Circ Cardiovasc Imaging. 2012; 5(1):12-20

White JA, Fine NM, Gula L, Yee R, Skanes A, Klein G, Leong-Sit P, Warren H, Thompson T, Drangova M, Krahn A

OBJECTIVES: Sudden cardiac death (SCD) and sustained monomorphic ventricular tachycardia (SMVT) are frequently associated with prior or acute myocardial injury. Cardiovascular magnetic resonance (CMR) provides morphological, functional, and tissue characterization in a single setting. We sought to evaluate the diagnostic yield of CMR-based imaging versus non-CMR-based imaging in patients with resuscitated SCD or SMVT.

METHODS: Eighty-two patients with resuscitated SCD or SMVT underwent routine non-CMR imaging, followed by a CMR protocol with comprehensive tissue characterization. Clinical reports of non-CMR imaging studies were blindly adjudicated and used to assign each patient to 1 of 7 diagnostic categories. CMR imaging was blindly interpreted using a standardized algorithm used to assign a patient diagnosis category in a similar fashion. The diagnostic yield of CMR-based and non-CMR-based imaging, as well as the impact of the former on diagnosis reclassification, was established.

RESULTS: Relevant myocardial disease was identified in 51% of patients using non-CMR-based imaging and in 74% using CMR-based imaging (P=0.002). Forty-one patients (50%) were reassigned to a new or alternate diagnosis using CMR-based imaging, including 15 (18%) with unsuspected acute myocardial injury. Twenty patients (24%) had no abnormality by non-CMR imaging but showed clinically relevant myocardial disease by CMR imaging.

CONCLUSIONS: CMR-based imaging provides a robust diagnostic yield in patients presenting with resuscitated SCD or SMVT and incrementally identifies clinically unsuspected acute myocardial injury. When compared with non-CMR-based imaging, a new or alternate myocardial disease process may be identified in half of these patients.

PMID: 22038987

J Am Coll Cardiol. 2012; 59(5):462-474

Rory Hachamovitch, Benjamin Nutter, Mark A. Hlatky, Leslee J. Shaw, Michael L. Ridner, Sharmila Dorbala, Rob S.B. Beanlands, Benjamin J.W. Chow, Elizabeth Branscomb, Panithaya Chareonthaitawee, W. Guy Weigold, Szilard Voros, Suhny Abbara, Tsunehiro Yasuda, Jill E. Jacobs, John Lesser, Daniel S. Berman, Louise E.J. Thomson, Subha Raman, Gary V. Heller, Adam Schussheim, Richard Brunken, Kim A. Williams, Susan Farkas, Dominique Delbeke, Uwe J. Schoepf, Nathaniel Reichek, Stuart Rabinowitz, Steven R. Sigman, Randall Patterson, Carolyn R. Corn, Richard White, Ella Kazerooni, James Corbett, Sabahat Bokhari, Josef Machac, Erminia Guarneri, Salvador Borges-Neto, John W. Millstine, James Caldwell, James Arrighi, Udo Hoffmann, Matthew Budoff, Joao Lima, James R. Johnson, Barbara Johnson, Mariya Gaber, Julie A. Williams, Courtney Foster, Jon Hainer, Marcelo F. Di Carli SPARC Investigators

OBJECTIVES: This study examined short-term cardiac catheterization rates and medication changes after cardiac imaging. Noninvasive cardiac imaging is widely used in coronary artery disease, but its effects on subsequent patient management are unclear.

METHODS: We assessed the 90-day post-test rates of catheterization and medication changes in a prospective registry of 1,703 patients without a documented history of coronary artery disease and an intermediate to high likelihood of coronary artery disease undergoing cardiac single-photon emission computed tomography, positron emission tomography, or 64-slice coronary computed tomography angiography.

RESULTS: Baseline medication use was relatively infrequent. At 90 days, 9.6% of patients underwent catheterization. The rates of catheterization and medication changes increased in proportion to test abnormality findings. Among patients with the most severe test result findings, 38% to 61% were not referred to catheterization, 20% to 30% were not receiving aspirin, 35% to 44% were not receiving a beta-blocker, and 20% to 25% were not receiving a lipid-lowering agent at 90 days after the index test. Risk-adjusted analyses revealed that compared with stress single-photon emission computed tomography or positron emission tomography, changes in aspirin and lipid-lowering agent use was greater after computed tomography angiography, as was the 90-day catheterization referral rate in the setting of normal/nonobstructive and mildly abnormal test results.

CONCLUSIONS: Overall, noninvasive testing had only a modest impact on clinical management of patients referred for clinical testing. Although post-imaging use of cardiac catheterization and medical therapy increased in proportion to the degree of abnormality findings, the frequency of catheterization and medication change suggests possible undertreatment of higher risk patients. Patients were more likely to undergo cardiac catheterization after computed tomography angiography than after single-photon emission computed tomography or positron emission tomography after normal/nonobstructive and mildly abnormal study findings.

PMID:

Circ Cardiovasc Imaging. 2012; 5(1):147-154

Truong QA, Massaro JM, Rogers IS, Mahabadi AA, Kriegel MF, Fox CS, O'Donnell CJ, Hoffmann U

OBJECTIVES: Main pulmonary artery diameter (mPA) and ratio of mPA to ascending aorta diameter (ratio PA) derived from chest CT are commonly reported in clinical practice. We determined the age- and sex-specific distribution and normal reference values for mPA and ratio PA by CT in an asymptomatic community-based population.

METHODS: In 3171 men and women (mean age, 51±10 years; 51% men) from the Framingham Heart Study, a noncontrast, ECG-gated, 8-slice cardiac multidetector CT was performed. We measured the mPA and transverse axial diameter of the ascending aorta at the level of the bifurcation of the right pulmonary artery and calculated the ratio PA. We defined the healthy referent cohort (n=706) as those without obesity, hypertension, current and past smokers, chronic obstructive pulmonary disease, history of pulmonary embolism, diabetics, cardiovascular disease, and heart valve surgery.

RESULTS: The mean mPA diameter in the overall cohort was 25.1±2.8 mm and mean ratio PA was 0.77±0.09. The sex-specific 90th percentile cutoff value for mPA diameter was 28.9 mm in men and 26.9 mm in women and was associated with increase risk for self-reported dyspnea (adjusted odds ratio, 1.31; P=0.02). The 90th percentile cutoff value for ratio PA of the healthy referent group was 0.91, similar between sexes but decreased with increasing age (range, 0.82-0.94), though not associated with dyspnea.

CONCLUSIONS: For simplicity, we established 29 mm in men and 27 mm in women as sex-specific normative reference values for mPA and 0.9 for ratio PA.

PMID: 22178898

Circulation. 2012; 125(2):260-270

Galper BZ, Moran A, Coxson PG, Pletcher MJ, Heidenreich P, Lazar LD, Rodondi N, Wang YC, Goldman L

OBJECTIVES: Noninvasive stress testing might guide the use of aspirin and statins for primary prevention of coronary heart disease, but it is unclear if such a strategy would be cost effective.

METHODS: We compared the status quo, in which the current national use of aspirin and statins was simulated, with 3 other strategies: (1) full implementation of Adult Treatment Panel III guidelines, (2) a treat-all strategy in which all intermediate-risk persons received statins (men and women) and aspirin (men only), and (3) a test-and-treat strategy in which all persons with an intermediate risk of coronary heart disease underwent stress testing and those with a positive test were treated with high-intensity statins (men and women) and aspirin (men only). Healthcare costs, coronary heart disease events, and quality-adjusted life years from 2011 to 2040 were projected.

RESULTS: Under a variety of assumptions, the treat-all strategy was the most effective and least expensive strategy. Stress electrocardiography was more effective and less expensive than other test-and-treat strategies, but it was less expensive than treat all only if statin cost exceeded $3.16/pill or if testing increased adherence from75%. However, stress electrocardiography could be cost effective in persons initially nonadherent to the treat-all strategy if it raised their adherence to 5% and cost saving if it raised their adherence to 13%.

CONCLUSIONS: When generic high-potency statins are available, noninvasive cardiac stress testing to target preventive medications is not cost effective unless it substantially improves adherence.

PMID: 22144567

Radiographics. 2012; 32(1):9-32

Elena Pena, Carole Dennie, John Veinot, and Susana Hernandez Muniz

Pulmonary hypertension is defined as an abnormal elevation of pressure in pulmonary circulation, with a mean pulmonary arterial pressure higher than 25 mmHg, regardless of the underlying mechanism. The clinical classification system for pulmonary hypertension was updated at the fourth World Symposium on Pulmonary Hypertension in Dana Point, California, in 2008. In patients with suspected pulmonary hypertension, the diagnostic approach includes four stages: suspicion, detection, classification, and functional evaluation. It is crucial to understand the advantages and disadvantages of the different imaging tools available for the diagnostic work-up and follow-up of patients with pulmonary hypertension. Many conditions that cause pulmonary hypertension have suggestive findings at multidetector computed tomography or magnetic resonance imaging; some causes may be surgically treatable, whereas others may demonstrate adverse reactions to vasodilator therapies used during the course of treatment. Therefore, the radiologist plays an important role in evaluating patients with this disease.

PMID: 22236891

Circulation. 2012; 125(1):76-86

Dweck MR, Jones C, Joshi N, Fletcher AM, Richardson H, White A, Marsden M, Pessotto R, Clark JC, Wallace WA, Salter DM, McKillop G, van Beek EJ, Boon NA, Rudd JH, Newby DE

OBJECTIVES: The pathophysiology of aortic stenosis is incompletely understood and the relative contributions of valvular calcification and inflammation to disease progression are unknown.

METHODS: Patients with aortic sclerosis and mild, moderate and severe stenosis were prospectively compared to age and sex-matched control subjects. Aortic valve severity was determined by echocardiography. Calcification and inflammation in the aortic valve were assessed by sodium 18-fluoride (18F-NaF) and 18-fluorodeoxyglucose (18F-FDG) uptake using positron emission tomography. One hundred and twenty one subjects (20 controls; 20 aortic sclerosis; 25 mild, 33 moderate and 23 severe aortic stenosis) were administered both 18F-NaF and 18F-FDG.

RESULTS: Quantification of tracer uptake within the valve demonstrated excellent inter-observer repeatability with no fixed or proportional biases and limits of agreement of ±0.21 (18F-NaF) and ±0.13 (18F-FDG) for maximum tissue-to-background ratios (TBR). Activity of both tracers was higher in patients with aortic stenosis than control subjects (18F-NaF:2.87±0.82 vs 1.55±0.17; 18F-FDG: 1.58±0.21 vs 1.30±0.13; both P1.97) and 35% increased 18F-FDG (>1.63) uptake. A weak correlation between the activities of these tracers was observed (r(2)= 0.174, P

CONCLUSIONS: Positron emission tomography is a novel, feasible and repeatable approach to thee valuation of valvular calcification and inflammation in patients with aortic stenosis. The frequency and magnitude of increased tracer activity correlates with disease severity, and is strongest for 18F-NaF.

PMID: 22090163

Heart. 2011; 98(1):12

Ismail TF, Prasad SK, Pennell DJ

Cardiovascular magnetic resonance has revolutionised the diagnosis of cardiomyopathy, particularly through the use of late gadolinium enhancement imaging which provides the unique opportunity to assess myocardial fibrosis in vivo. More recently, the prognostic capability of cardiovascular magnetic resonance to predict outcomes has been assessed. Traditional risk markers do not at present adequately predict outcomes in either dilated cardiomyopathy or hypertrophic cardiomyopathy, which are the two most common causes of primary heart muscle disease. Many of these existing markers reflect underlying disease severity. Given the important role fibrosis is thought to play in the pathogenesis and sequelae of these cardiomyopathies, the presence and amount of fibrosis has been proposed as a potential novel risk factor for adverse events. This paper reviews the evidence for late gadolinium enhancement as a prognostic marker in dilated and hypertrophic cardiomyopathy and highlights the challenges ahead.

PMID: 22128204

Circ Cardiovasc Imaging. 2011; 4(6):597-600

Thavendiranathan P, Walls M, Giri S, Verhaert D, Rajagopalan S, Moore S, Simonetti OP, Raman SV

OBJECTIVES: T2-weighted cardiac magnetic resonance (CMR) is useful in diagnosing acute inflammatory myocardial diseases such as myocarditis and tako-tsubo cardiomyopathy (TTCM). We hypothesized that quantitative T2 mapping could better delineate myocardial involvement in these disorders vs. T2-weighted imaging.

METHODS: Thirty patients with suspected myocarditis or TTCM referred for CMR who met established diagnostic criteria underwent myocardial T2 mapping. T2 values were averaged in involved and remote myocardial segments, both defined by a reviewer blinded to T2 data.

RESULTS: In myocarditis, T2 was 65.2±3.2ms in the involved myocardium vs. 53.5±2.1 in remote myocardium (p0.05 for all). T2 maps provided diagnostic data even in patients with difficulty breath-holding. A T2 cutoff of 59ms identified areas of myocardial involvement with sensitivity and specificity of 94% and 97%, respectively. T2 mapping revealed regions of abnormal T2 beyond those identified by wall motion abnormalities or LGE-positivity. Conventional T2-weighted short tau inversion recovery (T2W-STIR) images were uninterpretable in 7 patients due to artifact and unremarkable in 2 who had elevated T2 values. T2-prepared steady state free precession (T2p-SSFP) images showed areas of signal hyperintensity in only17/30 patients.

CONCLUSIONS: Quantitative T2 mapping reliably identifies myocardial involvement in patients with myocarditis and TTCM. T2 mapping delineated greater extent of myocardial disease in both conditions compared to that identified by wall motion abnormalities, T2W-STIR, T2p-SSFP or LGE. Quantitative T2 mapping warrants consideration as a robust technique to identify myocardial injury in patients with acute myocarditis or TTCM.

PMID: 22038988

J Am Coll Cardiol. 2011; 58(22):2270-2278

Villines TC, Hulten EA, Shaw LJ, Goyal M, Dunning A, Achenbach S, Al-Mallah M, Berman DS, Budoff MJ, Cademartiri F, Callister TQ, Chang HJ, Cheng VY, Chinnaiyan K, Chow BJ, Delago A, Hadamitzky M, Hausleiter J, Kaufmann P, Lin FY, Maffei E, Raff GL, Min JK; CONFIRM Registry Investigators

OBJECTIVES: The purpose of this study was to describe the prevalence and severity of coronary artery disease (CAD) in relation to prognosis in symptomatic patients without coronary artery calcification (CAC) undergoing coronary computed tomography angiography (CCTA). The frequency and clinical relevance of CAD in patients without CAC are unclear.

METHODS: We identified 10,037 symptomatic patients without CAD who underwent concomitant CCTA and CAC scoring. CAD was assessed as

RESULTS: Mean age was 57 years, 56% were men, and 51% had a CAC score of 0. Among patients with a CAC score of 0, 84% had no CAD, 13% had nonobstructive stenosis, and 3.5% had ≥50% stenosis (1.4% had ≥70% stenosis) on CCTA. A CAC score >0 had a sensitivity, specificity, and negative and positive predictive values for stenosis ≥50% of 89%, 59%, 96%, and 29%, respectively. During a median of 2.1 years, there was no difference in mortality among patients with a CAC score of 0 irrespective of obstructive CAD. Among 8,907 patients with follow-up for the composite endpoint, 3.9% with a CAC score of 0 and ≥50% stenosis experienced an event (hazard ratio: 5.7; 95% confidence interval: 2.5 to 13.1; p < 0.001) compared with 0.8% of patients with a CAC score of 0 and no obstructive CAD. Receiver-operator characteristic curve analysis demonstrated that the CAC score did not add incremental prognostic information compared with CAD extent on CCTA for the composite endpoint (CCTA area under the curve = 0.825; CAC + CCTA area under the curve = 0.826; p = 0.84).

CONCLUSIONS: In symptomatic patients with a CAC score of 0, obstructive CAD is possible and is associated with increased cardiovascular events. CAC scoring did not add incremental prognostic information to CCTA.

PMID:

Circulation. 2011; 124(19):2049-2051

Grothoff M, Elpert C, Hoffmann J, Zachrau J, Lehmkuhl L, de Waha S, Desch S, Eitel I, Mende M, Thiele H, Gutberlet M

OBJECTIVES: Patients with right ventricular injury (RVI) complicating ST-elevation myocardial infarction (STEMI) suffer from impaired prognosis, but it is unclear which patients are at risk of developing RVI. Cardiac magnetic resonance (CMR) can identify these patients and might add important information on risk stratification, prognosis and treatment. Aims were to determine the predictors and the prognostic significance of RVI assessed by wall motion abnormalities, edema, myocardial-salvage-index (MSI) and delayed enhancement (DE) in acute reperfused STEMI.

METHODS: We studied 450 patients 1-4 days after primary angioplasty in STEMI. T2-weighted and DE CMR was used for visualizing edema and scar to calculate MSI. Cine-imaging was performed to assess wall motion abnormalities, which, in combination with edema, were considered diagnostic for RVI. Patients with RVI were compared to matched patients with isolated left ventricular (LV) infarction. The primary endpoint was the occurrence of a major adverse cardiac event (MACE): a composite of death, reinfarction and congestive heart failure after a median follow-up period of 20.9 months.

RESULTS: RVI was present in 69 patients and 41/69 showed myocardial necrosis. In a multivariable stepwise forward logistic regression analysis a high RV myocardial mass (Odds-Ratio 2.06, 95% Confidence-Interval 1.18-3.58, p=0.012) and a low TIMI-flow pre angioplasty (Odds-Ratio 0.50, 95% CI 0.32-0.76, p=0.011) were associated with RVI. Cox regression analysis revealed RVI as the most statistically significant predictor of time to MACE (Hazard-Ratio 3.36, 95% CI 1.99-5.66, p

CONCLUSIONS: RVI detected by CMR is a strong and independent predictor of clinical outcome after acute reperfused STEMI.

PMID: