiovascular events (MACE), as defined by cardiovascular mortality or nonfatal myocardial infarction (MI). Secondary composite outcomes included cardiovascular mortality or hospitalization for acute HF. Cox regression analysis was performed to determine the prognostic value of inducible ischemia or late gadolinium enhancement (LGE) by CMR.

RESULTS

Among the 1,203 patients with HFpEF (73 ± 13 years of age; 29% males) who underwent stress CMR and completed follow-up (6.9 years interquartile range [IQR]: 6.7 to 7.7 years]), 108 experienced a MACE (9%). Kaplan-Meier analysis showed inducible ischemia and LGE were significantly associated with MACE (HR: 6.63; 95% confidence interval [CI]: 4.54 to 9.69; and HR: 2.56; 95% CI: 1.60 to 4.09, respectively; both p < 0.001) and secondary outcomes (HR: 8.40; 95% CI: 6.31 to 11.20; p < 0.001; and HR: 1.87; 95% CI: 1.27 to 2.76, respectively; p = 0.002). In multivariate analysis, inducible ischemia and LGE were independent predictors of MACE (HR: 6.10; 95% CI: 4.14 to 9.00; p < 0.001 and HR: 1.62; 95% CI: 1.06 to 2.49; p = 0.039; respectively).

CONCLUSIONS

Stress CMR-inducible myocardial ischemia and LGE have accurate discriminative long-term prognostic value in HFpEF patients without known CAD to predict the occurrence of MACE.

Prognostic value of dipyridamole stress perfusion cardiovascular magnetic resonance in elderly patients >75 years with suspected coronary artery disease

AIMS

There are only very few data on the prognostic value of stress cardiovascular magnetic resonance (CMR) in elderly people, while life expectancy of the general population is steadily increasing. Therefore, this study aims to assess the prognostic value of vasodilator stress perfusion CMR in elderly >75 years.

METHODS AND RESULTS

Between 2008 and 2017, we included consecutive elderly >75 years without known coronary artery disease (CAD) referred for dipyridamole stress CMR. They were followed for the occurrence of major adverse cardiovascular events (MACE) including cardiac death or non-fatal myocardial infarction. Univariate and multivariate analyses were performed to determine the prognostic value of ischaemia or late gadolinium enhancement. Of 754 elderly individuals (82.0 ± 3.9 years, 48.4% men), 659 (87.4%) completed the follow-up with median follow-up of 4.7 years. Using Kaplan-Meier analysis, the presence of myocardial ischaemia was associated with the occurrence of MACE [hazard ratio (HR) 5.38, 95% confidence interval (CI): 3.56-9.56; P < 0.001]. In a multivariable Cox regression including clinical characteristics and CMR indexes, inducible ischaemia was an independent predictor of a higher incidence of MACE (HR 4.44, 95% CI: 2.51-7.86; P < 0.001). In patients without ischaemia, the occurrence of MACE was lower in women when compared with men (P < 0.01).

CONCLUSION

Stress CMR is safe and has discriminative prognostic value in elderly, with a significantly lower event rate of future cardiovascular event or death in subjects without ischaemia or infarction.

Impurity profiling and stability-indicating method development and validation for the estimation of assay and degradation impurities of midostaurin in softgel capsules using HPLC and LC-MS

Midostaurin (MDS) is used for the treatment of acute myeloid leukemia, myelodysplastic syndrome, and advanced systemic mastocytosis. MDS softgel capsule samples were subjected to stress testing per International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use guidelines for impurity profiling study. MDS underwent extensive degradation under stress testing (acid, alkaline, oxidative, photolytic, thermolytic, and hydrolysis conditions) and formed four degradation products (DPs). MDS and its DPs were separated well from one another with good resolution using reserved-phase HPLC using an Inertsil ODS-3V column (250 × 4.6 mm, 5 μm) and a mobile phase of ammonium formate (40 mM) and acetonitrile. The stability-indicating characteristic of the newly developed method was proven for the estimation of MDS assay, and its organic impurities were free from interference. The validated method exhibited excellent linearity, accuracy, precision, specificity, detection limit, and quantitation limit within 25 min run time. Stress testing, robustness, and solution stability were performed to ensure the continuous performance of the developed method. The peak fractions of DPs formed under stress testing were isolated and characterized using LC-MS, ¹ H and ¹³ C NMR, IR, and UV-Vis. The structure of the major DPs was predicted as DP1 based on the spectral data. The proposed method is effectively used for MDS in bulk drug and finished formulations in the pharmaceutical industry.

EACVI survey on investigations and imaging modalities in chronic coronary syndromes

Aims

The European Association of Cardiovascular Imaging (EACVI) Scientific Initiatives Committee performed a global survey to evaluate current practice for the assessment and management of patients with suspected and confirmed chronic coronary syndromes.

Methods and results

One-hundred and ten imaging centres from 37 countries across the world responded to the survey. Most non-invasive investigations for coronary artery disease were widely available, except cardiovascular magnetic resonance (available 40% centres). Coronary computed tomography angiography (CCTA) and nuclear scans were reported by a multi-disciplinary team in only a quarter of centres. In the initial assessment of patients presenting with chest pain, only 32% of respondents indicated that they rely on pre-test probability for selecting the optimal imaging test while 31% proceed directly to CCTA. In patients with established coronary artery disease and recurrent chest pain, respondents opted for stress echocardiography (27%) and nuclear stress perfusion scans (26%). In asymptomatic patients with coronary artery disease and an obstructive (>70%) right coronary artery stenosis, 58% of respondents were happy to pursue medical therapy without further testing or intervention. This proportion fell to 29% with left anterior descending artery stenosis and 1% with left main stem obstruction. In asymptomatic patients with evidence of moderate-to-severe myocardial ischaemia (15%), only 18% of respondents would continue medical therapy without further investigation.

Conclusion

Despite guidelines recommendations pre-test probability is used to assess patients with suspected coronary artery in a minority of centres, one-third of centres moving directly to CCTA. Clinicians remain reticent to pursue a strategy of optimal medical therapy without further investigation or intervention in patients with controlled symptoms but obstructive coronary artery stenoses or myocardial ischaemia.

Prognostic Value of Vasodilator Stress Perfusion Cardiovascular Magnetic Resonance in Patients With Prior Myocardial Infarction

OBJECTIVES

This study sought to assess the incremental prognostic value of vasodilator stress cardiovascular magnetic resonance (CMR) in patients with prior myocardial infarction (MI).

BACKGROUND

Recurrent MI is a major cause of mortality and morbidity among MI survivors.

METHODS

Between 2008 and 2019, consecutive patients with prior MI referred for stress CMR were followed up for the occurrence of major adverse cardiovascular events (MACE), defined by cardiovascular mortality or recurrent nonfatal MI. Uni- and multivariable Cox regressions were performed to determine the prognostic value of inducible ischemia and the extent of myocardial scar.

RESULTS

Among 1,594 patients with prior MI and myocardial scar on CMR, 1,401 (92%) (68.2 ± 11.0 years; 61.4% men) completed the follow-up (median: 6.2 years), and 205 had MACE (14.6%). Patients without inducible ischemia experienced a lower annual rate of MACE (3.1%) than those with 1-2 (4.9%), 3-5 (21.5%), or ≥6 segments of ischemia (45.7%) (all p < 0.01). Using Kaplan-Meier analysis, the presence of inducible ischemia and the extent of scar were associated with MACE (hazard ratio [HR]:3.52; 95% confidence interval [CI]: 2.67 to 4.65 and HR: 1.66; 95% CI: 1.53 to 2.18, respectively; both p < 0.001). In multivariable stepwise Cox regression, the presence of ischemia and the extent of scar were independent predictors of MACE (HR: 2.84; 95% CI: 2.14 to 3.78 and HR: 1.57; 95% CI: 1.44 to 1.72, respectively; both p < 0.001). These findings were significant in both symptomatic and asymptomatic patients. The addition of CMR parameters to the model including traditional risk factors resulted in a better discrimination for MACE (C-statistic: 0.76 vs. 0.62).

CONCLUSIONS

In patients with prior MI, vasodilator stress CMR has independent and incremental prognostic value over traditional risk factors.

What Is the Clinical Impact of Stress CMR After the ISCHEMIA Trial?

After progressively receding for decades, cardiovascular mortality due to coronary artery disease has recently increased, and the associated healthcare costs are projected to double by 2030. While the 2019 European Society of Cardiology guidelines for chronic coronary syndromes recommend non-invasive cardiac imaging for patients with suspected coronary artery disease, the impact of non-invasive imaging strategies to guide initial coronary revascularization and improve long-term outcomes is still under debate. Recently, the ISCHEMIA trial has highlighted the fundamental role of optimized medical therapy and the lack of overall benefit of early invasive strategies at a median follow-up of 3.2 years. However, sub-group analyses excluding procedural infarctions with longer follow-ups of up to 5 years have suggested that patients undergoing revascularization had better outcomes than those receiving medical therapy alone. A recent sub-study of ISCHEMIA in patients with heart failure or reduced left ventricular ejection fraction (LVEF <45%) indicated that revascularization improved clinical outcomes compared to medical therapy alone. Furthermore, other large observational studies have suggested a favorable prognostic impact of coronary revascularization in patients with severe inducible ischemia assessed by stress cardiovascular magnetic resonance (CMR). Indeed, some data suggest that stress CMR-guided revascularization assessing the extent of the ischemia could be useful in identifying patients who would most benefit from invasive procedures such as myocardial revascularization. Interestingly, the MR-INFORM trial has recently shown that a first-line stress CMR-based non-invasive assessment was non-inferior in terms of outcomes, with a lower incidence of coronary revascularization compared to an initial invasive approach guided by fractional flow reserve in patients with stable angina. In the present review, we will discuss the current state-of-the-art data on the prognostic value of stress CMR assessment of myocardial ischemia in light of the ISCHEMIA trial results, highlighting meaningful sub-analyses, and still unanswered opportunities of this pivotal study. We will also review the available evidence for the potential clinical application of quantifying the extent of ischemia to stratify cardiovascular risk and to best guide invasive and non-invasive treatment strategies.

Seroprevalence of SARS-CoV-2 Antibody in Echocardiography and Stress Laboratory

PURPOSE

Transesophageal echocardiography is an aerosol-generating procedure, and exercise stress testing is a potentially aerosol-generating activity. Concern has been raised about heightened risk of transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among health care personnel participating in these procedures. We aimed to investigate the prevalence of past coronavirus disease 2019 (COVID-19) infection in echocardiography and stress laboratory staff.

METHODS

All staff who worked in the echocardiography and stress laboratories of one high-traffic urban hospital from March 15, 2020, to June 15, 2020, were asked to voluntarily participate. Those willing to participate were consented, and past COVID-19 infection was confirmed by a SARS-CoV-2 IgG antibody test (ARCHITECT, Abbott Laboratories) from June 15, 2020, to July 3, 2020. Clinical data were collected from the electronic medical record, and self-reported symptoms were documented with a participant survey.

RESULTS

A total of 43 staff members (86.0% of 50 total laboratory staff) participated. A majority of participants were less than 40 years old (69.8%), were White (86.0%), and were women (79.1%); mean body mass index was 24.9 ± 4.7 kg/m². Of the 43 staff members tested for past COVID-19 infection, 3 (7.0%) had a positive SARS-CoV-2 IgG antibody result. There were no unique features in the 3 SARS-CoV-2 antibody-positive subjects; of these, 2 had known prior COVID-19 infection and 1 was asymptomatic.

CONCLUSIONS

This study provides clinical data on the seroprevalence of SARS-CoV-2 antibody in echocardiography and stress laboratory staff who regularly participate in a variety of procedures that are or may be aerosol-generating.

Cardiovascular Biomarkers and Imaging in Older Adults: JACC Council Perspectives

Whereas the burgeoning population of older adults is intrinsically vulnerable to cardiovascular disease, the utility of many management precepts that were validated in younger adults is often unclear. Whereas biomarker- and imaging-based tests are a major part of cardiovascular disease care, basic assumptions about their use and efficacy cannot be simply extrapolated to many older adults. Biology, physiology, and body composition change with aging, with important influences on cardiovascular disease testing procedures and their interpretation. Furthermore, clinical priorities of older adults are more heterogeneous, potentially undercutting the utility of testing data that are collected. The American College of Cardiology and the National Institutes on Aging, in collaboration with the American Geriatrics Society, convened, at the American College of Cardiology Heart House, a 2-day multidisciplinary workshop, "Diagnostic Testing in Older Adults with Cardiovascular Disease," to address these issues. This review summarizes key concepts, clinical limitations, and important opportunities for research.

Prognostic value of vasodilator stress perfusion CMR in patients with previous coronary artery bypass graft

AIMS 

The accuracy and prognostic value of stress perfusion cardiac magnetic resonance (CMR) are established in coronary artery disease (CAD) patients. Because myocardial contrast kinetics may be altered after coronary artery bypass graft (CABG), most studies excluded CABG patients. This study aimed to assess the prognostic value of vasodilator stress perfusion CMR in CABG patients.

METHODS AND RESULTS 

Consecutive CABG patients referred for stress CMR were retrospectively included and followed for the occurrence of major adverse cardiovascular events (MACE) including cardiovascular (CV) death or non-fatal myocardial infarction (MI). Cox regression analyses were performed to determine the prognostic association of inducible ischaemia and late gadolinium enhancement (LGE) by CMR. Of 866 consecutive CABG patients, 852 underwent the stress CMR protocol and 771 (89%) completed the follow-up [median (interquartile range) 4.2 (3.3-6.2) years]. There were 85 MACE (63 CV deaths and 22 non-fatal MI). Using Kaplan-Meier analysis, the presence of inducible ischaemia identified the occurrence of MACE [hazard ratio (HR) 3.52, 95% confidence interval (CI): 2.27-5.48; P < 0.001] and CV death (HR 2.55, 95% CI: 1.52-4.25; P < 0.001). In a multivariable stepwise Cox regression including clinical characteristics and CMR indexes, the presence of inducible ischaemia was an independent predictor of a higher incidence of MACE (HR 3.22, 95% CI: 2.06-5.02; P < 0.001) and CV death (HR 2.15, 95% CI: 1.28-3.62; P = 0.003), and the same was observed for LGE (both P = 0.02).

CONCLUSION 

Stress CMR has a good discriminative prognostic value in patients after CABG, with a higher incidence of MACE and CV death in patients with inducible ischaemia and/or LGE.

Feasibility and Prognostic Value of Vasodilator Stress Perfusion CMR in Patients With Atrial Fibrillation

OBJECTIVES

The aim of this study was to assess the feasibility and prognostic value of vasodilator stress perfusion cardiovascular magnetic resonance (CMR) in patients with atrial fibrillation (AF).

BACKGROUND

Because most studies have excluded arrhythmic patients, the prognostic value of stress perfusion CMR in patients with AF is unknown.

METHODS

Between 2008 and 2018, consecutive patients with suspected or stable chronic coronary artery disease and AF referred for vasodilator stress perfusion CMR were included and followed for the occurrence of major adverse cardiovascular event(s) (MACE), defined as cardiovascular death or nonfatal myocardial infarction. The diagnosis of AF was defined by 12-lead electrocardiography before and after CMR. Univariate and multivariate Cox regressions were performed to determine the prognostic value of inducible ischemia or late gadolinium enhancement (LGE) by CMR.

RESULTS

Of 639 patients (mean age 72 ± 9 years, 77% men), 602 (94%) completed the CMR protocol, and 538 (89%) completed follow-up (median 5.1 years); 80 had MACE. Using Kaplan-Meier analysis, the presence of ischemia (hazard ratio [HR]: 7.56; 95% confidence interval [CI]: 4.86 to 11.80) or LGE (HR: 2.41; 95% CI: 1.55 to 3.74) was associated with the occurrence of MACE (p < 0.001 for both). In a multivariate Cox regression including clinical and CMR indexes, the presence of ischemia (HR: 5.98; 95% CI: 3.68 to 9.73) or LGE (HR: 2.61; 95% CI: 1.89 to 3.60) was an independent predictor of MACE (p < 0.001 for both).

CONCLUSIONS

In patients with AF, stress perfusion CMR is feasible and has good discriminative prognostic value to predict the occurrence of MACE.

Mortality in Patients With Right Bundle-Branch Block in the Absence of Cardiovascular Disease

Background Right bundle-branch block (RBBB) occurs in 0.2% to 1.3% of people and is considered a benign finding. However, some studies have suggested increased risk of cardiovascular morbidity and mortality. We sought to evaluate risk attributable to incidental RBBB in patients without prior diagnosis of cardiovascular disease (CVD). Methods and Results We reviewed the Mayo Clinic Integrated Stress Center database for exercise stress tests performed from 1993 to 2010. Patients with no known CVD-defined as absence of coronary disease, structural heart disease, heart failure, or cerebrovascular disease-were selected. Only Minnesota residents were included, all of whom had full mortality and outcomes data. There were 22 806 patients without CVD identified; 220 of whom (0.96%) had RBBB, followed for 6 to 23 years (mean 12.4±5.1). There were 8256 women (36.2%), mean age was 52±11 years; and 1837 deaths (8.05%), including 645 cardiovascular-related deaths (2.83%), occurred over follow-up. RBBB was predictive of all-cause (hazard ratio [HR], 1.5; 95% CI, 1.1-2.0; P=0.0058) and cardiovascular-related mortality (HR,1.7; 95% CI, 1.1-2.8; P=0.0178) after adjusting for age, sex, diabetes mellitus, hypertension, obesity, current and past history of smoking, and use of a heart rate-lowering drug. Patients with RBBB exhibited more hypertension (34.1% versus 23.7%, P<0.0003), decreased functional aerobic capacity (82±25% versus 90±24%; P<0.0001), slower heart rate recovery (13.5±11.5 versus 17.1±9.4 bpm; P<0.0001), and more dyspnea (28.2% versus 22.4%; P<0.0399) on exercise testing. Conclusions Patients with RBBB without CVD have increased risk of all-cause mortality, cardiovascular-related mortality, and lower exercise tolerance. These data suggest RBBB may be a marker of early CVD and merit further prospective evaluation.

High-Sensitivity Cardiac Troponin After Cardiac Stress Test: A Systematic Review and Meta-Analysis

Background The recent introduction of high-sensitivity cardiac troponin (hs-cTn) assays has allowed clinicians to measure hs-cTn before and after cardiac stress testing, but the hs-cTn release pattern and potential utility in identifying inducible myocardial ischemia are unclear. We thus conducted a systematic review and meta-analysis to improve our understanding of hs-cTn release associated with exercise and pharmacological stress testing. Methods and Results Studies published between January 2008 and July 2016 that reported hs-cTn change values (high-sensitivity cardiac troponin T [hs-cTnT] or high-sensitivity cardiac troponin I [hs-cTnI]) in relation to cardiac stress testing were searched and reviewed by 2 independent screeners. Primary outcomes were pooled estimates of absolute and relative hs-cTn changes after cardiac stress test, stratified by the presence of inducible myocardial ischemia. This meta-analysis included 11 studies (n=2432 patients). After exercise stress testing, hs-cTnT increased by 0.5 ng/L or 11% (6 studies, n=406) and hs-cTnI by 2.4 ng/L or 41% (4 studies, n=365) in patients with inducible myocardial ischemia versus hs-cTnT by 1.1 ng/L or 18% (8 studies, n=629; P=0.29) and hs-cTnI by 1.8 ng/L or 72% (4 studies, n=831; P=0.61) in patients who did not develop inducible myocardial ischemia. After pharmacological stress test, hs-cTnT changed by -0.1 ng/L or -0.4% (6 studies, n=251) and hs-cTnI by 2.4 ng/L or 32% (2 studies, n=108) in patients with inducible myocardial ischemia versus hs-cTnT by 0.7 ng/L or 11% (5 studies, n=443, P=0.44) and hs-cTnI by 1.7 ng/L or 38% (2 studies, n=116; P=0.62) in patients who did not develop inducible myocardial ischemia. Conclusions hs-cTn rising patterns after exercise and pharmacological stress testing appear inconsistent and comparably small, and do not appear to be correlated with inducible myocardial ischemia.

On the Stability and Degradation Pathways of Venetoclax under Stress Conditions

Venetoclax is an orally bioavailable, B-cell lymphoma-2 (BCL-2) selective inhibitor, used for the treatment of various types of blood cancers, such as chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL). In this study we investigated the degradation of venetoclax under various stress conditions including acidic, basic, oxidative, photolytic and thermolytic conditions. We isolated and identified six of its main degradation products produced in forced degradation studies. The structures of the isolated degradation products were determined by using nuclear magnetic resonance (NMR) spectroscopy, high resolution mass spectrometry (HRMS) and infrared (IR) spectroscopy. Additionally, one oxidation degradation product was identified with comparison to a commercially obtained venetoclax impurity. We proposed the key degradation pathways of venetoclax in solution. To the best of our knowledge, no structures of degradation products of venetoclax have been previously published. The study provides novel and primary knowledge of the stability characteristics of venetoclax under stress conditions. Venetoclax is currently the only BCL-2 protein inhibitor on the market. In addition to single agent treatment, it is effective in combinational therapy, so future drug development involving venetoclax can be expected. A better insight into the stability properties of the therapeutic can facilitate future studies involving venetoclax and aid in the search of new similar therapeutics.

Feasibility and accuracy of SPECT myocardial perfusion imaging in end-stage lung disease

BACKGROUND

Coronary artery disease (CAD) is associated with increased mortality in patients with chronic lung disease. However, non-invasive diagnostic of CAD is difficult, especially in patients with more advanced disease. Therefore, we aimed to assess the feasibility and accuracy of SPECT-myocardial perfusion imaging (MPI) stress testing with regadenoson in patients with end-stage lung disease (ELD) undergoing assessment of stable CAD.

METHODS

Between January 2012 and May 2018, 102 patients with ELD, who were referred to our institution for lung transplant evaluation, were assessed retrospectively. All patients underwent both stress SPECT-MPI as well as coronary angiography.

RESULTS

The mean age in our population was 57±6 years. All patients had severe pulmonary function impairment. During stress SPECT-MPI 14 patients (14%) reported regadenoson-related symptoms, but only 2 patients (2%) required medical treatment. Coronary angiography revealed obstructive CAD in 20 patients (20%). Among those, 5 patients had abnormal SPECT-MPI and PCI was performed in 3 patients accordingly. In 14 patients with obstructive CAD, revascularization was deferred based on normal SPECT-MPI findings.

CONCLUSIONS

SPECT-MPI using regadenoson is well tolerated in patients with ELD and can help to make decisions about coronary revascularization before lung transplant.

What do stress tests test? Experimentation, demonstration, and the sociotechnical performance of regulatory science

After their successful introduction during the 2007-2009 financial crisis, central bank stress tests were adopted as a fixture of international banking supervision. However, in recent years a new normal has emerged where banks are expected to pass the tests, raising questions about the tests' usefulness and legitimacy. Combining a dramaturgical interpretation of regulatory science with the idea of performativity in the sociology of finance, this article understands stress tests as a sociotechnical Goffmanian performance. With a focus on the Bank of England's program, the paper argues that the Bank's decision to make their tests "predictable" is an attempt to shore up central bank legitimacy by constraining regulatory discretion. This is accomplished through the use of calculative and procedural stage management techniques which allow the Bank to control the contingency of the testing process while demonstrating its objectivity. Nevertheless, the conclusion suggests that in the context of low levels of trust in central banks, routine declarations of "all clear" may undermine public confidence in the tests' credibility and necessity. The study draws on 20 interviews with high-level regulators, financial practitioners and other stakeholders in the Bank of England's stress tests.

Considerations for Stress Testing Performed in Conjunction with Myocardial Perfusion Imaging

For myocardial perfusion imaging (MPI), the best test to evaluate hemodynamic changes during stress is an exercise treadmill test. It provides independent prognostic value, including evaluation of total exercise time, performance, and capacity; heart rate response during exercise, with ischemia, and in recovery; blood pressure response; myocardial oxygen demand; and assessment of symptoms. Combining these exercise data with perfusion imaging provides the best prognostic value and risk stratification for patients. Although exercise stress testing accompanied by MPI is preferential, it is not always possible since an increasing number of patients cannot exercise to a maximal (symptom-limited) level. Further, there is much evidence in the literature demonstrating a suboptimal, non-symptom-limited (not achieving at least 4-6 min or <85% of maximum predicted heart rate) exercise test performed as part of an MPI study may result in a false-negative outcome. Therefore, pharmacologic stress agents provide an excellent alternative for those patients who cannot achieve an adequate heart rate response or adequately perform physical exercise. This article focuses on considerations for performing stress (exercise and pharmacologic) testing in conjunction with MPI. It is meant to provide a basic overview of the principles of exercise stress testing; discuss the indications, contraindications, patient preparation, and protocols for exercise stress testing; discuss the contraindications, administration protocols, and side effects for vasodilator (adenosine, dipyridamole, and regadenoson) stress testing; and discuss the contraindications, administration protocols, and side effects for dobutamine stress testing.

Unsupervised clustering for phenotypic stratification of clinical, demographic, and stress attributes of cardiac risk in patients with nonischemic exercise stress echocardiography

INTRODUCTION AND AIM

Patients undergoing exercise echocardiography with no evidence of myocardial ischemia are considered a low-risk group; however, this group is likely heterogeneous in terms of short-term adverse events and subsequent cardiac testing. We hypothesized that unsupervised cluster modeling using clinical and stress characteristics can detect heterogeneity in cardiovascular risk and need for subsequent cardiac testing among these patients.

METHODS

We retrospectively studied 445 patients who had exercise echocardiography results negative for myocardial ischemia. All patients were followed for adverse cardiovascular events, subsequent cardiac testing, and nonacute coronary syndrome (ACS) revascularization. The heterogeneity of the study subjects was tested using computational clustering, an exploratory statistical method designed to uncover invisible natural groups within data. Clinical and stress predictors of adverse events were extracted and used to construct 3 unsupervised cluster models: clinical, stress, and combined. The study population was split into training (357 patients) and testing sets (88 patients).

RESULTS

In the training set, the clinical, stress, and combined cluster models yielded 5, 4, and 3 clusters, respectively. Each model had 1 high-risk and 1 low-risk cluster while other clusters were intermediate. The combined model showed a better predictive ability compared to the clinical or stress models alone. The need for future testing mirrored the pattern of adverse cardiovascular events. A risk score derived from the combined cluster model predicted end points with acceptable accuracy. The patterns of risk and the calculated risk scores were preserved in the testing set.

CONCLUSIONS

Patients with no evidence of ischemia on exercise stress echocardiography represent a heterogeneous group. Cluster-based modeling using combined clinical and stress characteristics can expose this heterogeneity. The findings can help better risk-stratify this group of patients and aid cost-effective healthcare utilization toward better diagnostics and therapeutics.

Stress Testing Versus CT Angiography in Patients With Diabetes and Suspected Coronary Artery Disease

BACKGROUND

The optimal noninvasive test (NIT) for patients with diabetes and stable symptoms of coronary artery disease (CAD) is unknown.

OBJECTIVES

The purpose of this study was to assess whether a diagnostic strategy based on coronary computed tomographic angiography (CTA) is superior to functional stress testing in reducing adverse cardiovascular (CV) outcomes (CV death or myocardial infarction [MI]) among symptomatic patients with diabetes.

METHODS

PROMISE (Prospective Multicenter Imaging Study for Evaluation of Chest Pain) was a randomized trial evaluating an initial strategy of CTA versus functional testing in stable outpatients with symptoms suggestive of CAD. The study compared CV outcomes in patients with diabetes (n = 1,908 [21%]) and without diabetes (n = 7,058 [79%]) based on their randomization to CTA or functional testing.

RESULTS

Patients with diabetes (vs. without) were similar in age (median 61 years vs. 60 years) and sex (female 54% vs. 52%) but had a greater burden of CV comorbidities. Patients with diabetes who underwent CTA had a lower risk of CV death/MI compared with functional stress testing (CTA: 1.1% [10 of 936] vs. stress testing: 2.6% [25 of 972]; adjusted hazard ratio: 0.38; 95% confidence interval: 0.18 to 0.79; p = 0.01). There was no significant difference in nondiabetic patients (CTA: 1.4% [50 of 3,564] vs. stress testing: 1.3% [45 of 3,494]; adjusted hazard ratio: 1.03; 95% confidence interval: 0.69 to 1.54; p = 0.887; interaction term for diabetes p value = 0.02).

CONCLUSIONS

In diabetic patients presenting with stable chest pain, a CTA strategy resulted in fewer adverse CV outcomes than a functional testing strategy. CTA may be considered as the initial diagnostic strategy in this subgroup. (PROspective Multicenter Imaging Study for Evaluation of Chest Pain [PROMISE]; NCT01174550).

A Novel Testing Approach for Oxidative Degradation Dependent Incompatibility of Amine Moiety Containing Drugs with PEGs in Solid-State

Reactive impurities originating from excipients can cause drug stability issues, even at trace amounts. When produced during final dosage form storage, they are especially hard to control, and often, factors inducing their formation remain unidentified. Oxidative degradation dependent formation of formaldehyde and formic acid is responsible for N-methylation and N-formylation of amine-moiety-containing drug substances. A very popular combination of polyethylene glycols and iron oxides, used in more than two-thirds of FDA-approved tablet formulation drugs in 2018, was found to be responsible for increased concentrations of N-methyl impurity in the case of paroxetine hydrochloride. We propose a novel testing approach for early identification of potentially problematic combinations of excipients and drug substances. The polyethylene glycol 6000 degradation mechanism and kinetics in the presence of iron oxides is studied. The generality of the proposed stress test setup in view of the susceptibility of amine-moiety-containing drug substances to N-methylation and N-formylation is evaluated.