Electrocardiogram-based mortality prediction in patients with COVID-19 using machine learning.

BACKGROUND AND PURPOSE: The electrocardiogram (ECG) is frequently obtained in the work-up of COVID-19 patients. So far, no study has evaluated whether ECG-based machine learning models have added value to predict in-hospital mortality specifically in COVID-19 patients. METHODS: Using data from the CAPACITY-COVID registry, we studied 882 patients admitted with COVID-19 across seven hospitals in the Netherlands. Raw format 12-lead ECGs recorded within 72 h of admission were studied. With data from five hospitals (n = 634), three models were developed: (a) a logistic regression baseline model using age and sex, (b) a least absolute shrinkage and selection operator (LASSO) model using age, sex and human annotated ECG features, and (c) a pre-trained deep neural network (DNN) using age, sex and the raw ECG waveforms. Data from two hospitals (n = 248) was used for external validation. RESULTS: Performances for models a, b and c were comparable with an area under the receiver operating curve of 0.73 (95% confidence interval [CI] 0.65-0.79), 0.76 (95% CI 0.68-0.82) and 0.77 (95% CI 0.70-0.83) respectively. Predictors of mortality in the LASSO model were age, low QRS voltage, ST depression, premature atrial complexes, sex, increased ventricular rate, and right bundle branch block. CONCLUSION: This study shows that the ECG-based prediction models could be helpful for the initial risk stratification of patients diagnosed with COVID-19, and that several ECG abnormalities are associated with in-hospital all-cause mortality of COVID-19 patients. Moreover, this proof-of-principle study shows that the use of pre-trained DNNs for ECG analysis does not underperform compared with time-consuming manual annotation of ECG features.

COVID-19-mediated patient delay caused increased total ischaemic time in ST-segment elevation myocardial infarction.

BACKGROUND: The current study aimed to evaluate changes in treatment delay and outcome for ST-segment elevation myocardial infarction (STEMI) in the Netherlands during the first coronavirus disease 2019 (COVID-19) outbreak, thereby comparing regions with a high and low COVID-19 hospitalisation rate. METHODS: Clinical characteristics, STEMI timing variables, 30-day all-cause mortality and cardiovascular complications of all consecutive patients admitted for STEMI from 1 January to 30 June in 2020 and 2019 to six hospitals performing a high volume of percutaneous coronary interventions were collected retrospectively using data from the Netherlands Heart Registry, hospital records and ambulance report forms. Patient delay, pre-hospital delay and door-to-balloon time before and after the outbreak of COVID-19 were compared to the equivalent periods in 2019. RESULTS: A total of 2169 patients were included. During the outbreak median total treatment delay significantly increased (2 h 51 min vs 2 h 32 min; p = 0.043) due to an increased patient delay (1 h 20 min vs 1 h; p = 0.030) with more late presentations > 24 h (1.1% vs 0.3%) in 2020. This increase was particularly evident during the peak phase of COVID-19 in regions with a high COVID-19 hospitalisation rate. During the peak phase door-to-balloon time was shorter (38 min vs 43 min; p = 0.042) than in 2019. All-cause 30-day mortality was comparable in both time frames (7.8% vs 7.3%; p = 0.797). CONCLUSIONS: During the outbreak of COVID-19 patient delay caused an increase in total ischaemic time for STEMI, with a more pronounced delay in high-endemic regions, stressing the importance of good patient education during comparable crisis situations.

Association between public media and trends in new acute coronary syndrome presentations during the first COVID­19 wave in the Netherlands.

BACKGROUND: We aimed to evaluate the association between public media and trends in new presentations of acute coronary syndrome (ACS) during the first wave of the coronavirus disease 2019 (COVID­19) in the Netherlands. METHODS: New ACS presentations per week in 73 hospitals during the first half of 2019 and 2020 were retrieved from the national organisation Dutch Hospital Data and incidence rates were calculated. Stratified analyses were performed by region, type of ACS and patient characteristics. RESULTS: After the first confirmed COVID­19 case and during lockdown, numbers declined by up to 41% (95% confidence interval (CI): 36-47%) compared to 2019. This reduction was more pronounced for non-ST-segment elevation myocardial infarction (NSTEMI) (48%; 95% CI: 39-55%) and unstable angina (UA; 50%; 95% CI: 40-59%) than for STEMI (34%; 95% CI: 23-43%). There was no association between ACS and COVID­19 incidence rate per region. After the steep decline, a public campaign encouraged patients not to postpone hospital visits. Numbers then increased, without a rebound effect. Trends were similar irrespective of sex, age or socio-economic status. During the outbreak, compared to coronary artery bypass graft procedures, relatively more (acute) percutaneous coronary interventions for NSTEMI and UA were performed. CONCLUSION: New ACS presentations decreased by up to 41%. Lockdown measures and public campaigns, rather than COVID­19 incidence, were associated with significant changes in new ACS presentations. Even though causality cannot be established, this emphasises the role of the public media and healthcare organisations in informing patients to prevent underdiagnoses of ACS and associated health damage.

How often and to what extent do admitted COVID-19 patients have signs of cardiac injury?

BACKGROUND: COVID-19 can cause myocardial injury in a significant proportion of patients admitted to the hospital and seems to be associated with worse prognosis. The aim of this review was to study how often and to what extent COVID-19 causes myocardial injury and whether this is an important contributor to outcome with implications for management. METHODS: A literature search was performed in Medline and Embase. Myocardial injury was defined as elevated cardiac troponin (cTn) levels with at least one value > 99th percentile of the upper reference limit. The primary outcome measure was mortality, whereas secondary outcome measures were intensive care unit (ICU) admission and length of hospital stay. RESULTS: Four studies and one review were included. The presence of myocardial injury varied between 9.6 and 46.3%. Myocardial injury was associated with a higher mortality rate (risk ratio (RR) 5.54, 95% confidence interval (CI) 3.48-8.80) and more ICU admissions (RR 3.78, 95% CI 2.07-6.89). The results regarding length of hospital stay were inconclusive. CONCLUSION: Patients with myocardial injury might be classified as high-risk patients, with probably a higher mortality rate and a larger need for ICU admission. cTn levels can be used in risk stratification models and can indicate which patients potentially benefit from early medication administration. We recommend measuring cTn levels in all COVID-19 patients admitted to the hospital or who deteriorate during admission.

Long-term prognostic value of quantitative myocardial perfusion in patients with chest pain and normal coronary arteries.

BACKGROUND: Patients with chest pain and no obstructive coronary artery disease have shown a high incidence of major adverse cardiovascular events (MACE). We evaluated the role of absolute myocardial perfusion quantification in predicting all-cause mortality and MACE during long-term follow-up in this group of patients. METHODS: We studied 79 patients who underwent Nitrogen-13 ammonia PET for quantification of global myocardial blood flow (MBF) and myocardial flow reserve (MFR) due to suspected impaired myocardial perfusion. Patients with coronary artery disease (i.e., > 30% stenosis in one or more coronary arteries) were excluded. We assessed all-cause mortality and MACE. MACE was defined as the composite incidence of death, myocardial infarction (MI), or hospitalization due to heart failure. RESULTS: Median follow-up was 8 (IQR: 3-14) years. Univariate Cox regression showed that only MFR (P = 0.01) was a predictor of all-cause mortality. Univariate Cox regression analysis showed that both MFR and Stress MBF were predictors of the composite endpoint of MACE (P < 0.001 and P = 0.01, respectively). CONCLUSION: Quantitative assessment of myocardial perfusion may predict all-cause mortality and MACE in patients with chest pain and normal coronary arteries in the long-term follow-up.

Relationship between epicardial adipose tissue and subclinical coronary artery disease in patients with extra-cardiac arterial disease.

OBJECTIVE: Epicardial adipose tissue (EAT) and mediastinal adipose tissue (MAT) are linked to coronary artery disease (CAD). The association between EAT, MAT, and severity of CAD in known extra-cardiac arterial disease was investigated. DESIGN AND METHODS: Sixty-five cardiac asymptomatic patients (mean age 65 ± 8 years, 69% male) with peripheral arterial disease, carotid stenosis, or aortic aneurysm underwent coronary computed tomography angiography. Patients were divided into non-significant (<50% stenosis, N = 35), single vessel (N = 15) and multi-vessel CAD (N = 15). EAT and MAT were quantified on computed tomography images using volumetric software. RESULTS: Subgroups did not significantly differ by age, gender, or cardiovascular risk factors. Median EAT was 99.5, 98.0, and 112.0 cm(3) (P = 0.38) and median MAT was 66.0, 90.0, and 81.0 cm(3) (P = 0.53) for non-significant, single vessel, and multi-vessel CAD, respectively. In age- and gender-adjusted analysis, only EAT was significantly associated with CAD (odds ratio [OR] 1.12 [95% confidence interval, 1.01-1.25] per 10 cm(3) increase in EAT; P = 0.04). This remained in multivariate-adjusted analysis (OR 1.21 [1.04-1.39]; P = 0.01). CONCLUSIONS: In patients with known extra-cardiac arterial disease, CAD is correlated with EAT, but not with MAT. These results suggest that EAT has a local effect on coronary atherosclerosis, apart from the endocrine effect of visceral fat.

Calcification as a risk factor for rupture of abdominal aortic aneurysm.

OBJECTIVES: Abdominal aortic aneurysm (AAA) is a major cause of death in developed countries. The AAA diameter is still the only validated prognostic measure for rupture, and therapeutic interventions are initiated accordingly. This still leads to unnecessary interventions in some cases or unidentified impending ruptures. Vascular calcification has been validated abundantly as a risk factor in the cardiovascular field and may strengthen the rupture risk assessment of the AAA. With this study we aim to assess the correlation between AAA calcification and rupture risk in a retrospective unmatched case-control population. METHODS: A database of 334 AAA patients was evaluated. Three groups were formed: elective (eAAA; n = 233), ruptured (rAAA; n = 73) and symptomatic non-ruptured (sAAA; n = 28) AAA patients. The Abdominal Aortic Calcification-8 score (AAC-8) was used to measure the severity of vascular calcification. RESULTS: The AAA diameter (61 ± 12 mm vs. 74 ± 21 mm; p < .001) and AAC-8 score (3.4 ± 2 points vs. 4.9 ± 2.3 points; p < .001) of the eAAA and the combined rAAA and sAAA groups, respectively, were significantly different after univariate analysis. Multivariate analysis showed that larger AAA diameter (odds ratio [OR]: 1.048/mm increase; 95% confidence interval [CI]: 1.042-1.082; p < .001) and a higher AAC-8 score (OR: 1.34/point increase; 95% CI: 1.19-1.53; p < .001) were significantly associated with development into a sAAA or rAAA. Peripheral artery disease was significantly correlated to eventual elective treatment (OR: 0.39; 95% CI: .15-1; p = .049). CONCLUSION: This study suggests a trend of an increased degree of calcification in symptomatic or even ruptured AAA patients compared with elective AAA patients.

Prevalence of severe subclinical coronary artery disease on cardiac CT and MRI in patients with extra-cardiac arterial disease.

OBJECTIVE: Patients with extra-cardiac arterial disease (ECAD) are at high risk of coronary artery disease (CAD). Prevalence of silent, significant CAD in patients with stenotic or aneurysmal ECAD was examined. Early detection and treatment may reduce CAD mortality in this high-risk group. MATERIALS AND METHODS: ECAD patients without cardiac complaints underwent computed tomography (CT) for calcium scoring, coronary CT angiography (cCTA) if calcium score was 1,000 or under, and adenosine perfusion magnetic resonance imaging (APMR) if there was no left main stenosis. Significant CAD was defined as calcium score over 1,000, cCTA-detected coronary stenosis of at least 50% lumen diameter, and/or APMR-detected inducible myocardial ischemia. In cases of left main stenosis (or equivalent) or myocardial ischemia, patients were referred to a cardiologist. RESULTS: The prevalence of significant CAD was 56.8% (95% CI 47.5 to 66.0). One-hundred and eleven patients were included. Eighty-four patients (76%) had stenotic ECAD, and 27 (24%) had aneurysmal disease. In patients with stenotic ECAD, significant coronary stenosis was present in 32 (38%) and inducible ischemia in eight (12%). Corresponding results in aneurysmal ECAD were eight (30%) and two (11%), respectively (p for difference >.05). Sixteen (19%) patients with stenotic and six (22%) with aneurysmal ECAD were referred to a cardiologist, with subsequent cardiac intervention in seven (44%) and three (50%), respectively (both p >.05). CONCLUSIONS: Patients with stenotic or aneurysmal ECAD have a high prevalence of silent, significant CAD.

A prospective validation of the HEART score for chest pain patients at the emergency department.

BACKGROUND: The focus of the diagnostic process in chest pain patients at the emergency department is to identify both low and high risk patients for an acute coronary syndrome (ACS). The HEART score was designed to facilitate this process. This study is a prospective validation of the HEART score. METHODS: A total of 2440 unselected patients presented with chest pain at the cardiac emergency department of ten participating hospitals in The Netherlands. The HEART score was assessed as soon as the first lab results and ECG were obtained. Primary endpoint was the occurrence of major adverse cardiac events (MACE) within 6 weeks. Secondary endpoints were (i) the occurrence of AMI and death, (ii) ACS and (iii) the performance of a coronary angiogram. The performance of the HEART score was compared with the TIMI and GRACE scores. RESULTS: Low HEART scores (values 0-3) were calculated in 36.4% of the patients. MACE occurred in 1.7%. In patients with HEART scores 4-6, MACE was diagnosed in 16.6%. In patients with high HEART scores (values 7-10), MACE occurred in 50.1%. The c-statistic of the HEART score (0.83) is significantly higher than the c-statistic of TIMI (0.75)and GRACE (0.70) respectively (p<0.0001). CONCLUSION: The HEART score provides the clinician with a quick and reliable predictor of outcome, without computer-required calculating. Low HEART scores (0-3), exclude short-term MACE with >98% certainty. In these patients one might consider reserved policies. In patients with high HEART scores (7-10) the high risk of MACE may indicate more aggressive policies.

Myocardial perfusion reserve compared with peripheral perfusion reserve: a [13N]ammonia PET study.

INTRODUCTION: [13N]ammonia PET allows quantification of myocardial perfusion. The similarity between peripheral flow and myocardial perfusion is unclear. We compared perfusion flow in the myocardium with the upper limb during rest and adenosine stress [13N]ammonia PET to establish whether peripheral perfusion reserve (PPR) correlates with MPR. METHODS: [13N]ammonia myocardial perfusion PET-scans of 58 patients were evaluated (27 men, 31 women, age 64 ± 13 years) and were divided in four subgroups: patients with coronary artery disease (CAD, n = 15), cardiac syndrome X (SX, n = 14), idiopathic dilating cardiomyopathy (DCM, n = 16), and normal controls (NC, n = 13). Peripheral limb perfusion was measured in the muscular tissue of the proximal upper limb and quantified through a 2-tissue-compartment model and the PPR was calculated (stress/rest ratio). MPR was also calculated by a 2-tissue-compartment model. The PPR results were compared with the MPR findings. RESULTS: Mean myocardial perfusion increased significantly in all groups as evidenced by the MPR (CAD 1.99 ± 0.47; SX 1.39 ± 0.31; DCM 1.72 ± 0.69; NC 2.91 ± 0.78). Mean peripheral perfusion also increased but not significantly and accompanied with great variations within and between groups (mean PPR: CAD 1.30 ± 0.79; SX 1.36 ± 0.71; DCM 1.60 ± 1.22; NC 1.27 ± 0.63). The mean difference between PPR and MPR for all subpopulations varied widely. No significant correlations in flow reserve were found between peripheral and myocardial microcirculatory beds in any of the groups (Total group: r = -0.07, SEE = 0.70, CAD: r = 0.14, SEE = 0.48, SX: r = 0.17, SEE = 0.30, DCM: r = -0.11, SEE = 0.71, NC: r = -0.19, SEE = 0.80). CONCLUSION: No correlations between myocardial and peripheral perfusion (reserve) were found in different patient populations in the same PET session. This suggests a functional difference between peripheral and myocardial flow in the response to intravenously administered adenosine stress.

Myocardial perfusion reserve and contractile pattern after beta-blocker therapy in patients with idiopathic dilated cardiomyopathy.

BACKGROUND: In Idiopathic Dilated Cardiomyopathy (IDC) an imbalance between myocardial oxygen consumption and supply has been postulated. The ensuing subclinical myocardial ischemia may contribute to progressive deterioration of LV function. beta-blocker is the therapy of choice in these patients. However, not all patients respond to the same extent. The aim of this study was to elucidate whether differences between responders and non-responders can be identified with respect to regional myocardial perfusion reserve (MPR) and contractile performance. METHODS: Patients with newly diagnosed IDC underwent Positron Emission Tomography (PET) scanning using both (13)N-ammonia as a perfusion tracer (baseline and dipyridamole stress), and (18)F-fluoro-deoxyglucose as a metabolism tracer, and a dobutamine stress MRI. MRI and PET were repeated 6 months after maximal beta-blocker therapy. MPR (assessed by PET) as well as wall motion score (WMS, assessed by MRI) were evaluated in a 17 segment-model. Functional response to beta-blocker therapy was assigned as a stable or improved LVEF or diminished LVEF. RESULTS: Sixteen patients were included (age 47.9 +/- 11.5 years; 12 males, LVEF 28.6 +/- 8.4%). Seven patients showed improved LVEF (9.7 +/- 3.1%), and nine patients did not show improved LVEF (-3.4 +/- 3.9%). MPR improved significantly in responders (1.56 +/- .23 to 1.93 +/- .49, P = .049), and MPR decreased in non-responders; however, not significantly (1.98 +/- .70 to 1.61 +/- .28, P = .064), but was significantly different between both groups (P = .017) after beta-blocker therapy. A significant correlation was found between change in perfusion reserve and change in LVEF: a decrease in perfusion reserve was associated with a decrease in LVEF and vice versa. Summed rest score of wall motion in responders improved from 26 to 21 (P = .022) whereas in non-responders no change was observed from 26 to 25) (P = ns). Summed stress score of wall motion in responders improved from 23 to 21 (P = .027) whereas in non-responders no change was observed from 27 to 26) (P = ns). CONCLUSION: In IDC patients, global as well as regional improvement after initiation of beta-blocker treatment is accompanied by an improvement in regional perfusion parameters. On the other hand in IDC patients with further left ventricular function deterioration after initiation of beta-blocker therapy this is accompanied by a decrease in perfusion reserve.

Evaluation of global left ventricular function assessment of non-fluorescent electromechanical endocardial mapping compared with biplane left ventricular contrast angiography.

Background. Little is known about the diagnostic accuracy of global LV function assessment by electromechanical endocardial mapping (EEM). The aim of the present study was to determine the relationship between global left ventricular (LV) function measured by EEM and biplane left ventricular contrast angiography (LVA) after ST-elevation myocardial infarction (STEMI).Methods. Thirty-seven patients underwent LVA and EEM during routine coronary angiography four months after primary percutaneous intervention for STEMI. Global LV function parameters were available from both techniques in all patients. LVA was regarded as reference standard.Results. All procedures were carried out without adverse events. Average age was 55+/-10 years and 84% were male. EEM showed an overestimation of end-diastolic volume (EDV) and end-systolic volume (ESV) of 6.5 ml and 25.5 ml, respectively. Correlation (r) was 0.84 (p<0.001) for EDV and 0.74 (p<0.001) for ESV. Average left ventricular ejection fraction (LVEF) measured by EEM was 17.2% point (+/-11.3% point) lower compared with LVA (r=0.69, p<0.001).Conclusion. Although global functional parameters by EEM correlated well with LVA, the relatively large differences in terms of absolute values for ventricular volumes and LVEF render the two techniques non-interchangeable for global LV-function-data. (Neth Heart J 2010;18:72-77.).

Matrix metalloproteinases 2 and 3 gene polymorphisms and the risk of target vessel revascularization after percutaneous coronary intervention: Is there still room for determining genetic variation of MMPs for assessment of an increased risk of restenosis?

OBJECTIVE: Mixed results have been reported of matrix metalloproteinases (MMP) and their association with restenosis after percutaneous coronary intervention (PCI). The current study examines whether multiple single nucleotide polymorphisms (SNPs), covering the full genomic region of MMP2 and MMP3, were associated with restenosis in the GENDER study population. METHODS AND RESULTS: The GENetic DEterminants of Restenosis (GENDER) study enrolled 3104 consecutive patients after successful PCI. The primary endpoint was clinical restenosis, defined as target vessel revascularization (TVR), occurring in 9.8% of the patients. From the Hapmap database, 19 polymorphisms of MMP2 and 11 of MMP3 were selected. Furthermore, in a subpopulation, a genome-wide association analysis (GWA) was performed. No significant association was found with any of the investigated SNPs, including the previously reported 5A/6A polymorphism (rs3025058), with regard to TVR using single SNP analysis or haplotype analysis. CONCLUSION: We found no significant association of MMP2 or MMP3 with TVR with this SNP-broad gene approach. Although we did not test all the known polymorphisms of these genes, using tagging analyses we examined those SNPs covering all known haplotypes of MMP2 and MMP3 to conclude that these genes do not correlate with a genetic risk of coronary restenosis after successful PCI.

The diagnostic value of soluble CD163 in patients presenting with chest pain.

BACKGROUND: CD163 is a scavenger receptor for the uptake of haptoglobin-hemoglobin (Hpt-Hb) complexes. The Hpt-Hb complexes are being formed in the plaque in response to intraplaque hemorrhage, a hallmark of atherosclerotic plaque instability. We therefore investigated whether soluble CD163 (sCD163) was elevated in patients with an acute coronary syndrome. METHODS: All subjects presenting with chest pain suggestive of myocardial ischemia referred to either the emergency department or the coronary care unit were included in a prospective follow-up study. Plasma was collected and frozen at -80 degrees C until assayed. sCD163 was measured using a commercially available Elisa assay. RESULTS: Of 526 included chest pain patients, the final diagnosis was non-cardiac chest pain in 244 (46%) patients, non-STEMI in 67 (13%), and STEMI in 215 (41%). The non-STEMI patients were older, used more medication, had undergone more often coronary interventions, but did not differ with respect to risk factors, except for a higher incidence in dyslipidemia. Unexpectedly, sCD163 did not differentiate between patients with non-STEMI or STEMI and the non-cardiac chest pain patients (2.09+/-0.76 versus 2.24+/-0.86). CONCLUSION: Although ACS is characterized by intraplaque hemorrhage, the amount of intraplaque Hb release seems not to be substantial enough to result in a measurable difference in sCD163.

Nuclear imaging in cardiac amyloidosis.

Amyloidosis is a disease characterized by depositions of amyloid in organs and tissues. It can be localized (in just one organ) or systemic. Cardiac amyloidosis is a debilitating disease and can lead to arrhythmias, deterioration of heart function and even sudden death. We reviewed PubMed/Medline, without time constraints, on the different nuclear imaging modalities that are used to visualize myocardial amyloid involvement. Several SPECT tracers have been used for this purpose. The results with these tracers in the evaluation of myocardial amyloidosis and their mechanisms of action are described. Most clinical evidence was found for the use of (123)I-MIBG. Myocardial defects in MIBG activity seem to correlate well with impaired cardiac sympathetic nerve endings due to amyloid deposits. (123)I-MIBG is an attractive option for objective evaluation of cardiac sympathetic level and may play an important role in the indirect measurement of the effect of amyloid myocardial infiltration. Other, less sensitive, options are (99m)Tc-aprotinin for imaging amyloid deposits and perhaps (99m)Tc-labelled phosphate derivatives, especially in the differential diagnosis of the aetiology of cardiac amyloidosis. PET tracers, despite the advantage of absolute quantification and higher resolution, are not yet well evaluated for the study of cardiac amyloidosis. Because of these advantages, there is still the need for further research in this field.

Reduced regional myocardial perfusion reserve is associated with impaired contractile performance in idiopathic dilated cardiomyopathy.

Background. In idiopathic dilated cardiomyopathy (IDC) an imbalance between myocardial oxygen consumption and supply has been postulated. Subclinical myocardial ischaemia may contribute to progressive deterioration of left ventricular function. The relation between regional myocardial perfusion reserve (MPR) and contractile performance was investigated.Methods. Patients with newly diagnosed IDC underwent positron emission tomography (PET) scanning using both (13)N-ammonia as a perfusion tracer (baseline and dypiridamole stress), and (18)F-fluorodeoxyglucose viability tracer and a dobutamine stress MRI. MPR (assessed by PET) as well as wall motion score (WMS, assessed by MRI) were evaluated in a 17-segment model.Results. Twenty-two patients were included (age 49+/-11 years; 15 males, LVEF 33+/-10%). With MRI, a total of 305 segments could be analysed. Wall motion abnormalities at rest were present in 127 (35.5%) segments and in 103 (29.9%) during dobutamine stress. Twenty-one segments deteriorated during stress and 43 improved. MPR was significantly higher in those segments that improved, compared with those that did not change or were impaired during stress (1.87+/-0.04 vs. 1.56+/- 0.07 p<0.01.)Conclusion. Signs of regional ischaemia were clearly present in IDC patients. Ischaemic regions displayed impaired contractility during stress. This suggests that impaired oxygen supply contributes to cardiac dysfunction in IDC. (Neth Heart J 2009;17:470-4.).

Restenosis begets restenosis: implications for stent selection.

BACKGROUND: Identifying the risk for restenosis is of critical importance in the stent selection process of patients undergoing percutaneous coronary intervention (PCI). Therefore, we sought to determine if a history of clinical recurrence (CR) after PCI increases the risk of CR after treatment of a de novo lesion in another coronary artery. METHODS: We retrospectively analysed all 12,763 patients who underwent PCI between 1993 and 2004 and selected patients with two or more interventions in two different native vessels. These patients were divided into two groups: patients without CR, and patients with CR after the first PCI. Clinical recurrence was defined as revascular-isation of the target vessel by either PCI or CABG within one year. RESULTS: A total of 1010 patients with two or more interventions in two different native vessels were identified: 727 patients without and 283 patients with CR after the first PCI. Baseline patient characteristics and conventional risk factors were comparable between the two groups. Patients with a history of CR had a higher risk of CR after a second intervention in a second vessel (OR=3.4, 95% CI=2.3 to 4.9). A total of 112 patients also had a third intervention in a third native vessel: 12 patients with two CR, 30 patients with one CR and 70 patients with no CR after the first two interventions. CR rates in these patients were 50, 17 and 3%, respectively (p<0.001). CONCLUSION: Patients with a history of CR have a markedly increased risk of developing CR after a second or third PCI in a different coronary artery. Therefore, in the decision-making process on whether to use a bare metal stent or drug-eluting stent, the history of CR is a simple and powerful aid. (Neth Heart J 2008;16:376-81.).

Visualization of anomalous coronary arteries on dual-source computed tomography.

The purpose of this study is to assess the capability of dual-source computed tomography (DSCT) in evaluating coronary artery anomalies. Early detection and evaluation of coronary artery anomalies is essential because of their potential association with myocardial ischemia and sudden death. In 16 patients (12 men, mean age 50 +/- 14 years), anomalous coronary arteries were detected on contrast-enhanced DSCT in a patient cohort of 230 individuals (incidence of 7%). Six different types of anomalies were diagnosed (three fistula, four anomalies of the circumflex artery, four anomalous right coronary arteries, three anomalies of the left coronary artery, one absent left main coronary artery, and one left coronary artery arising from the pulmonary trunk). Of the 16 patients, 10 also underwent conventional coronary angiography (CAG). Retrospective evaluation of the CAGs by an experienced interventional cardiologist resulted in a precise diagnosis in 50% of patients. With DSCT, sufficient image quality and exact visualization of the aberrant anatomy were achieved in all patients. Therefore, DSCT seems to be an accurate diagnostic tool for examining the precise origin, course, and shape of aberrant coronary arteries.

Coronary revascularization treatment based on dual-source computed tomography.

Therapy advice based on dual-source computed tomography (DSCT) in comparison with coronary angiography (CAG) was investigated and the results evaluated after 1-year follow-up. Thirty-three consecutive patients (mean age 61.9 years) underwent DSCT and CAG and were evaluated independently. In an expert reading (the "gold standard"), CAG and DSCT examinations were evaluated simultaneously by an experienced radiologist and cardiologist. Based on the presence of significant stenosis and current guidelines, therapy advice was given by all readers blinded from the results of other readings and clinical information. Patients were treated based on a multidisciplinary team evaluation including all clinical information. In comparison with the gold standard, CAG had a higher specificity (91%) and positive predictive value (PPV) (95%) compared with DSCT (82% and 91%, respectively). DSCT had a higher sensitivity (96%) and negative predictive value (NPV) (89%) compared with CAG (91% and 83%, respectively). The DSCT-based therapy advice did not lead to any patient being denied the revascularization they needed according to the multidisciplinary team evaluation. During follow-up, two patients needed additional revascularization. The high NPV for DSCT for revascularization assessment indicates that DSCT could be safely used to select patients benefiting from medical therapy only.