Dr Nieman is a cardiologist and associate professor in the departments of cardiovascular medicine and radiology. He came to Stanford in September 2016. He investigates advanced cardiac imaging techniques, and current projects include the development and technical validation of functional CT applications for ischemic heart disease, and the clinical validation of cardiac CT in the form of clinical effectiveness trials.
Dr Nieman was born in the Netherlands, obtained his medical degree at the Radboud University in Nijmegen (1998), and completed his cardiology training at the Erasmus University Medical Center in Rotterdam (2008). His research in cardiac CT at the Erasmus University resulted in a PhD degree in 2003. In 2004 he performed an imaging fellowship at the Massachusetts General Hospital (Harvard Medical School) in Boston, MA. Dr Nieman joined the staff of the department of cardiology and radiology at the Erasmus University Medical Center in 2008, where he was scientific director of the cardiac CT and MRI group and supervised the intensive cardiac care unit until he joined the staff at Stanford University.

Clinical Focus

  • Cardiology

Academic Appointments

Boards, Advisory Committees, Professional Organizations

  • Board member, Society of Cardiovascular CT (2015 - Present)
  • ASM program committee, Society of Cardiovascular CT (2014 - Present)
  • Board member, Netherlands Vascular Forum (2013 - 2016)
  • Nucleus member CT/Nuc section, European Association of Cardiovascular Imaging (2012 - Present)
  • Research and innovation committee, European Association of Cardiovascular Imaging (2012 - Present)
  • Chair - CT/MR/Nuc working group, Dutch Cardiology Association (2012 - 2015)
  • Secretary - CT/MR/Nuc working group, Dutch Cardiology Association (2009 - 2012)

Professional Education

  • Board Certification: Cardiology, RGS KNMG Dept of Postgraduate Training (2008)
  • PhD Training:Erasmus University Medical Center (2003) Netherlands
  • Fellowship:Massachusetts General Hospital Dept of Radiology (2005) MAUnited States of America
  • Residency:Erasmus University Medical Center (2008) Netherlands
  • Internship:Radboud University (1998) Netherlands
  • Medical Education:Radboud University (1998) Netherlands
  • Cardiologist, Erasmus University, Rotterdam, NL, Cardiology (2008)
  • PhD, Erasmus University, Rotterdam, NL, Cardiac CT (2003)
  • MD, Radboud University, Nijmegen, NL, Medicine (1998)

Research & Scholarship

Current Research and Scholarly Interests

Current research interests:

Functional cardiac CT applications for the hemodynamic interpretation of coronary artery disease:
- CT myocardial perfusion imaging (SPECIFIC trial).
- CTA derived fractional flow reserve.

Clinical validation of cardiac CT in cardiovascular medicine:
- Coronary CT angiography for the triage of patients with acute chest pain (BEACON randomized controlled trial).
- Tiered cardiac CT protocols algorithms for comprehensive assessment of patients with stable anginal complaints (CRESCENT randomized controlled trials)

Comprehensive evaluation of patients with symptoms after coronary revascularization.

Noninvasive charaterization of atherosclerotic plaque.

4D MR flow imaging in structural heart disease.

Cardiac CT in structural heart disease.

Contrast media (CT-CON and IsoCOR randomized controlled trials).


  • SPECIFIC Trial, Stanford University and others (5/1/2016)

    International, multicenter trial to validate the diagnostic value of dynamic CT myocardial perfusion imaging to identify hemodynamically relevant coronary artery disease, using measured fractional flow reserve as reference.





All Publications

  • Highlights of the thirteenth annual scientific meeting of the Society of Cardiovascular Computed Tomography. Journal of cardiovascular computed tomography Weir-McCall, J. R., Madan, N., Villines, T. C., Shaw, L. J., Abbara, S., Ferencik, M., Nieman, K., Blankstein, R., Ghoshhajra, B. B., Choi, A. D., Nicol, E. 2018


    The 13th Annual Scientific Meeting of the SCCT, held from July 13 to July 15 in Dallas, TX, was attended by 690 attendees from 39 countries, 55 sessions with 140 speakers, and 18 exhibitors with the abstracts of all scientific posters published in the Journal of the Cardiovascular Computed Tomography. This article summarizes the many themes and topics of presentation and discussion in this meeting, and the many technical advances that are likely to impact future clinical practice in cardiac computed tomography and feature in future meetings.

    View details for DOI 10.1016/j.jcct.2018.09.005

    View details for PubMedID 30292790

  • Computed tomography myocardial perfusion imaging vs. computed tomography-derived fractional flow reserve, which way forward? European heart journal cardiovascular Imaging Nieman, K. 2018

    View details for DOI 10.1093/ehjci/jey125

    View details for PubMedID 30239647

  • Diagnostic Accuracy of a Machine-Learning Approach to Coronary Computed Tomographic Angiography-Based Fractional Flow Reserve Result From the MACHINE Consortium CIRCULATION-CARDIOVASCULAR IMAGING Coenen, A., Kim, Y., Kruk, M., Tesche, C., De Geer, J., Kurata, A., Lubbers, M. L., Daemen, J., Itu, L., Rapaka, S., Sharma, P., Schwemmer, C., Persson, A., Schoepf, U., Kepka, C., Yang, D., Nieman, K. 2018; 11 (6): e007217


    Coronary computed tomographic angiography (CTA) is a reliable modality to detect coronary artery disease. However, CTA generally overestimates stenosis severity compared with invasive angiography, and angiographic stenosis does not necessarily imply hemodynamic relevance when fractional flow reserve (FFR) is used as reference. CTA-based FFR (CT-FFR), using computational fluid dynamics (CFD), improves the correlation with invasive FFR results but is computationally demanding. More recently, a new machine-learning (ML) CT-FFR algorithm has been developed based on a deep learning model, which can be performed on a regular workstation. In this large multicenter cohort, the diagnostic performance ML-based CT-FFR was compared with CTA and CFD-based CT-FFR for detection of functionally obstructive coronary artery disease.At 5 centers in Europe, Asia, and the United States, 351 patients, including 525 vessels with invasive FFR comparison, were included. ML-based and CFD-based CT-FFR were performed on the CTA data, and diagnostic performance was evaluated using invasive FFR as reference. Correlation between ML-based and CFD-based CT-FFR was excellent (R=0.997). ML-based (area under curve, 0.84) and CFD-based CT-FFR (0.84) outperformed visual CTA (0.69; P<0.0001). On a per-vessel basis, diagnostic accuracy improved from 58% (95% confidence interval, 54%-63%) by CTA to 78% (75%-82%) by ML-based CT-FFR. The per-patient accuracy improved from 71% (66%-76%) by CTA to 85% (81%-89%) by adding ML-based CT-FFR as 62 of 85 (73%) false-positive CTA results could be correctly reclassified by adding ML-based CT-FFR.On-site CT-FFR based on ML improves the performance of CTA by correctly reclassifying hemodynamically nonsignificant stenosis and performs equally well as CFD-based CT-FFR.

    View details for DOI 10.1161/CIRCIMAGING.117.007217

    View details for Web of Science ID 000435564000003

    View details for PubMedID 29914866

  • Round-the-clock performance of coronary CT angiography for suspected acute coronary syndrome: Results from the BEACON trial EUROPEAN RADIOLOGY Lubbers, M. M., Dedic, A., Kurata, A., Dijkshoorn, M., Schaap, J., Lammers, J., Lamfers, E. J., Rensing, B. J., Braam, R. L., Nathoe, H. M., Post, J. C., Rood, P. P., Schultz, C. J., Moelker, A., Ouhlous, M., van Dalen, B. M., Boersma, E., Nieman, K. 2018; 28 (5): 2169–75


    To assess the image quality of coronary CT angiography (CCTA) for suspected acute coronary syndrome (ACS) outside office hours.Patients with symptoms suggestive of an ACS underwent CCTA at the emergency department 24 hours, 7 days a week. A total of 118 patients, of whom 89 (75 %) presented during office hours (weekdays between 07:00 and 17:00) and 29 (25 %) outside office hours (weekdays between 17:00 and 07:00, weekends and holidays) underwent CCTA. Image quality was evaluated per coronary segment by two experienced readers and graded on an ordinal scale ranging from 1 to 3.There were no significant differences in acquisition parameters, beta-blocker administration or heart rate between patients presenting during office hours and outside office hours. The median quality score per patient was 30.5 [interquartile range 26.0-33.5] for patients presenting during office hours in comparison to 27.5 [19.75-32.0] for patients presenting outside office hours (p=0.043). The number of non-evaluable segments was lower for patients presenting during office hours (0 [0-1.0] vs. 1.0 [0-4.0], p=0.009).Image quality of CCTA outside office hours in the diagnosis of suspected ACS is diminished.• Quality scores were higher for coronary-CTA during office hours. • There were no differences in acquisition parameters. • There was a non-significant trend towards higher heart rates outside office hours. • Coronary-CTA on the ED requires state-of-the-art scanner technology and sufficiently trained staff. • Coronary-CTA on the ED needs preparation time and optimisation of the procedure.

    View details for DOI 10.1007/s00330-017-5082-7

    View details for Web of Science ID 000429104200042

    View details for PubMedID 29247351

    View details for PubMedCentralID PMC5882623

  • Strategies for radiation dose reduction in nuclear cardiology and cardiac computed tomography imaging: a report from the European Association of Cardiovascular Imaging (EACVI), the Cardiovascular Committee of European Association of Nuclear Medicine (EANM), and the European Society of Cardiovascular Radiology (ESCR) EUROPEAN HEART JOURNAL Gimelli, A., Achenbach, S., Buechel, R. R., Edvardsen, T., Francone, M., Gaemperli, O., Hacker, M., Hyafil, F., Kaufmann, P. A., Lancellotti, P., Nieman, K., Pontone, G., Pugliese, F., Verberne, H. J., Gutberlet, M., Bax, J. J., Neglia, D. 2018; 39 (4): 286–94

    View details for DOI 10.1093/eurheartj/ehx582

    View details for Web of Science ID 000423309200009

    View details for PubMedID 29059384

  • Iodixanol versus lopromide at Coronary CT Angiography: Lumen Opacification and Effect on Heart Rhythm-the Randomized IsoCOR Trial RADIOLOGY Lubbers, M. M., Kock, M., Niezen, A., Galema, T., Kofflard, M., Bruning, T., Kooij, H. S., van Valen, H., Dijkshoorn, M., Booij, R., Padmos, A., Vogels, A., Budde, R. J., Nieman, K. 2018; 286 (1): 71–80


    Purpose To show that equal coronary lumen opacification can be achieved with iso- and low-osmolar contrast media when it is injected at the same iodine delivery rate with contemporary cardiac computed tomographic (CT) protocols and to investigate the cardiovascular effect of iso-osmolar contrast media and the image quality achieved. Materials and Methods Institutional review board approval and written informed consent were obtained for the Effect of Iso-osmolar Contrast Medium on Coronary Opacification and Heart Rhythm in Coronary CT Angiography, or IsoCOR, trial. Between November 2015 and August 2016, 306 patients (167 [55%] women) at least 18 years old (weight range, 50-125 kg), were prospectively randomized to receive iso-osmolar iodixanol 270 or low-osmolar iopromide 300 contrast media. All coronary segments were assessed for intraluminal opacification and image quality and were compared by using the Student t test. Heart rate, arrhythmia, patient discomfort, and adverse events also were monitored. Results Mean measured coronary attenuation values ± standard deviation were comparable between the iodixanol 270 and iopromide 300 contrast media groups (469 HU ± 167 vs 447 HU ± 166, respectively [P = .241]; 95% confidence interval: -15.1, 60.0), including those from subanalyses. Adjusted for the lower iodine concentration, the mean iodixanol 270 bolus was larger compared with that of iopromide 300 (76.8 mL ± 11.6 vs 69.7 mL ± 10.8, respectively; P < .001). The higher injection rate was associated with higher pressure (777 kPa ± 308 vs 630 kPa ± 252, respectively; P < .001). Although in the iodixanol 270 group patients experienced less heat discomfort (72% vs 86%, respectively; P < .001), no differences in heart rate or rhythm were observed. Conclusion If injected at comparable iodine delivery rates, the iso-osmolar contrast medium iodixanol 270 is not inferior to low-osmolar contrast medium iopromide 300 for assessment of coronary opacification. Iodixanol 270 was associated with less heat discomfort, but did not affect heart rate differently compared with iopromide 300. © RSNA, 2017 Online supplemental material is available for this article.

    View details for DOI 10.1148/radiol.2017162779

    View details for Web of Science ID 000422905200011

    View details for PubMedID 28809582

  • Highlights of the Twelfth Annual Scientific Meeting of the Society of Cardiovascular Computed Tomography JOURNAL OF CARDIOVASCULAR COMPUTED TOMOGRAPHY Weir-McCall, J. R., Villines, T. C., Shaw, L. J., Abbara, S., Ferencik, M., Nieman, K., Achenbach, S., Nicol, E. 2018; 12 (1): 3–7


    The 12th Annual Scientific Meeting of the SCCT, held from July 6 to July 9 in Washington, DC, was one of the largest to date with 724 attendants from 34 countries, 130 invited talks, 4 "Read with the Experts" sessions, 42 oral abstracts presented, 20 rapid fire posters and 164 poster presentations with the abstracts of all of these published in the JCCT. This article summarises the many themes and topics of presentation and discussion in this meeting, and the many technical advances that are likely to impact future clinical practice and feature in future meetings.

    View details for DOI 10.1016/j.jcct.2017.11.001

    View details for Web of Science ID 000424290500003

    View details for PubMedID 29174217

  • Coronary artery calcium: A technical argument for a new scoring method. Journal of cardiovascular computed tomography Willemink, M. J., van der Werf, N. R., Nieman, K., Greuter, M. J., Koweek, L. M., Fleischmann, D. 2018


    Coronary artery calcium (CAC) is a strong predictor for future cardiovascular events. Traditionally CAC has been quantified using the Agatston score, which was developed in the late 1980s for electron beam tomography (EBT). While EBT has been completely replaced by modern multiple-detector row CT technology, the traditional CAC scoring method by Agatston remains in use, although the literature indicates suboptimal reproducibility and subjects being incorrectly classified. The traditional Agatston scoring method counteracts the technical advances of CT technology, and prevents the use of thinner sections, obtained at lower tube voltage and overall decreased radiation exposure that has become available to other CT applications. Moreover, recent studies have shown that not only the total amount of CAC, but also its density and distribution in the coronary arterial tree may be of prognostic value. Acquisition and reconstruction techniques thus need to be adapted for modern CT technology and optimized for CAC quantification. In this review we describe the technical limitations of the Agatston score followed by our suggestions for developing a new and more robust CAC quantification method.

    View details for DOI 10.1016/j.jcct.2018.10.014

    View details for PubMedID 30366859

  • Diagnostic Value of Transluminal Attenuation Gradient for the Presence of Ischemia as Defined by Fractional Flow Reserve and Quantitative Positron Emission Tomography. JACC. Cardiovascular imaging Bom, M. J., Driessen, R. S., Stuijfzand, W. J., Raijmakers, P. G., Van Kuijk, C. C., Lammertsma, A. A., van Rossum, A. C., van Royen, N., Knuuti, J., Maki, M., Nieman, K., Min, J. K., Leipsic, J. A., Danad, I., Knaapen, P. 2017


    OBJECTIVES: The aim of this study was to investigate the incremental diagnostic value of transluminal attenuation gradient (TAG), TAG with corrected contrast opacification (TAG-CCO), and transluminal diameter gradient (TDG) over coronary computed tomography angiography (CTA)-derived diameter stenosis alone for the identification of ischemia as defined by both the invasive reference standard fractional flow reserve (FFR) and the noninvasive reference standard quantitative positron emission tomography (PET).BACKGROUND: In addition to anatomic information obtained by coronary CTA, several functional CT parameters have been proposed to identify hemodynamically significant lesions more accurately, such as TAG, TAG-CCO, and more recently TDG. However, clinical validation studies have reported conflicting results, and a recent study has suggested that TAG may be affected by changes in vessel diameter.METHODS: Patients with suspected coronary artery disease underwent coronary CTA and [15O]H2O PET followed by invasive coronary angiography with FFR of all major coronary arteries. TAG, TAG-CCO, and TDG were assessed, and the incremental diagnostic value of these parameters over coronary CTA-derived diameter stenosis alone for ischemia as defined by PET (hyperemic myocardial blood flow≤2.30 ml/min/g) and FFR (≤0.80) was determined.RESULTS: A total of 557 (91.9%) coronary arteries of 201 patients were included for analysis. TAG, TAG-CCO, and TDG did not discriminate between vessels with or without ischemia as defined by either PET or FFR. Furthermore, these parameters did not have incremental diagnostic accuracy over coronary CTA alone for the presence of ischemia as defined by PET and FFR. There was a significant correlation between TDG and TAG (r= 0.47; p< 0.001) and between TDG and TAG-CCO (r= 0.37; p< 0.001).CONCLUSIONS: TAG, TAG-CCO, and TDG do not provide incremental diagnostic value over coronary CTA alone for the presence of ischemia as defined by [15O]H2O PET and/or FFR. The lack of diagnostic value of contrast enhancement-based flow estimations appears related to coronary luminal dimension variability.

    View details for DOI 10.1016/j.jcmg.2017.10.009

    View details for PubMedID 29248645

  • Is there still a role for cardiac CT in the emergency department in the era of highly-sensitive troponins? Minerva cardioangiologica Dedic, A., Nieman, K., Hoffmann, U., Ferencik, M. 2017; 65 (3): 214-224


    Physicians practicing cardiovascular medicine are every day confronted with patients presenting with symptoms suggestive of an acute coronary syndrome (ACS). Over the years, there have been substantial technical advances, such as the introduction of new non-invasive imaging techniques and the introduction of new highly sensitive cardiac biomarkers. Physicians have adopted these new assets and have become more experienced with them thus improving medical care. Nevertheless, the search for an efficient, yet safe diagnostic work-up for patients presenting with symptoms suggestive of ACS is ongoing. A large proportion of patients will require some form of non-invasive testing and the choice for the diagnostic modality as well as its timing are important steps in this process. Cardiac computed tomography (CT), a non-invasive imaging technique that rapidly provides visualization of the coronary artery tree, is an attractive option, with its unparalleled negative predictive value for obstructive coronary artery disease (CAD). With the introduction of highly-sensitive troponins (hsTn), the role of non-invasive testing, including cardiac CT, has changed. This review will provide an oversight on what is known about cardiac CT in acute chest presentations. Furthermore, we will discuss the changing role of cardiac CT in the era of hsTn and the possibility of their combined use in the work-up of suspected ACS patients. hsTn is currently an established tool for the diagnosis and triage of patients with suspected ACS. The role of cardiac CT has shifted now to a secondary, comprehensive rule-out test in patients with inconclusive biomarker status, providing information on stenosis severity, plaque burden, high-risk features and the presence of other serious conditions that can also give rise to hsTn.

    View details for DOI 10.23736/S0026-4725.16.04291-2

    View details for PubMedID 27886161

  • Sex Differences in the Performance of Cardiac Computed Tomography Compared With Functional Testing in Evaluating Stable Chest Pain: Subanalysis of the Multicenter, Randomized CRESCENT Trial (Calcium Imaging and Selective CT Angiography in Comparison to Functional Testing for Suspected Coronary Artery Disease). Circulation. Cardiovascular imaging Lubbers, M., Coenen, A., Bruning, T., Galema, T., Akkerhuis, J., Krenning, B., Musters, P., Ouhlous, M., Liem, A., Niezen, A., Dedic, A., van Domburg, R., Hunink, M., Nieman, K. 2017; 10 (2)


    Cardiac computed tomography (CT) represents an alternative diagnostic strategy for women with suspected coronary artery disease, with potential benefits in terms of effectiveness and cost-efficiency.The CRESCENT trial (Calcium Imaging and Selective CT Angiography in Comparison to Functional Testing for Suspected Coronary Artery Disease) prospectively randomized 350 patients with stable angina (55% women; aged 55±10 years), mostly with an intermediate coronary artery disease probability, between cardiac CT and functional testing. The tiered cardiac CT protocol included a calcium scan followed by CT angiography if the Agatston calcium score was between 1 and 400. Patients with test-specific contraindications were not excluded from study participation. Sex differences were studied as a prespecified subanalysis. Enrolled women presented more frequently with atypical chest pain and had a lower pretest probability of coronary artery disease compared with men. Independently of these differences, cardiac CT led in both sexes to a fast final diagnosis when compared with functional testing, although the effect was larger in women (P interaction=0.01). The reduced need for further testing after CT, compared with functional testing, was most evident in women (P interaction=0.009). However, no sex interaction was observed with respect to changes in angina and quality of life, cumulative diagnostic costs, and applied radiation dose (all P interactions≥0.097).Cardiac CT is more efficient in women than in men in terms of time to reach the final diagnosis and downstream testing. However, overall clinical outcome showed no significant difference between women and men after 1 year.URL: Unique identifier: NCT01393028.

    View details for DOI 10.1161/CIRCIMAGING.116.005295

    View details for PubMedID 28174196

  • Cloud-processed 4D CMR flow imaging for pulmonary flow quantification. European journal of radiology Chelu, R. G., Wanambiro, K. W., Hsiao, A., Swart, L. E., Voogd, T., van den Hoven, A. T., van Kranenburg, M., Coenen, A., Boccalini, S., Wielopolski, P. A., Vogel, M. W., Krestin, G. P., Vasanawala, S. S., Budde, R. P., Roos-Hesselink, J. W., Nieman, K. 2016; 85 (10): 1849-1856


    In this study, we evaluated a cloud-based platform for cardiac magnetic resonance (CMR) four-dimensional (4D) flow imaging, with fully integrated correction for eddy currents, Maxwell phase effects, and gradient field non-linearity, to quantify forward flow, regurgitation, and peak systolic velocity over the pulmonary artery.We prospectively recruited 52 adult patients during one-year period from July 2014. The 4D flow and planar (2D) phase-contrast (PC) were acquired during same scanning session, but 4D flow was scanned after injection of a gadolinium-based contrast agent. Eddy-currents were semi-automatically corrected using the web-based software. Flow over pulmonary valve was measured and the 4D flow values were compared against the 2D PC ones.The mean forward flow was 92 (±30) ml/cycle measured with 4D flow and 86 (±29) ml/cycle measured with 2D PC, with a correlation of 0.82 and a mean difference of -6ml/cycle (-41-29). For the regurgitant fraction the correlation was 0.85 with a mean difference of -0.95% (-17-15). Mean peak systolic velocity measured with 4D flow was 92 (±49) cm/s and 108 (±56) cm/s with 2D PC, having a correlation of 0.93 and a mean difference of 16cm/s (-24-55).4D flow imaging post-processed with an integrated cloud-based application accurately quantifies pulmonary flow. However, it may underestimate the peak systolic velocity.

    View details for DOI 10.1016/j.ejrad.2016.07.018

    View details for PubMedID 27666627

  • Calcium imaging and selective computed tomography angiography in comparison to functional testing for suspected coronary artery disease: the multicentre, randomized CRESCENT trial EUROPEAN HEART JOURNAL Lubbers, M., Dedic, A., Coenen, A., Galema, T., Akkerhuis, J., Bruning, T., Krenning, B., Musters, P., Ouhlous, M., Liem, A., Niezen, A., Hunink, M., de Feijter, P., Nieman, K. 2016; 37 (15): 1232-1243


    To compare the effectiveness and safety of a cardiac computed tomography (CT) algorithm with functional testing in patients with symptoms suggestive of coronary artery disease (CAD).Between April 2011 and July 2013, 350 patients with stable angina, referred to the outpatient clinic of four Dutch hospitals, were prospectively randomized between cardiac CT and functional testing (2 : 1 ratio). The tiered cardiac CT protocol included a calcium scan followed by CT angiography if the Agatston calcium score was between 1 and 400. Patients with test-specific contraindications were not excluded from study participation. By 1 year, fewer patients randomized to cardiac CT reported anginal complaints (P = 0.012). The cumulative radiation dose was slightly higher in the CT group (6.6 ± 8.7 vs. 6.1 ± 9.3 mSv; P < 0.0001). After 1.2 years, event-free survival was 96.7% for patients randomized to CT and 89.8% for patients randomized to functional testing (P = 0.011). After CT, the final diagnosis was established sooner (P < 0.0001), and additional downstream testing was required less frequently (25 vs. 53%, P < 0.0001), resulting in lower cumulative diagnostic costs (€369 vs. €440; P < 0.0001).For patients with suspected stable CAD, a tiered cardiac CT protocol offers an effective and safe alternative to functional testing. Incorporating the calcium scan into the diagnostic workup was safe and lowered diagnostic expenses and radiation exposure.

    View details for DOI 10.1093/eurheartj/ehv700

    View details for Web of Science ID 000373985800015

    View details for PubMedID 26746631

  • 'Prognostic implications of non-culprit plaques in acute coronary syndrome: non-invasive assessment with coronary CT angiography'. European heart journal cardiovascular Imaging Dedic, A., Kurata, A., Lubbers, M., Meijboom, W. B., van Dalen, B. M., Snelder, S., Korbee, R., Moelker, A., Ouhlous, M., Van Domburg, R., de Feijter, P. J., Nieman, K. 2016; 17 (4): 392-?

    View details for DOI 10.1093/ehjci/jew002

    View details for PubMedID 26912666

  • Qualitative grading of aortic regurgitation: a pilot study comparing CMR 4D flow and echocardiography INTERNATIONAL JOURNAL OF CARDIOVASCULAR IMAGING Chelu, R. G., van den Bosch, A. E., van Kranenburg, M., Hsiao, A., van den Hoven, A. T., Ouhlous, M., Budde, R. P., Beniest, K. M., Swart, L. E., Coenen, A., Lubbers, M. M., Wielopolski, P. A., Vasanawala, S. S., Roos-Hesselink, J. W., Nieman, K. 2016; 32 (2): 301-307
  • Coronary CT Angiography for Suspected ACS in the Era of High-Sensitivity Troponins: Randomized Multicenter Study. Journal of the American College of Cardiology Dedic, A., Lubbers, M. M., Schaap, J., Lammers, J., Lamfers, E. J., Rensing, B. J., Braam, R. L., Nathoe, H. M., Post, J. C., Nielen, T., Beelen, D., le Cocq d'Armandville, M., Rood, P. P., Schultz, C. J., Moelker, A., Ouhlous, M., Boersma, E., Nieman, K. 2016; 67 (1): 16-26


    It is uncertain whether a diagnostic strategy supplemented by early coronary computed tomography angiography (CCTA) is superior to contemporary standard optimal care (SOC) encompassing high-sensitivity troponin assays (hs-troponins) for patients suspected of acute coronary syndrome (ACS) in the emergency department (ED).This study assessed whether a diagnostic strategy supplemented by early CCTA improves clinical effectiveness compared with contemporary SOC.In a prospective, open-label, multicenter, randomized trial, we enrolled patients presenting with symptoms suggestive of an ACS at the ED of 5 community and 2 university hospitals in the Netherlands. Exclusion criteria included the need for urgent cardiac catheterization and history of ACS or coronary revascularization. The primary endpoint was the number of patients identified with significant coronary artery disease requiring revascularization within 30 days.The study population consisted of 500 patients, of whom 236 (47%) were women (mean age 54 ± 10 years). There was no difference in the primary endpoint (22 [9%] patients underwent coronary revascularization within 30 days in the CCTA group and 17 [7%] in the SOC group [p = 0.40]). Discharge from the ED was not more frequent after CCTA (65% vs. 59%, p = 0.16), and length of stay was similar (6.3 h in both groups; p = 0.80). The CCTA group had lower direct medical costs (€337 vs. €511, p < 0.01) and less outpatient testing after the index ED visit (10 [4%] vs. 26 [10%], p < 0.01). There was no difference in incidence of undetected ACS.CCTA, applied early in the work-up of suspected ACS, is safe and associated with less outpatient testing and lower costs. However, in the era of hs-troponins, CCTA does not identify more patients with significant CAD requiring coronary revascularization, shorten hospital stay, or allow for more direct discharge from the ED. (Better Evaluation of Acute Chest Pain with Computed Tomography Angiography [BEACON]; NCT01413282).

    View details for DOI 10.1016/j.jacc.2015.10.045

    View details for PubMedID 26764061

  • Diagnostic value of transmural perfusion ratio derived from dynamic CT-based myocardial perfusion imaging for the detection of haemodynamically relevant coronary artery stenosis. European radiology Coenen, A., Lubbers, M. M., Kurata, A., Kono, A., Dedic, A., Chelu, R. G., Dijkshoorn, M. L., Rossi, A., van Geuns, R. M., Nieman, K. 2016


    To investigate the additional value of transmural perfusion ratio (TPR) in dynamic CT myocardial perfusion imaging for detection of haemodynamically significant coronary artery disease compared with fractional flow reserve (FFR).Subjects with suspected or known coronary artery disease were prospectively included and underwent a CT-MPI examination. From the CT-MPI time-point data absolute myocardial blood flow (MBF) values were temporally resolved using a hybrid deconvolution model. An absolute MBF value was measured in the suspected perfusion defect. TPR was defined as the ratio between the subendocardial and subepicardial MBF. TPR and MBF results were compared with invasive FFR using a threshold of 0.80.Forty-three patients and 94 territories were analysed. The area under the receiver operator curve was larger for MBF (0.78) compared with TPR (0.65, P = 0.026). No significant differences were found in diagnostic classification between MBF and TPR with a territory-based accuracy of 77 % (67-86 %) for MBF compared with 70 % (60-81 %) for TPR. Combined MBF and TPR classification did not improve the diagnostic classification.Dynamic CT-MPI-based transmural perfusion ratio predicts haemodynamically significant coronary artery disease. However, diagnostic performance of dynamic CT-MPI-derived TPR is inferior to quantified MBF and has limited incremental value.• The transmural perfusion ratio from dynamic CT-MPI predicts functional obstructive coronary artery disease • Performance of the transmural perfusion ratio is inferior to quantified myocardial blood flow • The incremental value of the transmural perfusion ratio is limited.

    View details for DOI 10.1007/s00330-016-4567-0

    View details for PubMedID 27704198

  • Coronary angiography after cardiac arrest: Rationale and design of the COACT trial. American heart journal Lemkes, J. S., Janssens, G. N., Straaten, H. M., Elbers, P. W., van der Hoeven, N. W., Tijssen, J. G., Otterspoor, L. C., Voskuil, M., van der Heijden, J. J., Meuwissen, M., Rijpstra, T. A., Vlachojannis, G. J., van der Vleugel, R. M., Nieman, K., Jewbali, L. S., Bleeker, G. B., Baak, R., Beishuizen, B., Stoel, M. G., van der Harst, P., Camaro, C., Henriques, J. P., Vink, M. A., Gosselink, M. T., Bosker, H. A., Crijns, H. J., van Royen, N. 2016; 180: 39–45


    Ischemic heart disease is a major cause of out-of-hospital cardiac arrest. The role of immediate coronary angiography (CAG) and percutaneous coronary intervention (PCI) after restoration of spontaneous circulation following cardiac arrest in the absence of ST-segment elevation myocardial infarction (STEMI) remains debated.We hypothesize that immediate CAG and PCI, if indicated, will improve 90-day survival in post-cardiac arrest patients without signs of STEMI.In a prospective, multicenter, randomized controlled clinical trial, 552 post-cardiac arrest patients with restoration of spontaneous circulation and without signs of STEMI will be randomized in a 1:1 fashion to immediate CAG and PCI (within 2 hours) versus initial deferral with CAG and PCI after neurological recovery. The primary end point of the study is 90-day survival. The secondary end points will include 90-day survival with good cerebral performance or minor/moderate disability, myocardial injury, duration of inotropic support, occurrence of acute kidney injury, need for renal replacement therapy, time to targeted temperature control, neurological status at intensive care unit discharge, markers of shock, recurrence of ventricular tachycardia, duration of mechanical ventilation, and reasons for discontinuation of treatment.The COACT trial is a multicenter, randomized, controlled clinical study that will evaluate the effect of an immediate invasive coronary strategy in post-cardiac arrest patients without STEMI on 90-day survival.

    View details for DOI 10.1016/j.ahj.2016.06.025

    View details for PubMedID 27659881

  • Cardiac computed tomography in patients with acute chest pain EUROPEAN HEART JOURNAL Nieman, K., Hoffmann, U. 2015; 36 (15): 906-914


    The efficient and reliable evaluation of patients with acute chest pain is one of the most challenging tasks in the emergency department. Coronary computed tomography (CT) angiography may play a major role, since it permits ruling out coronary artery disease with high accuracy if performed with expertise in properly selected and prepared patients. Several randomized trials have established early cardiac CT as a viable safe and potentially more efficient alternative to functional testing in the evaluation of acute chest pain. Ongoing investigations explore whether advanced anatomic and functional assessments such as high-risk coronary plaque, resting myocardial perfusion, and left ventricular function, or the simulation of the fractional coronary flow reserve will add information to the anatomic assessment for stenosis, which would allow expanding the benefits of cardiac CT from triage to treatment decisions. Especially, the combination of high-sensitive troponins and coronary computed tomography angiography may play a valuable role in future strategies for the management of patients presenting with acute chest pain.

    View details for DOI 10.1093/eurheartj/ehv034

    View details for Web of Science ID 000353541800010

    View details for PubMedID 25687351

  • The Optimal Imaging Strategy for Patients With Stable Chest Pain A Cost-Effectiveness Analysis ANNALS OF INTERNAL MEDICINE Genders, T. S., Petersen, S. E., Pugliese, F., Dastidar, A. G., Fleischmann, K. E., Nieman, K., Hunink, M. G. 2015; 162 (7): 474-U145


    The optimal imaging strategy for patients with stable chest pain is uncertain.To determine the cost-effectiveness of different imaging strategies for patients with stable chest pain.Microsimulation state-transition model.Published literature.60-year-old patients with a low to intermediate probability of coronary artery disease (CAD).Lifetime.The United States, the United Kingdom, and the Netherlands.Coronary computed tomography (CT) angiography, cardiac stress magnetic resonance imaging, stress single-photon emission CT, and stress echocardiography.Lifetime costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios.The strategy that maximized QALYs and was cost-effective in the United States and the Netherlands began with coronary CT angiography, continued with cardiac stress imaging if angiography found at least 50% stenosis in at least 1 coronary artery, and ended with catheter-based coronary angiography if stress imaging induced ischemia of any severity. For U.K. men, the preferred strategy was optimal medical therapy without catheter-based coronary angiography if coronary CT angiography found only moderate CAD or stress imaging induced only mild ischemia. In these strategies, stress echocardiography was consistently more effective and less expensive than other stress imaging tests. For U.K. women, the optimal strategy was stress echocardiography followed by catheter-based coronary angiography if echocardiography induced mild or moderate ischemia.Results were sensitive to changes in the probability of CAD and assumptions about false-positive results.All cardiac stress imaging tests were assumed to be available. Exercise electrocardiography was included only in a sensitivity analysis. Differences in QALYs among strategies were small.Coronary CT angiography is a cost-effective triage test for 60-year-old patients who have nonacute chest pain and a low to intermediate probability of CAD.Erasmus University Medical Center.

    View details for DOI 10.7326/M14-0027

    View details for Web of Science ID 000353283400002

    View details for PubMedID 25844996

  • Cardiac computed tomography core syllabus of the European Association of Cardiovascular Imaging (EACVI) EUROPEAN HEART JOURNAL-CARDIOVASCULAR IMAGING Nieman, K., Achenbach, S., Pugliese, F., Cosyns, B., Lancellotti, P., Kitsiou, A. 2015; 16 (4): 351-352


    The European Association of Cardiovascular Imaging (EACVI) Core Syllabus for Cardiac Computed Tomography (CT) is now available online. The syllabus lists key elements of knowledge in Cardiac CT. It represents a framework for the development of training curricula and provides expected knowledge-based learning outcomes to the Cardiac CT trainees.

    View details for DOI 10.1093/ehjci/jeu298

    View details for Web of Science ID 000354716900002

    View details for PubMedID 25680383

  • Fractional Flow Reserve Computed from Noninvasive CT Angiography Data: Diagnostic Performance of an On-Site Clinician-operated Computational Fluid Dynamics Algorithm RADIOLOGY Coenen, A., Lubbers, M. M., Kurata, A., Kono, A., Dedic, A., Chelu, R. G., Dijkshoorn, M. L., Gijsen, F. J., Ouhlous, M., van Geuns, R. M., Nieman, K. 2015; 274 (3): 674-683


    To validate an on-site algorithm for computation of fractional flow reserve (FFR) from coronary computed tomographic (CT) angiography data against invasively measured FFR and to test its diagnostic performance as compared with that of coronary CT angiography.The institutional review board provided a waiver for this retrospective study. From coronary CT angiography data in 106 patients, FFR was computed at a local workstation by using a computational fluid dynamics algorithm. Invasive FFR measurement was performed in 189 vessels (80 of which had an FFR ≤ 0.80); these measurements were regarded as the reference standard. The diagnostic characteristics of coronary CT angiography-derived computational FFR, coronary CT angiography, and quantitative coronary angiography were evaluated against those of invasively measured FFR by using C statistics. Sensitivity and specificity were compared by using a two-sided McNemar test.For computational FFR, sensitivity was 87.5% (95% confidence interval [CI]: 78.2%, 93.8%), specificity was 65.1% (95% CI: 55.4%, 74.0%), and accuracy was 74.6% (95% CI: 68.4%, 80.8%), as compared with the finding of lumen stenosis of 50% or greater at coronary CT angiography, for which sensitivity was 81.3% (95% CI: 71.0%, 89.1%), specificity was 37.6% (95% CI: 28.5%, 47.4%), and accuracy was 56.1% (95% CI: 49.0%, 63.2%). C statistics revealed a larger area under the receiver operating characteristic curve (AUC) for computational FFR (AUC, 0.83) than for coronary CT angiography (AUC, 0.64). For vessels with intermediate (25%-69%) stenosis, the sensitivity of computational FFR was 87.3% (95% CI: 76.5%, 94.3%) and the specificity was 59.3% (95% CI: 47.8%, 70.1%).With use of a reduced-order algorithm, computation of the FFR from coronary CT angiography data can be performed locally, at a regular workstation. The diagnostic accuracy of coronary CT angiography-derived computational FFR for the detection of functionally important coronary artery disease (CAD) was good and was incremental to that of coronary CT angiography within a population with a high prevalence of CAD.

    View details for DOI 10.1148/radiol.14140992

    View details for Web of Science ID 000349990500006

    View details for PubMedID 25322342

  • Multislice computed tomography angiography for noninvasive assessment of the 18-month performance of a novel radiolucent bioresorbable vascular scaffolding device: the ABSORB trial (a clinical evaluation of the bioabsorbable everolimus eluting coronary stent system in the treatment of patients with de novo native coronary artery lesions). Journal of the American College of Cardiology Nieman, K., Serruys, P. W., Onuma, Y., van Geuns, R., Garcia-Garcia, H. M., De Bruyne, B., Thuesen, L., Smits, P. C., Koolen, J. J., McClean, D., Chevalier, B., Meredith, I., Ormiston, J. 2013; 62 (19): 1813-1814

    View details for DOI 10.1016/j.jacc.2013.07.030

    View details for PubMedID 23933536

  • Expert Consensus for Multi-Modality Imaging Evaluation of Cardiovascular Complications of Radiotherapy in Adults: A Report from the European Association of Cardiovascular Imaging and the American Society of Echocardiography JOURNAL OF THE AMERICAN SOCIETY OF ECHOCARDIOGRAPHY Lancellotti, P., Nkomo, V. T., Badano, L. P., Bergler, J., Bogaert, J., Davin, L., Cosyns, B., Coucke, P., Dulgheru, R., Edvardsen, T., Gaemperli, O., Galderisi, M., Griffin, B., Heidenreich, P. A., Nieman, K., Plana, J. C., Port, S. C., Scherrer-Crosbie, M., Schwartz, R. G., Sebag, I. A., Voigt, J., Wann, S., Yang, P. C. 2013; 26 (9): 1013-1032


    Cardiac toxicity is one of the most concerning side effects of anti-cancer therapy. The gain in life expectancy obtained with anti-cancer therapy can be compromised by increased morbidity and mortality associated with its cardiac complications. While radiosensitivity of the heart was initially recognized only in the early 1970s, the heart is regarded in the current era as one of the most critical dose-limiting organs in radiotherapy. Several clinical studies have identified adverse clinical consequences of radiation-induced heart disease (RIHD) on the outcome of long-term cancer survivors. A comprehensive review of potential cardiac complications related to radiotherapy is warranted. An evidence-based review of several imaging approaches used to detect, evaluate, and monitor RIHD is discussed. Recommendations for the early identification and monitoring of cardiovascular complications of radiotherapy by cardiac imaging are also proposed.

    View details for DOI 10.1016/j.echo.2013.07.005

    View details for Web of Science ID 000324028300003

    View details for PubMedID 23998694

  • Expert consensus for multi-modality imaging evaluation of cardiovascular complications of radiotherapy in adults: a report from the European Association of Cardiovascular Imaging and the American Society of Echocardiography EUROPEAN HEART JOURNAL-CARDIOVASCULAR IMAGING Lancellotti, P., Nkomo, V. T., Badano, L. P., Bergler, J., Bogaert, J., Davin, L., Cosyns, B., Coucke, P., Dulgheru, R., Edvardsen, T., Gaemperli, O., Galderisi, M., Griffin, B., Heidenreich, P. A., Nieman, K., Plana, J. C., Port, S. C., Scherrer-Crosbie, M., Schwartz, R. G., Sebag, I. A., Voigt, J., Wann, S., Yang, P. C. 2013; 14 (8): 721-740

    View details for DOI 10.1093/ehjci/jet123

    View details for Web of Science ID 000321833100001

    View details for PubMedID 23847385

  • Comparison of postprocessing techniques for the detection of perfusion defects by cardiac computed tomography in patients presenting with acute ST-segment elevation myocardial infarction JOURNAL OF CARDIOVASCULAR COMPUTED TOMOGRAPHY Rogers, I. S., Cury, R. C., Blankstein, R., Shapiro, M. D., Nieman, K., Hoffmann, U., Brady, T. J., Abbara, S. 2010; 4 (4): 258-266
  • A bioabsorbable everolimus-eluting coronary stent system (ABSORB): 2-year outcomes and results from multiple imaging methods LANCET Serruys, P. W., Ormiston, J. A., Onuma, Y., Regar, E., Gonzalo, N., Garcia-Garcia, H. M., Nieman, K., Bruining, N., Dorange, C., Miquel-Hebert, K., Veldhof, S., Webster, M., Thuesen, L., Dudek, D. 2009; 373 (9667): 897-910


    Drug-eluting metallic coronary stents predispose to late stent thrombosis, prevent late lumen vessel enlargement, hinder surgical revascularisation, and impair imaging with multislice CT. We assessed the safety of the bioabsorbable everolimus-eluting stent (BVS).30 patients with a single de-novo coronary artery lesion were followed up for 2 years clinically and with multiple imaging methods: multislice CT, angiography, intravascular ultrasound, derived morphology parameters (virtual histology, palpography, and echogenicity), and optical coherence tomography (OCT).Clinical data were obtained from 29 of 30 patients. At 2 years, the device was safe with no cardiac deaths, ischaemia-driven target lesion revascularisations, or stent thromboses recorded, and only one myocardial infarction (non-Q wave). 18-month multislice CT (assessed in 25 patients) showed a mean diameter stenosis of 19% (SD 9). At 2-year angiography, the in-stent late loss of 0.48 mm (SD 0.28) and the diameter stenosis of 27% (11) did not differ from the findings at 6 months. The luminal area enlargement on OCT and intravascular ultrasound between 6 months and 2 years was due to a decrease in plaque size without change in vessel size. At 2 years, 34.5% of strut locations presented no discernible features by OCT, confirming decreases in echogenicity and in radiofrequency backscattering; the remaining apparent struts were fully apposed. Additionally, vasomotion occurred at the stented site and adjacent coronary artery in response to vasoactive agents.At 2 years after implantation the stent was bioabsorbed, had vasomotion restored and restenosis prevented, and was clinically safe, suggesting freedom from late thrombosis. Late luminal enlargement due to plaque reduction without vessel remodelling needs confirmation.

    View details for Web of Science ID 000264158700031

    View details for PubMedID 19286089

  • Reliable noninvasive coronary angiography with fast submillimeter multislice spiral computed tomography CIRCULATION Nieman, K., Cademartiri, F., Lemos, P. A., Raaijmakers, R., Pattynama, P. M., de Feyter, P. J. 2002; 106 (16): 2051-2054


    Multislice spiral computed tomography (MSCT) is a promising technique for noninvasive coronary angiography, although clinical application has remained limited because of frequently incomplete interpretability, caused by motion artifacts and calcifications.In 59 patients (53 male, aged 58+/-12 years) with suspected obstructive coronary artery disease, ECG-gated MSCT angiography was performed with a 16-slice MSCT scanner (0.42-s rotation time, 12x0.75-mm detector collimation). Thirty-four patients were given additional beta-blockers (average heart rate: 56+/-6 min(-1)). After contrast injection, all data were acquired during an approximately 20-s breath hold. The left main (LM), left anterior descending (LAD), left circumflex (LCX), and right coronary artery (RCA), including > or =2.0-mm side branches, were independently evaluated by two blinded observers and screened for > or =50% stenoses. The consensus reading was compared with quantitative coronary angiography. MSCT was successful in 58 patients. Eighty-six of the 231 evaluated branches were significantly diseased. Without exclusion of branches, the sensitivity, specificity and positive and negative predictive value to identify > or =50% obstructed branches was 95% (82/86), 86% (125/145), 80% (82/102), and 97% (125/129), respectively. The overall accuracy for the LM, LAD, RCA, and LCX was 100%, 91%, 86%, and 81%, respectively. No obstructed LM, LAD, or RCA branches remained undetected. Classification of patients as having no, single, or multivessel disease was accurate in 78% (45/58) of patients and no patients with significant obstructions were incorrectly excluded.Improvements in MSCT technology, combined with heart rate control, allow reliable noninvasive detection of obstructive coronary artery disease.

    View details for DOI 10.1161/01.CIR.0000037222.58317.3D

    View details for Web of Science ID 000178683600007

    View details for PubMedID 12379572

  • Coronary angiography with multi-slice computed tomography LANCET Nieman, K., Oudkerk, M., Rensing, B. J., van Ooijen, P., Munne, A., van Geuns, R. J., de Feyter, P. J. 2001; 357 (9256): 599-603


    A new generation of subsecond multi-slice computed tomography (MSCT) scanners, which allow complete coronary coverage, are becoming widely available. We investigated the potential value of MSCT angiography in a range of coronary disorders.We studied 35 patients, including 11 who had undergone percutaneous transluminal coronary angioplasty and four who had had coronary-artery bypass grafts, by both MSCT and conventional coronary angiography. After intravenous injection of a non-ionic contrast medium with high iodine content, the entire heart was scanned within a single breath-hold. The total examination time was no more than 20 min. The retrospective electrocardiographically gated reconstruction source images and three-dimensional reconstructed volumes were analysed by two investigators, unaware of the results of conventional angiography.In the 31 patients without previous coronary surgery, 173 (73%) of the 237 proximal and middle coronary segments were assessable. In the assessable segments, 17 of 21 significant stenoses (>50% reduction of vessel diameter) were correctly diagnosed. The non-assessable segments included four lesions. Misinterpretations were mainly the result of severe calcification of the vessel wall. Segments with implanted stents were poorly visualised, but stent patency could be assessed in all cases. Of the 17 segments of bypass grafts, 15 were assessable and four of five graft lesions were detected. Two cases of anomalous coronary anatomy could be visualised well.These preliminary data suggest that MSCT allows non-invasive imaging of coronary-artery stenoses and has potential to develop into a reliable clinical technique.

    View details for Web of Science ID 000167119100013

    View details for PubMedID 11558487