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Kai Hang Yiu,
Fleur R de Graaf,
Joanne D Schuijf,
Jacob M van Werkhoven,
Nina Ajmone Marsan,
Caroline E Veltman,
Albert de Roos, Aju Pazhenkottil,
Lucia J Kroft,
Eric Boersma,
Bernhard Herzog,
Melissa Leung,
Erica Maffei,
Dominic Y Leung,
Philipp A Kaufmann,
Filippo Cademartiri,
Jeroen J Bax,
J Wouter Jukema
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ABSTRACT: To evaluate the potential age- and gender-specific differences in the incidence and prognostic value of coronary artery disease (CAD) in patients undergoing CT coronary angiography (CTA).
In this multicentre prospective registry study, 2432 patients (mean age 57 ± 12, 56% male) underwent CTA for suspected CAD. Patients were stratified into four groups according to age <60 or ≥60 years and, male or female gender.
A composite end point of cardiac death and non-fatal myocardial infarction.
CTA results were normal in 991 (41%) patients, showed non-significant CAD in 761 (31%) patients and significant CAD in the remaining 680 (28%) patients. During follow-up (median 819 days, 25-75th centile 482-1142) a cardiovascular event occurred in 59 (2.4%) patients. The annualised event rate was 1.1% in the total population (men=1.3% and women=0.9%). In patients aged <60 years, the annualised event rate of male and female patients was 0.6% and 0.5%, respectively. Among patients aged ≥60 years the annualised event rate was 1.9% in male and 1.1% in female patients. Observations on CTA predicted events in male patients, both age <60 and ≥60 years and in female patients age ≥60 years (log-rank test in all groups, p<0.01). However, CTA provided limited prognostic value in female patients aged <60 years (log-rank test, p=0.45).
After age and gender stratification, CTA findings were shown to be of limited predictive value in female patients aged <60 years as compared with male patients at any age and female patients aged ≥60 years.
Heart (British Cardiac Society) 09/2011; 98(3):232-7. · 4.22 Impact Factor
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Kai Hang Yiu,
Fleur R de Graaf,
Joanne D Schuijf,
Jacob M van Werkhoven,
Joella E van Velzen,
Mark J Boogers,
Cornelis J Roos,
Mihály K de Bie, Aju Pazhenkottil,
Lucia J Kroft,
Eric Boersma,
Bernhard Herzog,
Albert de Roos,
Philipp A Kaufmann,
Jeroen J Bax,
J Wouter Jukema
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ABSTRACT: Chronic kidney disease (CKD) is associated with cardiovascular (CV) events caused by advanced atherosclerosis. Computed tomographic coronary angiography (CTA) can accurately diagnose coronary artery disease (CAD) and predict CV outcomes. The aim of the present study was to evaluate whether moderate CKD provides prognostic information for CV events in patients undergoing CTA. In total 885 patients with suspected CAD underwent CTA and were stratified to moderate CKD (85 patients) or no CKD (770 patients) based on a cut-off estimated glomerular filtration rate of 60 ml/min/1.73 m(2). After 896 days of follow-up, 42 patients developed CV events. Annualized CV event rates were 1.2% in patients with no CKD and no CAD, 2.5% in patients with moderate CKD alone, 2.5% in patients with obstructive CAD alone, and 3.7% in those with moderate CKD and obstructive CAD. Multivariate models demonstrated that moderate CKD (hazard ratio 2.39, confidence interval 1.09 to 5.21, p = 0.03) and obstructive CAD (hazard ratio 2.76, confidence interval 1.40 to 5.44, p <0.01) were independent predictors of CV events. Importantly, moderate CKD provided incremental prognostic information in addition to clinical characteristics and obstructive CAD (chi-square 49.4, p = 0.04). In conclusion, moderate CKD was associated with CV events and provided incremental prognostic information.
The American journal of cardiology 07/2011; 108(7):968-72. · 3.58 Impact Factor
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ABSTRACT: In this work Linear Response Equilibrium (LRE) and Echo-planar spectroscopic imaging (EPSI) are compared in terms of sensitivity per unit time and power deposition. In addition an extended dual repetition time scheme to generate broad stopbands for improved inherent water suppression in LRE is presented. The feasibility of LRE and EPSI for assessing cholesterol esters in human carotid plaques with high spatial resolution of 1.95×1.15×1.15 mm(3) on a clinical 3T MR system is demonstrated. In simulations and phantom experiments it is shown that LRE has comparable but lower sensitivity per unit time relative to EPSI despite stronger signal generated. This relates to the lower sampling efficiency in LRE relative to EPSI as a result of limited gradient performance on clinical MR systems. At the same time, power deposition of LRE is significantly reduced compared to EPSI making it an interesting niche application for in vivo high field spectroscopic imaging of metabolites within a limited bandwidth.
Journal of Magnetic Resonance 07/2011; 211(1):80-8. · 2.14 Impact Factor
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Ines Valenta,
Valerie Treyer,
Lars Husmann,
Oliver Gaemperli,
Michael J Schindler,
Bernhard A Herzog,
Patrick Veit-Heibach,
Ronny R Buechel,
René Nkoulou, Aju P Pazhenkottil,
Philipp A Kaufmann
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ABSTRACT: Shortening scan time and/or reducing radiation dose at maintained image quality are the main issues of the current research in radionuclide myocardial perfusion imaging (MPI). We aimed to validate a new iterative reconstruction (IR) algorithm for SPECT MPI allowing shortened acquisition time (HALF time) while maintaining image quality vs. standard full time acquisition (FULL time).
In this study, 50 patients, referred for evaluation of known or suspected coronary artery disease by SPECT MPI using 99mTc-Tetrofosmin, underwent 1-day adenosine stress 300 MBq/rest 900 MBq protocol with standard (stress 15 min/rest 15 min FULL time) immediately followed by short emission scan (stress 9 min/rest 7 min HALF time) on a Ventri SPECT camera (GE Healthcare). FULL time scans were processed with IR, short scans were additionally processed with a recently developed software algorithm for HALF time emission scans. All reconstructions were subsequently analyzed using commercially available software (QPS/QGS, Cedars Medical Sinai) with/without X-ray based attenuation correction (AC). Uptake values (percent of maximum) were compared by regression and Bland-Altman (BA) analysis in a 20-segment model.
HALF scans yielded a 96% readout and 100% clinical diagnosis concordance compared to FULL. Correlation for uptake in each segment (n = 1,000) was r = 0.87at stress (p < 0.001) and r = 0.89 at rest (p < 0.001) with respective BA limits of agreement of -11% to 10% and -12% to 11%. After AC similar correlation (r = 0.82, rest; r = 0.80, stress, both p < 0.001) and BA limits were found (-12% to 10%; -13% to 12%).
With the new IR algorithm, SPECT MPI can be acquired at half of the scan time without compromising image quality, resulting in an excellent agreement with FULL time scans regarding to uptake and clinical conclusion.
European Journal of Nuclear Medicine 11/2009; 37(4):750-7. · 4.53 Impact Factor
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ABSTRACT: To validate a new low-dose and rapid stepwise individualized algorithm for non-invasive assessment of ischemic coronary artery disease by sequential use of prospectively ECG-triggered low-dose CT coronary angiography (CTCA) and low-dose single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI).
Forty patients referred for elective invasive coronary angiography (CA) were prospectively enrolled to undergo a comprehensive non-invasive evaluation with low-dose CTCA and a dose-reduced stress/rest SPECT-MPI scan (using dedicated reconstruction algorithms for low count scans). The following algorithm was reviewed: CTCA first, followed by a stress-only MPI if a coronary stenosis (> or = 50% diameter narrowing) or equivocal findings were observed. Only abnormal stress MPI scans were followed by rest MPI. The accuracy of the individualized algorithm to predict coronary revascularization and its mean effective radiation dose were assessed.
CTCA documented CAD in 18 and equivocal findings in two patients, thus, requiring additional stress MPI scans. Of these, 16 were abnormal, therefore requiring a rest MPI scan, revealing ischemia in 15 patients. Sensitivity, specificity, negative and positive predictive value, and accuracy of the individualized algorithm for predicting coronary revascularization was 93.3%, 96.0%, 96.0%, 93.3% and 95.0% on a per-patient base. The mean effective radiation dose was significantly lower for the individualized (4.8 +/- 3.4 mSv) versus the comprehensive method (8.1 +/- 1.5 mSv) resulting in a total population radiation dose reduction of 132.6 mSv.
This new individualized low-dose algorithm allows rapid and accurate prediction of invasive CA findings and of treatment decision with minimized radiation dose.
European Journal of Nuclear Medicine 09/2009; 37(3):522-7. · 4.53 Impact Factor
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Lars Husmann,
Fuminari Tatsugami,
Ursina Aepli,
Bernhard A Herzog,
Ines Valenta,
Patrick Veit-Haibach,
Ronny R Buechel, Aju P Pazhenkottil,
Oliver Gaemperli,
Nina Burkhard,
Christophe A Wyss,
Philipp A Kaufmann
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ABSTRACT: Electrocardiogram (ECG)-triggered, low dose computed tomography (CT) is increasingly used for attenuation correction in myocardial perfusion imaging (MPI) with SPECT. The purpose of the study was to assess the prevalence of relevant noncardiac findings in the field-of-view of such attenuation correction CT scans. Five hundred and eighty-two consecutive patients (211 female, 371 male; mean age: 64 +/- 11 years; BMI: 27.7 +/- 5.3 kg/m(2)) underwent 64-slice, ECG-triggered CT scanning for attenuation correction of MPI with SPECT. Relevant findings were defined as abnormalities that required clinical or radiological follow-up. Noncardiac findings were detected in 400 patients (68.7%). In 196 patients (33.7%) 226 relevant findings were detected. Findings included noncalcified pulmonary nodules (n = 156), interstitial lung disease (n = 6), pleural effusion (n = 20), pneumonia (n = 1), aortic aneurysm (n = 5), aortic dissection (n = 4), enlarged mediastinal lymph nodes (n = 5), mediastinal tumor (n = 3), breast abnormalities (n = 3), liver cirrhosis (n = 5), liver mass (n = 5), ascites (n = 5), splenomegaly (n = 2), renal mass (n = 1), hydronephrosis (n = 1), adrenal mass (n = 3), and bone metastasis (n = 1). As low dose 64-slice CT scans used for attenuation correction in MPI with SPECT reveal a high prevalence of noncardiac pathologic findings with potential clinical relevance, a systematic review of the CT scans appears mandatory.
The international journal of cardiovascular imaging 09/2009; 25(8):859-65. · 2.15 Impact Factor
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Jacob M van Werkhoven,
Joanne D Schuijf,
Oliver Gaemperli,
J Wouter Jukema,
Lucia J Kroft,
Eric Boersma, Aju Pazhenkottil,
Ines Valenta,
Gabija Pundziute,
Albert de Roos,
Ernst E van der Wall,
Philipp A Kaufmann,
Jeroen J Bax
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ABSTRACT: The purpose of this study was to assess the relationship between calcium scoring (CS) and multi-slice computed tomography coronary angiography (MSCTA) and to determine if MSCTA has an incremental prognostic value to CS.
In 432 patients (59% male, age 58 +/- 11 years) referred for cardiac evaluation owing to suspected coronary artery disease (CAD), CS and 64-slice MSCTA were performed. The following events were combined in a composite endpoint: all-cause mortality, non-fatal infarction, and unstable angina requiring revascularization. CS was 0 in 147 (34%) patients, CS 1-99 was present in 122 (28%), CS 100-399 in 75 (17%), CS 400-999 in 56 (13%), and CS > or = 1000 in 32 (7%). MSCTA was normal in 133 (31%) patients, MSCTA 30-50% stenosis was observed in 190 (44%), and MSCTA > or =50% stenosis in 109 (25%). During follow-up [median 670 days (25th-75th percentile: 418-895)], an event occurred in 21 patients (4.9%). After multivariate correction for CS, MSCTA > or = 50% stenosis, the number of diseased segments, obstructive segments, and non-calcified plaques were independent predictors with an incremental prognostic value to CS.
MSCTA provides additional information to CS regarding stenosis severity and plaque composition. This additional information was shown to translate into incremental prognostic value over CS.
European Heart Journal 07/2009; 30(21):2622-9. · 10.48 Impact Factor
