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1.
Phase-III Clinical Trial of Fluorine-18 Flurpiridaz Positron Emission Tomography for Evaluation of Coronary Artery Disease.
Maddahi, J, Lazewatsky, J, Udelson, JE, Berman, DS, Beanlands, RSB, Heller, GV, Bateman, TM, Knuuti, J, Orlandi, C
Journal of the American College of Cardiology. 2020;(4):391-401
Abstract
BACKGROUND Fluorine-18 flurpiridaz is a novel positron emission tomography (PET) myocardial perfusion imaging tracer. OBJECTIVES This study sought to assess the diagnostic efficacy of flurpiridaz PET versus technetium-99m-labeled single photon emission computed tomography SPECT for the detection and evaluation of coronary artery disease (CAD), defined as ≥50% stenosis by quantitative invasive coronary angiography (ICA). Flurpiridaz safety was also evaluated. METHODS In this phase III prospective multicenter clinical study, 795 patients with known or suspected CAD from 72 clinical sites in the United States, Canada, and Finland were enrolled. A total of 755 patients were evaluable, and the mean age was 62.3 ± 9.5 years, 31% were women, 55% had body mass index ≥30 kg/m2, and 71% had pharmacological stress. Patients underwent 1-day rest-stress (pharmacological or exercise) flurpiridaz PET and 1- or 2-day rest-stress Tc-99m-labeled SPECT and ICA. Images were read by 3 experts blinded to clinical and ICA data. RESULTS Sensitivity of flurpiridaz PET (for detection of ≥50% stenosis by ICA) was 71.9% (95% confidence interval [CI]: 67.0% to 76.3%), significantly (p < 0.001) higher than SPECT (53.7% [95% CI: 48.5% to 58.8%]), while specificity did not meet the prespecified noninferiority criterion (76.2% [95% CI: 71.8% to 80.1%] vs. 86.6% [95% CI: 83.2% to 89.8%]; p = NS). Receiver-operating characteristic curve analysis demonstrated superior discrimination of CAD by flurpiridaz PET versus SPECT in the overall population, in women, obese patients, and patients undergoing pharmacological stress testing (p < 0.001 for all). Flurpiridaz PET was superior to SPECT for defect size (p < 0.001), image quality (p < 0.001), diagnostic certainty (p < 0.001), and radiation exposure (6.1 ± 0.4 mSv vs. 13.4 ± 3.2 mSv; p < 0.001). Flurpiridaz PET was safe and well tolerated. CONCLUSIONS Flurpiridaz PET myocardial perfusion imaging shows promise as a new tracer for CAD detection and assessment of women, obese patients, and patients undergoing pharmacological stress testing. A second phase III Food and Drug Administration trial is ongoing. (A Phase 3 Multi-center Study to Assess PET Imaging of Flurpiridaz F 18 Injection in Patients with CAD; NCT01347710).
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2.
Prognostic Value of Real Time Myocardial Contrast Echocardiography after Percutaneous Coronary Intervention.
Yang, L, Xia, C, Mu, Y, Guan, L, Wang, C, Tang, Q, Verocai, FG, Fonseca, LM, Shih, MC
Echocardiography (Mount Kisco, N.Y.). 2016;(3):421-30
Abstract
Real time myocardial contrast echocardiography (RTMCE) is a cost-effective and simple method to quantify coronary flow reserve (CFR). We aimed to determine the value of RTMCE to predict cardiac events after percutaneous coronary intervention (PCI). We have studied myocardial blood volume (A), velocity (β), flow indexes (MBF, A × β), and vasodilator reserve (stress-to-rest ratios) in 36 patients with acute coronary syndrome (ACS) who underwent PCI. CFR (MBF at stress/MBF at rest) was calculated for each patient. Perfusion scores were used for visual interpretation by MCE and correlation with TIMI flow grade. In qualitative RTMCE assessment, post-PCI visual perfusion scores were higher than pre-PCI (Z = -7.26, P < 0.01). Among 271 arteries with TIMI flow grade 3 post-PCI, 72 (36%) did not reach visual perfusion score 1. The β- and A × β-reserve of the abnormal segments supplied by obstructed arteries increased after PCI comparing to pre-PCI values (P < 0.01). Patients with adverse cardiac events had significantly lower β- and lower A × β-reserve than patients without adverse cardiac events. In the former group, the CFR was ≥ 1.5 both pre- and post-PCI. CFR estimation by RTMCE can quantify myocardial perfusion in patients with ACS who underwent PCI. The parameters β-reserve and CFR combined might predict cardiac events on the follow-up.
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3.
Simultaneous Assessment of Myocardial Perfusion, Wall Motion, and Deformation during Myocardial Contrast Echocardiography: A Feasibility Study.
Zoppellaro, G, Venneri, L, Khattar, RS, Li, W, Senior, R
Echocardiography (Mount Kisco, N.Y.). 2016;(6):889-95
Abstract
AIMS: Ultrasound contrast agents may be used for the assessment of regional wall motion and myocardial perfusion, but are generally considered not suitable for deformation analysis. The aim of our study was to assess the feasibility of deformation imaging on contrast-enhanced images using a novel methodology. METHODS AND RESULTS We prospectively enrolled 40 patients who underwent stress echocardiography with continuous intravenous infusion of SonoVue for the assessment of myocardial perfusion imaging with flash replenishment technique. We compared longitudinal strain (Lε) values, assessed with a vendor-independent software (2D CPA), on 68 resting contrast-enhanced and 68 resting noncontrast recordings. Strain analysis on contrast recordings was evaluated in the first cardiac cycles after the flash. Tracking of contrast images was deemed feasible in all subjects and in all views. Contrast administration improved image quality and increased the number of segments used for deformation analysis. Lε of noncontrast and contrast-enhanced images were statistically different (-18.8 ± 4.5% and -22.8 ± 5.4%, respectively; P < 0.001), but their correlation was good (ICC 0.65, 95%CI 0.42-0.78). Patients with resting wall-motion abnormalities showed lower Lε values on contrast recordings (-18.6 ± 6.0% vs. -24.2 ± 5.5%, respectively; P < 0.01). Intra-operator and inter-operator reproducibility was good for both noncontrast and contrast images with no statistical differences. CONCLUSIONS Our study shows that deformation analysis on postflash contrast-enhanced images is feasible and reproducible. Therefore, it would be possible to perform a simultaneous evaluation of wall-motion abnormalities, volumes, ejection fraction, perfusion defects, and cardiac deformation on the same contrast recording.
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4.
Value of CACS compared with ETT and myocardial perfusion imaging for predicting long-term cardiac outcome in asymptomatic and symptomatic patients at low risk for coronary disease: clinical implications in a multimodality imaging world.
Chang, SM, Nabi, F, Xu, J, Pratt, CM, Mahmarian, AC, Frias, ME, Mahmarian, JJ
JACC. Cardiovascular imaging. 2015;(2):134-44
Abstract
OBJECTIVES This prospective, observational study in 988 asymptomatic or symptomatic low-risk patients without prior coronary artery disease was conducted to define the relative value of coronary artery calcium score (CACS), exercise treadmill testing (ETT), and stress myocardial perfusion single-photon emission computed tomography (SPECT) variables in predicting long-term risk stratification. BACKGROUND CACS, ETT, and stress myocardial perfusion SPECT results predict patients' outcome. There are currently no data comparing their relative value in long-term risk stratification. METHODS Patients were stratified by Framingham risk score (FRS), with a median follow-up of 6.9 years. Cardiac events were defined as a composite of cardiac death, nonfatal myocardial infarction, and the need for coronary revascularization. Most patients (87%) were considered appropriate candidates for functional testing as defined by current appropriate use criteria. RESULTS The long-term cardiac event rate was 11.2% (1.6% per year). Multivariate risk predictors in all patients and in the appropriate use cohort were abnormal SPECT (hazard ratio [HR]: 1.83 and 1.99), ETT ischemia (HR: 1.70 and 1.76), decreasing exercise capacity (HR: 1.11 and 1.17), decreasing Duke treadmill score (HR: 1.07 for both), and CACS severity (HR: 1.29 for both), respectively. Throughout the 10-year follow-up, CACS improved risk prediction, with event rates ranging from 0.6% per year (CACS ≤10) to 3.7% per year (CACS >400) (p < 0.0001). CACS also improved risk prediction in all patients, in the appropriate use cohort and among those with low-risk ETT and SPECT results (all, p < 0.001). Area under the receiver-operating characteristic curve was increased when CACS variables (from 0.63 to 0.70; p = 0.01) but not ETT variables (from 0.63 to 0.65) were added to FRS. Moreover, net reclassification improvement was significantly increased when CACS was added to FRS + functional variables in all patients and in the appropriate use cohort (both, p < 0.0001). CONCLUSIONS CACS significantly improved long-term risk stratification beyond FRS, ETT, and SPECT results across the spectrum of clinical risk and importantly even among those who are currently considered appropriate candidates for functional testing or have low-risk functional test results. Our findings support CACS as a first-line test over ETT or SPECT for accurately assessing long-term risk in such patients.
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5.
Buccal caffeine for the routine reversal of Persantine.
Matangi, M, Dutchak, P
Journal of nuclear cardiology : official publication of the American Society of Nuclear Cardiology. 2014;(5):1039
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6.
Comparison between stress myocardial perfusion SPECT recorded with cadmium-zinc-telluride and Anger cameras in various study protocols.
Verger, A, Djaballah, W, Fourquet, N, Rouzet, F, Koehl, G, Imbert, L, Poussier, S, Fay, R, Roch, V, Le Guludec, D, et al
European journal of nuclear medicine and molecular imaging. 2013;(3):331-40
Abstract
PURPOSE The results of stress myocardial perfusion SPECT could be enhanced by new cadmium-zinc-telluride (CZT) cameras, although differences compared to the results with conventional Anger cameras remain poorly known for most study protocols. This study was aimed at comparing the results of CZT and Anger SPECT according to various study protocols while taking into account the influence of obesity. METHODS The study population, which was from three different institutions equipped with identical CZT cameras, comprised 276 patients referred for study using protocols involving (201)Tl (n = 120) or (99m)Tc-sestamibi injected at low dose at stress ((99m)Tc-Low; stress/rest 1-day protocol; n = 110) or at high dose at stress ((99m)Tc-High; rest/stress 1-day or 2-day protocol; n = 46). Each Anger SPECT scan was followed by a high-speed CZT SPECT scan (2 to 4 min). RESULTS Agreement rates between CZT and Anger SPECT were good irrespective of the study protocol (for abnormal SPECT, (201)Tl 92 %, (99m)Tc-Low 86 %, (99m)Tc-High 98 %), although quality scores were much higher for CZT SPECT with all study protocols. Overall correlations were high for the extent of myocardial infarction (r = 0.80) and a little lower for ischaemic areas (r = 0.72), the latter being larger on Anger SPECT (p < 0.001). This larger extent was mainly observed in 50 obese patients who were in the (201)Tl or (99m)Tc-Low group and in whom stress myocardial counts were particularly low with Anger SPECT (228 ± 101 kcounts) and dramatically enhanced with CZT SPECT (+279 ± 251 %). CONCLUSION Concordance between the results of CZT and Anger SPECT is good regardless of study protocol and especially when excluding obese patients who have low-count Anger SPECT and for whom myocardial counts are dramatically enhanced on CZT SPECT.
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7.
Absolute quantification of left ventricular global and regional function at nuclear MPI using ultrafast CZT SPECT: initial validation versus cardiac MR.
Cochet, H, Bullier, E, Gerbaud, E, Durieux, M, Godbert, Y, Lederlin, M, Coste, P, Barat, JL, Laurent, F, Montaudon, M
Journal of nuclear medicine : official publication, Society of Nuclear Medicine. 2013;(4):556-63
Abstract
UNLABELLED We sought to evaluate the accuracy of myocardial perfusion imaging (MPI) using cadmium-zinc-telluride (CZT) SPECT cameras for the measurement of left ventricular (LV) global and regional function, and the performance of absolute wall motion (WM) and wall thickness (WT) measurements for the detection of myocardial scarring, using cardiac MR as a reference. METHODS Sixty patients with known or suspected coronary artery disease underwent MPI using a CZT SPECT camera, as well as cine and delayed enhanced cardiac MR. Gated MPI data were processed using quantitative gated SPECT software. LV global function was assessed by measuring LV end-diastolic volume (EDV), end-systolic volume (ESV), and ejection fraction (EF). Regional function was assessed by quantifying segmental WM and WT according to the 17-segment model. Myocardial scarring was quantified on each segment using delayed enhanced cardiac MR. Agreement between SPECT and cardiac MR was assessed using Pearson correlation and Bland-Altman analyses. The influence of measurement magnitude on the agreement was analyzed using Spearman correlation coefficients between the mean and SD of measurements. The performance of WM and WT for the detection of segments with more than 25% scar transmurality was assessed using receiver-operating-characteristic analysis. RESULTS Correlation between methods was excellent for EF (R = 0.81, P < 0.0001) and ESV (R = 0.88, P < 0.0001) and was good for EDV (R = 0.71, P < 0.0001). Agreement was good for EF (bias, -2.7%; limits of agreement, -15.5 to +10.1) but was lower for EDV (bias, -29.7 mL; limits of agreement, -68.3 to +8.9) and ESV (bias, -9.9 mL; limits of agreement, -30.7 to +10.9). Correlation between methods was fair for WM (R = 0.49, P < 0.0001) and WT (R = 0.48, P < 0.0001). SPECT underestimated WT (bias, -41%; limits of agreement, -108 to +26), with an error depending on thickening magnitude (ρ = 0.70, P < 0.0001). The agreement in WM measurement was higher (bias, -1.4 mm; limits of agreement, -6.9 to +4) and independent of motion magnitude (ρ = 0.006, P = 0.86). WM and WT were equally able to identify scarred segments (area under the receiver-operating-characteristic curve, 0.74 ± 0.03 and 0.74 ± 0.03, respectively). CONCLUSION MPI using CZT SPECT cameras and quantitative gated SPECT analysis accurately quantifies EF but still underestimates LV volumes. WM shows a higher agreement with cardiac MR than does WT, with errors in WT measurement increasing at greater thicknesses. Absolute quantification of segmental WM and WT can equally be used to identify myocardial scarring.
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Cadmium-zinc-telluride myocardial perfusion imaging in obese patients.
Fiechter, M, Gebhard, C, Fuchs, TA, Ghadri, JR, Stehli, J, Kazakauskaite, E, Herzog, BA, Pazhenkottil, AP, Gaemperli, O, Kaufmann, PA
Journal of nuclear medicine : official publication, Society of Nuclear Medicine. 2012;(9):1401-6
Abstract
UNLABELLED We have evaluated the impact of increased body mass on the quality of myocardial perfusion imaging using a latest-generation γ-camera with cadmium-zinc-telluride semiconductor detectors in patients with high (≥40 kg/m(2)) or very high (≥45 kg/m(2)) body mass index (BMI). METHODS We enrolled 81 patients, including 18 with no obesity (BMI < 30 kg/m(2)), 17 in World Health Organization obese class I (BMI, 30-34.9 kg/m(2)), 15 in class II (BMI, 35-39.9 kg/m(2)), and 31 in class III (BMI ≥ 40 kg/m(2)), including 15 with BMI ≥ 45 kg/m(2). Image quality was scored as poor (1), moderate (2), good (3), or excellent (4). Patients with BMI ≥ 45 kg/m(2) and nondiagnostic image quality (≤2) were rescanned after repositioning to better center the heart in the field of view. Receiver-operating-curve analysis was applied to determine the BMI cutoff required to obtain diagnostic image quality (≥3). RESULTS Receiver-operating-curve analysis resulted in a cutoff BMI of 39 kg/m(2) (P < 0.001) for diagnostic image quality. In patients with BMI ≥ 40 kg/m(2), image quality was nondiagnostic in 81%; after CT-based attenuation correction this decreased to 55%. Repositioning further improved image quality. Rescanning on a conventional SPECT camera resulted in diagnostic image quality in all patients with BMI ≥ 45 kg/m(2). CONCLUSION Patients with BMI ≥ 40 kg/m(2) should be scheduled for myocardial perfusion imaging on a conventional SPECT camera, as it is difficult to obtain diagnostic image quality on a cadmium-zinc-telluride camera.
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Reduced heart rate response to dipyridamole in patients undergoing myocardial perfusion SPECT.
Gorur, GD, Ciftci, EA, Kozdag, G, Isgoren, S, Oc, MA, Haksal, C, Gur, M, Demir, H
Annals of nuclear medicine. 2012;(8):609-15
Abstract
OBJECTIVE A mild decrease in blood pressure and increase in heart rate (HR) are considered normal hemodynamic responses to dipyridamole. In this study, we tried to investigate HR response to dipyridamole and its predictors in patients undergoing gated myocardial perfusion single photon emission computed tomography (SPECT). METHODS 201 consecutive patients undergoing dipyridamole stress Tc99m-MIBI or Tl-201 gated myocardial perfusion SPECT were prospectively enrolled. Dipyridamole was infused over 4 min and radiopharmaceutical was injected 3 min after the end of infusion. A reduced heart rate response to dipyridamole considered if the HR ratio (peak HR/rest HR) was 1.20 or less. Stress (sLVEF), rest (rLVEF) left ventricular ejection fractions, stress and rest motion (SMS, RMS) and thickening scores (STS, RTS) were derived automatically by QGS. Summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS) for myocardial perfusion were calculated. Patients were grouped according to HR response and groups were compared. A logistic regression analysis was used to determine independent predictors of reduced HR response. RESULTS Reduced HR response was found in 78 % of patients. Patients with abnormal HR response were more frequently had a history of diabetes mellitus, chronic renal failure, and had lower high-density lipoprotein (HDL) levels. Peak HR, SSS, SRS, sLVEF and rLVEF were lower; rest HR, RTS, and the number of patients with ≤ 45 % sLVEF and rLVEF were higher in reduced HR response group (all p < 0.05). There was no difference between groups by means of gender, rest and peak systolic or diastolic tension, SDS, SMS, STS, RMS, history of hypertension, peripheral arterial disease, metabolic syndrome, coronary interventions, digoxin, calcium channel blocker or beta blocker usage. Multivariable logistic regression analysis demonstrated that the independent predictors of reduced HR response were HDL, rest HR and SSS. When HDL was removed from the model, chronic renal failure also emerged as an independent predictor. CONCLUSION Reduced HR response to dipyridamole is associated with ventricular dysfunction, cardiac autonomic neuropathy. Low HDL levels also seem to be related with reduced HR response.
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10.
The impact of plaque characterization assessed by intravascular ultrasound on myocardial perfusion after primary angioplasty in patients With ST-segment elevation myocardial infarction.
Nakata, T, Fujii, K, Fukunaga, M, Kawasaki, D, Kawabata-Lee, M, Masutani, M, Ohyanagi, M, Masuyama, T
Circulation journal : official journal of the Japanese Circulation Society. 2011;(11):2642-7
Abstract
BACKGROUND Previous studies described that inadequate tissue perfusion after primary angioplasty in ST-elevation myocardial infarction (STEMI) patients is associated with adverse cardiac events. This study evaluated whether plaque morphological intravascular ultrasound (IVUS) characteristics affects tissue perfusion after stent implantation in STEMI patients. METHODS AND RESULTS A total of consecutive 306 STEMI patients who underwent primary angioplasty with IVUS were analyzed. Maximum ST-segment elevation before angioplasty was compared with ST-segment levels 60min after angioplasty. Percent ST-segment resolution (STR) was calculated and categorized as complete (>70%), partial (30-70%), and absent (<30%). Qualitative and quantitative IVUS analyses were performed using standard methods. Plaque with ultrasound attenuation was defined as IVUS finding with backward signal attenuation behind plaque >180° without dense calcium. One-hundred-fifty patients had complete, 101 had partial, and 55 had absent STR. The incidence of in-hospital death tended to be higher in absent STR than in partial and complete STR groups. Multivariate analysis indicated that remodeling index (P=0.004), the presence of ultrasound attenuation (P=0.02), percentage stent expansion (P=0.03), and the presence of deep calcium (P=0.049) were the independent predictors related to the occurrence of absent STR after angioplasty. CONCLUSIONS Positive vessel remodeling, plaque with ultrasound attenuation >180°, deep calcium, and stent overexpansion as assessed by IVUS are associated with the absence of STR after primary angioplasty in patients with STEMI.