Mechanisms and diagnostic evaluation of persistent or recurrent angina following percutaneous coronary revascularization

Persistence or recurrence of angina after a percutaneous coronary intervention (PCI) may affect about 20-40% of patients during short-medium-term follow-up. This appears to be true even when PCI is 'optimized' using physiology-guided approaches and drug-eluting stents. Importantly, persistent or recurrent angina post-PCI is associated with a significant economic burden. Healthcare costs may be almost two-fold higher among patients with persistent or recurrent angina post-PCI vs. those who become symptom-free. However, practice guideline recommendations regarding the management of patients with angina post-PCI are unclear. Gaps in evidence into the mechanisms of post-PCI angina are relevant, and more research seems warranted. The purpose of this document is to review potential mechanisms for the persistence or recurrence of angina post-PCI, propose a practical diagnostic algorithm, and summarize current knowledge gaps.

Association between ceramides and coronary artery stenosis in patients with coronary artery disease

BACKGROUND

Coronary artery stenosis induces heart diseases including acute coronary syndrome (ACS). Some studies reported the ceramide species are associated with the ACS and major adverse cardia and cerebrovascular events (MACE). However, few studies investigated the association between plasma ceramide levels and the severity of stenosis, together with the onset of diseases. This aim of the present study was to investigate the association betweencertain ceramide species, coronary artery stenosis and acute coronary syndrome.

METHODS

Five hundred fifty-three patients with definite or suspected CAD were recruited and received angiography. Subjects were assigned into 4 groups according to the severity of coronary artery stenosis. The measurements of 4 plasma ceramide species, namely, Cer (d18:1/16:0), Cer (d18:1/18:0), Cer (d18:1/24:1), Cer (d18:1/24:0) were carried out by Liquid chromatography-tandem mass spectrometry (LC-MS/MS) and the ratio of Cer (d18:1/16:0), Cer (d18:1/18:0) and Cer (d18:1/24:1) to Cer (18:1/24:0), respectively, were calculated as index to evaluate the association between plasma ceramides levels and coronary artery stenosis. Multiple logistic regression analysis was used to establish the prognostic model for the prediction of ACS risk.

RESULTS

After the adjustment by multiple clinical risk factors including age, gender, pre-existing myocardial/cerebral infarction, hemoglobin A1c% (HbA1c%), smoking and the diagnosis during index hospitalization, multiple logistic regression analysis showed that the high ratio of Cer (d18:1/24:1) to Cer (d18:1/24:0), female gender, HbA1c%, unstable angina (UAP) and acute myocardial infarction (AMI) diagnosis (compared with atherosclerosis) during index hospitalization were associated with more severe coronary artery stenosis. Furthermore, the prognostic model was established after adjustment of risk factors and the area under curve (AUC) of receiver operating characteristics (ROC) for the prognostic model was 0.732 and 95% CI was 0.642-0.822.

CONCLUSION

The severity of coronary artery stenosis is associated with high ratio of Cer (d18:1/24:1) to Cer (d18:1/24:0), female gender, HbA1c% and AMI. Although the reported prognostic model showed a good discrimination, further investigation on long term MACE is needed to evaluate the role of ceramide for the prediction of MACE risk.

Drug-coated balloon versus drug-eluting stent for treating de novo coronary lesions in large vessels: a meta-analysis of clinical trials

BACKGROUND

Studies examining the efficiency of drug-coated balloon (DCB) compared to drug-eluting stents (DES) for de novo lesions in large vessels have reported inconsistent results.

OBJECTIVE

This comprehensive meta-analysis of clinical trials compared the efficacy and safety of DCB and DES for the treatment of de novo coronary lesions.

METHODS

The authors formally searched electronic databases before October 2019 to identify randomized and non-randomized clinical trials (RCTs and non-RCTs, respectively). Clinical trials were eligible for inclusion if they compared DCB with DES in patients with coronary lumen diameters >2.5 mm.

RESULTS

Three RCTs and one non-RCT with a total of 321 patients were included in our meta-analysis (DCB group = 152, DES group = 169). The primary endpoint was in-segment late lumen loss (LLL) with a standardized mean difference (SMD) of -0.07 (95% confidence interval [CI]: -0.31, 0.316; P = 0.548) and the secondary endpoint was target lesion revascularization (TLR) with a risk ratio (RR) of 1.17 (95% CI: 0.46, 2.95; P = 0.746).

CONCLUSION

This meta-analysis indicated that DCB might be non-inferior to DES as evidenced by quantitative coronary angiography (QCA) assessed at 6-9 months after percutaneous coronary intervention in patients presenting with coronary artery disease.

Relation between quantity and quality of peri-coronary epicardial adipose tissue and its underlying hemodynamically significant coronary stenosis

BACKGROUND

We aimed to investigate the association of lesion-specific epicardial adipose tissue (EAT) volume and density with the presence of myocardial ischemia.

METHODS

We enrolled 45 patients (55 lesions) with known or suspected coronary artery disease who underwent coronary computed tomography angiography (CTA) followed by invasive fractional flow reserve (FFR) assessment within 30 days. EAT volume (index) and density in patient-, vessel- and lesion-level were measured on CTA images. Lesion-specific ischemia was defined as a lesion with stenosis diameter > 90% or FFR ≤0.80. Multivariate analysis determined the independent association of EAT parameters with lesion-specific ischemia.

RESULTS

Mean age of the patients was 60 years, and 75% were male. Overall, 55.6% of patients had ischemic lesions and a mean FFR baseline value of 0.82 ± 0.10. Total EAT volume index was significantly higher in patients with functionally or anatomically significant stenosis. Specifically, peri-lesion EAT volume index, not the density, was positively correlated with lesion-specific ischemia independent of luminal stenosis and plaque characteristics (hazard ratio 1.56, 95% confidence interval 1.04-2.33, P = 0.032; per 0.1 ml/m² increase). Moreover, peri-lesion EAT volume was negatively correlated with lesion FFR values, whereas total EAT volume was positively correlated with fat accumulation and glucose metabolism. In addition, there was no association of EAT volume or density with myocardial ischemia in vessel-level analysis.

CONCLUSIONS

Lesion-specific EAT volume index, but not density, seems positively and independently associated with myocardial ischemia, while its incremental diagnostic value of lesion-specific ischemia should be further investigated.

Diagnostic Accuracy of Cardiac Magnetic Resonance Versus Fractional Flow Reserve: A Systematic Review and Meta-Analysis

Background

Fractional flow reserve (FFR) is considered the gold standard for diagnosis of coronary artery disease (CAD). Stress Cardiac magnetic resonance (SCMR) has been recently gaining traction as a non-invasive alternative to FFR.

Methods

Studies comparing the diagnostic accuracy of SCMR versus FFR were identified and analyzed using Review Manager (RevMan) 5.3 and Stata software.

Results

A total of 28 studies, comprising 2,387 patients, were included. The pooled sensitivity and specificity for SCMR were 86% and 86% at the patient level, and 82% and 88% at the vessel level, respectively. When the patient-level data were stratified based on the FFR thresholds, higher sensitivity and specificity (both 90%) were noted with the higher cutoff (0.75) and lower cutoff (0.8), respectively. At the vessel level, sensitivity and specificity at the lower FFR threshold were significantly higher at 88% and 89%, compared to the corresponding values for higher cutoff at 0.75. Similarly, meta-regression analysis of SCMR at higher (3T) resolution showed a higher sensitivity of 87% at the patient level and higher specificity of 90% at the vessel level. The highest sensitivity and specificity of SCMR (92% and 94%, respectively) were noted in studies with CAD prevalence greater than 60%.

Conclusions

SCMR has high diagnostic accuracy for CAD comparable to FFR at a spatial resolution of 3T and an FFR cut-off of 0.80. An increase in CAD prevalence further improved the specificity of SCMR.

Inflammasome activation by NLRP1 and NLRC4 in patients with coronary stenosis

OBJECTIVE AND DESIGN

We performed an experimental, analytical and prospective study to evaluate the systemic activation of inflammasome in atherosclerosis' patients, in order to shed light into responsible mechanisms for plaque formation.

SUBJECTS

We included sixty individuals distributed into 3 groups: 2 groups based on the report from the angiography (severe lesions - SL and primary lesions - PL) and 1 group enclosing healthy individuals (HC).

METHODS

The expression assays of inflammasome genes NLRP1, NLRC4, CASP-1 and IL-1β were performed using Real Time qPCR, with specific Taqman Assays. IL-1β serum levels were analysed by commercial kit. Were applied the Shapiro-Wilk and Student's T-test as statistical tests. Statistical significance was set to p ≤ 0.05.

RESULTS

Upregulation of NLRP1 (+3.47 FC, p = 0.0001), NLRC4 (+7.06 FC, p = 6.792 × 10^-09) and IL-1β (+2.43 FC, p = 0.005) was observed in all atherosclerosis patients when compared to HC. According to stenosis severity, patients with primary lesions showed upregulation of inflammasome genes NLRP1 (+2.87 FC, p = 0.0008), NLRC4 (+6.34 FC, p = 4.134 × 10^-07) and IL-1β (+3.39 FC, p = 0.0012) with respect to the HC group. No statistical difference was found in IL-1β serum levels according the assessed groups.

CONCLUSIONS

Inflammasome activation in atherosclerosis's patients can be systemic altered and may be triggered by NLRP1 and NLRC4 receptors. IL-1β gene expression was identified in our study as an important systemic detectable marker of plaque severity.

The impact of iterative reconstruction algorithms on machine learning-based coronary CT angiography-derived fractional flow reserve (CT-FFRML) values

To evaluate the impact of an iterative reconstruction (IR) algorithm (advanced modeled iterative reconstruction, ADMIRE) on machine learning-based coronary computed tomography angiography-derived fractional flow reserve (CT-FFR_ML) measurements compared with filtered back projection (FBP). 170 plaque-containing vessels in 107 patients were included. CT-FFR_ML values were measured and compared among 5 imaging reconstruction algorithms (FBP and ADMIRE at strength levels of 1, 2, 3 and 5). The plaques were classified as, 'calcified" or "noncalcified" and "≥ 50% stenosis" or "< 50% stenosis', a total of four subgroups by consensus. There were no significant differences of CT-FFR_ML values among the FBP and ADMIRE 1, 2, 3 and 5 groups wherever comparisons were done at the level of subgroups (P = 0.676, 0.414, 0.849, 0.873, respectively) or overall (P = 0.072). There were 20, 21, 19, 19 and 29 vessels with lesion-specific ischemia (CT-FFR_ML ≤ 0.80) in FBP and ADMIRE 1, 2, 3 and 5 datasets, respectively, but no statistical differences were found (P = 0.437). Compared with CT-FFR_ML value of FBP dataset, the CT-FFR_ML values of 9 (5.3%) vessels from 8 patients (7.5%) in ADMIRE5 dataset switched from above 0.8 to below or equal to 0.8. There were no significant differences of the CT-FFR_ML values among the FBP and IR image algorithms at different strength levels. However, high iterative strength level (ADMIRE 5) was not recommended, which might have an impact on diagnosis of lesion-specific ischemia, although changes only occurred in a modest number of subjects.

A 90-second magnetocardiogram using a novel analysis system to assess for coronary artery stenosis in Emergency department observation unit chest pain patients

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Magnetocardiography non-invasively detects coronary artery stenosis.

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Emergency department chest pain patients are further evaluated in observation unit.

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Patients underwent 90-second magnetocardiography scan using novel analysis system.

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Results compared to usual care with stress testing and coronary angiography.

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Magnetocardiography shows promise as feasible and comparable testing option.

Background

Magnetocardiography (MCG) has been shown to non-invasively detect coronary artery stenosis (CAS). Emergency department (ED) patients with possible acute coronary syndrome (ACS) are commonly placed in an observation unit (OU) for further evaluation. Our objective was to compare a novel MCG analysis system with stress testing (ST) and/or coronary angiography (CA) in non-high risk EDOU chest pain patients.

Methods

This is a prospective pilot study of non-high risk EDOU chest pain patients evaluated with ST and/or CA that underwent a resting 90-second MCG scan between August 2017 and February 2018. A positive MCG scan was defined as having current dipole deviations with dispersion or splitting during the repolarization phase. ST, CA and major adverse cardiac events (MACE) 30 days and 6 months post-discharge assessed.

Results

Of 101 study patients, mean age was 56 years and 53.6% were male. MCG scan sensitivity with 95% CI was 27.3% [7.3%, 60.7%], specificity 77.8% [67.5%, 85.6%], PPV 13.0% [3.4%, 34.7%] and NPV 89.7% [80.3%, 95.2%] compared to ST, and 33.3% [7.5%, 70.7%], 78.3% [68.4%, 86.2%], 13% [5.2%, 29.0%] and 92.3% [88.2%, 95.1%] respectively compared to ST and CA. No patients had positive ST, CA or MACE 30 days and 6 months post-discharge.

Conclusion

This pilot study suggests a resting 90-second MCG scan shows promise in evaluating EDOU chest pain patients for CAS and warrants further study as an alternative testing modality to identify patients safe for discharge. Larger studies are needed to assess accuracy of MCG using this novel analysis system.

Clinical Impact of High-Sensitivity Cardiac Troponin T on the Chronic Phase of Stable Angina after a Successful Initial Percutaneous Coronary Intervention

BACKGROUND

The purpose of this study was to investigate the clinical significance of elevated plasma high-sensitivity troponin T (hs-TnT) in the chronic phase in patients with stable angina pectoris (SAP) who underwent a successful percutaneous coronary intervention (PCI).

METHODS

This study enrolled 158 consecutive SAP patients who underwent routine follow-up coronary angiography 9 months after a successful PCI with the implantation of a second-generation drug-eluting stent. Patients with previous coronary artery bypass graft and renal dysfunction were excluded. Patients were divided into two groups according to hs-TnT plasma level at follow-up: elevated hs-TnT (≥ 0.015 ng/ml) group and non-elevated hs-TnT group.

RESULTS

Among the 158 subjects, 42 had an elevated hs-TnT level at follow-up. The elevated hs-TnT group had a significantly higher rate of any coronary lesion (in-stent restenosis and de novo lesions) in follow-up CAG (coronary angiography) than the non-elevated group (28.6% vs. 10.3%, p < 0.05). Multivariate analysis also showed that hs-TnT elevation was independently associated with the presence of significant coronary stenosis in the chronic phase (odds ratio: 3.99, 95% confidence interval: 1.38 to 11.53). The best cut-off value of the hs-TnT level at 9 months after a successful PCI to predict the presence of significant coronary stenosis was 0.016 ng/ml (sensitivity: 50.0%; specificity: 82.1%; area under the receiver operating characteristic curve: 0.67).

CONCLUSIONS

hs-TnT elevation was independently associated with the presence of coronary stenosis in the chronic phase in SAP patients with successful PCI. Routine measurement of hs-TnT in the chronic phase may be useful to refine the risk of patients after PCI.

Potential Gains of Screening Family Members of Suspected Coronary Artery Disease: A Pilot Study

Background:

Early diagnosis of asymptomatic coronary artery disease (CAD) is presently targeted in preventive cardiology. A positive family history though not modifiable can provide a window of opportunity for intervening on modifiable risk factors. We assessed the prevalence of risk factors among the family members of suspected CAD patients and estimated their 10 years CAD risk.

Methods:

In a hospital-based cross-sectional study, socio-demographic, personal data and blood samples for total and HDL cholesterol were collected. The risk of having a heart attack in the next 10 years was calculated using Framingham Risk Score.

Results:

The mean age of participants (n = 60) was 40.55 ± 1.78 years. 85% were physically inactive. Smoking (13%), alcohol use (12%), history of CAD (2%), HTN (12%) and diabetes (22%) were the observed risk factors. A family history of CAD at <40 years of age was reported by 7% of subjects. Prevalence of overweight was 21% and 11% were obese. Increased waist-hip ratio (43%), diabetes (22%), hypercholesterolemia (28%), reduced HDL Cholesterol (48%) were other prevalent risk factors. Risk of CAD of >1% in the next 10 years was noted among 60% of subjects.

Conclusions:

Window of opportunity for secondary prevention exists among the family members of suspected CAD.

[Radiological imaging to assess individual cardiovascular risk]

CLINICAL/METHODICAL ISSUE

Radiologic imaging for the assessment of individual cardiovascular risk.

STANDARD RADIOLOGICAL METHODS

The correct estimation of the individual cardiovascular risk is prerequisite for the prevention of cardiovascular diseases. Here, extensive evidence is available for coronary calcium scans as well as coronary CT angiography (CTA).

METHODICAL INNOVATIONS

Summary of the available evidence for the use of calcium score and coronary CTA. Illustration of the significance of both tests in current guidelines.

PERFORMANCE

Both tests have high prognostic value, surpassing a risk-factor based assessment. In comparison with the calcium score, the CTA has higher incremental value.

ACHIEVEMENTS

Results from recent trials confirm an improvement of outcomes in symptomatic patients by performing a CTA compared with standard care.

PRACTICAL RECOMMENDATIONS

European and US guidelines recommend a calcium score for risk stratification of asymptomatic patients with a low to intermediate risk profile. For symptomatic patients with low to intermediate coronary artery disease pretest probability, a CTA is recommended.

Latent tuberculosis infection among patients with coronary artery stenosis: A case-Control study

Background

The activation of the cell-mediated immune responses by Mycobacterium tuberculosis can promote atherogenesis.

Aims

The aim of this study is to determine the frequency of latent tuberculosis infection (LTBI) among patients with coronary artery stenosis (CAS) and to explore the association between LTBI and development of CAS. We conducted a case-control study which included 183 patients' who underwent percutaneous coronary angiography (121 patients with CAS and 62 patients without as a control group).

Methods

For all the study population, clinical evaluation, tuberculin skin test (TST), imaging studies (including chest radiography and echocardiography), laboratory investigations, and electrocardiography were carried out. Only for the patients with positive TST, QuantiFERON-TB Gold test was performed. Predictors of CAS were identified using univariate analyses (Yates' corrected Chi-square test or Fischer's exact test) followed by multivariate analysis (binary logistic regression).

Results

Among 29.5% of the study population, LTBI was detected, and among patients with CAS, 56.2% of patients had advanced CAS. After multivariate analysis, it was found that metabolic syndrome (MS) (odds ratio [OR] 3.6, 95% confidence interval [CI] 1.5-22.6, P = 0.022) and LTBI (OR 2.5, 95% CI 1.2-17.3, P = 0.018) were the predictors of CAS among the study population, while only diabetes mellitus (DM) (OR 1.9, 95% CI 1.1-11.7, P = 0.031) was the predictor of advanced CAS.

Conclusion

LTBI is associated with the development of CAS. In addition, MS is associated with CAS, while its related disorder, DM, is associated with advanced CAS.

The relationship between radiation doses to coronary arteries and location of coronary stenosis requiring intervention in breast cancer survivors

Background

To assess the relationship between radiation doses to the coronary arteries (CAs) and location of a coronary stenosis that required intervention after three-dimensional conformal radiotherapy (3DCRT) for breast cancer (BC).

Methods

The study population consisted of 182 women treated for BC in Sweden between 1992 and 2012. All women received 3DCRT and subsequently underwent coronary angiography due to a suspected coronary event. CA segments were delineated in the patient’s original planning-CT and radiation doses were recalculated based on the dose distribution of the original radiotherapy (RT) plan. The location of the CA stenosis that required intervention was identified from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR). Logistic regression analysis was used to assess the relationship between CA radiation doses and risk of a later coronary intervention at this specific location.

Results

The odds ratio (OR) varied by radiation dose to the mid left anterior descending artery (LAD) (p = 0.005). Women receiving mean doses of 1–5 Gray (Gy) to the mid LAD had an adjusted OR of 0.90 (95% CI 0.47–1.74) for a later coronary intervention compared to women receiving mean doses of 0–1 Gy to the mid LAD. In women receiving mean doses of 5–20 Gy to the mid LAD, an adjusted OR of 1.24 (95% CI 0.52–2.95) was observed, which increased to an OR of 5.23 (95% CI 2.01–13.6) for mean doses over 20 Gy, when compared to women receiving mean doses of 0–1 Gy to the mid LAD.

Conclusions

In women receiving conventional 3DCRT for BC between 1992 and 2012, radiation doses to the LAD remained high and were associated with an increased requirement of coronary intervention in mid LAD. The results support that the LAD radiation dose should be considered in RT treatment planning and that the dose should be kept as low as possible. Minimising the dose to LAD is expected to diminish the risk of later radiation-induced stenosis.

Electronic supplementary material

The online version of this article (10.1186/s13014-019-1242-z) contains supplementary material, which is available to authorized users.

Assessment of coronary flow velocity reserve with phase-contrast cine magnetic resonance imaging in patients with heavy coronary calcification

Coronary flow velocity reserve (CFVR) can be noninvasively measured by phase-contrast cine magnetic resonance imaging (PC-MRI). Heavy coronary calcification degrades the diagnostic accuracy for the detection of coronary arterial stenosis on computed tomography (CT). The aim of this study was to evaluate the value of CFVR measurement with PC-MRI for detecting significant coronary stenoses in patients with heavy coronary calcification. Sixteen patients (71 ± 8 years) with coronary calcium score above 400 who had suspected moderate coronary stenosis (50-69% diameter stenosis) on CT angiography were prospectively studied. The CFVR values, calculated as the ratio of peak flow velocity during hyperemia to the peak flow velocity at rest, were measured using breath-hold PC-MRI with 3 T system, and were compared with the results of quantitative coronary angiography (QCA). The mean coronary calcium score was 985 ± 378. CFVR was successfully determined with PC-MRI in 17/18 (94%) vessels. Using a threshold of 1.4 for CFVR, the sensitivity, specificity, and positive and negative predictive value for detecting ≥ 50% stenosis on QCA was 88% (7/8), 89% (8/9), 88% (7/8), 89% (8/9), respectively. When MRI CFVR measurements was added to CT angiography for the evaluation of coronary stenosis, the positive predictive value was 88% (7/8), while the positive predictive value of CT angiography alone was 44% (8/18). PC-MRI can provide noninvasive detection of altered CFVR caused by significant stenosis in patient. CFVR measurement by PC-MRI is useful for diagnosing physiologically significant coronary stenosis in patients with high calcium score on CT.

Instantaneous wave-free ratio (iFR®) to determine hemodynamically significant coronary stenosis: A comprehensive review

Coronary angiography is considered to be the gold standard in the morphological evaluation of coronary artery stenosis. The morphological assessment of the severity of a coronary lesion is very subjective. Thus, the invasive fractional flow reserve (FFR) measurement represents the current standard for estimation of the hemodynamic significance of coronary artery stenosis. The FFR-guided revascularization strategy was initially classified as a Class-IA-recommendation in the 2014 European Society of Cardiology/European Association for Cardio-Thoracic Surgery guidelines on myocardial revascularization. Both the Deferral vs Performance of Percutaneous Coronary Intervention of Functionally Non-Significant Coronary Stenosis and Flow Reserve vs Angiography for Multivessel Evaluation studies showed no treatment advantage for hemodynamically insignificant stenoses. With the help of FFR (and targeted interventions), clinical results could be improved; however, the use in clinical practice is still limited due to the need of adenosine administration and a significant prolongation of the length of the procedure. Instantaneous wave-free ratio (iFR®) is a new innovative approach for the determination of the hemodynamic significance of coronary stenosis, which can be obtained at rest without the use of vasodilators. Regarding the periprocedural complications as well as prognosis, iFR® showed non-inferiority to FFR in the SWEDEHEART and DEFINE-FLAIR trials. Furthermore, iFR®, enhanced by iFR®-pullback, provides the possibility to display the iFR®-change over the course of the vessel to create a hemodynamic map.

Correlation of FFR-derived from CT and stress perfusion CMR with invasive FFR in intermediate-grade coronary artery stenosis

Only one-third of intermediate-grade coronary artery stenosis (i.e. 40-70% diameter narrowing) causes myocardial ischemia, requiring most often additional invasive work-up with invasive fractional flow reserve (FFR). To evaluate the correlations between FFR estimates derived from computed tomography (FFR_CT) and adenosine perfusion cardiac magnetic resonance (CMR) with invasive FFR in intermediate-grade stenosis. Thirty-seven patients (mean age 61 ± 9 years; 25 men) who underwent adenosine perfusion CMR, quantitative coronary angiography and FFR in the work-up for intermediate-grade stenoses (n = 39) diagnosed at coronary CT angiography were retrospectively evaluated. Blinded FFR_CT analysis was computed on each intermediate-grade lesion and correlated to the FFR values. On adenosine CMR, subendocardial time-enhancement maximal upslopes, normalized by respective left ventricle cavity upslopes, were obtained distal to a coronary stenosis (RISK area) and in remote myocardium (REMOTE area). The perfusion was subsequently assessed without (uncorrected RISK) and after correction for remote perfusion (relative myocardial perfusion index = REMOTE/RISK ratio), and then correlated to the FFR values. Differences in correlations were tested with z statistics and considered statistically significant different at a p < 0.05 level. The average FFR value was 0.85 ± 0.10 (0.60-0.98 range), 28% (n = 11) was ≤ 0.80. FFR value correlated poorly with uncorrected RISK upslopes (r = 0.151; p = 0.36), but equally strongly with FFR_CT (r = 0.675; p < 0.001) and the relative myocardial perfusion index (r = - 0.63) (p < 0.001; z = 6.72) for assessment of lesion-specific ischemia. Both FFR_CT and adenosine perfusion CMR strongly correlate with invasive FFR measurements for intermediate-grade stenosis. These preliminary findings pave the way for further studies evaluating non-invasively intermediate coronary stenosis in clinical practice.

Concertina Phenomenon in the Left Anterior Descending Artery: An Unexpected Circumstance in an Unexpected Vessel

The concertina phenomenon is the occurrence of new and transient angiographic series of pseudolesions in a tortuous vessel induced mainly by a stiff guide wire. Here, we describe a 53-year-old man who experienced a concertina effect in the left anterior descending coronary artery (LAD) during an elective percutaneous coronary intervention. After the diagnosis of the concertina phenomenon in the LAD, a percutaneous coronary intervention was performed following the withdrawal of the soft guide wire to the mid level of the LAD. After the intervention, the patient remained in very good clinical status and was discharged on the third postprocedural day.

Discordance between pressure drift after wire pullback and intracoronary distal pressure offset affects stenosis physiology appraisal

BACKGROUND

Drift is a well-known issue affecting intracoronary pressure measurements. A small pressure offset at the end of the procedure is generally considered acceptable, while repeat assessment is advised for drift exceeding ±2 mmHg. This practice implies that drift assessed after wire pullback equals that at the time of stenosis appraisal, but this assumption has not been systematically investigated. Our aim was to compare intra-and post-procedural pressure sensor drift and assess benefits of correction for intra-procedural drift and its effect on diagnostic classification.

METHODS

In 70 patients we compared intra- and post-procedural pressure drift for 120 hemodynamic tracings obtained at baseline and throughout the hyperemic response to intracoronary adenosine. Intra-procedural drift was derived from the intercept of the stenosis pressure gradient-velocity relationship. Diagnostic reclassification after correction for intra-procedural drift was assessed for the mean distal-to-aortic pressure ratio at baseline (Pd/Pa) and hyperemia (fractional flow reserve, FFR), and corresponding stenosis resistances.

RESULTS

Post- and intra-procedural drift exceeding the tolerated threshold was observed in 73% and 64% of the hemodynamic tracings, respectively. Discordance in terms of acceptable drift level was present for 42% of the tracings, with avoidable repeat physiological assessment in 25% and unacceptable intra-procedural drift unrecognized at final drift check in 17% of the tracings. Correction for intra-procedural drift caused higher reclassification rates for baseline than hyperemic functional indices.

CONCLUSIONS

Post-procedural pressure drift frequently does not match drift during physiological assessment. Tracing-specific correction for intra-procedural drift can potentially lower the risk of inadvertent diagnostic misclassification and prevent unnecessary repeats.

The characteristics of coronary stenosis in 11,267 patients from Southwest China: a retrospective study

The characteristics of coronary stenosis vary among the different countries or areas. 11,267 patients who have undergone coronary angiography (CAG) from three Southwest China hospitals were investigated. Patient characteristics, coronary stenosis and stent-implant information were recorded and analyzed according to two criteria: "visible stenosis" and "≥ 50% stenosis". The patients who have undergone CAG increased year by year, with patients from 60 to 69 years-old taking the highest ratio (34.69%). Based on the "≥ 50% stenosis" criteria, the stenotic frequency was 40.54% for Southwest China patients getting CAG. Only 8.14% patients suffered ≥ 3 stenotic vessels, while 11.58 and 20.82% patients had 2 or 1 stenotic vessel, respectively. However, when using the "visible stenosis" criteria, the stenotic frequency increased to 64.68%. The prevalence of stenosis increased with age based on the "visible stenosis" criteria. There were more male patients with stenosis than female except patients over 80 years old. The stenosis affected almost all main coronary arteries and their branches, with the most affected artery being the left anterior descending artery. There were 3246 cases (28.8%) implanted with 5423 stents with a concurrent age-dependent increasing tendency for stent-implant frequency and average implanted stent number. The numbers of patients who have undergone CAG and suffered from CVD increased rapidly. In these patients, positive rate of CAG was 64.67%, which increased to 72.2% in patients over 60-years old. The incidence of ≥ 75% stenosis and multiple stenosis increased with age, however it should be noticed there were 18.93% for ≥ 75% stenosis and 19.52% for multiple stenosis in patients under 40 years old.

Peripheral-blood gene expression profiling studies for coronary artery disease and its severity in Xinjiang population in China

Background

Alterations in gene expression in peripheral blood cells play a curtail role in the presence and extent of coronary artery disease (CAD), but its severity reflected by gene expression alterations in peripheral blood cells is still unknown in Xinjiang population in China.

Methods

Global gene expression profiling in peripheral blood was used to explore differentially expressed genes in coronary artery stenosis patients. RNA was extracted from peripheral blood of 9 controls without coronary stenosis and 21 cases with angiographically CAD. The extent of CAD severity was categorized angiographically as no CAD, mild CAD (20 to 50% luminal diameter stenosis [LDS]), moderate CAD (50 to 75% LDS) and severe CAD (≥75% LDS). Differentially expressed genes related with CAD severity from peripheral blood cells were screened by linear mixed effects analysis using the lme4 package in R. Then the differentially expressed genes that gradually up-regulated or down-regulated were enriched by Gene Ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis.

Results

The most significantly enrichments were toll-like receptor signaling pathway, immune responses, translational processes, cellular growth, inflammation and metabolic processes. Combined with NCBI-GeneRIF and PubMed analysis, we focused on the 12 genes associated with toll-like receptor signaling pathway in the extent of coronary artery stenosis patients. Receiver operating characteristic (ROC) analysis of 12 genes associated with toll-receptor signaling pathway in the 236 CAD patients from GEO database demonstrated that 12 genes expression could predict severe CAD with an area under the curve of 0.67, sensitivity of 77.65% and specificity of 51.52%.

Conclusion

These results suggest that 12 genes associated with toll-like receptor signaling pathway in peripheral-blood cells reflect the presence and extent of CAD severity in Xinjiang population in China.

Electronic supplementary material

The online version of this article (10.1186/s12944-018-0798-1) contains supplementary material, which is available to authorized users.

The clinical evaluation of the CADence device in the acoustic detection of coronary artery disease

The noninvasive detection of turbulent coronary flow may enable diagnosis of significant coronary artery disease (CAD) using novel sensor and analytic technology. Eligible patients (n = 1013) with chest pain and CAD risk factors undergoing nuclear stress testing were studied using the CADence (AUM Cardiovascular Inc., Northfield MN) acoustic detection (AD) system. The trial was designed to demonstrate non-inferiority of AD for diagnostic accuracy in detecting significant CAD as compared to an objective performance criteria (sensitivity 83% and specificity 80%, with 15% non-inferiority margins) for nuclear stress testing. AD analysis was blinded to clinical, core lab-adjudicated angiographic, and nuclear data. The presence of significant CAD was determined by computed tomographic (CCTA) or invasive angiography. A total of 1013 subjects without prior coronary revascularization or Q-wave myocardial infarction were enrolled. Primary analysis was performed on subjects with complete angiographic and AD data (n = 763) including 111 subjects (15%) with severe CAD based on CCTA (n = 34) and invasive angiography (n = 77). The sensitivity and specificity of AD were 78% (p = 0.012 for non-inferiority) and 35% (p < 0.001 for failure to demonstrate non-inferiority), respectively. AD results had a high 91% negative predictive value for the presence of significant CAD. AD testing failed to demonstrate non-inferior diagnostic accuracy as compared to the historical performance of a nuclear stress OPC due to low specificity. AD sensitivity was non-inferior in detecting significant CAD with a high negative predictive value supporting a potential value in excluding CAD.

Instantaneous wave-free ratio and fractional flow reserve in clinical practice

Objectives

To compare fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) measurements in an all-comer patient population with moderate coronary artery stenoses.

Background

Visual assessment of the severity of coronary artery stenoses is often discordant in moderate lesions. FFR allows reliable functional severity assessment in these cases but requires adenosine-induced hyperaemia with associated additional time, costs and side effects. The iFR is a hyperaemia-independent index.

Methods and results

Between November 2015 and February 2017, 356 consecutive patients were included in whom 515 coronary stenoses were measured using both iFR and FFR. Mean iFR and FFR were 0.90 ± 0.09 and 0.86 ± 0.08, respectively. iFR correlated well with FFR [r = 0.75; p < 0.001]. Receiver operating characteristic analysis identified an area under the curve of 0.92. An iFR-only strategy with a treatment cut-off ≤0.89 revealed a diagnostic classification agreement with the FFR-only strategy in 420 lesions (82%) with a sensitivity of 87%, a specificity of 80%, a positive predictive value of 56% and a negative predictive value of 96%.

Conclusions

Real-time iFR measurements have good negative predictive value compared to FFR, but moderate diagnostic accuracy (82%). It exposes fewer patients to adenosine, reduces procedure time and costs. Further prospective trials are needed to evaluate specific clinical settings, cut-off values and endpoints.

High Brachial Ankle Pulse Wave Velocity as a Marker for Predicting Coronary Artery Stenosis in Patients with Type 2 Diabetes

BACKGROUND

We evaluated the ability of brachial ankle pulse wave velocity (baPWV) to predict coronary artery stenosis (CAS) in patients with type 2 diabetes, and compared the predictive power of baPWV to that of well-known cardiovascular disease (CVD) risk calculators.

METHODS

The study group included 83 consecutive patients over 30 years old with type 2 diabetes who complained of vague chest discomfort. An automatic pulse waveform analyzer was used to measure baPWV. CAS was measured using multi-slice computed tomographic (MSCT) angiography.

RESULTS

Age, maximal baPWV, duration of diabetes, current smoking, the UK Prospective Diabetes Study (UKPDS) Risk Engine score, American College of Cardiology/American Heart Association (ACC/AHA) risk estimator score, the Framingham risk calculator score, and coronary artery calcium score were greater in patients with CAS than in those without CAS. An area under the curve (AUC) indicative of a predictive value for CAS (≥20%) was found for several parameters. The AUC of maximal baPWV, the UKPDS Risk Engine, the ACC/AHA ASCVD risk estimator, and the Framingham risk calculator were 0.672 (95% confidence interval [CI], 0.554 to 0.785; P=0.010), 0.777 (95% CI, 0.675 to 0.878; P<0.001), 0.763 (95% CI, 0.660 to 0.866; P<0.001), and 0.736 (95% CI, 0.629 to 0.843; P<0.001), respectively. The optimal cutoff value of baPWV for the detection of CAS was 1,650 cm/sec (sensitivity, 68.9%; specificity, 63.2%).

CONCLUSION

Maximal baPWV was closely related with CAS detected by MSCT coronary angiography in patients with type 2 diabetes. baPWV has the potential to be a useful, noninvasive screening tool for the prediction of occult CAS in patients with type 2 diabetes.

Integrated prediction of lesion-specific ischaemia from quantitative coronary CT angiography using machine learning: a multicentre study. Eur Radiol. 2018;28:2655-2664. [PMID: 29352380 DOI: 10.1007/s00330-017-5223-z]

OBJECTIVES

We aimed to investigate if lesion-specific ischaemia by invasive fractional flow reserve (FFR) can be predicted by an integrated machine learning (ML) ischaemia risk score from quantitative plaque measures from coronary computed tomography angiography (CTA).

METHODS

In a multicentre trial of 254 patients, CTA and invasive coronary angiography were performed, with FFR in 484 vessels. CTA data sets were analysed by semi-automated software to quantify stenosis and non-calcified (NCP), low-density NCP (LD-NCP, < 30 HU), calcified and total plaque volumes, contrast density difference (CDD, maximum difference in luminal attenuation per unit area) and plaque length. ML integration included automated feature selection and model building from quantitative CTA with a boosted ensemble algorithm, and tenfold stratified cross-validation.

RESULTS

Eighty patients had ischaemia by FFR (FFR ≤ 0.80) in 100 vessels. Information gain for predicting ischaemia was highest for CDD (0.172), followed by LD-NCP (0.125), NCP (0.097), and total plaque volumes (0.092). ML exhibited higher area-under-the-curve (0.84) than individual CTA measures, including stenosis (0.76), LD-NCP volume (0.77), total plaque volume (0.74) and pre-test likelihood of coronary artery disease (CAD) (0.63); p < 0.006.

CONCLUSIONS

Integrated ML ischaemia risk score improved the prediction of lesion-specific ischaemia by invasive FFR, over stenosis, plaque measures and pre-test likelihood of CAD.

KEY POINTS

• Integrated ischaemia risk score improved prediction of ischaemia over quantitative plaque measures • Integrated ischaemia risk score showed higher prediction of ischaemia than standard approach • Contrast density difference had the highest information gain to identify lesion-specific ischaemia.

Clinical implications of guiding catheter extubation during fractional flow reserve measurements

BACKGROUND

Fractional flow reserve (FFR) is defined by the maximal coronary flow ratio with and without stenosis.

AIMS

We hypothesized that guiding catheter intubation in coronary ostia during FFR measurements may underestimate FFR value by limiting the increase of coronary flow during maximal hyperaemia.

METHODS

Between June 2013 and January 2014, we prospectively included all patients with i.v. adenosine FFR measurements. FFR was measured with the guiding catheter intubated in the coronary ostia (FFR_int) and extubated in the aorta (FFR_ext). We calculated the ratio between coronary ostium assessed by quantitative coronary angiography and guiding catheter surfaces, defined as the free ostial lumen ratio.

RESULTS

In total, 151 lesions in 104 patients were included; 121 lesions and 88 patients were eligible for analysis. Mean±SD FFR_ext was significantly lower compared with FFR_int; 0.82±0.08 and 0.84±0.08, respectively (P<0.001). Revascularization indication changed in 14 patients (16%). The difference induced by guiding extubation correlated significantly with the free ostial lumen ratio (R²=0.06, P=0.008).

CONCLUSION

FFR value is significantly lower when the guiding catheter is extubated. The smaller the coronary ostium, the greater the difference observed between FFR_ext and FFR_int. Guiding extubation during FFR measurements changed the revascularization indication in 16% of cases.

CAD-RADS - a new clinical decision support tool for coronary computed tomography angiography

Coronary computed tomography angiography (CTA) has been established as an accurate method to non-invasively assess coronary artery disease (CAD). The proposed 'Coronary Artery Disease Reporting and Data System' (CAD-RADS) may enable standardised reporting of the broad spectrum of coronary CTA findings related to the presence, extent and composition of coronary atherosclerosis. The CAD-RADS classification is a comprehensive tool for summarising findings on a per-patient-basis dependent on the highest-grade coronary artery lesion, ranging from CAD-RADS 0 (absence of CAD) to CAD-RADS 5 (total occlusion of a coronary artery). In addition, it provides suggestions for clinical management for each classification, including further testing and therapeutic options. Despite some limitations, CAD-RADS may facilitate improved communication between imagers and patient caregivers. As such, CAD-RADS may enable a more efficient use of coronary CTA leading to more accurate utilisation of invasive coronary angiograms. Furthermore, widespread use of CAD-RADS may facilitate registry-based research of diagnostic and prognostic aspects of CTA.

KEY POINTS

• CAD-RADS is a tool for standardising coronary CTA reports. • CAD-RADS includes clinical treatment recommendations based on CTA findings. • CAD-RADS has the potential to reduce variability of CTA reports.

Improved diagnostic performance of transluminal attenuation gradient in combination with morphological evaluation of coronary artery stenosis using 320-row computed tomography

PURPOSE

To assess the utility of transluminal attenuation gradient (TAG) in combination with coronary computed tomography angiography (CTA) for detecting obstructive coronary artery stenosis.

MATERIALS AND METHODS

We retrospectively evaluated coronary CTA data in 35 consecutive patients who underwent invasive coronary angiography (ICA). We compared the diagnostic performance of TAG with that of quantitative coronary angiography, which we used as the reference standard. For the combination of TAG and coronary CTA, we designed a logical conjunction model (CCTA&&TAG) as well as a logical disjunction model (CCTA||TAG), and evaluated their diagnostic accuracies.

RESULTS

Among 130 vessels of 35 patients, 30 lesions (23%) showed significant stenosis on ICA. TAG predicted significant coronary artery stenosis with a sensitivity of 75%, specificity of 63%, positive predictive value of 40%, negative predictive value of 89%, and accuracy of 66%, and had a cutoff value of - 15.4 HU/10 mm. The respective values for CCTA&&TAG were 73, 98, 88, 90, and 90%; those for CCTA||TAG were 94, 61, 56, 94, and 72%. CCTA&&TAG improved the diagnostic accuracy significantly more than CCTA||TAG.

CONCLUSION

TAG in conjunction with coronary CTA improves the diagnostic accuracy of coronary CTA.

Extent of Coronary Stenosis and Anxiety Symptoms among Patients Undergoing Coronary Angiography

Background: The association between coronary angiographic findings and the level of anxiety symptoms among patients who undergo coronary angiography is not known. The aim of this study was to investigate the association between the extent of coronary stenosis and anxiety symptoms in patients who undergo coronary angiography. Methods: In a cross-sectional study, 106 patients who underwent coronary angiography and had varying degrees of coronary artery disease were enrolled. Demographic characteristics (i.e., age and gender), socioeconomic status (i.e., educational attainment, income, and marital status), and traditional risk factors (i.e., hypertension, diabetes mellitus, hyperlipidemia, and smoking) were measured. The independent variable was the extent of coronary stenosis shown by coronary angiography, coded as single-vessel disease (n = 19), 2-vessel disease (n = 28), or 3-vessel disease (n = 59). The main outcome was symptoms of anxiety measured using the Hospital Anxiety Depression Scale (HADS). The Kruskal-Wallis test was used for bivariate analysis, and linear regression was applied for multivariable analysis. Results: Participants were mostly men (n = 78, 73%), at a mean age of 50.14 ± 10.60 years. We found an inverse association between the extent of coronary stenosis and anxiety symptoms in our samples. Anxiety symptoms were lowest in the patients with 3-vessel disease and highest in those with single-vessel disease. The above association remained significant in a linear regression model, controlled for the demographic, socioeconomic, and traditional risk factors. Conclusion: An inverse association may exist between the extent of coronary stenosis and the severity of anxiety symptoms in patients who undergo coronary angiography. Patients who undergo angiography and have fewer angiographic findings require screening for anxiety symptoms.

Association of serum uric acid level with coronary artery stenosis severity in Korean end-stage renal disease patients

Background

Hyperuricemia is common in end-stage renal disease (ESRD) patients, and many previous studies have reported the associations between hyperuricemia and adverse cardiovascular outcomes, which are the major cause of death in such patients. We investigated the relationship between serum uric acid level and the severity of coronary stenosis in ESRD patients on maintenance hemodialysis (MHD).

Methods

Among 721 patients who started MHD treatment, 102 underwent coronary angiographic tests complaining of chest discomfort that was new at initiation of MHD. We collected data on uric acid level and coronary artery luminal diameter, defining luminal diameter narrowing of more than 50% in any major coronary artery as critical-stenosis.

Results

We detected critical coronary artery stenosis in 52 (57.8%) patients. The mean uric acid level was 6.6 ± 2.2 mg/dL, and that was significantly higher in the critical-stenosis group (4.9 ± 1.4 mg/dL vs. 7.8 ± 2.0 mg/dL, P < 0.001). The only independent predictor of critical-stenosis in multivariate analysis was serum uric acid level (P < 0.001).

Conclusion

High serum uric acid was associated with severe coronary artery stenosis in Korean ESRD patients. Hyperuricemia is a readily modifiable factor, and appropriately preventing it could provide significant benefits in ESRD patients.

Age- and sex-based resource utilisation and costs in patients with acute chest pain undergoing cardiac CT angiography: pooled evidence from ROMICAT II and ACRIN-PA trials

OBJECTIVES

To determine resource utilisation according to age and gender-specific subgroups in two large randomized diagnostic trials.

METHODS

We pooled patient-specific data from ACRIN-PA 4005 and ROMICAT II that enrolled subjects with acute chest pain at 14 US sites. Subjects were randomized between a standard work-up and a pathway utilizing cardiac computed tomography angiography (CCTA) and followed for the occurrence of acute coronary syndrome (ACS) and resource utilisation during index hospitalisation and 1-month follow-up. Study endpoints included diagnostic accuracy of CCTA for the detection of ACS as well as resource utilisation.

RESULTS

Among 1240 patients who underwent CCTA, negative predictive value of CCTA to rule out ACS remained very high (≥99.4%). The proportion of patients undergoing additional diagnostic testing and cost increased with age for both sexes (p < 0.001), and was higher in men as compared to women older than 60 years (43.1% vs. 23.4% and $4559 ± 3382 vs. $3179 ± 2562, p < 0.01; respectively). Cost to rule out ACS was higher in men (p < 0.001) and significantly higher for patients older than 60 years ($2860-5935 in men, p < 0.001).

CONCLUSIONS

CCTA strategy in patients with acute chest pain results in varying resource utilisation according to age and gender-specific subgroups, mandating improved selection for advanced imaging.

KEY POINTS

• In this analysis, CAD and ACS increased with age and male gender. • CCTA in patients with acute chest pain results in varying resource utilisation. • Significant increase of diagnostic testing and cost with age for both sexes. • Cost to rule out ACS is higher in men and patients >60 years. • Improved selection of subjects for cardiac CTA result in more resource-driven implementation.

[Instantaneous wave-free ratio (iFR®) in patients with coronary artery disease]

Coronary angiography is considered as the gold standard in the morphological representation of coronary artery stenosis. Coronary angiography is often performed without preprocedural non-invasive proof of ischemia and the assessment of the severity of a coronary lesion by morphology is very subjective. Thus, invasive fractional flow reserve (FFR) measurement represents the current standard for estimation of the hemodynamic relevance of coronary artery stenosis and facilitates decision making for percutaneous coronary intervention (PCI) and stenting. The FFR-guided revascularization strategy has been classified as a class IA recommendation in the 2014 ESC/EACTS guidelines on myocardial revascularization. Both the DEFER and the FAME studies showed no treatment advantage of hemodynamically irrelevant stenosis. By use of FFR (and targeted interventions), clinical results could be improved as well as the procedure costs were reduced; however, the use in clinical practice is still limited due to the need of adenosine administration and a significant prolongation of the procedure. Instantaneous wave-free ratio (iFR®) is a new innovative approach for the determination of the hemodynamic relevance of coronary stenosis which can be obtained at rest without the use of vasodilators. Regarding periprocedural complications as well as prognosis, iFR® showed non-inferiority compared to FFR in the SWEDEHEART and DEFINE-FLAIR trials.

The association of epicardial fat volume with coronary characteristics and clinical outcome

Recent studies have demonstrated the relationship between epicardial fat volume (EFV) and coronary atherosclerosis, but their association is modest at best. Our purpose is to elucidate the association of epicardial fat with coronary characteristics and clinical outcome. We performed coronary computed tomographic angiography in 651 patients and divided them into three groups according to tertiles of EFV; low-tertile (n = 215), 36-123 ml; middle-tertile (n = 218), 124-165 ml; high-tertile (n = 218), 166-489 ml. The prevalence of coronary calcium score (CCS) >0 (71.6, 73.4, and 83.9% in low-, middle-, and high-tertile group, respectively) and CCS >100 (39.1, 39.9, and 59.2% in each group) was significantly higher in patients with high-tertile EFV compared to the other two groups (p = 0.0047 and p < 0.0001, respectively). The prevalence of CCS >400 was 17.2, 25.7, and 33.1% in each group, which increased stepwise as EFV increased. The significant stenosis (36.2 vs. 27.0%, p = 0.0383), total coronary occlusion (5.5 vs. 0.9%, p = 0.0156), and high-risk plaque (11.0 vs. 5.6%, p = 0.0368) were more prevalent in patients with high-tertile EFV compared to those with low-tertile EFV. The combined rate of cardiac death and myocardial infarction was 0.9, 2.3, and 6.4% in each patient group, respectively, which was significantly higher in patients with high-tertile EFV compared to those with low-tertile EFV (p = 0.0004). The prevalence of coronary artery calcium, significant stenosis, and high-risk plaque increased sharply in patients with high EFV, which was associated with higher rate of cardiac death and myocardial infarction. Thus, high EFV was associated with advanced coronary atherosclerosis and poor prognosis.

Impact of Stent Type and Presence of Vasospastic Angina on Long-Term Prognosis

BACKGROUND

Little is known about the impact of stent type on the prognosis of vasospastic angina (VSA) in patients who undergo stent implantation.Methods and Results:We evaluated consecutive patients undergoing coronary angiography with positive (n=650; VSA) and negative (n=2,872; non-VSA) ergonovine testing. Among them, 304 patients undergoing stent implantation for organic stenosis were classified for comparison into 3 respective VSA and non-VSA groups based on stent type (68 and 78 with bare-metal stent [BMS]; 21 and 49 with sirolimus-eluting stent [SES]; 26 and 62 with newer generation drug-eluting stent [N-DES]). The primary outcome was defined as target lesion revascularization, target vessel revascularization, emergency coronary angiography, and cardiac death. The 2-year cumulative incidence of the primary outcome was significantly higher in the VSA group than non-VSA group after SES implantation (38.1% vs. 16.1%, P=0.03), whereas there were no differences between the 2 groups after both BMS implantation and N-DES implantation. The difference in the percent diameter stenosis from mid-term to late-term follow-up was significantly higher in the VSA group than non-VSA group (10.0% vs. 2.3%, P=0.045) after SES implantation, whereas there were no differences between the 2 groups after both BMS implantation and N-DES implantation.

CONCLUSIONS

The impact of VSA on clinical and angiographic outcomes was observed only in SES implantation, but not after N-DES or BMS implantation.

Safety of bailout stenting after paclitaxel-coated balloon angioplasty

BACKGROUND

Bailout stenting after suboptimal paclitaxel-coated balloon (PCB) angioplasty is required in up to 28% of cases. We sought to compare the safety of bailout stenting with drug-eluting stents (DES) compared with the more established combination of PCB with bare metal stents (BMS).

METHODS

We retrospectively evaluated all patients who had stents implanted owing to suboptimal PCB angioplasty results between January 2010 and April 2015. Endpoints analyzed were major adverse cardiac events (MACE) - defined as cardiovascular death, nonfatal myocardial infarction (MI), and target lesion revascularization (TLR) - as well as major and minor bleeding.

RESULTS

Baseline clinical characteristics were comparable with a high proportion of diabetics in both groups (50.0% vs. 45.8%, p = 0.74). BMS and DES sizes were similar (mean diameter 2.72 ± 0.50 mm vs. 2.89 ± 0.56 mm, p = 0.20, length 25.22 ± 13.47 mm vs. 28.08 ± 9.08 mm, p = 0.47). Outcomes were comparable at the end of 1 year (MACE 12.2% vs. 9.5%, p = 1.00, TLR 6.1% vs. 4.8%, p = 1.00, MI 0% vs. 4.8%, p = 0.30). There was no case of stent thrombosis or major bleeding, and the rates of minor bleeding were similar (4.2% vs. 4.8%, p = 1.00).

CONCLUSION

Our initial experience using DES instead of BMS as a bailout after suboptimal PCB results shows that the procedure is safe and effective at 1 year.

[Measurement of fractional flow reserve in patients with severe aortic stenosis: A valid test?]

A 54-year-old woman was hospitalized for an acute pulmonary oedema revealing a severe aortic stenosis (AS) associated with an aortic aneurysm and a left ventricular hypertrophy (LVH). The coronary angiography found an equivocal left main lesion. Fractional flow reserve (FFR) showed hemodynamic significance (FFR=0.78) and optical coherence tomography confirmed this result with a minimal lumen area of 4.9mm². FFR-guided percutaneous intervention is reported to improve outcome in patients with stable coronary disease. However, only few data are available in cases of AS. In this condition, secondary LVH is associated with microcirculatory dysfunction, which interferes with optimal hyperemia. An elevated right atrial pressure could also modify FFR measurement. This risk of underestimation of a coronary lesion in patients with severe AS has to be taken into consideration in clinical practice.

Relationship between coronary calcium score and high-risk plaque/significant stenosis

AIM

To investigate the relationship between coronary calcium score (CCS) and vulnerable plaque/significant stenosis using coronary computed tomographic angiography (CCTA).

METHODS

CCTA was performed in 651 patients and these patients were divided into the four groups (CCS 0, 1-100, 101-400 and > 400). We studied the incidence of high-risk plaque, including positive remodeling, low attenuation plaque, spotty calcification, and napkin-ring sign, and significant stenosis in each group.

RESULTS

High-risk plaque was found in 1.3%, 10.1%, 13.3% and 13.4% of patients with CCS 0, 1-100, 101-400 and > 400, respectively (P < 0.001). The difference was only significant for patients with zero CCS. The incidence of significant stenosis was 0.6%, 7.6%, 13.3% and 26.9% for each patient group, respectively (P < 0.001), which represented a significant stepwise increase as CCS increased. The combined incidence of high-risk plaque and significant stenosis was 1.9%, 17.7%, 26.9% and 40.3% in each patient group, respectively (P < 0.001), again representing a significant stepwise increase with CCS. The rate of major coronary event was 0%, 4.0%, 7.9% and 17.2% in each patient group, respectively (P < 0.001), another significant stepwise increase as CCS increased.

CONCLUSION

Stepwise increased risk of coronary events associated with increasing CCS is caused by increasing incidence of significant stenosis, while that of high-risk plaque remains the same.

[Computed tomography in patients with chronic stable angina : Fractional flow reserve measurement]

Coronary computed tomography angiography (cCTA) has been established for the non-invasive diagnosis of coronary artery disease (CAD). Previous studies demonstrated the high diagnostic accuracy of cCTA, particularly for ruling out CAD. As a known limitation of cCTA a large number of visually significant coronary stenoses are found to be hemodynamically not relevant by invasive fractional flow reserve (FFR). CT-based FFR (CT-FFR) builds on recent advances in computational fluid dynamics and image simulation techniques. Along with CT myocardial perfusion imaging, CT-FFR is a promising approach towards a more accurate estimation of the hemodynamic relevance of coronary artery stenoses. CT-FFR is derived from regular CT datasets without additional image acquisitions, contrast material, or medication. Two CT-FFR techniques can be differentiated. The initial method requires external use of supercomputers and has gained approval for clinical use in the USA. Furthermore, a prototype-software has been introduced which is less computationally demanding via integration of reduced-order models for on-site calculation of CT-FFR. The present article reviews these methods in the context of available study results and meta-analyses. Furthermore, limitations and future concepts of CT-FFR are discussed.

Cholesterol-independent effects of atorvastatin prevent cardiovascular morbidity and mortality in a mouse model of atherosclerotic plaque rupture

Because cholesterol-independent effects of statins are difficult to determine in patients, we studied these pleiotropic effects in apolipoprotein E-deficient (ApoE(-/-)) mice with a mutation in the fibrillin-1 gene (Fbn1(C1039G+/-)). These mice develop exacerbated atherosclerosis and spontaneous plaque ruptures, accompanied by myocardial infarctions (MI) and sudden death. ApoE(-/-)Fbn1(C1039G+/-) mice were fed a Western diet (WD). At week 10 of WD, mice were divided in a control (WD), atorvastatin (10mg/kg/day + WD) and cholesterol withdrawal group (cholW, normal chow). The latter was included to compare the effects of atorvastatin with dietary lipid lowering. Fifteen weeks later, the mice were sacrificed. CholW, but not atorvastatin, reduced plasma cholesterol. Survival increased from 50% to 90% both in cholW and atorvastatin treated mice. CholW as well as atorvastatin treatment increased plaque collagen and fibrous cap thickness, but they did not affect the amount of plaque macrophages and T cells. MMP-2 and MMP-9 activity was significantly lower and the expression of MMP-12, TNF-α and IL-1β was strongly reduced in both treatment groups. Blood monocytes and neutrophils returned to baseline levels (ApoE(-/-) mice before the onset of atherosclerosis). Importantly, atorvastatin but not cholW significantly reduced coronary stenosis (from 50 to 28%) and the occurrence of MI (from 43 to 10%). In conclusion, independent of cholesterol lowering, atorvastatin significantly reduced mortality, plaque vulnerability and inflammation to the same extent as cholW. In addition, atorvastatin but not cholW reduced coronary stenosis and the occurrence of MI. These data unequivocally illustrate the significance of the pleiotropic effects of atorvastatin in the prevention of cardiovascular morbidity and mortality.

Limitations and Pitfalls of Fractional Flow Reserve Measurements and Adenosine-Induced Hyperemia

Coronary hemodynamic measurements provide a critical tool to assess the ischemic potential of coronary stenoses. Fractional flow reserve (FFR) is a reliable method to relate translesional coronary pressures to hyperemic myocardial blood flow. Although a basic understanding in FFR can be quickly achieved, many of the nuances and potential pitfalls require special attention. The authors discuss the practical setup of coronary pressure measurement, the most common pitfalls in technique and ways to avoid them, and the limitations of available pharmacologic hyperemic methods.

Coronary stenosis risk analysis following Hodgkin lymphoma radiotherapy: A study based on patient specific artery segments dose calculation

BACKGROUND AND PURPOSE

The dose effect-effect relationship for cardiac diseases following radiotherapy suffers from uncertainties. Three dimensional coronary artery (CA) dose calculation after mediastinal Hodgkin lymphoma radiotherapy was performed, using the patient's coronary CT angiography (CCTA), and the relationship between the coronary arteries' radiation doses and the risk of stenosis was estimated.

MATERIALS AND METHODS

Radiotherapy simulation CT scans and CCTAs of patients treated for a mediastinal Hodgkin lymphoma were used to merge thoracic and detailed cardiovascular anatomies. Radiation treatment parameters were used to estimate CA radiation doses. Twenty-one patients without coronary stenosis (controls) were matched with twelve patients with stenosis (cases). CA segments were considered as sub-volumes of interest. Radiation doses to stenotic segments were compared with those received by normal segments (from cases and controls) using a logistic regression.

RESULTS

In eleven cases out of twelve, the highest of the coronary dose distribution was on a damaged segment. Logistic regression with CA segments yielded an odds ratio associated with the risk of coronary stenosis of 1.049 per additional gray with the CA segment median dose (95% confidence interval, 1.004-1.095; p-value <0.05).

CONCLUSION

The CA segment dose significantly increased the risk of stenosis on the segment. Such personalized CA dose calculations on larger cohorts are expected to improve the understanding of the cardiovascular radiation dose-effect relationship.

Chronic intermittent mental stress promotes atherosclerotic plaque vulnerability, myocardial infarction and sudden death in mice

Vulnerable atherosclerotic plaques are prone to plaque rupture leading to acute cardiovascular syndromes and death. Elucidating the risk of plaque rupture is important to define better therapeutic or preventive strategies. In the present study, we investigated the effect of chronic intermittent mental stress on atherosclerotic plaque stability and cardiovascular mortality in apolipoprotein E-deficient (ApoE(-/-)) mice with a heterozygous mutation in the fibrillin-1 gene (Fbn1(C1039G+/)(-)). This mouse model displays exacerbated atherosclerosis with spontaneous plaque ruptures, myocardial infarction and sudden death, when fed a Western-type diet (WD). Female ApoE(-/-)Fbn1(C1039G+/-) mice were fed a WD for up to 25 weeks. After 10 weeks WD, mice were divided in a control (n = 27) and mental stress (n = 29) group. The chronic intermittent mental stress protocol consisted of 3 triggers: water avoidance, damp bedding and restraint stress, in a randomly assigned order lasting 6 h every weekday for 15 weeks. Chronic intermittent mental stress resulted in a significant increase in the amount of macrophages in atherosclerotic plaques of the proximal ascending aorta, whereas type I collagen and fibrous cap thickness were decreased. The coronary arteries of mental stress-treated mice showed larger plaques, more stenosis, and an increased degree of perivascular fibrosis. Moreover, myocardial infarctions occurred more frequently in the mental stress group. As compared to the control group, the survival of stressed ApoE(-/-)Fbn1(C1039G+/-) mice decreased from 67% to 52% at 25 weeks WD, presumably due to myocardial infarctions. In conclusion, chronic intermittent mental stress promotes plaque instability, myocardial infarctions, and mortality of ApoE(-/-)Fbn1(C1039G+/-) mice.

Comparison of instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR)--first real world experience

BACKGROUND

The instantaneous wave-free ratio (iFR) is a new adenosine-independent index of coronary stenosis severity. Most published data have been based on off-line analyses of pressure recordings in a core laboratory. We prospectively compared real-time iFR and fractional flow reserve (FFR) measurements.

METHODS AND RESULTS

iFR and FFR were measured in 151 coronary stenoses in 108 patients. Repeated iFR measurements were technically simple, showed excellent agreement [rs=0.99; p<0.0001], and the mean difference between consecutive iFR values was 0.0035 (limits of agreement: -0.019, 0.026). Mean iFR showed a significant correlation with FFR [rs=0.81; p<0.0001]. Receiver-operating characteristic analysis identified an optimal iFR cut-off value of 0.896 for categorization based on an FFR cut-off value 0.8. We compared two different iFR-based diagnostic strategies (iFR-only and hybrid iFR-FFR) with standard FFR: The iFR-only strategy showed good classification agreement (83.4%) with standard FFR. Use of the hybrid iFR-FFR strategy, assessing lesions in an iFR-gray zone of 0.86-0.93 by FFR, improved classification accuracy to 94.7%, and diagnosis would have been established in 61% of patients without adenosine-induced hyperemia. Notably, both iFR and FFR values were significantly higher in the posterior coronary vessels.

CONCLUSIONS

Real-time iFR measurements are easily performed, have excellent diagnostic performance and confirm available off-line core laboratory data. The excellent agreement between repeated iFR measurements demonstrates the reliability of single measurements. Combining iFR with FFR in a hybrid strategy enhances diagnostic accuracy, exposing fewer patients to adenosine. Overall, iFR is a promising method, but still requires prospective clinical endpoint trial evaluation.

Transthoracic Doppler for detection of stenoses in the three main coronary arteries by use of stenotic to prestenotic velocity ratio and aliased coronary flow

AIMS

Our aim was to determine the feasibility and accuracy of diagnosing significant coronary artery stenoses using peak stenotic to prestenotic velocity ratio (pSPVR) measurements when compared with results from quantitative coronary angiography and coronary flow velocity reserve (CFVR) assessed by transthoracic echocardiography (TTE).

METHODS AND RESULTS

One hundred and eight patients scheduled for coronary angiography were studied using transthoracic Doppler echocardiography. Stenoses were identified by local colour aliasing by colour flow Doppler, and further evaluated by pSPVR, using a pSPVR of ≥2.0 as a cut-off for significant stenosis. When pSPVR could not be measured, local mosaic coronary flow pattern at Nyquist limit ≥0.48 m/s was used. Sixty-five lesions suggestive of stenosis were found by TTE. Combining findings of pSPVR ≥2.0 and local mosaic flow at Nyquist limit ≥0.48 m/s, the sensitivity and specificity of demonstrating significant stenoses (diameter stenosis, 50-99%) in the left main coronary artery (LM), left anterior descending coronary (LAD), left circumflex coronary (Cx), and right coronary artery (RCA) were 75 and 98%, 74 and 95%, 40 and 87%, and 34 and 98%, respectively. The pSPVR did not differ significantly between arteries with reduced and normal CFVR, with a cut-off of CFVR <2.0.

CONCLUSIONS

Findings of pSPVR ≥2.0 or localized colour flow aliasing are useful in the non-invasive diagnosis of significant coronary disease in the three main coronary arteries, with high specificity for detecting significant stenoses. These findings showed high sensitivity for identifying significant stenoses in the LM and LAD, but showed lower ability to detect those lesions in the Cx and RCA.

Coronary Atherosclerosis and Interventional Cardiology

The atherosclerotic process in coronary arteries begins with endothelial dysfunction and may provoke thrombotic total occlusion and myocardial infarction. In this state-of-the-art review, we discuss recent evidence of atheroslerosis, vulnerable plaque, and hemodynamic changes in the coronary tree, as well as the current techniques we implement in the catheterization lab to evaluate coronary stenosis. It is clear that atherosclerosis is a chronic inflammatory condition with several consequences in the coronary tree, however, we are able now to characterize the plaque and to select the appropriate treatment for many patients.

Plasma oxysterol level in patients with coronary artery stenosis and its changes in response to the treatment with atorvastatin

BACKGROUND

Considering the increasing incidence of coronary artery stenosis and its related complications, the importance of its etiology and inconsistent reports we aimed to determine the relationship between oxysterol, serum levels and severity of coronary atherosclerosis and effect of statins onoxysterol.

METHODS

A total of 85 patients referred to Taleghani Hospital, Tehran, Iran during 2011-2012 withcoronary artery stenosis more than 75%, as determined by angiography, participated in the currentstudy. Their demographic information and history of smoking and taking atorvastatin was carefullyrecorded. Two milliliters of venous blood was obtained from each patient. The serum oxysterol levelof samples was measured using the enzyme-linked immunosorbent assay (ELISA) method. Statisticalanalysis was performed using SPSS v.19.

RESULTS

Eighty five patients completed the study. Mean age of patients was 64.4 years; 51 (60%)were male; 55 (68%) had acute coronary syndrome and 30 (32%) had chronic stable angina.Mean±SD of plasma level of oxysterol was 24.8±0.2 pmol/ml. The normal range of oxysterol levelwas 13pmol/ml. Mean±SD of plasma oxysterol level in patients under statin therapy was 24.4±2.1pmol/ml. In patients without receiving statins, plasma oxysterol level was 26.38±1.6pmol/ml.

CONCLUSION

Findings of the present study indicated significant correlation between serum oxysteroland severity of coronary artery stenosis. It also demonstrated that receiving atorvastatin is associatedwith significant reduction of plasma oxysterol level.

Patients ≥ 75 years with acute coronary syndrome but without critical epicardial coronary disease: prevalence, characteristics, and outcome

OBJECTIVE

Absence of significant epicardial coronary artery disease (CAD) in patients with acute onset of chest pain and elevation of myocardial necrosis markers is occasionally observed. The aim of this study was to analyse the clinical characteristics and outcome of such patients with advanced age.

METHODS

We retrospectively analysed 4,311 patients with acute onset of chest pain plus necrosis marker elevation. Two hundred and seventy two patients without CAD on angiogram (6.3%) were identified. Out of them, 50 (1.2%) patients ≥ 75 years (Group I) were compared with (1) 222 acute coronary syndrome (ACS) patients without CAD on angiogram < 75 years (Group II), and (2) 610 consecutive patients ≥ 75 years with Non-ST-elevation Myocardial Infarction (NSTEMI) undergoing percutaneous coronary intervention (Group III).

RESULTS

Group I compared to Group III patients made up for more females (64.0% vs. 49.2%; P < 0.0001), and had more severe anginal symptoms on presentation [Canadian Cardiovascular Society (CCS) class I/II, 26.0% vs. 49.8%; P = 0.02]. Group I patients also had lower troponin levels (0.62 ± 0.8 ng/mL vs. 27 ± 74 ng/mL; P < 0.02), lower leukocyte count (9.4 ± 3.13 × 10(9) vs. 12 ± 5.1 × 10(9); P = 0.001) and better preserved left ventricular function (56.7% ± 14.3% vs. 45% ± 11%; P < 0.0001). Event-free survival (cardiac death, myocardial infarction, recurrent angina, and re-hospitalisation) was more frequent in Group I and II patients compared to Group III patients (64.9%, 66.7%, and 41.6%, respectively; P < 0.0001).

CONCLUSIONS

ACS in patients ≥ 75 years without CAD is very infrequent, associated with a (1) similar outcome compared to ACS patients < 75 years without CAD, and (2) significant better outcome compared to NSTEMI patients ≥ 75 years.

Hemodialysis immediately after cardiac catheterization is a risk factor for intradialytic hypotension

Many hemodialysis clinicians have noticed that patients frequently develop intradialytic hypotension (IDH) immediately after cardiac catheterization (CC). However, precise data about the incidence of IDH immediately after CC are scarce. This study involved a single-center, retrospective, cross-sectional design. We reviewed the medical records of all HD patients who underwent CC between January 2009 and March 2012 at Hiroshima Prefectural Hospital. IDH was defined as a fall of systolic blood pressure of more than 20 mm Hg or a fall of mean blood pressure of more than 10 mm Hg, with symptoms according to the K/DOQI criteria. Data on a total of 112 patients were obtained: 64 patients commenced HD immediately after CC (IA group) and 48 patients underwent HD on the day after CC (ND group). The overall incidence of IDH was 34% (38/112). The incidence of IDH was significantly higher in the IA group than in the ND group (27/64, 42% vs. 11/48, 23%; P < 0.05). Multivariate logistic regression analysis showed that IA (odds ratio, 5.39; 95% confidence interval, 1.76 to 16.49; P < 0.01), coronary stenosis (odds ratio, 4.16; 95% confidence interval, 1.49 to 11.64; P < 0.05) were independently associated with IDH. This study revealed that HD immediately after CC is associated with a higher incidence of IDH. Clinicians should consider that HD following CC be scheduled for the next day, especially in patients with coronary stenosis.

The instantaneous wave-free ratio (iFR) for evaluation of non-culprit lesions in patients with acute coronary syndrome and multivessel disease

BACKGROUND

Adenosine administration is currently required for evaluation of stenosis severity with fractional flow reserve (FFR). The instantaneous wave-free ratio (iFR) was recently introduced as an adenosine-free alternative in patients with stable CAD. The aim of the present study was to replicate the findings of previous iFR studies using an independent calculation algorithm and to evaluate the iFR for the assessment of non-culprit vessels in patients with acute coronary syndrome (ACS).

METHODS AND RESULTS

53 patients with ACS (65%) and at least one non-culprit intermediate lesion and 29 (35%) with stable CAD were included. A total of 123 stenoses were evaluated with both FFR and iFR. Classification match of iFR in ACS was not inferior to stable CAD (79.5% in ACS and 84.4% in CAD; p=0.497). Accordingly, no difference was observed in iFR/FFR correlation between ACS and stable CAD (r=0.66 in ACS vs. r=0.69 in CAD). Overall, a significant correlation was found between iFR and FFR (r=0.68; p<0.001) with a good diagnostic efficiency at ROC analysis (area under the curve: 0.87). In addition, neither the localization of the stenosis within the coronary tree (p=0.147) nor the time interval from the acute event (p=0.550) significantly influenced the concordance of iFR with FFR.

CONCLUSIONS

The iFR is a promising method for the assessment of non-culprit lesion severity in patients with acute coronary syndrome.