Impact of age, sex, and indexation method on MR left ventricular reference values in the Framingham Heart Study offspring cohort.

PURPOSE: To determine normative values for left ventricular (LV) volumes, mass, concentricity, and ejection fraction (EF) and investigate associations between sex, age, and body size with LV parameters in community-dwelling adults. MATERIALS AND METHODS: In all, 1794 Framingham Heart Study Offspring cohort members underwent LV short-axis oriented, contiguous multislice cine steady-state free precession MR of the left ventricle; from these a healthy referent group (n = 852, 61 ± 9 years, 40% men) free of clinical cardiac disease and hypertension (SBP < 140, DBP < 90 mmHg, never used antihypertensive medication ≥30 years prior to scanning) was identified. Referent participants were stratified by sex and age group (≤55, 56-65, >65 years); LV parameters were indexed to measures of body size. RESULTS: Men have greater LV volumes and mass than women both before and after indexation to height, powers of height, and body surface area (P < 0.01 all), but indexation to fat-free mass yielded greater LV volume and mass in women. In both sexes, LV volumes and mass decrease with advancing age, although indexation attenuates this association. LVEF is greater in women than men (68 ± 5% vs. 66 ± 5%, P < 0.01) and increases with age in both sexes (P < 0.05). CONCLUSION: Among nonhypertensive adults free of cardiac disease, men have greater LV volumes and mass with sex differences generally persisting after indexation to body size. LV volumes and mass tend to decrease with greater age in both sexes. Female sex and advanced age were both associated with greater LVEF. J. Magn. Reson. Imaging 2015;41:1038-1045. © 2014 Wiley Periodicals, Inc.

Relationship between central and peripheral atherosclerosis and left ventricular dysfunction in a community population.

We aimed to determine the relationships between resting left ventricular (LV) wall motion abnormalities (WMAs), aortic plaque, and peripheral artery disease (PAD) in a community cohort. A total of 1726 Framingham Heart Study Offspring Cohort participants (806 males, 65 ± 9 years) underwent cardiovascular magnetic resonance with quantification of aortic plaque volume and assessment of regional left ventricular systolic function. Claudication, lower extremity revascularization, and ankle-brachial index (ABI) were recorded at the most contemporaneous examination visit. WMAs were associated with greater aortic plaque burden, decreased ABI, and claudication in age- and sex-adjusted analyses (all p < 0.001), which were not significant after adjustment for cardiovascular risk factors. In age- and sex-adjusted analyses, both the presence (p < 0.001) and volume of aortic plaque were associated with decreased ABI (p < 0.001). After multivariable adjustment, an ABI ≤ 0.9 or prior revascularization was associated with a threefold odds of aortic plaque (p = 0.0083). Plaque volume significantly increased with decreasing ABI in multivariable-adjusted analyses (p < 0.0001). In this free-living population, associations of WMAs with aortic plaque burden and clinical measures of PAD were attenuated after adjustment for coronary heart disease risk factors. Aortic plaque volume and ABI remained strongly negatively correlated after multivariable adjustment. Our findings suggest that the association between coronary heart disease and non-coronary atherosclerosis is explained by cardiovascular risk factors. Aortic atherosclerosis and PAD remain strongly associated after multivariable adjustment, suggesting shared mechanisms beyond those captured by traditional risk factors.

Cardiac Magnetic Resonance Versus Single-Photon Emission Computed Tomography for Detecting Coronary Artery Disease and Myocardial Ischemia: Comparison with Coronary Angiography.

BACKGROUND: This study aimed to compare the diagnostic accuracy of stress single-photon emission computed tomography (SPECT) and stress cardiac magnetic resonance (CMR) for the assessment of coronary artery disease (CAD) in the same patients, using coronary angiography as the reference standard. METHODS: Thirty patients with known or suspected CAD who were referred for exercise SPECT myocardial perfusion imaging (MPI) for the evaluation of myocardial ischemia underwent stress CMR MPI and computed tomography coronary angiography (CTCA) or selective coronary angiography (SCA). The data from the two stress modalities were compared against the data from angiography. RESULTS: In our study population, 30% of the recruited subjects had significant CAD. The CMR sensitivity for the detection of significant CAD and/or myocardial ischemia was 89% and specificity was 76%. For SPECT, the corresponding sensitivity was 78% and specificity was 52%. The negative predictive value was 92% for CMR and 83% for SPECT. The receiver-operating characteristic (ROC) analysis evaluating the presence of significant CAD, CMR (area under the curve (AUC) 0.78) outperformed SPECT (AUC 0.59) (p < 0.01). The ROC analysis evaluating the presence of myocardial ischemia was also in favor of CMR (AUC 0.82) versus SPECT (AUC 0.67) (p < 0.01). CONCLUSIONS: CMR has high diagnostic accuracy for the detection of CAD and stress-induced ischemia and appears to outperform SPECT. CMR may thus be the preferred noninvasive imaging modality to assess patients with known or suspected CAD.

Saw-tooth cardiomyopathy.

We present an unusual case of cardiomyopathy in a two month old male infant with a grade-I systolic murmur. Echocardiographic examination disclosed left ventricular (LV), dysplasia with saw-tooth like inwards myocardial projections extending from the lateral walls towards the LV cavity. There was mild LV systolic dysfunction with apical hypokinesia. Cardiovascular magnetic resonance demonstrated in detail these cross bridging muscular projections originating from the inferior interventricular septum and lateral LV wall, along with areas of hypokinesis at the LV septum and apex in a noncoronary distribution, without any late gadolinium enhancement. We have termed this condition saw-tooth cardiomyopathy because of the very characteristic appearance.

Fatal cardiac arrest due to an unusual fibroma of the pulmonary valve.

Fibroma, the second most common tumor in childhood, usually is a large solitary mass involving the ventricular septum or the left and rarely the right free ventricular wall. An unusual case of a 5.2-year-old boy with a large mass originating from the pulmonary valve is reported. The patient presented for evaluation of a murmur. Echocardiography and cardiac magnetic resonance imaging showed a large tumor extending from the distal right ventricular outflow tract through the pulmonary valve and into the main pulmonary artery causing moderate obstruction. The patient had a fatal cardiac arrest while awaiting surgery. The postmortem examination proved the tumor to be a fibroma.

The clockwise rotation of myocardial fiber orientation from epicardial to endocardial surface in left ventricular free wall in a post-mortem human heart.

Following fixation and MRI imaging a post-mortem human heart was sliced at the sagittal plane. Each anatomical section was then cut into smaller segments and each one was objected to classical histology process. The resulting microscopy slides were digitalized with a scanner. The histological section reconstruction was achieved using Adobe Photoshop CS2(R). Using specific software, called FiberCad, the user can define and draw (with the assistance of optical microscope) those fibers that are parallel and those fibers that are vertical to the slides plane. To better align the histological 3D reconstruction, the software is equipped with an option that allows the user to make best possible fit between histological and MRI slices. We present the consequent sagittal sections of LV free wall (from epicardial to endocardial surface), whereby the clockwise rotation of the mean orientation of the fibers that are on the plane of sectioning is clearly evident. We present a post mortem analysis of the complete LV free wall of a human heart.

One heart, two bodies: a simulation study of body surface potential differences between donor and recipient of heart transplantation.

In cardiac transplantation has been recognized some "abnormalities" in recipient ECG. We investigated the influence of heart geometrical position within the chest cavity as well as somatometric parameters on body surface torso potentials. Two control patients with different Body Mass Index (BMI) were undergone a chest MRI scan. Using specific software we created two tetrahedral meshes that could be applied in our study. A post-mortem human heart was undergone a MRI scan and we also created its tetrahedral mesh. Using second software we extracted the heart mesh of control's torsos and we replaced them with the mesh of the post-mortem heart. The last program also assessed the influence of heart (re)positioning within the thorax, on the body surface potentials. The Finite Elements Method (FEM) was used to solve the forward electrocardiographic problem for both torsos, under the assumption that all the ventricular myocardium of the one post-mortem heart was excited. FEM was also applied in simulating Body Surface Potential Mapping (BSPM) on the first thorax torso for nine different heart positions. For BSPM, FEM has been applied on Poison equation. The results show higher BSPM in patient with lower BMI and significant changes in BSPM when heart was rotated round its long axis. Conversely, the heart shifts (long x- or y- axis) didn't cause significant changes on simulated BSPM.

Coronary magnetic resonance imaging.

This article highlights the technical challenges and general imaging strategies for coronary MRI. This is followed by a review of the clinical results for the assessment of anomalous CAD, coronary artery aneurysms, native vessel integrity, and coronary artery bypass graft disease using the more commonly applied MRI methods. It concludes with a brief discussion of the advantages/disadvantages and clinical results comparing coronary MRI with multidetector CT (MDCT) coronary angiography.

Coronary magnetic resonance imaging.

This article highlights the technical challenges and general imaging strategies for coronary MRI. This is followed by a review of the clinical results for the assessment of anomalous CAD, coronary artery aneurysms, native vessel integrity, and coronary artery bypass graft disease using the more commonly applied MRI methods. It concludes with a brief discussion of the advantages/disadvantages and clinical results comparing coronary MRI with multidetector CT (MDCT) coronary angiography.

Statins decrease perioperative cardiac complications in patients undergoing noncardiac vascular surgery: the Statins for Risk Reduction in Surgery (StaRRS) study.

OBJECTIVES: We sought to assess whether statins may decrease cardiac complications in patients undergoing noncardiac vascular surgery. BACKGROUND: Cardiovascular complications account for considerable morbidity in patients undergoing noncardiac surgery. Statins decrease cardiac morbidity and mortality in patients with coronary disease, and the beneficial treatment effect is seen early, before any measurable increase in coronary artery diameter. METHODS: A retrospective study recorded patient characteristics, past medical history, and admission medications on all patients undergoing carotid endarterectomy, aortic surgery, or lower extremity revascularization over a two-year period (January 1999 to December 2000) at a tertiary referral center. Recorded perioperative complication outcomes included death, myocardial infarction, ischemia, congestive heart failure, and ventricular tachyarrhythmias occurring during the index hospitalization. Univariate and multivariate logistic regressions identified predictors of perioperative cardiac complications and medications that might confer a protective effect. RESULTS: Complications occurred in 157 of 1,163 eligible hospitalizations and were significantly fewer in patients receiving statins (9.9%) than in those not receiving statins (16.5%, p = 0.001). The difference was mostly accounted by myocardial ischemia and congestive heart failure. After adjusting for other significant predictors of perioperative complications (age, gender, type of surgery, emergent surgery, left ventricular dysfunction, and diabetes mellitus), statins still conferred a highly significant protective effect (odds ratio 0.52, p = 0.001). The protective effect was similar across diverse patient subgroups and persisted after accounting for the likelihood of patients to have hypercholesterolemia by considering their propensity to use statins. CONCLUSIONS: Use of statins was highly protective against perioperative cardiac complications in patients undergoing vascular surgery in this retrospective study.

Thymic Cyst Popping Up in a Patient With Congenital Heart Disease.

The unusual case of a thymic cyst emerging and rapidly expanding, mimicking hence a right atrial aneurysm in an asymptomatic patient with congenital heart disease is presented.

Diagnostic performance of coronary magnetic resonance angiography as compared against conventional X-ray angiography: a meta-analysis.

OBJECTIVES: This study was designed to define the current role of coronary magnetic resonance angiography (CMRA) for the diagnosis of coronary artery disease (CAD). BACKGROUND: Coronary magnetic resonance angiography has been proposed as a promising noninvasive method for diagnosis of CAD, but individual studies evaluating its clinical value have been of limited sample size. METHODS: We identified all studies (MEDLINE and EMBASE) that evaluated CAD by both CMRA and conventional angiography in >/=10 subjects during the period 1991 to January 2004. We recorded true and false positive and true and false negative CMRA assessments for detection of CAD using X-ray angiography as the reference standard. Analysis was done at segment, vessel, and subject level. RESULTS: We analyzed 39 studies (41 separate comparisons). Across 25 studies (27 comparisons) with data on 4,620 segments (993 subjects), sensitivity and specificity for detection of CAD were 73% and 86%, respectively. Vessel-level analyses (16 studies, 2,041 vessels) showed sensitivity 75% and specificity 85%. Subject-level analyses (13 studies, 607 subjects) showed sensitivity 88% and specificity 56%. At the segment level, sensitivity was 69% to 79% for all but the left circumflex (61%) coronary artery; specificity was 82% to 91%. There was considerable between-study heterogeneity, but weighted summary receiver-operating characteristic curves agreed with these estimates. There were no major differences between subgroups based on technical or population characteristics, year of publication, reported blinding, or sample size. CONCLUSIONS: In evaluable segments of the native coronary arteries, CMRA has moderately high sensitivity for detecting significant proximal stenoses and may have value for exclusion of significant multivessel CAD in selected subjects considered for diagnostic catheterization.

Electrocardiogram-gated single-photon emission computed tomography versus cardiac magnetic resonance imaging for the assessment of left ventricular volumes and ejection fraction: a meta-analysis.

OBJECTIVES: The purpose of this study was to evaluate the accuracy of electrocardiogram (ECG)-gated single-photon emission computed tomography (SPECT) for assessment of left ventricular (LV) end-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) compared with the gold standard of cardiac magnetic resonance imaging (MRI). BACKGROUND: Several comparisons of ECG-gated SPECT with cardiac MRI have been performed for evaluation of LV volumes and EF, but each has considered few subjects, thus leaving uncertainty about the frequency of discrepancies between the two methods. METHODS: We performed a meta-analysis of data on 164 subjects from nine studies comparing ECG-gated SPECT versus cardiac MRI. Data were pooled in correlation and regression analyses relating ECG-gated SPECT and cardiac MRI measurements. The frequency of discrepancies of at least 30 ml in EDV, 20 ml in ESV and 5% or 10% in EF and concordance for EF < or =40% versus >40% were determined. RESULTS: There was an overall excellent correlation between ECG-gated SPECT and cardiac MRI for EDV (r = 0.89), ESV (r = 0.92) and EF (r = 0.87). However, rates of discrepancies for individual subjects were considerable (37% [95% confidence interval [CI], 26% to 50%] for at least 30 ml in EDV; 35% [95% CI, 23% to 49%] for at least 20 ml in ESV; 52% [95% CI, 37% to 63%] for at least 5% in EF; and 23% [95% CI, 11% to 42%] for at least 10% in EF). The misclassification rate for the 40% EF cutoff was 11%. CONCLUSIONS: Electrocardiogram-gated SPECT measurements of EDV, ESV and EF show high correlation with cardiac MRI measurements, but substantial errors may occur in individual patients. Electrocardiogram-gated SPECT offers useful functional information, but cardiac MRI should be used when accurate measurement is required.

Effect of raloxifene on aortic elasticity in healthy postmenopausal women.

BACKGROUND: The effect of raloxifene on aortic elasticity in healthy postmenopausal women is unknown. The purpose of the present study was to examine the effect of raloxifene on aortic elasticity and cardiovascular structure and function in healthy postmenopausal women. METHODS: A randomized, crossover, double-blind, placebo-controlled clinical trial was performed. Fourteen healthy postmenopausal women received treatment with raloxifene 60 mg daily and matching placebo for 8 weeks with an 8-week washout period in between the 2 treatment periods. Cardiovascular magnetic resonance imaging was used to assess ascending thoracic and abdominal aortic elasticity and cardiovascular structure and function (left ventricular volumes, ejection fraction, and mass and mitral annular displacement) before and at the end of each treatment period. RESULTS: Administration of raloxifene had no significant effect on either heart rate or systemic blood pressure. Raloxifene treatment was associated with a small decrease of the ascending aorta wall thickness (pretreatment 2.4 +/- 0.3 vs posttreatment 2.2 +/- 0.2 mm, P = .01). Consequently, there was an increase in the Young's elastic modulus after raloxifene treatment at the ascending thoracic aorta but not the abdominal aorta. There were no significant differences in aortic compliance or any cardiac indexes after raloxifene treatment. CONCLUSIONS: Raloxifene administration in healthy postmenopausal women over an 8-week period may decrease the aortic wall thickness but has no significant effects on aortic compliance or cardiac structure and function.

Prone SPECT myocardial perfusion imaging is associated with less cardiac drift during the acquisition duration than imaging in the supine position.

BACKGROUND AND AIM: Cardiac cranial drift, a slow vertical upward displacement seen during the acquisition of myocardial single photon emission tomography (SPECT), is a source of image artefacts that may lead to erroneous interpretation. Changes in breathing pattern and depth throughout image acquisition are believed to cause cardiac cranial drift. As the physiology of respiration probably differs with postural changes, we hypothesized that cardiac drift may be different for supine vs. prone acquisitions. Our aim was to assess the magnitude of cardiac displacement for prone and supine SPECT acquisitions in patients undergoing stress myocardial perfusion imaging. METHODS: We enrolled prospectively 15 subjects undergoing exercise myocardial perfusion imaging. Subjects had post-stress images acquired in both the prone and supine positions. Motion was assessed in the horizontal (x) and vertical (y) axes for both camera heads at all 64 projections at which images were obtained. Pixel displacement (number of pixels from the baseline of zero) in either the cranial/caudal or left/right direction was quantified using the automated camera motion correction algorithm. RESULTS: Supine imaging was associated with more cranial drift than prone imaging (1.20+/-0.40 pixels vs. 0.92+/-0.24 pixels, P<0.05). There was no significant difference in cardiac displacement in the horizontal axis (1.03+/-0.5 pixels vs. 1.12+/-0.22 pixels, P=NS). CONCLUSIONS: Prone imaging is associated with less cardiac cranial drift than imaging in the supine position, suggesting that the former is associated with a more constant and reliable diaphragmatic breathing pattern. Acquisitions in the prone position may thus be associated with fewer motion artefacts than supine acquisitions for cardiac SPECT imaging.

Usefulness of electrocardiographic-gated stress technetium-99m sestamibi single-photon emission computed tomography to differentiate ischemic from nonischemic cardiomyopathy.

The noninvasive differentiation between ischemic and nonischemic cardiomyopathy is frequently difficult. We examined the clinical value of stress electrocardiographic gated (ECG-gated) single-photon emission computed tomography (SPECT) to identify ischemic cardiomyopathy and detect coronary artery disease (CAD) in 164 patients without known CAD, ejection fraction < or =40% by ECG-gated SPECT, and subsequent coronary angiography. Summed stress, rest, and difference scores were measured from the SPECT studies, and regional wall motion variance was calculated from the ECG-gated images. Sensitivity and 95% confidence intervals for the diagnosis of ischemic cardiomyopathy and for detection of any CAD (>50% diameter stenosis) were estimated using previously defined cutoffs for summed stress score and regional wall motion variance. For the diagnosis of ischemic cardiomyopathy, sensitivity of stress SPECT (summed stress score >8) was 87% (95% confidence interval [CI] 78 to 95), with a specificity of 63% (95% CI 60 to 82). The addition of wall motion information (summed stress score >8 or regional wall motion variance >0.114) increased sensitivity to 88% (95% CI 80 to 96) and decreased specificity to 45% (95% CI 35 to 55). If reversibility was also taken into account (summed stress score >8, regional wall motion variance >0.114, or summed difference score >0), sensitivity further increased to 94% (95% CI 88 to 100) and specificity decreased to 32% (95% CI 23 to 41). For detection of any CAD, the combined approach using stress perfusion, reversibility, and region of wall motion had a sensitivity of 94% (95% CI 89 to 99) and a specificity of 45% (95% CI 35 to 57). Therefore, ECG-gated SPECT is very sensitive for detection of ischemic cardiomyopathy and CAD among patients with moderate to severe systolic dysfunction.

Comparison of aortic elasticity determined by cardiovascular magnetic resonance imaging in obese versus lean adults.

The vascular properties of large vessels in the obese have not been adequately studied. We used cardiovascular magnetic resonance imaging to quantify the cross-sectional area and elastic properties of the ascending thoracic and abdominal aorta in 21 clinically healthy obese young adult men and 25 men who were age-matched lean controls. Obese subjects had greater maximal cross-sectional area of the ascending thoracic aorta (984 +/- 252 vs 786 +/- 109 mm(2), p <0.01) and of the abdominal aorta (415 +/- 71 vs 374 +/- 51 mm(2), p <0.05). When indexed for height the differences persisted, but when indexed for body surface area, a significant difference between groups was found only for the maximal abdominal aortic cross-sectional area. The obese subjects also had decreased abdominal aortic elasticity, characterized by 24% lower compliance (0.0017 +/- 0.0004 vs 0.0021 +/- 0.0005 mm(2)/kPa/mm, p <0.01), 22% higher stiffness index beta (6.0 +/- 1.5 vs 4.9 +/- 0.7, p <0.005), and 41% greater pressure-strain elastic modulus (72 +/- 25 vs 51 +/- 9, p <0.005). At the ascending thoracic aorta, only the pressure-strain elastic modulus was different between obese and lean subjects (85 +/- 42 vs 65 +/- 26 kPa, respectively; p <0.05), corresponding to a 31% difference-but arterial compliance and stiffness index were not significantly different between groups. In clinically healthy young adult obese men, obesity is associated with increased cross-sectional aortic area and decreased aortic elasticity.

ECG-gated 99mTc single-photon emission CT for assessment of right ventricular structure and function: is the information provided similar to echocardiography?

STUDY OBJECTIVE: (99m)Tc single-photon emission CT (SPECT) and ECG-gated SPECT can visualize well the right ventricle (RV) in most patients, but their utility for assessment of the RV has not been formally evaluated. We examined whether (99m)Tc SPECT/ECG-gated SPECT provide similar information to transthoracic two-dimensional Doppler echocardiography (2D-ECHO) regarding RV cavity size, wall thickness, and systolic function. DESIGN: Retrospective analysis. SETTING: A major university teaching hospital. PATIENTS: A consecutive series of 194 patients with good quality stress SPECT and 2D-ECHO studies performed within 1 day of each other and no significant interim cardiac events. MEASUREMENTS AND RESULTS: RV size and function were visually assessed by SPECT/ECG-gated SPECT and 2D-ECHO. RV wall thickness was visually assessed by SPECT and measured in mm in end-diastole by 2D-ECHO. Of 142 patients with normal RV cavity size by SPECT, 134 patients (94%) had normal RV cavity size by 2D-ECHO. However, of 52 patients with RV dilation by SPECT, only 9 patients (17%) had RV dilation by 2D-ECHO. A perfusion abnormality in the right coronary artery territory was significantly associated with RV dilation by SPECT (p < 0.005) and 2D-ECHO (p < 0.05). Among 150 patients with ECG-gated SPECT, only 2 patients had abnormal RV systolic function, as compared with 18 patients by 2D-ECHO. RV wall thickness measurements by SPECT and 2D-ECHO did not correlate. CONCLUSIONS: For normal interpretations regarding RV cavity size, wall thickness, and systolic function, there is good agreement between (99m)Tc stress SPECT/ECG-gated SPECT and 2D-ECHO. However, there is poor overall agreement between gated SPECT/ECG-gated SPECT and 2D-ECHO regarding the presence of RV dilation, hypertrophy, and systolic dysfunction.