Disagreement between splenic switch-off and myocardial T1-mapping after caffeine intake.

Caffeine is an adenosine receptor antagonist and a possible cause of inadequate stress perfusion. Splenic switch-off (SSO) and splenic rest-stress T1-mapping have been proposed as indicators of stress adequacy during perfusion cardiac magnetic resonance (CMR). We compared myocardial rest-stress T1-mapping with SSO and splenic rest-stress T1-mapping in patients with and without recent coffee intake.

Accurate late gadolinium enhancement prediction by early T1- based quantitative synthetic mapping.

Objectives: Early synthetic gadolinium enhancement (ESGE) imaging from post-contrast T1 mapping after adenosine stress-perfusion cardiac magnetic resonance (CMR) was compared to conventional late gadolinium enhancement (LGE) imaging for assessing myocardial scar.

Methods: Two hundred fourteen consecutive patients suspected of myocardial ischaemia were referred for stress-perfusion CMR. Myocardial infarct volume was quantified on a per-subsegment basis in both synthetic (2-3 min post-gadolinium) and conventional (9 min post-gadolinium) images by two independent observers.

Automated regional wall motion abnormality detection by combining rest and stress cardiac MRI: correlation with contrast-enhanced MRI.

Purpose: To correlate an automated regional wall motion abnormality (RWMA) detection method based on combined rest and dobutamine-stress cardiac MRI with the assessment of myocardial infarction from contrast-enhanced MRI (CE-MRI), and to demonstrate that adding stress data improves the detection of scar segments compared with rest data alone.

Materials And Methods: An automated RWMA detection method was built based on a statistical model of normokinetic myocardium from 41 healthy volunteers. The method was adapted to detect changes in RWMA from rest to stress.

Infarct tissue heterogeneity assessed with contrast-enhanced MRI predicts spontaneous ventricular arrhythmia in patients with ischemic cardiomyopathy and implantable cardioverter-defibrillator.

Background: The relation between infarct tissue heterogeneity on contrast-enhanced MRI and the occurrence of spontaneous ventricular arrhythmia (or sudden cardiac death) is unknown. Therefore, the study purpose was to evaluate the predictive value of infarct tissue heterogeneity assessed with contrast-enhanced MRI on the occurrence of spontaneous ventricular arrhythmia with subsequent implantable cardioverter-defibrillator (ICD) therapy (as surrogate of sudden cardiac death) in patients with previous myocardial infarction.

Methods And Results: Ninety-one patients (age, 65+/-11 years) with previous myocardial infarction scheduled for ICD implantation underwent cine MRI to evaluate left ventricular function and volumes and contrast-enhanced MRI for characterization of scar tissue (infarct gray zone as measure of infarct tissue heterogeneity, infarct core, and total infarct size).

Automated detection of regional wall motion abnormalities based on a statistical model applied to multislice short-axis cardiac MR images.

In this paper, a statistical shape analysis method for myocardial contraction is presented that was built to detect and locate regional wall motion abnormalities (RWMA). For each slice level (base, middle, and apex), 44 short-axis magnetic resonance images were selected from healthy volunteers to train a statistical model of normal myocardial contraction using independent component analysis (ICA). A classification algorithm was constructed from the ICA components to automatically detect and localize abnormally contracting regions of the myocardium.

Agreement and disagreement between contrast-enhanced magnetic resonance imaging and nuclear imaging for assessment of myocardial viability.

Purpose: The purpose of this study was to compare contrast-enhanced MRI and nuclear imaging with (99m)Tc-tetrofosmin and (18)F-fluorodeoxyglucose ((18)F-FDG) single photon emission computed tomography (SPECT) for assessment of myocardial viability.

Methods: Included in the study were 60 patients with severe ischaemic left ventricular (LV) dysfunction who underwent contrast-enhanced MRI, (99m)Tc-tetrofosmin and (18)F-FDG SPECT. Myocardial segments were assigned a wall motion score from 0 (normokinesia) to 4 (dyskinesia) and a scar score from 0 (no scar) to 4 (76-100% transmural extent).

Effect of intramyocardial bone marrow cell injection on diastolic function in patients with chronic myocardial ischemia.

Purpose: To evaluate the effect of intramyocardial bone marrow cell injection on diastolic function in patients with chronic myocardial ischemia.

Materials And Methods: In 24 patients (19 male; 65 +/- 9 years) with refractory angina (Canadian Cardiovascular Society [CCS] class III-IV) 84.6 +/- 28.

Comparison of myocardial infarct size assessed with contrast-enhanced magnetic resonance imaging and left ventricular function and volumes to predict mortality in patients with healed myocardial infarction.

Currently, left ventricular (LV) ejection fraction (EF) and/or LV volumes are the established predictors of mortality in patients with coronary artery disease (CAD) and severe LV dysfunction. With contrast-enhanced magnetic resonance imaging (MRI), precise delineation of infarct size is now possible. The relative merits of LVEF/LV volumes and infarct size to predict long-term outcome are unknown.

Effect of total scar burden on contrast-enhanced magnetic resonance imaging on response to cardiac resynchronization therapy.

It was shown that improvement in left ventricular (LV) function and reverse remodeling after cardiac resynchronization therapy (CRT) were greater in patients with nonischemic cardiomyopathy than in those with ischemic cardiomyopathy. The aim of this study is to evaluate the influence of scar burden on response to CRT. We included 34 patients with ischemic cardiomyopathy (New York Heart Association class 3.

Assessment of right ventricular infarction with contrast-enhanced magnetic resonance imaging.

Objective: Evaluation of contrast-enhanced magnetic resonance imaging to assess right ventricular infarction in patients with acute inferior myocardial infarction.

Background: Contrast-enhanced magnetic resonance imaging has been used for assessing scar tissue after left ventricular infarction. The value of contrast-enhanced magnetic resonance imaging to assess right ventricular infarction is unknown and was evaluated.

Usefulness of intramyocardial injection of autologous bone marrow-derived mononuclear cells in patients with severe angina pectoris and stress-induced myocardial ischemia.

Bone marrow cell transplantation has been proposed as a novel therapeutic option for patients with coronary artery disease. This study investigated whether autologous bone marrow-derived mononuclear cell injection into the ischemic myocardium of patients with severe angina pectoris could safely reduce anginal symptoms, improve myocardial perfusion, and increase left ventricular (LV) function. In a total of 20 patients (63 +/- 10 years old; 16 men) with angina pectoris, myocardial segments with stress-induced ischemia as assessed by gated single-photon emission computed tomography were injected with 30 to 100 million mononuclear cells.

Effect of posterolateral scar tissue on clinical and echocardiographic improvement after cardiac resynchronization therapy.

Background: Currently, one third of patients treated with cardiac resynchronization therapy (CRT) do not respond. Nonresponse to CRT may be explained by the presence of scar tissue in the posterolateral left ventricular (LV) segments, which may result in ineffective LV pacing and inadequate LV resynchronization. In the present study, the relationship between transmural posterolateral scar tissue and response to CRT was evaluated.

Which parameters on magnetic resonance imaging determine Q waves on the electrocardiogram?

Studies have demonstrated that patients with Q-wave infarctions on the electrocardiogram (ECG) frequently have nontransmural scar formation, whereas non-Q-wave infarctions may have transmural scars. The precise pathophysiologic substrate that underlies Q waves remains unclear. Magnetic resonance imaging (MRI) is the preferred technique to evaluate patients who have infarction because information can be obtained on function, contractile reserve (viability), and scar tissue.

Quantification of myocardial infarct size and transmurality by contrast-enhanced magnetic resonance imaging in men.

Contrast-enhanced magnetic resonance (ce-MR) imaging allows precise delineation of infarct transmurality. An issue of debate is whether data analysis should be performed visually or quantitatively. Accordingly, a head-to-head comparison was performed between visual and quantitative analyses of infarct transmurality on ce-MR imaging.

Head-to-head comparison between contrast-enhanced magnetic resonance imaging and dobutamine magnetic resonance imaging in men with ischemic cardiomyopathy.

Contrast-enhanced magnetic resonance imaging (MRI) can predict functional recovery after revascularization. Segments with small, subendocardial scars have a large likelihood of recovery, and segments with transmural infarction have a small likelihood of recovery. Segments with an intermediate extent of infarction have an intermediate likelihood of recovery, and therefore, additional information is needed.

Three-dimensional navigator coronary MRA with the aid of a blood pool agent in pigs: improved image quality with inclusion of the contrast agent first-pass.

Purpose: To evaluate the effect of including the first-pass of a blood pool agent (BPA) on the image quality of three-dimensional navigator coronary MRA.

Materials And Methods: A pig model was used to perform: 1) T1 simulation of the BPA, based on actual blood samples, and 2) BPA-enhanced three-dimensional navigator coronary MRA, with or without inclusion of the first-pass of the BPA. The acquisitions with inclusion of the first-pass were timed with the use of a test bolus.