Circ Cardiovasc Imaging. 2012; 5(3):283-285

Kawel N, Nacif M, Arai AE, Gomes AS, Hundley WG, Johnson C, Prince MR, Stacey RB, Lima JA, Bluemke DA

OBJECTIVES: A high degree of non-compacted (trabeculated) myocardium in relationship to compact myocardium (T/M ratio >2.3) has been associated with a diagnosis of left ventricular non-compaction (LVNC). The purpose of this study was to determine the normal range of the T/M ratio in a large population-based study and to examine the relationship to demographic and clinical parameters.

METHODS: The thickness of trabeculation and the compact myocardium were measured in eight LV regions on long axis cardiac magnetic resonance (CMR) steady-state free precession cine images in 1000 participants (551 women; 68.1±8.9 years) of the Multi-Ethnic Study of Atherosclerosis cohort.

RESULTS: Of 323 participants without cardiac disease or hypertension and with all regions evaluable 140 (43%) had a T/M ratio >2.3 in at least one region; in 20/323 (6%), T/M>2.3 was present in more than two regions. Multivariable linear regression model revealed no association of age, gender, ethnicity, height and weight with maximum T/M ratio in participants without cardiac disease or hypertension (p>0.05). In the entire cohort (n=1000) LVEF (β=-0.02/%; p=0.015), LVEDV (β=0.01/ml; p=<0.0001) and LVESV (β=0.01/ml; p<0.001) were associated with maximum T/M ratio in adjusted models while there was no association with hypertension or myocardial infarction (p>0.05). At the apical level T/M ratios were significantly lower when obtained on short- compared to long-axis images (p=0.017).

CONCLUSIONS: A ratio of trabeculated to compact myocardium of more than 2.3 is common in a large population based cohort. These results suggest reevaluation of the current CMR criteria for LVNC may be necessary.

PMID: 22499849

Eur Radiol. 2012; 22(6):1303-1309

Buss SJ, Schulz F, Wolf D, Hosch W, Galuschky C, Schummers G, Giannitsis E, Kauczor HU, Zugck C, Becker R, Hardt SE, Katus HA, Korosoglou G

OBJECTIVES: We investigated whether cardiac computed tomography (CCT) can determine intraventricular dyssynchrony in comparison to real-time three-dimensional echocardiography (RT3DE) in patients who are considered for cardiac resynchronisation therapy (CRT).

METHODS: 35 patients considered for CRT were examined. Left ventricular (LV) dyssynchrony was quantified by calculating the standard deviation index (SDI) of 17 myocardial LV segments by RT3DE and ECG-gated contrast-enhanced 64-slice dual-source CCT. For both analyses the same software algorithm (4D LV-Analysis) was used.

RESULTS: Close correlations were observed for end-systolic volume, end-diastolic volume and LV ejection fraction between the two techniques (r = 0.94, r = 0.92 and r = 0.95, respectively, P < 0.001 for all). For the global dyssynchrony index SDI, a high correlation was found between RT3DE and CCT (r = 0.84, P < 0.001), which further increased after exclusion of segments with poor image quality by echocardiography (r = 0.90, P < 0.001). The required time for quantitative analysis was significantly shorter (162 ± 22 s vs. 608 ± 112 s per patient, P < 0.001) and reproducibility was significantly higher for CCT compared with RT3DE (interobserver variability of 4.5 ± 3.1% vs. 7.9 ± 6.1%, P < 0.05).

CONCLUSIONS: Quantitative assessment of LV dyssynchrony is feasible by CCT. Owing to its higher reproducibility and faster analysis time compared with RT3DE, this technique may represent a valuable alternative for dyssynchrony assessment. Key Points : • Quantitative assessment of left ventricular dyssynchrony is feasible by cardiac computed tomography (CCT). • This technique has been compared with real-timethree-dimensional echocardiography (RT3DE). • Reproducibility is significantly higher for CCT compared with RT3DE. • Time spent for analysis is significantly shorter for CCT. • Computed tomography may represent a valuable alternative to ultrasound for dyssynchrony assessment.

PMID: 22270144

J Am Coll Cardiol. 2012; 59(21):1849-1860

Raymond J. Gibbons, Philip A. Araoz, and Thomas C. Gerber

N/A.

PMID:

J Am Coll Cardiol. 2012; 59(21):1897-1907

Johannes Greupner, Elke Zimmermann, Andrea Grohmann, Hans-Peter Dübel, Till Althoff, Adrian C. Borges, Wolfgang Rutsch, Peter Schlattmann, Bernd Hamm, and Marc Dewey

OBJECTIVES: This study was designed to compare the accuracy of 64-row contrast computed tomography (CT), invasive cineventriculography (CVG), 2-dimensional echocardiography (2D Echo), and 3-dimensional echocardiography (3D Echo) for left ventricular (LV) function assessment with magnetic resonance imaging (MRI). Cardiac function is an important determinant of therapy and is a major predictor for long-term survival in patients with coronary artery disease. A number of methods are available for assessment of function, but there are limited data on the comparison between these multiple methods in the same patients.

METHODS: A total of 36 patients prospectively underwent 64-row CT, CVG, 2D Echo, 3D Echo, and MRI (as the reference standard). Global and regional LV wall motion and ejection fraction (EF) were measured. In addition, assessment of interobserver agreement was performed.

RESULTS: For the global EF, Bland-Altman analysis showed significantly higher agreement between CT and MRI (p < 0.005, 95% confidence interval: ±14.2%) than for CVG (±20.2%) and 3D Echo (±21.2%). Only CVG (59.5 ± 13.9%, p = 0.03) significantly overestimated EF in comparison with MRI (55.6 ± 16.0%). CT showed significantly better agreement for stroke volume than 2D Echo, 3D Echo, and CVG. In comparison with MRI, CVG—but not CT—significantly overestimated the end-diastolic volume (p < 0.001), whereas 2D Echo and 3D Echo significantly underestimated the EDV (p < 0.05). There was no significant difference in diagnostic accuracy (range: 76% to 88%) for regional LV function assessment between the 4 methods when compared with MRI. Interobserver agreement for EF showed high intraclass correlation for 64-row CT, MRI, 2D Echo, and 3D Echo (intraclass correlation coefficient >0.8), whereas agreement was lower for CVG (intraclass correlation coefficient = 0.58).

CONCLUSIONS: 64-row CT may be more accurate than CVG, 2D Echo, and 3D Echo in comparison with MRI as the reference standard for assessment of global LV function.

PMID:

Circ Cardiovasc Imaging. 2012; 5(2):171-174

Peng Gao, Lorne Gula, Raymond Yee, Andrew D. Krahn, Allan Skanes, Peter Leong-Sit, George J. Klein, John Stirrat, Nowell Fine, Luljeta Pallaveshi, Gerald Wisenberg, Terry R. Thompson, Frank Prato, Maria Drangova, and James A. White

OBJECTIVES: Scar signal quantification using Late Gadolinium Enhancement Cardiac Magnetic Resonance (LGE-CMR) identifies patients at higher risk of future events, both in ischemic cardiomyopathy (ICM) and non-ischemic dilated cardiomyopathy (DCM). However, the ability of scar signal burden to predict events in such patient groups at the time of referral for implantable cardioverter-defibrillator (ICD) has not been well explored. This study evaluates the predictive utility of multiple scar quantification measures in ICM and DCM patients being referred for ICD.

METHODS: 124 consecutive patients referred for ICD therapy (59 with ICM and 65 with DCM) underwent a standardized LGE-CMR protocol with blinded, multi-threshold scar signal quantification and, for those with ICM, peri-infarct signal quantification. Patients were prospectively followed for the primary combined outcome of appropriate ICD therapy, survived cardiac arrest or sudden cardiac death.

RESULTS: At a mean follow-up of 632 ± 262 days, 18 patients (15%) had suffered the primary outcome. Total scar was significantly higher among those suffering a primary outcome, a relationship maintained within each cardiomyopathy cohorts (p<0.01 for all comparisons). Total scar was the strongest independent predictor of the primary outcome and demonstrated a negative predictive value of 86%. In the ICM sub-cohort peri-infarct signal showed only a non-significant trend towards elevation among those having a primary endpoint.

CONCLUSIONS: Myocardial scar quantification by LGE-CMR predicts arrhythmic events in patients being evaluated for ICD eligibility irrespective of cardiomyopathy etiology.

PMID:

J Am Coll Cardiol. 2012; 59(20):1799-1808

Jennifer L. Dorosz, Dennis C. Lezotte, David A. Weitzenkamp, Larry A. Allen, Ernesto E. Salcedo

OBJECTIVES: The primary aim of this systematic review is to objectively evaluate the test performance characteristics of three-dimensional echocardiography (3DE) in measuring left ventricular (LV) volumes and ejection fraction (EF). Despite its growing use in clinical laboratories, the accuracy of 3DE has not been studied on a large scale. It is unclear if this technology offers an advantage over traditional two-dimensional (2D) methods.

METHODS: We searched for studies that compared LV volumes and EF measured by 3DE and cardiac magnetic resonance (CMR) imaging. A subset of those also compared standard 2D methods with CMR. We used meta-analyses to determine the overall bias and limits of agreement of LV end-diastolic volume (EDV), end-systolic volume (ESV), and EF measured by 3DE and 2D echocardiography (2DE).

RESULTS: Twenty-three studies (1,638 echocardiograms) were included. The pooled biases ± 2 SDs for 3DE were –19.1 ± 34.2 ml, –10.1 ± 29.7 ml, and – 0.6 ± 11.8% for EDV, ESV, and EF, respectively. Nine studies also included data from 2DE, where the pooled biases were –48.2 ± 55.9 ml, –27.7 ± 45.7 ml, and 0.1 ± 13.9% for EDV, ESV, and EF, respectively. In this subset, the difference in bias between 3DE and 2D volumes was statistically significant (p = 0.01 for both EDV and ESV). The difference in variance was statistically significant (p < 0.001) for all 3 measurements.

CONCLUSIONS: Three-dimensional echocardiography underestimates volumes and has wide limits of agreement, but compared with traditional 2D methods in these carefully performed studies, 3DE is more accurate for volumes and more precise in all 3 measurements.

PMID:

Int J Cardiovasc Imaging. 2012; 28(3):514-517

Kälsch H, Lehmann N, Möhlenkamp S, Hammer C, Mahabadi AA, Moebus S, Schmermund A, Stang A, Bauer M, Jöckel KH, Erbel R; On behalf of the Investigator Group of the Heinz Nixdorf Recall Study

OBJECTIVES: Thoracic aortic calcification (TAC) and coronary artery calcium (CAC) have been proposed for risk assessment of coronary artery and cardiovascular disease events. The aim of this analysis is to assess the prevalence of TAC and to determine its relationship with cardiovascular risk factors and CAC in a general unselected population.

METHODS: TAC was measured from electron beam computed tomography scans and quantified by Agatston-Score in 4,025 participants aged 45-75 years (mean age 59.4 ± 7.8 years, 53 % female) from the Heinz Nixdorf Recall Study. Multivariable generalized linear regression was used to evaluate relationships between TAC and cardiovascular risk factors and CAC.

RESULTS: Overall 2,538/4,025 (63.1 %) participants revealed TAC. Prevalence of TAC was greater in men than in women (65.2 vs. 61.7 %, p = 0.009). TAC was most strongly associated with age, systolic blood pressure, smoking and high levels of LDL-cholesterol. Prevalence of CAC was significantly higher in participants with TAC than without (74.0 vs. 57.6 %, p < 0.0001) demonstrating an increased risk of having CAC in the presence of TAC (prevalence ratio (PR) 1.29 [95 % CI: 1.22-1.35], p < 0.0001, PR adjusted for risk factors 1.14 [1.09-1.20], p < 0.0001).

CONCLUSIONS: In general population, TAC has high prevalence and largely shares cardiovascular risk factors with CAD while being independently associated with present CAC.

PMID: 22527262

J Am Coll Cardiol. 2012; 59(17):1539-1548

Dweck MR, Chow MW, Joshi NV, Williams MC, Jones C, Fletcher AM, Richardson H, White A, McKillop G, van Beek EJ, Boon NA, Rudd JH, Newby DE

OBJECTIVES: With combined positron emission tomography and computed tomography (CT), we investigated coronary arterialuptake of 18F-sodium fluoride (18F-NaF) and 18F-fluorodeoxyglucose (18F-FDG) as markers of active plaque calcification and inflammation, respectively. The noninvasive assessment of coronary artery plaque biology would be a major advance particularly in the identification of vulnerable plaques, which are associated with specific pathological characteristics, including micro-calcification and inflammation.

METHODS: We prospectively recruited 119 volunteers (72 ± 8 years of age, 68% men) with and without aortic valve disease and measured their coronary calcium score and 18F-NaF and 18F-FDG uptake. Patients with a calcium score of 0 were used as control subjects and compared with those with calcific atherosclerosis (calcium score >0).

RESULTS: Inter-observer repeatability of coronary 18F-NaF uptake measurements (maximum tissue/background ratio) was excellent (intra-class coefficient 0.99). Activity was higher in patients with coronary atherosclerosis (n = 106) versus control subjects (1.64 ± 0.49 vs. 1.23 ± 0.24; p = 0.003) and correlated with the calcium score (r = 0.652, p < 0.001), although 40% of those with scores >1,000 displayed normal uptake. Patients with increased coronary 18F-NaF activity (n = 40) had higher rates of prior cardiovascular events (p = 0.016) and angina (p = 0.023) and higher Framingham risk scores (p = 0.011). Quantification ofcoronary 18F-FDG uptake was hampered by myocardial activity and was not increased in patients with atherosclerosis versus control subjects (p = 0.498).

CONCLUSIONS: 18F-NaF is a promising new approach for the assessment of coronary artery plaque biology. Prospective studies with clinical outcomes are now needed to assess whether coronary 18F-NaF uptake represents a novel marker of plaque vulnerability, recent plaque rupture, and future cardiovascular risk. (An Observational PET/CT Study Examining the Role of Active Valvular Calcification and Inflammation in Patients With Aortic Stenosis; NCT01358513).

PMID: 22516444

J Am Coll Cardiol. 2012; 59(19):1719-1728

Caroline Jaarsma, Tim Leiner, Sebastiaan C. Bekkers, Harry J. Crijns, Joachim E. Wildberger, Eike Nagel, Patricia J. Nelemans, and Simon Schalla

OBJECTIVES: This study aimed to determine the diagnostic accuracy of the 3 most commonly used noninvasive myocardial perfusion imaging modalities, single-photon emission computed tomography (SPECT), cardiac magnetic resonance (CMR), and positron emission tomography (PET) perfusion imaging for the diagnosis of obstructive coronary artery disease (CAD). Additionally, the effect of test and study characteristics was explored. Accurate detection of obstructive CAD is important for effective therapy. Noninvasive myocardial perfusion imaging is increasingly being applied to gauge the severity of CAD.

METHODS: Studies published between 1990 and 2010 identified by PubMed search and citation tracking were examined. A study was included if a perfusion imaging modality was used as a diagnostic test for the detection of obstructive CAD and coronary angiography as the reference standard (50% diameter stenosis).

RESULTS: Of the 3,635 citations, 166 articles (n = 17,901) met the inclusion criteria: 114 SPECT, 37 CMR, and 15 PET articles. There were not enough publications on other perfusion techniques such as perfusion echocardiography and computed tomography to include these modalities into the study. The patient-based analysis per imaging modality demonstrated a pooled sensitivity of 88% (95% confidence interval [CI]: 88% to 89%), 89% (95% CI: 88% to 91%), and 84% (95% CI: 81% to 87%) for SPECT, CMR, and PET, respectively; with a pooled specificity of 61% (95% CI: 59% to 62%), 76% (95% CI: 73% to 78%), and 81% (95% CI: 74% to 87%). This resulted in a pooled diagnostic odds ratio (DOR) of 15.31 (95% CI: 12.66 to 18.52; I ² 63.6%), 26.42 (95% CI: 17.69 to 39.47; I ² 58.3%), and 36.47 (95% CI: 21.48 to 61.92; I ² 0%). Most of the evaluated test and study characteristics did not affect the ranking of diagnostic performances.

CONCLUSIONS: SPECT, CMR, and PET all yielded a high sensitivity, while a broad range of specificity was observed. SPECT is widely available and most extensively validated; PET achieved the highest diagnostic performance; CMR may provide an alternative without ionizing radiation and a similar diagnostic accuracy as PET. We suggest that referring physicians consider these findings in the context of local expertise and infrastructure.

PMID:

Circulation: Cardiovascular Imaging. 2012; 5(2):187-193

Nadine Kawel, Marcelo Nacif, Andrew E. Arai, Antoinette S. Gomes, W. Gregory Hundley, Craig Johnson, Martin R. Prince, R. Brandon Stacey, João A.C. Lima and David A. Bluemke

OBJECTIVES: A high degree of non-compacted (trabeculated) myocardium in relationship to compact myocardium (T/M ratio >2.3) has been associated with a diagnosis of left ventricular non-compaction (LVNC). The purpose of this study was to determine the normal range of the T/M ratio in a large population-based study and to examine the relationship to demographic and clinical parameters.

METHODS: The thickness of trabeculation and the compact myocardium were measured in eight LV regions on long axis cardiac magnetic resonance (CMR) steady-state free precession cine images in 1000 participants (551 women; 68.1±8.9 years) of the Multi-Ethnic Study of Atherosclerosis cohort.

RESULTS: Of 323 participants without cardiac disease or hypertension and with all regions evaluable 140 (43%) had a T/M ratio >2.3 in at least one region; in 20/323 (6%), T/M>2.3 was present in more than two regions. Multivariable linear regression model revealed no association of age, gender, ethnicity, height and weight with maximum T/M ratio in participants without cardiac disease or hypertension (p>0.05). In the entire cohort (n=1000) LVEF (β=-0.02/%; p=0.015), LVEDV (β=0.01/ml; p=<0.0001) and LVESV (β=0.01/ml; p<0.001) were associated with maximum T/M ratio in adjusted models while there was no association with hypertension or myocardial infarction (p>0.05). At the apical level T/M ratios were significantly lower when obtained on short- compared to long-axis images (p=0.017).

CONCLUSIONS: A ratio of trabeculated to compact myocardium of more than 2.3 is common in a large population based cohort. These results suggest reevaluation of the current CMR criteria for LVNC may be necessary.

PMID: 22499849