ABSTRACT
PURPOSE: Study aims to investigate the consistency of delayed enhancement cardiac magnetic resonance imaging (DE-CMR) and 18F-FDG PET myocardial imaging in evaluating myocardial viability before CABG. METHODS: The study analyzed data from 100 patients who were examined with DE-CMR, PET imaging, and echocardiography before and after CABG. All subjects were followed up for 6-12 month post- CABG. RESULTS: DE-CMR and PET imaging have high consistency (90.1%; Kappa value = 0.71, p < 0.01) in determining myocardial viability. The degree of delayed enhancement was negatively correlated with the improvement in myocardial contractile function in this segment after revascularization (P < 0.001). The ratio of scarred myocardial segments and total DE score was significantly lower in the improvement group than non-improvement group. Multivariate regression identified that hibernating myocardium (OR = 1.229, 95%CI: 1.053-1.433, p = 0.009) was influencing factor of LVEF improvement after CABG. CONCLUSION: Both imaging techniques are consistent in evaluating myocardial viability. Detecting the number of hibernating myocardium by PET is also important to predict the left heart function improvement after CABG.
Subject(s)
Coronary Artery Bypass , Coronary Artery Disease , Fluorodeoxyglucose F18 , Myocardial Perfusion Imaging , Myocardium , Positron-Emission Tomography , Predictive Value of Tests , Radiopharmaceuticals , Tissue Survival , Ventricular Function, Left , Humans , Male , Female , Middle Aged , Fluorodeoxyglucose F18/administration & dosage , Myocardium/pathology , Radiopharmaceuticals/administration & dosage , Aged , Myocardial Perfusion Imaging/methods , Time Factors , Treatment Outcome , Coronary Artery Disease/diagnostic imaging , Coronary Artery Disease/physiopathology , Coronary Artery Disease/surgery , Coronary Artery Disease/therapy , Recovery of Function , Stroke Volume , Reproducibility of Results , Myocardial Stunning/diagnostic imaging , Myocardial Stunning/physiopathology , Myocardial Stunning/etiology , Multimodal Imaging , Magnetic Resonance Imaging , Myocardial Contraction , Coronary Circulation , Retrospective StudiesABSTRACT
AIMS: Neurogenic stunned myocardium (NSM) has heterogeneous presentations for acute ischemic stroke (AIS) and aneurysmal subarachnoid hemorrhage (SAH). We sought to better define NSM and differences between AIS and SAH by evaluating individual left ventricular (LV) functional patterns by speckle tracking echocardiography (STE). METHODS: We evaluated consecutive patients with SAH and AIS. Via STE, LV longitudinal strain (LS) values of basal, mid, and apical segments were averaged and compared. Different multivariable logistic regression models were created by defining stroke subtype (SAH or AIS) and functional outcome as dependent variables. RESULTS: One hundred thirty-four patients with SAH and AIS were identified. Univariable analyses using the chi-squared test and independent samples t-test identified demographic variables and global and regional LS segments with significant differences. In multivariable logistic regression analysis, when comparing AIS to SAH, AIS was associated with older age (OR 1.07, 95% CI 1.02-1.13, p = 0.01), poor clinical condition on admission (OR 7.74, 95% CI 2.33-25.71, p < 0.001), decreased likelihood of elevated admission serum troponin (OR .09, 95% CI .02-.35, p < 0.001), and worse LS basal segments (OR 1.18, 95% CI 1.02-1.37, p = 0.03). CONCLUSION: In patients with neurogenic stunned myocardium, significantly impaired LV contraction by LS basal segments was found in patients with AIS but not with SAH. Individual LV segments in our combined SAH and AIS population were also not associated with clinical outcomes. Our findings suggest that strain echocardiography may identify subtle forms of NSM and help differentiate the NSM pathophysiology in SAH and AIS.
Subject(s)
Ischemic Stroke , Myocardial Stunning , Subarachnoid Hemorrhage , Humans , Subarachnoid Hemorrhage/complications , Subarachnoid Hemorrhage/diagnostic imaging , Myocardial Stunning/diagnostic imaging , Myocardial Stunning/etiology , Ischemic Stroke/complications , Heart , EchocardiographySubject(s)
Myocardial Ischemia/physiopathology , Myocardial Stunning/physiopathology , Ventricular Dysfunction, Left/physiopathology , Ventricular Function, Left , Animals , Calcium Signaling , Humans , Myocardial Ischemia/diagnostic imaging , Myocardial Ischemia/metabolism , Myocardial Ischemia/therapy , Myocardial Stunning/diagnostic imaging , Myocardial Stunning/metabolism , Myocardial Stunning/therapy , Myocardium/metabolism , Prognosis , Reactive Oxygen Species/metabolism , Recovery of Function , Ventricular Dysfunction, Left/diagnostic imaging , Ventricular Dysfunction, Left/metabolism , Ventricular Dysfunction, Left/therapySubject(s)
Myocardial Stunning , Takotsubo Cardiomyopathy , Chest Pain , Coronary Angiography , Coronary Vessels/diagnostic imaging , Humans , Myocardial Stunning/diagnostic imaging , Myocardial Stunning/etiology , Perfusion Imaging , Spasm , Takotsubo Cardiomyopathy/diagnostic imaging , Tomography, X-Ray ComputedABSTRACT
AIM AND PATIENTS: The aim of the present study was to assess the additional value of systolic wall thickening to myocardial perfusion in diagnosing myocardial stunning induced by dipyridamole infusion. We selected 52 ischemic patients (43 males; mean age 65.5 ± 7.64), with CAD documented by angiography. Ischemia was defined as a summed difference score ≥ 5. All patients underwent a 2-day gated perfusion SPECT protocol. The patients received a dose of 740 MBq of 99mTc-tetrofosmin after stress and at rest. RESULTS: The post-stress LVEF was significantly lower than rest LVEF (48.3% ± 14.5% vs. 50.7% ± 15%; P = 0.0001). The wall thickening summed difference score was 3.97 ± 3.84 (P = 0.0001). At a multivariate regression analysis, only WT-SDS as independent variable was significantly correlated with myocardial ischemia (SDS) (P = 0.001). We divided patients according to SDS in those with mild (SDS < 8) and severe (SDS ≥ 8) ischemia. WT-SDS, but not ∆LVEF, was significantly different between groups. CONCLUSIONS: WT-SDS showed a better correlation with the degree of ischemia than the depression in the global function of the left ventricle. It allowed to better identify the stunning phenomenon in patients submitted to pharmacological stress.
Subject(s)
Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography , Myocardial Ischemia/diagnostic imaging , Myocardial Stunning/diagnostic imaging , Aged , Dipyridamole , Female , Humans , Male , Middle Aged , Myocardial Ischemia/complications , Myocardial Ischemia/physiopathology , Myocardial Stunning/etiology , Organophosphorus Compounds , Organotechnetium Compounds , Predictive Value of Tests , Radiopharmaceuticals , Vasodilator AgentsABSTRACT
BACKGROUND: Previous studies have demonstrated left ventricular mechanical dyssynchrony (LVMD) in patients with severe coronary artery disease (CAD) with ≥ 70% stenosis. The aim of this study was to evaluate the clinical usefulness of stress/rest LVMD in the diagnosis of CAD with ≥ 50% stenosis using dipyridamole thallium-201 (Tl-201) myocardial perfusion imaging (MPI) with a cadmium-zinc-telluride camera. METHODS AND RESULTS: A total of 476 patients without known CAD who underwent dipyridamole Tl-201 MPI and coronary angiography within 6 months were retrospectively reviewed. LVMD parameters including phase standard deviation and phase histogram bandwidth, phase skewness and phase kurtosis, as well as myocardial perfusion and myocardial stunning were assessed in post-stress and rest MPI. Relationships between the presence of CAD on coronary angiography and single photon emission computerized tomography (SPECT) parameters were evaluated. The presence of perfusion abnormalities was the best diagnostic tool in detecting CAD. Although less left ventricular synchrony was observed post-stress in the CAD group compared to the non-CAD group, no significant dyssynchrony was noted. CONCLUSIONS: The addition of phase analysis to help diagnose CAD in Tl-201-gated SPECT with dipyridamole stress may have limited value in patients with CAD with ≥ 50% stenosis.
Subject(s)
Cardiac-Gated Single-Photon Emission Computer-Assisted Tomography , Coronary Artery Disease/diagnostic imaging , Myocardial Perfusion Imaging , Myocardial Stunning/diagnostic imaging , Thallium Radioisotopes , Aged , Cadmium , Coronary Angiography , Coronary Artery Disease/etiology , Coronary Artery Disease/physiopathology , Dipyridamole , Female , Humans , Male , Middle Aged , Myocardial Stunning/etiology , Myocardial Stunning/physiopathology , Tellurium , Vasodilator Agents , Ventricular Function , ZincABSTRACT
The transient left atrial appendage (LAA) dysfunction after electrical cardioversion (CV), which is called as LAA-stunning, was found to be an important etiology of thrombus formation. The aim of the present study was to investigate the risk factors of LAA-stunning. This study included 134 patients who underwent catheter ablation for non-paroxysmal, non-valvular, and symptomatic atrial fibrillation (AF). Internal-CV was performed, and LAA emptying fraction (LAA-EF) was assessed using LAA-angiogram before and just after CV. LAA-stunning (defined as 10% reduction of LAA-EF after CV) was observed in 45/134 patients (34%). Patients in LAA-stunning group had longer duration of AF prior to CV, higher brain natriuretic peptide (BNP), higher prevalence of patients taking calcium blocker, larger left atrial (LA) diameter, elevated E wave, and larger LA volume than those in non LAA-stunning group. Multivariate analysis showed that longer duration of AF prior to CV (p = 0.015, OR 1.033 for 1 month extend, 95% CI 1.006-1.073) and elevated BNP (p = 0.038, OR 1.041 for each 10 pg/mL increase, 95% CI 1.001-1.009) were associated with LAA-stunning. In addition, all patients were divided into four groups based on the combination between duration of AF prior to CV and BNP; group 1 (low BNP/short-lasting AF), group 2 (high BNP/short-lasting AF), group 3 (low BNP/long-lasting AF), and group 4 (high BNP/long-lasting AF). The rate of LAA-stunning was the highest in the group 4 (55.6%). Elevated BNP and long duration of AF were associated with LAA stunning after electrical cardioversion.
Subject(s)
Atrial Appendage/physiopathology , Atrial Fibrillation/therapy , Atrial Function, Left , Electric Countershock/adverse effects , Myocardial Stunning/etiology , Aged , Anti-Arrhythmia Agents/administration & dosage , Atrial Appendage/diagnostic imaging , Atrial Fibrillation/diagnostic imaging , Atrial Fibrillation/physiopathology , Biomarkers/blood , Calcium Channel Blockers/administration & dosage , Drug Administration Schedule , Echocardiography , Electrophysiologic Techniques, Cardiac , Female , Humans , Male , Middle Aged , Myocardial Stunning/diagnostic imaging , Myocardial Stunning/physiopathology , Natriuretic Peptide, Brain/blood , Risk Assessment , Risk Factors , Time Factors , Treatment Outcome , Up-RegulationABSTRACT
AIM AND PATIENTS: The aim of the present study is to evaluate the additional value of systolic wall thickening to myocardial perfusion in diagnosing myocardial stunning in patients with angiography proven coronary artery disease. We selected 91 ischemic patients (82 males; mean age 59.7 ± 10.3) with CAD documented by angiography. Ischemia was defined as a summed difference score ≥5. All patients underwent a 2-day gated perfusion SPECT protocol. The patients received a dose of 740 MBq of 99mTc-tetrofosmin after stress and at rest. Treadmill maximal exercise tests were performed on all patients. RESULTS: The post-stress LVEF was significantly lower than rest LVEF (48.1% ± 10.3% vs 50.3% ± 10.7%; P = .0001). The wall thickening summed difference score was 4.44 ± 4.13 (P = .0001). At a multivariate regression analysis, only WT-SDS as independent variable was significantly correlated with myocardial ischemia (SDS). We also divided patients according to SDS in those with mild (SDS < 8) and severe (SDS ≥ 8) ischemia. WT-SDS, but not ∆LVEF, was significantly different between groups. CONCLUSIONS: WT-SDS, more than the depression in the global function (∆LVEF) of the left ventricle, correlates with the degree of ischemia and better identifies, when present, the stunning phenomenon.
Subject(s)
Coronary Artery Disease/diagnostic imaging , Exercise Test , Gated Blood-Pool Imaging , Myocardial Stunning/diagnostic imaging , Tomography, Emission-Computed, Single-Photon , Aged , Coronary Artery Disease/complications , Coronary Circulation , Female , Humans , Male , Middle Aged , Myocardial Stunning/etiology , Predictive Value of Tests , Stroke VolumeABSTRACT
AIMS: Left-ventricular (LV) scarring may be associated with a poor response to cardiac resynchronization therapy (CRT). The automatic analysis of myocardial perfusion single-photon emission computed tomography (MP-SPECT) may provide objective quantification of LV scarring. We investigated the impact of LV scarring determined by an automatic analysis of MP-SPECT on short-term LV volume response as well as long-term outcome. METHODS AND RESULTS: We studied consecutive 51 patients who were eligible to undergo 99mTc-MIBI MP-SPECT both at baseline and 6 months after CRT (ischaemic cardiomyopathies 31%). Quantitative perfusion SPECT was used to evaluate the defect extent (an index of global scarring) and the LV 17-segment regional uptake ratio (an inverse index of regional scar burden). The primary outcome was the composite of overall mortality or first hospitalization for worsening heart failure. A high global scar burden and a low mid/basal inferolateral regional uptake ratio were associated with volume non-responders to CRT at 6 months. The basal inferolateral regional uptake ratio remained as a predictor of volume non-response after adjusting for the type of cardiomyopathy. During a median follow-up of 36.1 months, the outcome occurred in 28 patients. The patients with a low basal inferolateral regional uptake ratio with a cutoff value of 57% showed poor prognosis (log-rank P= 0.006). CONCLUSION: The scarring determined by automatic analysis of MP-SPECT images may predict a poor response to CRT regardless of the pathogenesis of cardiomyopathy. The basal inferolateral scar burden in particular may have an adverse impact on long-term prognosis.
Subject(s)
Cardiac Resynchronization Therapy/mortality , Heart Failure/mortality , Heart Failure/prevention & control , Technetium Tc 99m Sestamibi , Tomography, Emission-Computed, Single-Photon/statistics & numerical data , Ventricular Dysfunction, Left/diagnostic imaging , Ventricular Dysfunction, Left/mortality , Aged , Cardiac Resynchronization Therapy/statistics & numerical data , Causality , Comorbidity , Female , Heart Failure/diagnostic imaging , Humans , Japan/epidemiology , Longitudinal Studies , Male , Myocardial Perfusion Imaging/methods , Myocardial Perfusion Imaging/statistics & numerical data , Myocardial Stunning/diagnostic imaging , Myocardial Stunning/mortality , Myocardial Stunning/prevention & control , Prevalence , Prognosis , Radiopharmaceuticals , Reproducibility of Results , Retrospective Studies , Sensitivity and Specificity , Survival Analysis , Tomography, Emission-Computed, Single-Photon/methods , Treatment Outcome , Ventricular Dysfunction, Left/prevention & controlABSTRACT
PURPOSE: Hibernating myocardium (HM) is associated with sudden cardiac death (SCD). Little is known about the electrophysiological properties of HM and the basis of its association with SCD. We aimed to electrophysiologically characterize HM in patients with ventricular tachycardia (VT). METHODS: Endocardial voltage mapping, metabolic 18FDG-positron emission tomography (PET) and perfusion 82Rb, 201Tl, or 99mTc scans were performed in 61 ischemic heart disease patients with VT. Hibernating areas were identified which was followed by three-dimensional PET reconstructions and integration with voltage maps to allow hybrid metabolic-electro-anatomic assessment of the arrhythmogenic substrate. RESULTS: Of 61 patients with ischemic heart disease and refractory VT, 7 were found to have hibernating myocardium (13%). A total of 303 voltage points were obtained within hibernating myocardium (8.2 points per 10 cm2) and displayed abnormal voltage in 48.5 and 78.3% of bipolar and unipolar recordings, respectively, with significant heterogeneity of bipolar (p < 0.0001) and unipolar voltage measurements (p = 0.0004). Hibernating areas in 6 of 7 patients contained all three categories of bipolar voltage-defined scar (<0.5 mV), border zone (0.5-1.5 mV), and normal myocardium (>1.5 mV). The characteristics of local electrograms were also assessed and found abnormal in most recordings (76.6, 10.2% fractionated, 5.3% isolated potentials). Exit sites of clinical VTs were determined in 6 patients, of which 3 were located within hibernating myocardium. CONCLUSIONS: Hibernating myocardium displays abnormal and heterogeneous electrical properties and seems to contribute to the substrate of VT. These observations may underlie the vulnerability to reentry and SCD in patients with hypoperfused yet viable myocardium.
Subject(s)
Body Surface Potential Mapping/methods , Fluorodeoxyglucose F18/pharmacokinetics , Heart Conduction System/physiopathology , Imaging, Three-Dimensional/methods , Myocardial Stunning/physiopathology , Tachycardia, Ventricular/physiopathology , Aged , Female , Heart Conduction System/diagnostic imaging , Humans , Male , Myocardial Stunning/complications , Myocardial Stunning/diagnostic imaging , Positron-Emission Tomography/methods , Reproducibility of Results , Sensitivity and Specificity , Tachycardia, Ventricular/complications , Tachycardia, Ventricular/diagnostic imagingABSTRACT
OBJECTIVE: The aim of the present study was to evaluate the presence and degree of spontaneous echo contrast (SEC) in the left atrium and of left atrial appendage (LAA) contractility before and after cardioversion (CV) in patients with recent-onset atrial fibrillation (AF). METHODS: Our study included 56 patients divided into two groups: group 1, comprising 32 clinically stable patients who were admitted to the Emergency Department with less than or equal to 48 h duration AF, and who underwent transoesophageal echocardiography (TEE)-guided CV; and the control group (group 2), comprising 24 patients admitted to the Cardiological Department for elective TEE-guided CV of greater than 48 h AF. All patients underwent repeat TEE within 1 h after successful CV. RESULTS: Patients with recent-onset AF (group 1) showed no thrombogenic milieu at baseline without any evidence of atrial stunning after successful CV. SEC mean grade (0-3 grading) was 0.09±0.3 versus 0.12±0.4 after CV (P=0.98), and LAA flow velocity was 60.7±19.4 versus 56.7±20.5 cm/s after CV (P=0.07). Group 2 patients showed a significantly higher degree of SEC compared with those in group 1 (0.09±0.3 vs. 0.66±0.7, P=0.0093) and significantly lower LAA flow velocities (60.7±19.4 vs. 32.5±12.4, P<0.0001), with significant worsening after successful CV (SEC degree: 0.66±0.9 vs. 1.37±0.9, P=0.0093; LAA flow velocity: 32.5±12.4 vs. 20.4±12.7 cm/s, P<0.0001). CONCLUSION: The absence of thrombogenic milieu and of left atrial stunning after CV in patients with recent-onset AF favours early CV without anticoagulation, at least in patients with a low thromboembolic risk profile. These patients could be discharged earlier from urgent care.
Subject(s)
Atrial Fibrillation/therapy , Electric Countershock , Heart Atria , Myocardial Stunning/etiology , Stroke/etiology , Thromboembolism/etiology , Echocardiography , Electric Countershock/adverse effects , Female , Heart Atria/diagnostic imaging , Heart Atria/physiopathology , Humans , Male , Middle Aged , Myocardial Stunning/diagnostic imaging , Risk Factors , Thromboembolism/epidemiologyABSTRACT
BACKGROUND: Early recognition of viable myocardium after acute myocardial infarction (AMI) is of clinical relevance, since affected segments have the potential of functional recovery. Delayed contrast-enhanced magnetic resonance imaging (DCE-CMR) has been validated extensively for the detection of viable myocardium. An alternative parameter for detecting viability is the perfusable tissue index (PTI), derived using [15O]H2O positron emission tomography (PET), which is inversely related to the extent of myocardial scar (non-perfusable tissue). The aim of the present study was to investigate the predictive value of PTI on recovery of LV function as compared to DCE-CMR in patients with AMI, after successful percutaneous coronary intervention (PCI). METHODS: Thirty-eight patients with ST elevation myocardial infarction (STEMI) successfully treated by PCI were prospectively recruited. Subjects were examined 1 week and 3 months (mean follow-up time: 97 ± 10 days) after AMI using [15O]H2O PET and DCE-CMR to assess PTI, regional function and scar. Viability was defined as recovery of systolic wall thickening ≥3.0 mm at follow-up by use of CMR. A total of 588 segments were available for serial analysis. RESULTS: At baseline, 180 segments were dysfunctional and exhibited DCE. Seventy-three (41%) of these dysfunctional segments showed full recovery during follow-up (viable), whereas 107 (59%) segments remained dysfunctional (nonviable). Baseline PTI of viable segments was 0.94 ± 0.09 and was significantly higher compared to nonviable segments (0.80 ± 0.13, P < .001). The optimal cut-off value for PTI was ≥0.85 with a sensitivity of 85% and specificity of 72%, and an area under the curve (AUC) of 0.82. In comparison, a cut-off value of <32% for the extent of DCE resulted in a sensitivity of 72% and a specificity of 69%, and an AUC of 0.75 (AUC PTI vs DCE P = .14). CONCLUSION: Assessment of myocardial viability shortly after reperfused AMI is feasible using PET. PET-derived PTI yields a good predictive value for the recovery of LV function in PCI-treated STEMI patients, in excellent agreement with DCE-CMR.
Subject(s)
Magnetic Resonance Imaging, Cine/methods , Myocardial Perfusion Imaging/methods , Myocardial Stunning/diagnostic imaging , Myocardial Stunning/etiology , Positron-Emission Tomography/methods , ST Elevation Myocardial Infarction/complications , ST Elevation Myocardial Infarction/diagnostic imaging , Contrast Media , Early Diagnosis , Feasibility Studies , Female , Humans , Male , Middle Aged , Oxygen Radioisotopes , Radiopharmaceuticals , Reproducibility of Results , Sensitivity and Specificity , WaterABSTRACT
PURPOSE: To develop a three-dimensional, free-breathing, late gadolinium enhancement (3D FB-LGE) cardiovascular magnetic resonance (CMR) technique, and to compare it with clinically used two-dimensional breath-hold LGE (2D BH-LGE). METHODS: The proposed 3D FB-LGE method consisted of inversion preparation, inversion delay, fat saturation, outer volume suppression, one-dimensional projection navigators, and a segmented stack of spirals acquisition. The 3D FB-LGE and 2D BH-LGE scans were performed on 29 cardiac patients. Qualitative analysis and quantitative analysis (in patients with scar) were performed. RESULTS: No significant differences were noted between the 3D FB-LGE and 2D BH-LGE data sets in terms of overall image quality score (2D: 4.69 ± 0.60 versus 3D: 4.55 ± 0.51, P = 0.46) and image artifact score (2D: 1.10 ± 0.31 versus 3D: 1.17 ± 0.38; P = 0.63). The average difference in fractional scar volume between the 3D and 2D methods was 1.9% (n = 5). Acquisition time was significantly shorter for the 3D FB-LGE over 2D BH-LGE by a factor of 2.83 ± 0.77 (P < 0.0001). CONCLUSIONS: The 3D FB-LGE is a viable option for patients, particularly in acute settings or in patients who are unable to comply with breath-hold instructions. Magn Reson Med 77:1533-1543, 2017. © 2016 International Society for Magnetic Resonance in Medicine.
Subject(s)
Image Enhancement/methods , Imaging, Three-Dimensional/methods , Magnetic Resonance Imaging, Cine/methods , Meglumine/analogs & derivatives , Myocardial Stunning/diagnostic imaging , Myocardial Stunning/pathology , Organometallic Compounds/administration & dosage , Algorithms , Contrast Media/administration & dosage , Female , Humans , Image Interpretation, Computer-Assisted/methods , Male , Meglumine/administration & dosage , Middle Aged , Reproducibility of Results , Respiratory Mechanics , Sensitivity and Specificity , Signal Processing, Computer-AssistedABSTRACT
PURPOSE: To investigate the presence of viable myocardium in mice with acute myocardial infarction (MI) using a molecular targeted probe. MATERIALS AND METHODS: Super paramagnetic iron oxide (SPIO) nanoparticles and tenascin-C antibody were conjugated as an MRI probe. Fifteen mice with infarction were injected with SPIO-anti-tenascin-C (3 days [d], 5d, 7d after infarction; n = 5 for each group). Another five mice with infarction (5d, n = 5) were injected with SPIO for comparison. In vivo MR (7 Tesla, fast low-angle shot multi-slice T2* sequence) was performed for tracing. Histological analysis was used to compare surviving cardiomyocytes with signal changes on MR. RESULTS: The mRNA expression of tenascin-C increased directly after MI and peaked at the fifth day (5d 24.29 ± 1.41 versus 3d 10.63 ± 0.72, 7d 6.56 ± 0.12; P < 0.01). T2 relaxation rate of synthesized SPIO-anti-tenascin-C was r2 = 338 mM-1 s-1 . After MR, the signal changes (contrast-to-noise ratio) of the research group were 3d 6.51 ± 1.13 versus 5d 14.06 ± 3.19 versus 7d 5.02 ± 2.65, P < 0.05. The MR signal showed a small decrease in the contrast group on 5d (research group 14.06 ± 3.19 versus contrast group 1.75 ± 0.59, P < 0.05). CONCLUSION: Tenascin-C was expressed by surviving cardiomyocytes within the infarcted region. MR imaging with SPIO-anti-tenascin-C might be used to evaluate myocardial viability of MI patients before therapy. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 4 J. MAGN. RESON. IMAGING 2017;45:1668-1674.
Subject(s)
Magnetic Resonance Imaging/methods , Molecular Imaging/methods , Myocardial Infarction/diagnostic imaging , Myocardial Infarction/metabolism , Myocardial Stunning/diagnostic imaging , Myocardial Stunning/metabolism , Tenascin/metabolism , Animals , Antibodies, Monoclonal/pharmacokinetics , Biomarkers/metabolism , Contrast Media/pharmacokinetics , Dextrans/pharmacokinetics , Female , Magnetite Nanoparticles , Mice , Mice, Inbred ICR , Myocardial Infarction/complications , Myocardial Stunning/etiology , Reproducibility of Results , Sensitivity and SpecificityABSTRACT
PURPOSE: To assess the diagnostic value of three-dimensional late enhancement (3D-LGE) for the detection of myocardial necrosis in a routine clinical setting. 3D-LGE has been proposed as a novel magnetic resonance (MR) technique for the accurate detection of myocardial scar in both the ventricles and atria. Its performance in clinical practice has been poorly examined. MATERIALS AND METHODS: Fifty-seven patients referred for cardiac MR examination including scar imaging were prospectively enrolled. Gadolinium enhanced single breathhold 3D T1-weighted gradient-echo inversion recovery sequence and a conventional 2D-LGE sequence were performed using a 1.5 Tesla clinical MR imaging system. The presence, pattern and transmurality of LGE, diagnostic accuracy and level of diagnostic confidence as well as image quality (median quality, mean LGE signal intensity, sharpness, virtual scan time) were graded on a 4-point scale. RESULTS: Interpretable images were obtained in 52/57 2D-LGE and in 47/57 3D high-resolution exams. LGE was detected in 10 patients with ischemic pattern, 9 with nonischemic pattern, while it was absent in 28, resulting in a total of 47 complete datasets. The detection of global and segmental LGE as well as its transmural extent were similar for both techniques (P = 0.65, P = 0.305, and P = 0.15, respectively). Image quality (median quality, LGE/ myocardial and LGE/ blood pool sharpness) was similar for both techniques (P = 0.740, P = 0.34, and P = 1.00, respectively), but LGE signal intensity was higher with 2D (P = 0.020). CONCLUSION: 3D-LGE diagnostic and quality scores were comparable to 2D-LGE in a routine clinical setting. Further technical refinement is required for 3D LGE to offer a reliable alternative for high quality scar imaging. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. MAGN. RESON. IMAGING 2017;45:1675-1683.
Subject(s)
Algorithms , Contrast Media/administration & dosage , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Myocardial Ischemia/diagnostic imaging , Myocardial Stunning/diagnostic imaging , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Image Enhancement/methods , Male , Middle Aged , Myocardial Ischemia/complications , Myocardial Ischemia/pathology , Myocardial Stunning/etiology , Myocardial Stunning/pathology , Reproducibility of Results , Sensitivity and Specificity , Young AdultABSTRACT
Abstract Background: Atrial fibrillation (AF) is the most common arrhythmia seen in adults. Atrial stunning is defined as the temporary mechanical dysfunction of the atrial appendage developing after AF has returned to sinus rhythm (SR). Objectives: We aimed to evaluate atrial contractile functions by strain and strain rate in patients with AF, following pharmacological and electrical cardioversion and to compare it with conventional methods. Methods: This study included 41 patients with persistent AF and 35 age-matched control cases with SR. All the AF patients included in the study had transthoracic and transesophageal echocardiography performed before and after. Septum (SEPsSR), left atrium (LAsSR) and right atrium peak systolic strain rate (RAsSR) were defined as the maximum negative value during atrial contraction and septum (SEPε), left atrium (LAε) and right atrium peak systolic strain (RAε) was defined as the percentage of change. Parameters of two groups were compared. Results: In the AF group, 1st hour and 24th hour LAε, RAε, SEPε, LAsSR, RAsSR, SEPsSR found to be significantly lower than in the control group (LAε: 2.61%±0.13, 3.06%±0.19 vs 6.45%±0.27, p<0.0001; RAε: 4.03%±0.38, 4.50%±0.47 vs 10.12%±0.64, p<0.0001; SEPε: 3.0%±0.22, 3.19%±0.15 vs 6.23%±0.49, p<0.0001; LAsSR: 0.61±0.04s-1, 0.75±0.04s- 1 vs 1.35±0.04s-1, p<0.0001; RAsSR: 1.13±0.06s-1, 1.23±0.07s-1 vs 2.10±0.08s- 1, p<0.0001; SEPsSR: 0.76±0.04s- 1, 0.78±0.04s- 1 vs 1.42±0.06 s- 1, p<0.0001). Conclusion: Atrial strain and strain rate parameters are superior to conventional echocardiographic parameters for the evaluation of atrial stunning in AF cases where SR has been achieved.
Resumo Fundamento: A fibrilação atrial (FA) é a arritmia mais comum em adultos. Define-se atordoamento atrial como a disfunção mecânica temporária do apêndice atrial que se desenvolve depois de reversão da FA ao ritmo sinusal (RS). Objetivos: Avaliar as funções atriais contráteis através de strain atrial e strain rate em pacientes com FA, após cardioversão farmacológica e elétrica, assim como compará-los com os métodos convencionais. Métodos: Este estudo incluiu 41 pacientes com FA persistente e 35 controles com RS e pareados por idade. Todos os pacientes com FA incluídos neste estudo foram submetidos a ecocardiografia transtorácica e transesofágica antes e após. Strain rates de pico sistólico do septo (SEPsSR), do átrio esquerdo (LAsSR) e do átrio direito (RAsSR) foram definidas como o máximo valor negativo durante contração atrial. Strains de pico sistólico do septo (SEPε), do átrio esquerdo (LAε) e do átrio direito (RAε) foram definidas como porcentagem de mudança. Resultados: No grupo com FA, os parâmetros LAε, RAε, SEPε, LAsSR, RAsSR e SEPsSR da 1a hora e da 24a hora foram significativamente mais baixos que no grupo controle (LAε: 2,61%±0,13; 3,06%±0,19 vs 6,45%±0,27; p<0,0001; RAε: 4,03%±0,38; 4,50%±0,47 vs 10,12%±0,64; p<0,0001; SEPε: 3,0%±0,22; 3,19%±0,15 vs 6,23%±0,49; p<0,0001; LAsSR: 0,61±0,04s-1; 0,75±0,04s-1 vs 1,35±0,04s-1; p<0,0001; RAsSR: 1,13±0,06s-1; 1,23±0,07s-1 vs 2,10±0,08s-1; p<0,0001; SEPsSR: 0,76±0,04s-1; 0,78±0,04s-1 vs 1,42±0,06 s-1; p<0,0001). Conclusão: Os parâmetros strain atrial e strain rate são superiores aos parâmetros ecocardiográficos convencionais para avaliar atordoamento atrial em pacientes com FA que reverteram ao RS.