Mark H.M. Winkens

The Extent of Coronary Atherosclerosis Is Associated With Increasing Circulating Levels of High Sensitive Cardiac Troponin T

Objective—This study explored the relationship between coronary atherosclerotic plaque burden and quantifiable circulating levels of troponin measured with a recently introduced high sensitive cardiac troponin T (hs-cTnT) assay. Methods and Results—Cardiac patients suspected of having coronary artery disease (CAD) but without acute coronary syndrome were studied. Cardiac troponin T levels were assessed using the fifth-generation hs-cTnT assay. All patients (n=615) underwent cardiac computed tomographic angiography (CCTA). On the basis of CCTA, patients were classified as having no CAD or mild (<50% lesion), moderate (50% to 70% lesion), severe (>70% lesion), or multivessel CAD (multiple >70% lesions). As a comparison, high-sensitivity C-reactive protein levels were measured. Progressively increasing hs-cTnT levels were found in patients with mild (median, 4.5 ng/L), moderate (median, 5.5 ng/L), severe (median, 5.7 ng/L), and multivessel (median, 8.6 ng/L) CAD compared with patients without CAD (median, 3.7 ng/L) (all P<0.01). For high-sensitivity C-reactive protein and N-terminal pro-B-type natriuretic peptide, no such relationship was observed. In patients without CAD, 11% showed hs-cTnT levels in the highest quartile, compared with 62% in the multivessel disease group (P<0.05). Multivariance analysis identified hs-cTnT as an independent risk factor for the presence of CAD. Conclusion—In patients without acute coronary syndrome, even mild CAD is associated with quantifiable circulating levels of hs-cTnT.

Thrombin generation in patients with a first acute myocardial infarction

Summary.  Background: Despite improved treatment options, myocardial infarction is still an important cause of morbidity and mortality. One of the contributing mechanisms in the acute myocardial infarction (AMI) is plasma hypercoagulability. Methods: We investigated hypercoagulability in 135 (first) patients with AMI using thrombin generation (TG) testing. TG testing was performed in plasmas, drawn upon admission and before medication administration, and subsequently after 4 days, 3 and 6 months. Further, we evaluated determinants of thrombin generation using multiple regression analysis of major coagulation proteins and inhibitors. Admission TG results were also related to 1‐year outcome: cardiovascular death, recurrent myocardial infarction, a second coronary intervention [percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG)] and ischemic stroke. Results: At day 0, the TG parameters peak height, endogenous thrombin potential (ETP) and lag time were increased compared with a reference population. Peak height and lag time stayed persistently increased in patients. The lowest half of the ETP values was statistically not significantly associated with an occurrence of endpoints. The lowest half of the ETP values combined with the upper half of the D‐dimer values were associated with endpoints; odds ratio 5.8 (1.1–30.7). Tissue factor pathway inhibitor (TFPI) seems to be an important determinant of TG in AMI and healthy persons. Conclusions: TG reflects acute hypercoagulability during AMI and partly also in the 6‐month period after the acute event. TG shows a trend of an inverse association with risk of recurrent ischemic cardiovascular complications. Unraveling mechanisms in TG might improve our understanding of the pathophysiology of AMI and direct future improvements in medical care.

Molecular Imaging of Macrophage Cell Death for the Assessment of Plaque Vulnerability

The ability to identify atherosclerotic plaques that are prone to rupture, also called vulnerable plaques, may provide a major step forward in the recognition of patients that have a high risk of developing acute myocardial infarction. Current clinical risk profiling algorithms, such as the Framingham and Procam risk scores, have reasonable predictive value in the assessment of the 10 year risk. These clinical risk profiling scores typically classify patients into low risk (10-year risk, less than 5%), intermediate risk (5% to 20% risk), and high risk (greater than 20%). The challenge to imagers is to identify the risk that is beyond 2% yearly risk. Molecular imaging may help identify plaque inflammation and apoptosis of inflammatory cells, which are obligatory components of the plaque instability. These processes offer specific biological targets that can potentially be exploited to obtain biological information on atherosclerosis development in the individual patient.

Performance of angiographic, electrocardiographic and MRI methods to assess the area at risk in acute myocardial infarction

Objective Validation of methods to assess the area at risk (AAR) in patients with ST elevation myocardial infarction is limited. A study was undertaken to test different AAR methods using established physiological concepts to provide a reference standard. Main outcome measured In 78 reperfused patients with first ST elevation myocardial infarction, AAR was measured by electrocardiographic (Aldrich), angiographic (Bypass Angioplasty Revascularization Investigation (BARI), APPROACH) and cardiovascular magnetic resonance methods (T2-weighted hyperintensity and delayed enhanced endocardial surface area (ESA)). The following established physiological concepts were used to evaluate the AAR methods: (1) AAR size is always ≥ infarct size (IS); (2) in transmural infarcts AAR size=IS; (3) correlation between AAR size and IS increases as infarct transmurality increases; and (4) myocardial salvage ((AAR-IS)/AAR×100) is inversely related to infarct transmurality. Results Overall, 65%, 87%, 76%, 87% and 97% of patients using the Aldrich, BARI, APPROACH, T2-weighted hyperintensity and ESA methods obeyed the concept that AAR size is ≥IS. In patients with transmural infarcts (n=22), Bland–Altman analysis showed poor agreement (wide 95% limits of agreement) between AAR size and IS for the BARI, Aldrich and APPROACH methods (95% CI −22.9 to 29.6, 95% CI −28.3 to 21.3 and 95% CI −16.9 to 20.0, respectively) and better agreement for T2-weighted hyperintensity and ESA (95% CI −6.9 to 16.6 and 95% CI −4.3 to 18.0, respectively). Increasing correlation between AAR size and IS with increasing infarct transmurality was observed for the APPROACH, T2-weighted hyperintensity and ESA methods, with ESA having the highest correlation (r=0.93, p<0.001). The percentage of patients within a narrow margin (±30%) of the inverse line of identity between salvage extent and infarct transmurality was 56%, 76%, 65%, 77% and 92% for the Aldrich, BARI, APPROACH, T2-weighted hyperintensity and ESA methods, respectively, where higher percentages represent better concordance with the concept that the extent of salvage should be inversely related to infarct transmurality. Conclusions For measuring AAR, cardiovascular magnetic resonance methods are better than angiographic methods, which are better than electrocardiographic methods. Overall, ESA performed best for measuring AAR in vivo.

Combined use of exercise electrocardiography, coronary calcium score and cardiac CT angiography for the prediction of major cardiovascular events in patients presenting with stable chest pain

BACKGROUND The usual diagnostic work-up of chest pain patients includes clinical risk profiling and exercise-ECG, possibly followed by additional tests. Recently cardiac computed tomographic angiography (CCTA) has been employed. We evaluated the prognostic value of the combined use of exercise-ECG and CCTA for the development of cardiovascular endpoints. METHODS In 283 patients (143 male, mean age 54 ± 10 years) with intermediate pre-test probability for coronary artery disease presenting with stable chest pain, exercise-ECG, CCTA and calcium score were performed. Patients were followed-up for combined endpoint of acute coronary syndrome (ACS) and revascularization. RESULTS After a median follow-up of 769 days (interquartile range 644-1007), 6 ACS and 9 revascularizations were recorded. A positive exercise-ECG predicted for the combined endpoint, [hazard ratio (HR) 5.14 (95% confidence interval (CI) 1.64-16.13), p=0.005], as well as a positive calcium score [HR 4.59 (95% CI 1.30-16.28), p=0.02] and a ≥ 50% stenosis on CCTA [HR 45.82 (95% CI 6.02-348.54), p<0.001]. ROC-analysis showed an area under the curve (AUC) of 0.79 (95% CI 0.67-0.90) for exercise-ECG, which increased significantly when CCTA was added: 0.91 (95% CI; 0.86-0.97; p=0.006). Multivariable Cox regression showed exercise-ECG predicted independently [HR 3.6, (95% CI 1.1-11.2), p=0.03], as well as CCTA [HR 31.4 (95% CI 4.0-246.6), p=0.001], but not calcium score [HR 0.6 (95% CI 0.2-2.3), p=0.5]. CONCLUSIONS The combined subsequent use of exercise-ECG for functional information and CCTA for anatomical information provides a high diagnostic yield in stable chest pain patients with an intermediate pre-test probability for coronary artery disease.

High-sensitivity cardiac troponin t: Risk stratification tool in patients with symptoms of chest discomfort

Background Recent studies have demonstrated the association between increased concentrations of high-sensitivity cardiac troponin T (hs-cTnT) and the incidence of myocardial infarction, heart failure, and mortality. However, most prognostic studies to date focus on the value of hs-cTnT in the elderly or general population. The value of hs-cTnT in symptomatic patients visiting the outpatient department remains unclear. The aim of this study was to investigate the prognostic value of hs-cTnT as a biomarker in patients with symptoms of chest discomfort suspected for coronary artery disease and to assess its additional value in combination with other risk stratification tools in predicting cardiac events. Methods We studied 1,088 patients (follow-up 2.2±0.8 years) with chest discomfort who underwent coronary calcium scoring and coronary CT-angiography. Traditional cardiovascular risk factors and concentrations of hs-cTnT, N-terminal pro-brain-type natriuretic peptide (NT-proBNP) and high-sensitivity C-reactive protein (hsCRP) were assessed. Study endpoint was the occurrence of late coronary revascularization (>90 days), acute coronary syndrome, and cardiac mortality. Results Hs-cTnT was a significant predictor for the composite endpoint (highest quartile [Q4]>6.7 ng/L, HR 3.55; 95%CI 1.88–6.70; P<0.001). Survival analysis showed that hs-cTnT had significant predictive value on top of current risk stratification tools (Chi-square change P<0.01). In patients with hs-cTnT in Q4 versus <Q4, a 2- to 3-fold increase in cardiovascular risk was noticed, either when corrected for high or low Framingham risk score, coronary calcium scoring, or CT-angiography assessment (HR 3.11; 2.73; 2.47; respectively; all P<0.01). This was not the case for hsCRP and NT-proBNP. Conclusions Hs-cTnT is a useful prognostic biomarker in patients with chest discomfort suspected for coronary artery disease. In addition, hs-cTnT was an independent predictor for cardiac events when corrected for cardiovascular risk profiling, calcium score and CT-angiography results.

Relation between Mild to Moderate Chronic Kidney Disease and Coronary Artery Disease Determined with Coronary CT Angiography

Background Both end-stage and milder stages of chronic kidney disease (CKD) are associated with an increased risk of adverse cardiovascular events. Several studies found an association between decreasing renal function and increasing coronary artery calcification, but it remains unclear if this association is independent from traditional cardiovascular risk factors. Therefore, the aim of this study was to investigate whether mild to moderate CKD is independently associated with coronary plaque burden beyond traditional cardiovascular risk factors. Methods A total of 2,038 patients with symptoms of chest discomfort suspected for coronary artery disease underwent coronary CT-angiography. We assessed traditional risk factors, coronary calcium score and coronary plaque characteristics (morphology and degree of luminal stenosis). Patients were subdivided in three groups, based on their estimated glomerular filtration rate (eGFR) Normal renal function (eGFR ≥90 mL/min/1.73 m2); mild CKD (eGFR 60–89 mL/min/1.73 m2); and moderate CKD (eGFR 30–59 mL/min/1.73 m2). Results Coronary calcium score increased significantly with decreasing renal function (P<0.001). Coronary plaque prevalence was higher in patients with mild CKD (OR 1.83, 95%CI 1.52–2.21) and moderate CKD (OR 2.46, 95%CI 1.69–3.59), compared to patients with normal renal function (both P<0.001). Coronary plaques with >70% luminal stenosis were found significantly more often in patients with mild CKD (OR 1.67 (95%CI 1.16–2.40) and moderate CKD (OR2.36, 95%CI 1.35–4.13), compared to patients with normal renal function (both P<0.01). After adjustment for traditional cardiovascular risk factors, the association between renal function and the presence of any coronary plaque as well as the association between renal function and the presence of coronary plaques with >70% luminal stenosis becomes weaker and were no longer statistically significant. Conclusion Although decreasing renal function is associated with increasing extent and severity of coronary artery disease, mild to moderately CKD is not independently associated with coronary plaque burden after adjustment for traditional cardiovascular risk factors.

Imaging of Arrhythmogenic Right Ventricular Cardiomyopathy

Clinical diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC) remains challenging, especially in the early stages of the disease, and relies on Task Force criteria that encompass electrocardiographic, morphological (fibrofatty infiltration, wall thinning), and functional abnormalities (focal or global contraction abnormalities, right ventricle [RV] dilatation, and aneurysms).1 A 47-year-old male ARVC patient with a known plakophilin gene mutation and electrocardiographic signs of ARVC (T-wave inversion and epsilon waves in the right precordial leads, Figure, A, arrows) was scheduled for cardiac magnetic resonance and 64-slice cardiac computed tomographic imaging (MDCT) …