Search

Objectives This study sought to identify predictors of major clinically important atrial fibrillation endpoints in hypertrophic cardiomyopathy. Background Atrial fibrillation (AF) is a common morbidity associated with hypertrophic cardiomyopathy (HCM). The HCMR (Hypertrophic Cardiomyopathy Registry) trial is a prospective natural history study of 2,755 patients with HCM with comprehensive phenotyping. Methods All patients received yearly telephone follow-up. Major AF endpoints were defined as requiring electrical cardioversion, catheter ablation, hospitalization for >24 h, or clinical decisions to accept permanent AF. Penalized regression via elastic-net methodology identified the most important predictors of major AF endpoints from 46 variables. This was applied to 10 datasets, and the variables were ranked. Predictors that appeared in all 10 sets were then used in a Cox model for competing risks and analyzed as time to first event. Results Data from 2,631 (95.5%) patients were available for analysis after exclusions. A total of 127 major AF endpoints events occurred in 96 patients over 33.3 ± 12.4 months. In the final model, age, body mass index (BMI), left atrial (LA) volume index, LA contractile percent (active contraction), moderate or severe mitral regurgitation (MR), and history of arrhythmia the most important. BMI, LA volume index, and LA contractile percent were age-dependent. Obesity was a stronger risk factor in younger patients. Increased LA volume, reduced LA contractile percent, and moderate or severe MR put middle-aged and older adult patients at increased risk. Conclusions The major predictors of major AF endpoints in HCM include older age, high BMI, moderate or severe MR, history of arrhythmia, increased LA volume, and reduced LA contractile percent. Prospective testing of a risk score based on these parameters may be warranted.

Aims Vitamin D deficiency is associated with cardiovascular events in chronic kidney disease (CKD) yet the impact of supplementation is controversial. Previous active vitamin D supplementation studies did not show improvement in cardiac structure or function but the effect of native vitamin D supplementation in CKD patients with low vitamin D levels is unknown. We have addressed this question via both a randomized double-blind prospective study and a meta-analysis of three randomized placebo-controlled studies. Methods and results We conducted a randomized double-blind, placebo-controlled trial of vitamin D supplementation in stable, non-diabetic, CKD three to four patients with circulating vitamin D Conclusion Vitamin D supplementation does not have beneficial effects on LV mass in CKD patients.

Background: Omega-3 fatty acids from fish oil have been associated with beneficial cardiovascular effects, but their role in modifying cardiac structures and tissue characteristics in patients who have had an acute myocardial infarction while receiving current guideline-based therapy remains unknown. Methods: In a multicenter, double-blind, placebo-controlled trial, participants presenting with an acute myocardial infarction were randomly assigned 1:1 to 6 months of high-dose omega-3 fatty acids (n=180) or placebo (n=178). Cardiac magnetic resonance imaging was used to assess cardiac structure and tissue characteristics at baseline and after study therapy. The primary study endpoint was change in left ventricular systolic volume index. Secondary endpoints included change in noninfarct myocardial fibrosis, left ventricular ejection fraction, and infarct size. Results: By intention-to-treat analysis, patients randomly assigned to omega-3 fatty acids experienced a significant reduction of left ventricular systolic volume index (–5.8%, P =0.017), and noninfarct myocardial fibrosis (–5.6%, P =0.026) in comparison with placebo. Per-protocol analysis revealed that those patients who achieved the highest quartile increase in red blood cell omega-3 index experienced a 13% reduction in left ventricular systolic volume index in comparison with the lowest quartile. In addition, patients in the omega-3 fatty acid arm underwent significant reductions in serum biomarkers of systemic and vascular inflammation and myocardial fibrosis. There were no adverse events associated with high-dose omega-3 fatty acid therapy. Conclusions: Treatment of patients with acute myocardial infarction with high-dose omega-3 fatty acids was associated with reduction of adverse left ventricular remodeling, noninfarct myocardial fibrosis, and serum biomarkers of systemic inflammation beyond current guideline-based standard of care. Clinical Trial Registration: URL: http://www.clinicaltrials.gov . Unique identifier: NCT00729430.

Supplemental Digital Content is available in the text., Background: The common intronic deletion, MYBPC3Δ25, detected in 4% to 8% of South Asian populations, is reported to be associated with cardiomyopathy, with ≈7-fold increased risk of disease in variant carriers. Here, we examine the contribution of MYBPC3Δ25 to hypertrophic cardiomyopathy (HCM) in a large patient cohort. Methods: Sequence data from 2 HCM cohorts (n=5393) was analyzed to determine MYBPC3Δ25 frequency and co-occurrence of pathogenic variants in HCM genes. Case-control and haplotype analyses were performed to compare variant frequencies and assess disease association. Analyses were also undertaken to investigate the pathogenicity of a candidate variant MYBPC3 c.1224-52G>A. Results: Our data suggest that the risk of HCM, previously attributed to MYBPC3Δ25, can be explained by enrichment of a derived haplotype, MYBPC3Δ25/−52, whereby a small subset of individuals bear both MYBPC3Δ25 and a rare pathogenic variant, MYBPC3 c.1224-52G>A. The intronic MYBPC3 c.1224-52G>A variant, which is not routinely evaluated by gene panel or exome sequencing, was detected in ≈1% of our HCM cohort. Conclusions: The MYBPC3 c.1224-52G>A variant explains the disease risk previously associated with MYBPC3Δ25 in the South Asian population and is one of the most frequent pathogenic variants in HCM in all populations; genotyping services should ensure coverage of this deep intronic mutation. Individuals carrying MYBPC3Δ25 alone are not at increased risk of HCM, and this variant should not be tested in isolation; this is important for the large majority of the 100 million individuals of South Asian ancestry who carry MYBPC3Δ25 and would previously have been declared at increased risk of HCM.

Atrial fibrillation (AF) is a common morbidity associated with hypertrophic cardiomyopathy (HCM). Prior studies have focused on AF incidence. In HCMR, we have focused on predictors of clinically significant AF episodes defined as; 1) requiring electrical cardioversion or catheter ablation 2)

Scar volume quantified by cardiovascular magnetic resonance (CMR) with late gadolinium enhancement (LGE) is a novel imaging biomarker for risk stratification in patients with hypertrophic cardiomyopathy (HCM) [(1)][1]. In current practice, scar quantification often relies on manual delineation of

Background— The screening of Icelandic patients clinically diagnosed with hypertrophic cardiomyopathy resulted in identification of 8 individuals from 2 families with X-linked Fabry disease (FD) caused by GLA (α-galactosidase A gene) mutations encoding p.D322E (family A) or p.I232T (family B). Methods and Results— Familial screening of at-risk relatives identified mutations in 16 family A members (8 men and 8 heterozygotes) and 25 family B members (10 men and 15 heterozygotes). Clinical assessments, α-galactosidase A (α-GalA) activities, glycosphingolipid substrate levels, and in vitro mutation expression were used to categorize p.D322E as a classic FD mutation and p.I232T as a later-onset FD mutation. In vitro expression revealed that p.D322E and p.I232T had α-GalA activities of 1.4% and 14.9% of the mean wild-type activity, respectively. Family A men had markedly decreased α-GalA activity and childhood-onset classic manifestations, except for angiokeratoma and cornea verticillata. Family B men had residual α-GalA activity and developed FD manifestations in adulthood. Despite these differences, all family A and family B men >30 years of age had left ventricular hypertrophy, which was mainly asymmetrical, and had similar late gadolinium enhancement patterns. Ischemic stroke and severe white matter lesions were more frequent among family A men, but neither family A nor family B men had overt renal disease. Family A and family B heterozygotes had less severe or no clinical manifestations. Conclusions— Men with classic or later-onset FD caused by GLA missense mutations developed prominent and similar cardiovascular disease at similar ages, despite markedly different α-GalA activities.

ObjectivesThis study sought to assess the impact of body mass index (BMI) on cardiac phenotypic and clinical course in a multicenter hypertrophic cardiomyopathy (HCM) cohort.BackgroundIt is unresolved whether clinical variables promoting left ventricular (LV) hypertrophy in the general population, such as obesity, may influence cardiac phenotypic and clinical course in patients with HCM.MethodsIn 275 adult HCM patients (age 48 ± 14 years; 70% male), we assessed the relation of BMI to LV mass, determined by cardiovascular magnetic resonance (CMR) and heart failure progression.ResultsAt multivariate analysis, BMI proved independently associated with the magnitude of hypertrophy: pre-obese and obese HCM patients (BMI 25 to 30 kg/m2 and >30 kg/m2, respectively) showed a 65% and 310% increased likelihood of an LV mass in the highest quartile (>120 g/m2), compared with normal weight patients (BMI 120 g/m2 were LV outflow obstruction (HR: 4.9; 95% CI: 2.4 to 9.8; p < 0.001), systemic hypertension (HR: 2.2; 95% CI: 1.1 to 4.5; p = 0.026), and male sex (HR: 2.1; 95% CI: 0.9 to 4.7; p = 0.083). During a median follow-up of 3.7 years (interquartile range: 2.5 to 5.3), obese patients showed an HR of 3.6 (95% CI: 1.2 to 10.7, p = 0.02) for developing New York Heart Association (NYHA) functional class III to IV symptoms compared to nonobese patients, independent of outflow obstruction. Noticeably, the proportion of patients in NYHA functional class III at the end of follow-up was 13% among obese patients, compared with 6% among those of normal weight (p = 0.03).ConclusionsIn HCM patients, extrinsic factors such as obesity are independently associated with increase in LV mass and may dictate progression of heart failure symptoms.

Background— The 2 most commonly affected genes in hypertrophic cardiomyopathy (HCM) are MYH7 (β-myosin heavy chain) and MYBPC3 (β-myosin-binding protein C). Phenotypic differences between patients with mutations in these 2 genes have been inconsistent. Scarce data exist on the genotype–phenotype association as assessed by tomographic imaging using cardiac magnetic resonance imaging. Methods and Results— Cardiac magnetic resonance imaging was performed on 358 consecutive genotyped hypertrophic cardiomyopathy probands at 5 tertiary hypertrophic cardiomyopathy centers. Genetic testing revealed a pathogenic mutation in 159 patients (44.4%). The most common genes identified were MYH7 (n=53) and MYBPC3 (n=75); 33.1% and 47% of genopositive patients, respectively. Phenotypic characteristics by cardiac magnetic resonance imaging of these 2 groups were similar, including left ventricular volumes, mass, maximal wall thickness, morphology, left atrial volume, and mitral valve leaflet lengths (all P =non-significant). The presence of late gadolinium enhancement (65% versus 64%; P =0.99) and the proportion of total left ventricular mass (%late gadolinium enhancement; 10.4±13.2% versus 8.5±8.5%; P =0.44) were also similar. Conclusions— This multicenter multinational study shows lack of phenotypic differences between MYH7- and MYBPC3-associated hypertrophic cardiomyopathy when assessed by cardiac magnetic resonance imaging. Postmutational mechanisms appear more relevant to thick-filament disease expression and outcome than the disease-causing variant per se.

Preparticipation screening of athletes with 12-lead electrocardiography has been promoted for the detection of asymptomatic cardiovascular disease, particularly hypertrophic cardiomyopathy (HC). Although false-positive electrocardiographic (ECG) results for HC are well recognized in athlete screening, expected false-negative rates are unknown. The aim of this study was to characterize the rate of false-negative ECG findings in a cohort of young asymptomatic patients with phenotypically expressed HC, defined by cardiovascular magnetic resonance, using the 2010 European Society of Cardiology recommended ECG criteria for the identification of suspected heart disease in trained athletes. Cardiac magnetic resonance studies and 12-lead electrocardiography were performed in 114 consecutive asymptomatic patients with HC aged ≤35 years (mean age 22 ± 8 years; 77% male patients). Electrocardiograms were analyzed to distinguish pathologic ECG patterns from alterations considered nonpathologic and physiologic consequences of athletic training. Among the 114 patients with HC, 103 (90%) demonstrated ≥1 pathologic ECG abnormality, while the remaining 11 patients (10%) had normal or nonpathologic ECG patterns and therefore defined a subgroup in whom ECG screening would not be expected to raise suspicion of heart disease (i.e., false-negative results). In this false-negative ECG results group, maximal left ventricular wall thickness was 17 ± 2 mm (range 15 to 21), compared to patients with pathologic ECG patterns, in whom maximal left ventricular wall thickness was 22 ± 5 mm (p = 0.003). In conclusion, a substantial minority of young asymptomatic patients with HC with phenotypically expressed left ventricular hypertrophy have nonpathologic ECG findings on the basis of the 2010 European Society of Cardiology guidelines. In principle, this high false-negative rate of 10% represents an important limitation in applying 12-lead electrocardiography to large, apparently healthy athletic populations for the detection of HC.

Background— In hypertrophic cardiomyopathy (HCM), the arrhythmic potential associated with a variety of left ventricular myocardial signal intensities evident on contrast-enhanced cardiovascular magnetic resonance with late gadolinium enhancement (LGE) is unresolved. Methods and Results— In 145 HCM patients (43±15 years old), visually identified areas of LGE in left ventricle were analyzed quantitatively for intermediate (≥4 but P =0.003 to P =0.02–0.003) than patients without these arrhythmias. In HCM patients with either nonsustained ventricular tachycardia, couplets, or premature ventricular contractions, the extent of intermediate LGE-SI exceeded that of high LGE-SI (17±7 versus 15±6 g, 16±10 versus 14±9 g, and 13±8 versus 12±7 g, respectively; P =0.01–0.04). In addition, the receiver operating characteristic area under the curve established intermediate LGE-SI as a better discriminator of patients with nonsustained ventricular tachycardia than was high LGE-SI, with 7 additional patients with this arrhythmia identified. Conclusions— In patients with HCM, intermediate LGE-SI is a better predictor of ventricular tachyarrhythmias (including nonsustained ventricular tachycardia, a risk factor for sudden death) than is high LGE-SI. Longitudinal studies in larger HCM cohorts are justified to define the independent prognostic impact of intermediate LGE-SI.

Introduction: In hypertrophic cardiomyopathy (HCM), there are significant variations in left ventricular (LV) wall thickness and fibrosis, which necessitates a volumetric coverage. Slice-interleaved T1 (STONE) mapping sequence allows for the assessment of native T1 time with complete coverage of LV myocardium. Hypothesis: We hypothesized that STONE sequence is useful for the assessment of regional native T1 time abnormality in HCM patients. Methods: Twenty-four septal HCM patients (56±16 years) and 10 healthy adult control subjects (57±15 years) were studied. Native T1 mapping was performed using STONE sequence which enables acquisition of 5 slices in the short-axis plane within a 90 sec free-breathing scan. We measured LV native T1 time and maximum LV wall thickness in each 16 segments from 3 slices (basal-, mid- and apical-slice) and evaluated the relationship between LV native T1 time and wall thickness. Late gadolinium enhanced (LGE) MRI was acquired to assess presence of myocardial enhancement. Results: In HCM patients, LV native T1 time was significantly elevated compared to healthy controls, regardless of presence or absence of LGE (mean native T1 time; LGE (+) segments (n=27), 1139±55 msec; LGE (-) segments (n=351), 1118±55 msec; healthy control (n=160),1065±35 msec; p Conclusions: In HCM, substantial number of segments without LGE showed elevated native T1 time, and native T1 time was correlated with LV wall thickness. Multi-slice T1 mapping by using STONE sequence could be advantageous to overcome limited cardiac coverage of conventional single-slice T1 mapping technique and to accurately detect the diffuse myocardial fibrosis in HCM patients.

Background— Whether morphological abnormalities of the mitral valve represent part of the hypertrophic cardiomyopathy (HCM) disease process is unresolved. Therefore, we applied cardiovascular magnetic resonance to characterize mitral valve morphology in a large HCM cohort. Methods and Results— Cine cardiac magnetic resonance images were obtained in 172 HCM patients (age, 42±18 years; 62% men) and 172 control subjects. In addition, 15 HCM gene-positive/phenotype-negative relatives were studied. Anterior mitral leaflet (AML) and posterior mitral leaflet lengths were greater in HCM patients than in control subjects (26±5 versus 19±5 mm, P P 2 SDs above controls). Leaflet length was increased compared with controls in virtually all HCM age groups, including young patients 15 to 20 years of age (AML, 26±5 versus 21±4 mm; P =0.0002) and those ≥60 years of age (AML, 26±4 versus 19±2 mm; P P =0.09 and P =0.16, respectively). A ratio of AML length to LV outflow tract diameter of >2.0 was associated with subaortic obstruction ( P =0.001). In addition, AML length in 15 genotype-positive relatives without LV hypertrophy exceeded that of matched control subjects (21±3 versus 18±3 mm; P Conclusions— In HCM, mitral valve leaflets are elongated independently of other disease variables, likely constituting a primary phenotypic expression of this heterogeneous disease, and are an important morphological abnormality responsible for LV outflow obstruction in combination with small outflow tract dimension. These findings suggest a novel role for cardiac magnetic resonance in the assessment of HCM.

Background Chronic kidney disease is associated with a marked increase in risk for left ventricular hypertrophy and cardiovascular mortality compared with the general population. Therapy with vitamin D receptor activators has been linked with reduced mortality in chronic kidney disease and an improvement in left ventricular hypertrophy in animal studies. Purpose PRIMO ( Paricalcitol capsules benefits in Renal failure Induced cardia MOrbidity) is a multinational, multicenter randomized controlled trial to assess the effects of paricalcitol (a selective vitamin D receptor activator) on mild to moderate left ventricular hypertrophy in patients with chronic kidney disease. Methods Subjects with mild-moderate chronic kidney disease are randomized to paricalcitol or placebo after confirming left ventricular hypertrophy using a cardiac echocardiogram. Cardiac magnetic resonance imaging is then used to assess left ventricular mass index at baseline, 24 and 48 weeks, which is the primary efficacy endpoint of the study. Because of limited prior data to estimate sample size, a maximum information group sequential design with sample size re-estimation is implemented to allow sample size adjustment based on the nuisance parameter estimated using the interim data. An interim efficacy analysis is planned at a pre-specified time point conditioned on the status of enrollment. The decision to increase sample size depends on the observed treatment effect. A repeated measures analysis model, using available data at Week 24 and 48 with a backup model of an ANCOVA analyzing change from baseline to the final nonmissing observation, are pre-specified to evaluate the treatment effect. Gamma-family of spending function is employed to control family-wise Type I error rate as stopping for success is planned in the interim efficacy analysis. Limitations If enrollment is slower than anticipated, the smaller sample size used in the interim efficacy analysis and the greater percent of missing week 48 data might decrease the parameter estimation accuracy, either for the nuisance parameter or for the treatment effect, which might in turn affect the interim decision-making. Conclusions The application of combining a group sequential design with a sample-size re-estimation in clinical trial design has the potential to improve efficiency and to increase the probability of trial success while ensuring integrity of the study.

Background: In chronic kidney disease (CKD), left ventricular hypertrophy (LVH) is prevalent and is associated with increased cardiovascular morbidity and mortality. Vitamin D receptor (VDR) activation attenuates LVH progression in animal models. Methods: PRIMO is a multinational, randomized, double-blinded trial with oral paricalcitol in subjects with stages 3–4 CKD, mild-to-moderate LVH and an LV ejection fraction >50%. The primary endpoint is change in the left ventricular mass index (LVMI) compared with placebo after 48 weeks of treatment. The main secondary endpoints are changes in diastolic function parameters. In this paper, we report baseline characteristics from this study. Results: LVMI was 33.0 ± 7.5 g/m2.7 for males and 30.8 ± 7.2 g/m2.7 for females (p = 0.04). LVMI correlated with systolic blood pressure (r = 0.24), urine albumin creatinine ratio (r = 0.39), troponin T (r = 0.29), high-sensitivity C-reactive protein (r = 0.25) and plasma levels of B-type brain natriuretic peptide (r = 0.22); all p < 0.01. In multiple linear regression, each remained independently associated with LVMI. The early diastolic velocity of the lateral mitral annulus (E’) was 8.1 ± 2.4 cm/s. E’ was inversely correlated with age in univariate (r = –0.14, p = 0.04) and multivariable (p = 0.02) analysis. Conclusion: Among 227 multinational subjects with stages 3–4 CKD, baseline LVMI correlates with baseline blood pressure, urine albumin creatinine ratio and cardiac biomarkers, and baseline diastolic function correlates with age. This research was funded by Abbott Laboratories; ClinicalTrials.gov No. NCT00497146.

To determine the most reproducible semiautomated gray-scale thresholding technique for quantifying late gadolinium enhancement (LGE) in a large cohort of patients with hypertrophic cardiomyopathy (HCM).All study patients signed a statement approved by the internal review boards of the participating institutions, agreeing to the use of their medical information for research purposes. LGE cardiovascular magnetic resonance (MR) imaging was performed in 201 patients (71% male) with a mean age of 41.5 years ± 17.6 (standard deviation [SD]) by using standard techniques with administration of 0.2 mmol of gadopentetate dimeglumine per kilogram of body weight. The presence and quantity of LGE were determined first with visual assessment; then with gray-scale thresholds of 2 SDs, 4 SDs, and 6 SDs above the mean signal intensity for the normal remote myocardium; and then with 2 SDs above noise. The LGE quantifications were repeated 4 or more weeks apart to assess reproducibility. Bland-Altman analysis and correlation coefficients were used to compare the visual and various thresholding methods, with normally distributed variables expressed as means ± SDs.LGE was identified in 103 (51%) subjects. The mean quantity of LGE at visual analysis was 13 g ± 20 compared with 12 g ± 17 at 6 SDs, 25 g ± 23 at 4 SDs, 55 g ± 31 at 2 SDs, and 64 g ± 69 at 2 SDs above noise. All gray-scale thresholds were significantly correlated with visual assessment. The 6-SD threshold had the strongest correlation (r = 0.913, P.0001) compared with thresholds of 2 SDs (r = 0.81) and 4 SDs (r = 0.91) above the mean and 2 SDs above noise (r = 0.53) (P.001 for all comparisons). In addition, compared with visual assessment, the 6-SD threshold yielded less intraobserver variability (difference, 0.6 g ± 8, κ = 0.66 [P.0001] vs 1.4 g ± 9, κ = 0.49 [P.0001]) and less interobserver variability (difference, 5.4 g ± 18, κ = 0.20 [P.0001] vs -18.4 g ± 18, κ = 0.08 [P.0001]).Semiautomated LGE cardiovascular MR gray-scale thresholding with 6 or more SDs above the mean signal intensity for the visually normal remote myocardium yields the closest approximation of the extent of LGE identified with visual assessment and is highly reproducible. This objective method should be considered for quantifying LGE in patients with HCM.

The goal of this analysis was to determine the relation between myocardial infarct size and left ventricular (LV) ejection fraction (EF) in patients with ST-segment elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (pPCI) using cardiovascular magnetic resonance imaging (CMR). After STEMI, LVEF and infarct size correlate with prognosis, but the relation between infarct size and LVEF is incompletely known. Consecutive subjects presenting to a single center with STEMI treated with pPCI were enrolled, and cine functional and late gadolinium enhancement CMR was performed 3 months after presentation. From cine images, LVEF was calculated using volumetric summation of disks method. Infarct size was measured as percent LV myocardial volume with late gadolinium enhancement. In the 78 patients enrolled (mean age 54.5 years, range 42 to 82), median LVEF was 56% (interquartile range 49 to 62) and median infarct size was 11% (interquartile range 5 to 18). Of the 53 patients with infarct size15%, all had LVEF40%, and there was no significant relation between infarct size and LVEF (slope -0.43, R(2) = 0.045, p = 0.13). In patients with infarct sizeor =15%, there was a significant negative linear association between infarct size and LVEF (slope -1.21, R(2) = 0.66, p0.001), such that for every 5% increase in infarct size, there was a 6.1% decrease in LVEF. In conclusion, there is a negative linear relation between infarct size and LVEF for moderate to large infarcts. For small infarcts there is no significant relation between infarct size and LVEF. Up to 15% of LV myocardial volume may be infarcted before there is any appreciable decrease in LVEF.

In hypertrophic cardiomyopathy (HCM), the clinical significance attributable to the broad range of left ventricular (LV) systolic function, assessed as the ejection fraction (EF), is incompletely resolved. We evaluated the EF using cardiovascular magnetic resonance (CMR) imaging in a large cohort of patients with HCM with respect to the clinical status and evidence of left ventricular remodeling with late gadolinium enhancement (LGE). CMR imaging was performed in 310 consecutive patients, aged 42 +/- 17 years. The EF in patients with HCM was 71 +/- 10% (range 28% to 89%), exceeding that of 606 healthy controls without cardiovascular disease (66 +/- 5%, p0.001). LGE reflecting LV remodeling showed an independent, inverse relation to the EF (B-0.69, 95% confidence interval -0.86 to -0.52; p0.001) and was greatest in patients with an EF50%, in whom it constituted a median value of 29% of the LV volume (interquartile range 16% to 40%). However, the substantial subgroup with low-normal EF values of 50% to 65% (n = 45; 15% of the whole cohort), who were mostly asymptomatic or mildly symptomatic (37 or 82% with New York Heart Association functional class I to II), showed substantial LGE (median 5% of LV volume, interquartile range 2% to 10%). This overlapped with the subgroup with systolic dysfunction and significantly exceeded that of patients with an EF of 66% to 75% and75% (median 2% of the LV volume, interquartile range 1.5% to 4%; p0.01). In conclusion, in a large cohort of patients with HCM, a subset of patients with low-normal EF values (50% to 65%) was identified by contrast-enhanced CMR imaging as having substantial degrees of LGE, suggesting a transition phase, potentially heralding advanced LV remodeling and systolic dysfunction, with implications for clinical surveillance and management.

Purpose To compare higher spatial resolution 3D late gadolinium enhancement (LGE) cardiovascular magnetic resonance (Cardiac MR) with 2D LGE in patients with prior myocardial infarction. Materials and Methods Fourteen patients were studied using high spatial resolution 3D LGE (1.3 × 1.3 × 5.0 mm3) and conventional 2D LGE (2 × 2 × 8 mm3) scans. The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) were measured. Total infarct volume, peri-infarct volume measured in a limited slab, and papillary muscle scar volume were compared using Bland–Altman analysis. Image quality was graded. Results 3D LGE had higher scar SNR (P < 0.001), higher myocardial SNR (P = 0.001), higher papillary scar-blood CNR (P = 0.01), and greater sharpness (P = 0.01). The scar volumes agreed (14.5 ± 8.2 for 2D, vs. 13.2 ± 8.8 for 3D), with bias ± 2 standard deviations (SDs) of 0.5 ± 6.8 mL, P = 0.59 R = 0.91. The peri-infarct volumes correlated but less strongly than scar (P = 0.40, R = 0.77). For patients with more heterogeneous scar, larger peri-infarct volumes were measured by 3D (1.9 ± 1.1 mL for 2D vs. 2.4 ± 1.6 mL for 3D, P = 0.15, in the matched region). Papillary scar, present in 6/14 (42%) patients, was more confidently identified on 3D LGE. Conclusion Higher spatial resolution 3D LGE provides sharper images and higher SNR, but less myocardial nulling. Scar volumes agree well, with peri-infarct volumes correlating less well. 3D LGE may be superior in visualization of papillary muscle scar. J. Magn. Reson. Imaging 2009;30:794–800. © 2009 Wiley-Liss, Inc.

Background— Contrast-enhanced cardiovascular magnetic resonance with delayed enhancement (DE) can provide in vivo assessment of myocardial fibrosis. However, the clinical significance of DE in hypertrophic cardiomyopathy (HCM) remains unresolved. Methods and Results— Cine and cardiovascular magnetic resonance with DE were performed in 202 HCM patients (mean age, 42�17 years; 71% male), DE was compared with clinical and demographic variables, and patients were followed up for 681�249 days for adverse disease events. DE was identified in 111 (55%) HCM patients, occupying 9%�11% of left ventricular myocardial volume, including >25% DE in 10% of patients. The presence of DE was related to occurrence of heart failure symptoms ( P =0.05) and left ventricular systolic dysfunction ( P =0.001). DE was present in all patients with ejection fraction ≤50% but also in 53% (102/192) of patients with preserved ejection fraction ( P r =−0.3; P r =−0.4; P P =0.5). Conclusions— In a large HCM cohort, DE was an independent predictor of systolic dysfunction but with only a modest relationship to heart failure symptoms. These data suggest an important role for myocardial fibrosis in the clinical course of HCM patients but are not sufficient at this time to consider DE as an independent risk factor for adverse prognosis.

Increased thickness of the left ventricular (LV) wall is the predominant feature of the hypertrophic cardiomyopathy (HC) phenotype. The structural characteristics of the LV papillary muscles (PMs) have received little attention. In this study, cardiovascular magnetic resonance (CMR) was used to characterize PM morphology in a large HC population. Cine and delayed enhancement (DE) CMR images were obtained in 201 patients with HC and 43 control subjects. PM number and mass index were greater in patients with HC compared with controls (2.5 vs 2.1, p0.001, and 6 +/- 2 vs 3 +/- 2 g/m(2), p0.001, respectively), including 109 (54%) with PM massor =7 g/m(2) (or =2 SDs above the mean for controls). Greater LV wall mass index was associated with more substantial PM mass (r = 0.09, p0.001). Furthermore, 12 patients with HC (19%) had normal LV mass with localized wall thickness but increased PM mass. In patients with HC with LV outflow obstruction at rest, PMs were positioned closer to the ventricular septum (displaced anteriorly: 58% vs 42% for subjects without obstruction, p = 0.02), with more marked hypertrophy (9 +/- 5 vs 6 +/- 4 g/m(2), p0.001). Preoperative CMR identified 3 patients with accessory, anteriorly displaced PMs judged to contribute to outflow obstruction, which were resected during septal myectomy. DE of the PMs was identified in 13 patients with HC (6%), including 3 with DE confined to PMs. In conclusion, CMR demonstrates LV PMs to be part of the cardiomyopathic process in HC, with increases in number and mass, and not uncommonly associated with remodeling with DE. The identification of accessory PMs may be useful in planning preoperative strategy.

Background Impairment of coronary microvascular perfusion is common among patients with ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI). Cardiovascular magnetic resonance imaging (CMR) can identify microvascular obstruction (MO) following reperfusion of STEMI. We hypothesized that myocardial perfusion, as assessed by the Thrombolysis in Myocardial Infarction (TIMI) Myocardial Perfusion Grade (TMPG), would be associated with a CMR metric of MO in this population. Methods Twenty-one STEMI patients who underwent successful primary PCI were evaluated. Contrast-enhanced CMR was performed within 7 days of presentation and repeated at three months. TIMI Flow Grade (TFG), corrected TIMI Frame Count (cTFC), TMPG, MO, infarct size, and left ventricular ejection fraction (EF) were assessed. Results The median peak creatine phosphokinase (CPK) was 1,775 IU/l (interquartile range 838–3,321). TFG 3 was present following PCI in 19 (90%) patients. CMR evidence of MO was present in 52% following PCI. Abnormal post-PCI TMPG (0/1/2) was present in 48% of subjects and was associated with MO on CMR (90% MO with TMPG 0/1/2 vs. 18% MO with TMPG 3, P

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.

Hypertrophic cardiomyopathy (HCM) is the most common monogenic heart disease with a frequency as high as 1 in 200. In many cases, HCM is caused by mutations in genes encoding the different components of the sarcomere apparatus. Hypertrophic cardiomyopathy is characterized by unexplained left ventricular hypertrophy, myofibrillar disarray, and myocardial fibrosis. The phenotypic expression is quite variable. Although most patients with HCM are asymptomatic, serious consequences are experienced in a subset of affected individuals who present initially with sudden cardiac death or progress to refractory heart failure. The Hypertrophic Cardiomyopathy Registry study is a National Heart, Lung, and Blood Institute-sponsored 2,750-patient, 44-site, international registry and natural history study designed to address limitations in extant evidence to improve prognostication in HCM (NCT01915615). In addition to the collection of standard demographic, clinical, and echocardiographic variables, patients will undergo state-of-the-art cardiac magnetic resonance for assessment of left ventricular mass and volumes as well as replacement scarring and interstitial fibrosis. In addition, genetic and biomarker analyses will be performed. The Hypertrophic Cardiomyopathy Registry has the potential to change the paradigm of risk stratification in HCM, using novel markers to identify those at higher risk.

Omega-3 fatty acid (PUFAs) may have a number of beneficial pleiotropic effects. One randomized trial demonstrated significant survival benefit for PUFAs following acute MI. We conducted a randomized, double-blinded, placebo controlled trial of PUFA supplementation post acute MI. 358 patients were

Cardiovascular magnetic resonance (CMR) with extensive late gadolinium enhancement (LGE) is a novel marker for increased risk for sudden death (SD) in patients with hypertrophic cardiomyopathy (HC). Small focal areas of LGE confined to the region of right ventricular (RV) insertion to ventricular septum (VS) have emerged as a frequent and highly visible CMR imaging pattern of uncertain significance. The aim of this study was to evaluate the prognostic significance of LGE confined to the RV insertion area in patients with HC. CMR was performed in 1,293 consecutive patients with HC from 7 HC centers, followed for 3.4 ± 1.7 years. Of 1,293 patients (47 ± 14 years), 134 (10%) had LGE present only in the anterior and/or inferior areas of the RV insertion to VS, occupying 3.7 ± 2.9% of left ventricular myocardium. Neither the presence nor extent of LGE in these isolated areas was a predictor of adverse HC-related risk, including SD (adjusted hazard ratio 0.82, 95% confidence interval 0.45 to 1.50, p = 0.53; adjusted hazard ratio 1.16/10% increase in LGE, 95% confidence interval 0.29 to 4.65, p = 0.83, respectively). Histopathology in 20 HC hearts show the insertion areas of RV attachment to be composed of a greatly expanded extracellular space characterized predominantly by interstitial-type fibrosis and interspersed disorganized myocyte patterns and architecture. In conclusion, LGE confined to the insertion areas of RV to VS was associated with low risk of adverse events (including SD). Gadolinium pooling in this region of the left ventricle does not reflect myocyte death and repair with replacement fibrosis or scarring.

Over the past decade, coronary magnetic resonance imaging has been transformed from a scientific curiosity to a clinically useful imaging tool for patients with known or suspected anomalous coronary arteries or coronary artery aneurysms and for assessment of coronary artery bypass graft patency. Coronary magnetic resonance imaging also appears to be of clinical value for assessment of native vessel integrity in selected patients, especially those patients with suspected left main/multivessel disease. Among patients referred for X-ray angiography, a normal coronary magnetic resonance imaging strongly suggests the absence of severe multivessel disease. Technical and methodological advances in motion suppression, along with increasing clinical experience will no doubt facilitate improved visualization of the distal and branch vessel.

Background: Classification of patients with unstable angina (UA) by Agency for Health Care Policy and Research (AHCPR) guidelines in the emergency department reliably stratifies risk of death or myocardial infarction (MI) for triage to outpatient evaluation (low-risk), hospitalization (high-risk), or additional testing (intermediate-risk). Cardiac troponin-I elevation may identify patients at higher risk, but the incremental value may vary with AHCPR clinical risk. Hypothesis: The objective of this study was to determine whether cardiac troponin-I had any additional value beyond triage based upon history, physical examination, and electrocardiogram, in the evaluation of patients with UA. Methods: In all, 212 consecutive patients with UA and normal serum creatine kinase (CK)-MB levels and elevated troponin-I were risk stratified by AHCPR guidelines to evaluate the incremental value of adding routine troponin-I measurements to our current model for risk stratification. Results: Primary events (death/nonfatal MI) occurred in 35% of high-risk, 15% of intermediate-risk, and 0% of low-risk patients (p < 0.001 by chisquare for trend). High troponin-I (≥ 2.0 ng/dl) occurred in 48% of high-risk, 21% of intermediate-risk, and 19% of low-risk patients. The remaining patients in each risk group had indeterminate troponin-I levels (≥0.4 < 2 ng/dl). Of those with high troponin-I, a primary event occurred in 36, 42, and 0% in the respective high-, intermediate-, and low-risk groups (p < 0.001). High troponin-I levels corresponded with a statistically significant increased rate of primary events only in patients at AHCPR intermediate risk: 42.4 vs. 7.3%, p < 0.001. Conclusion: The AHCPR guidelines risk stratify patients with UA. High troponin-I adds significant (p < 0.001) prognostic value in the patients at AHCPR intermediate risk and should be evaluated further in larger trials of such patients.

Aims Cardiovascular magnetic resonance (CMR) has improved diagnostic and management strategies in hypertrophic cardiomyopathy (HCM) by expanding our appreciation for the diverse phenotypic expression. We sought to characterize the prevalence and clinical significance of a recently identified accessory left ventricular (LV) muscle bundle extending from the apex to the basal septum or anterior wall (i.e. apical–basal). Methods and results CMR was performed in 230 genotyped HCM patients (48 ± 15 years, 69% male), 30 genotype-positive/phenotype-negative (G+/P−) family members (32 ± 15 years, 30% male), and 126 controls. Left ventricular apical–basal muscle bundle was identified in 145 of 230 (63%) HCM patients, 18 of 30 (60%) G+/P− family members, and 12 of 126 (10%) controls (G+/P− vs. controls; P < 0.01). In HCM patients, the prevalence of an apical–basal muscle bundle was similar among those with disease-causing sarcomere mutations compared with patients without mutation (64 vs. 62%; P = 0.88). The presence of an LV apical–basal muscle bundle was not associated with LV outflow tract obstruction ( P = 0.61). In follow-up, 33 patients underwent surgical myectomy of whom 22 (67%) were identified to have an accessory LV apical–basal muscle bundle, which was resected in all patients. Conclusion Apical–basal muscle bundles are a unique myocardial structure commonly present in HCM patients as well as in G+/P− family members and may represent an additional morphologic marker for HCM diagnosis in genotype-positive status.

Atrial fibrillation (AF) is the most common sustained arrhythmia with 3 to 6 million currently afflicted and the prevalence expected to double by 2050.1 AF carries an increased risk of cardiovascular morbidity and mortality driven largely by increased risk of stroke and congestive heart failure.1 Management of AF represents a significant and growing healthcare burden, with an estimated cost of $6.65 billion in 2005 and likely doubling by 2020.2 Article see p 23 Treatment of AF historically consists of anticoagulation to reduce the incidence of clinical stroke followed by either rate control or rhythm control. Both choices have been shown to produce similar outcomes (Atrial Fibrillation Follow-up Investigation of Rhythm Management [AFFIRM]),3 and thus rhythm control has been recommended for those who are symptomatic. Until recently, rhythm control had been most commonly achieved with the use of repeated cardioversions and antiarrhythmic therapy—many of which have undesirable side effects and potential toxicities.4 Surgical treatment using the Maze procedure (and its many modifications) makes physiological sense (interfering with the macroreentrant circuit in the atria) but is quite invasive. The advent of catheter-based therapies for rhythm management of AF has revolutionized the electrophysiological field and provides a less invasive approach similar to the surgical Maze procedure goals. Pulmonary vein isolation (PVI), the most commonly used catheter-based technique, aims to electrically isolate the pulmonary veins, a major source of ectopy that may trigger AF,5 using catheter-based mapping and ablation tools.6 Despite the excitement and ensuing enormous industry growth in this field, PVI has been met with mixed long-term success with concerns of both short-term safety and long-term efficacy. As a result, treatment guidelines remain controversial.6,7 Several studies have demonstrated clinical features that predict long-term PVI success, including paroxysmal over persistent or permanent AF.8 …

Background— Hypertrophic cardiomyopathy (HCM) is the most common cause of sudden death in the young, although not all patients eligible for sudden death prevention with an implantable cardioverter-defibrillator are identified. Contrast-enhanced cardiovascular magnetic resonance with late gadolinium enhancement (LGE) has emerged as an in vivo marker of myocardial fibrosis, although its role in stratifying sudden death risk in subgroups of HCM patients remains incompletely understood. Methods and Results— We assessed the relation between LGE and cardiovascular outcomes in 1293 HCM patients referred for cardiovascular magnetic resonance and followed up for a median of 3.3 years. Sudden cardiac death (SCD) events (including appropriate defibrillator interventions) occurred in 37 patients (3%). A continuous relationship was evident between LGE by percent left ventricular mass and SCD event risk in HCM patients ( P =0.001). Extent of LGE was associated with an increased risk of SCD events (adjusted hazard ratio, 1.46/10% increase in LGE; P =0.002), even after adjustment for other relevant disease variables. LGE of ≥15% of LV mass demonstrated a 2-fold increase in SCD event risk in those patients otherwise considered to be at lower risk, with an estimated likelihood for SCD events of 6% at 5 years. Performance of the SCD event risk model was enhanced by LGE (net reclassification index, 12.9%; 95% confidence interval, 0.3–38.3). Absence of LGE was associated with lower risk for SCD events (adjusted hazard ratio, 0.39; P =0.02). Extent of LGE also predicted the development of end-stage HCM with systolic dysfunction (adjusted hazard ratio, 1.80/10% increase in LGE; P Conclusions— Extensive LGE measured by quantitative contrast enhanced CMR provides additional information for assessing SCD event risk among HCM patients, particularly patients otherwise judged to be at low risk.

In this issue of Radiology, Carlsson and colleagues report on the use of acute (1 hour, n = 7) and subacute (1 week, n = 6) resting first-pass perfusion and late gadolinium-enhanced cardiovascular magnetic resonance (MR) imaging to detect myocardial hypoperfusion and microinfarction in a swine model of coronary microembolization. They found resting hypoperfusion at 1 hour that persisted at 1 week. Detection of microinfarction was not reliable at 1 hour, but microinfarction was detected and characterized at 1 week. The pattern on late gadolinium-enhanced images in their model was patchy, with small clusters randomly distributed across a large artery territory. This is distinct from the subendocardially based transmural extension patterns described with clinical myocardial infarction (MI). The degree of left ventricular (LV) systolic dysfunction did not correlate with the quantity of myonecrosis.

Current guidelines recommend an implantable cardioverter-defibrillator (ICD) according to the left ventricular ejection fraction (LVEF). However, they do not mandate volumetric LVEF assessment. We sought to determine whether volumetric LVEF measurement using cardiovascular magnetic resonance imaging (CMR-LVEF) is superior to conventional LVEF measurement using 2-dimensional transthoracic echocardiography (Echo-LVEF) for risk stratifying patients referred for primary prevention ICD. Patients who underwent primary prevention ICD implantation at our institution and had undergone preimplantation CMR-LVEF from November 2001 to February 2011 were identified. Volumetric CMR-LVEF was determined from cine short-axis data sets. CMR-LVEF and Echo-LVEF were extracted from the clinical reports. The end point was appropriate ICD discharge (shock and/or antitachycardia pacing). Of 48 patients, appropriate ICD discharge occurred in 9 (19%) within 29 – 25 months (range 1 to 99, median 20). All patients met the Echo-LVEF criteria for ICD implantation; however 25% (95% confidence interval 13% to 37%) did not meet the CMR-LVEF criteria. None (0%) of these latter patients had received an appropriate ICD discharge. Using CMR-LVEF ≤30% as a threshold for ICD eligibility, 19 patients (40%) with a qualifying Echo-LVEF would not have been referred for ICD, and none (0%) received an ICD discharge. For primary prevention ICD implantation, volumetric CMR-LVEF might be superior to clinical Echo-LVEF for risk stratification and can identify a large minority of subjects in whom ICD implantation can be safely avoided. In conclusion, if confirmed by larger prospective series, volumetric methods such as CMR should be considered a superior “gatekeeper” for the identification of patients likely to benefit from primary prevention ICD implantation.

Background— Hypertrophic cardiomyopathy (HCM) is prominently associated with risk for sudden death and disease progression, largely in young patients. Whether patients of more advanced age harbor similar risks is unresolved, often creating clinical dilemmas, particularly in decisions for primary prevention of sudden death with implantable defibrillators. Methods and Results— We studied 428 consecutive HCM patients presenting at ≥60 years of age and followed for 5.8±4.8 years; 53% were women. Of the 428 patients, 279 (65%) survived to 73±7 years of age (range, 61–96 years), most (n=245, 88%) with no/mild symptoms, including 135 with ≥1 conventional sudden death risk factors and 50 (37%) with late gadolinium enhancement. Over follow-up, 149 (35%) died at 80±8 years of age, mostly from non–HCM-related causes (n=133, 31%), including a substantial proportion from noncardiac disease (n=54). Sixteen patients (3.7%) had HCM-related mortality events (0.64%/y), including embolic stroke (n=6), progressive heart failure or transplantation (n=3), postoperative complications (n=2), and arrhythmic sudden death events (n=5, 1.2% [0.20%/y]). All-cause mortality was increased in HCM patients ≥60 years of age compared with an age-matched US general population, predominantly as a result of non–HCM-related diseases ( P Conclusions— HCM patients surviving into the seventh decade of life are at low risk for disease-related morbidity/mortality, including sudden death, even with conventional risk factors. These data do not support aggressive prophylactic defibrillator implantation at advanced ages in HCM. Other cardiac or noncardiac comorbidities have a greater impact on survival than HCM in older patients.

We appreciate the comments by Puntmann et al on our manuscript.1 The authors suggest that myocardial crypts are a common morphologic finding in patients studied with cardiovascular magnetic resonance (CMR) including those with congenital heart disease and even in normal volunteers. On this point, we agree that myocardial crypts do not appear to be restricted to hypertrophic cardiomyopathy (HCM),2 although as we have suggested, additional systematic CMR-based studies in larger populations are necessary to precisely define the true prevalence of myocardial crypts in other forms of cardiovascular disease. In addition, apparent discrepancies noted with regard to the prevalence of crypts in these other populations may also simply be due …

Background— In hypertrophic cardiomyopathy (HCM), cardiovascular MR can detect morphological abnormalities of the left ventricle (LV) not visualized with echocardiography. Although myocardial crypts (ie, narrow, blood-filled invaginations within the LV wall) have been recognized in HCM, all clinical implications of these structural abnormalities within the broad clinical HCM spectrum are not completely resolved. Therefore, we sought to characterize the prevalence and diagnostic significance of myocardial crypts in HCM patients. Methods and Results— Cine and late gadolinium enhancement cardiovascular MR and 2-dimensional echocardiography were obtained in 292 consecutive patients with HCM including 31 genotype-positive/phenotype-negative family members without LV hypertrophy (28 ± 16 years; 51% male) and 261 patients with LV hypertrophy (46 ± 18 years; 60% male). Ninety-eight subjects without cardiovascular disease were controls. Myocardial crypts (1–6/patient) were identified only by cardiovascular MR in 19 of 31 genotype-positive/phenotype-negative patients (61%) compared with only 10 of 261 (4%) patients with HCM with LV hypertrophy ( P Conclusions— LV myocardial crypts represent a distinctive morphological expression of HCM, occurring with different frequency in HCM patients with or without LV hypertrophy. Crypts are a novel cardiovascular MR imaging marker, which may identify individual HCM family members who should also be considered for diagnostic genetic testing. These data support an expanded role for cardiovascular MR in early evaluation of HCM families.

Hypertrophic cardiomyopathy (HCM) is the most common, heritable cardiovascular disorder and the most frequent cause of sudden cardiac death (SCD) in young adults. Gender disparities with regards to clinical outcomes among HCM patients are not well-defined. We investigated the relationship between

Context Vitamin D is associated with decreased cardiovascular-related morbidity and mortality, possibly by modifying cardiac structure and function, yet firm evidence for either remains lacking. Objective To determine the effects of an active vitamin D compound, paricalcitol, on left ventricular mass over 48 weeks in patients with an estimated glomerular filtration rate of 15 to 60 mL/min/1.73 m 2 . Design, Setting, and Participants Multinational, double-blind, randomized placebo-controlled trial among 227 patients with chronic kidney disease, mild to moderate left ventricular hypertrophy, and preserved left ventricular ejection fraction, conducted in 11 countries from July 2008 through September 2010. Intervention Participants were randomly assigned to receive oral paricalcitol, 2 μg/d (n =115), or matching placebo (n = 112). Main Outcome Measures Change in left ventricular mass index over 48 weeks by cardiovascular magnetic resonance imaging. Secondary end points included echocardiographic changes in left ventricular diastolic function. Results Treatment with paricalcitol reduced parathyroid hormone levels within 4 weeks and maintained levels within the normal range throughout the study duration. At 48 weeks, the change in left ventricular mass index did not differ between treatment groups (paricalcitol group, 0.34 g/m 2.7 [95% CI, −0.14 to 0.83 g/m 2.7 ] vs placebo group, −0.07 g/m 2.7 [95% CI, −0.55 to 0.42 g/m 2.7 ]). Doppler measures of diastolic function including peak early diastolic lateral mitral annular tissue velocity (paricalcitol group, −0.01 cm/s [95% CI, −0.63 to 0.60 cm/s] vs placebo group, −0.30 cm/s [95% CI, −0.93 to 0.34 cm/s]) also did not differ. Episodes of hypercalcemia were more frequent in the paricalcitol group compared with the placebo group. Conclusion Forty-eight week therapy with paricalcitol did not alter left ventricular mass index or improve certain measures of diastolic dysfunction in patients with chronic kidney disease. Trial Registration clinicaltrials.gov Identifier: NCT00497146

Summary To test the hypothesis that fibrotic burden in remote myocardium quantified by CMR during early period of infarct healing is a strong determinant of the cardiac remodeling outcome. Background After acute myocardial infarction (AMI), co-existing myocardial stunning, ischemia, and architectural alteration may yield variable patterns of ventricular remodeling with potential long-term prognostic implications. We hypothesize that CMR quantification of fibrotic content, based on R1 (1/T1) assessment, in non-infarct myocardium early after infarction and during the infarct healing phases may provide novel prediction of the final infarct size and alteration of ventricular functions during infarct healing. Methods

In patients with recent MI, elevated fibrotic burden within the remote myocardium quantified by CMR is strongly associated with post-exercise heart rate variability (HRV) and QT dispersion (QTD). In contrast, infarct tissue heterogeneity demonstrated strong association with prolonged mean QRS duration at rest and during exercise. We postulate that these patterns of ischemic structural/arrhythmogenic affiliations during convalescent infarct healing, likely reflect differences in depolarization/repolarization characteristics of different post-ischemic myocardium and sympathetic innervation.

Hypothesis/Introduction : We investigated whether diabetes modified the effectiveness of renin–angiotensin–aldosterone system (RAAS) inhibition on left ventricular hypertrophy (LVH) regression in hypertensive patients in the Aliskiren in Left Ventricular Hypertrophy (ALLAY) trial. Materials and methods : Participants ( n =465) with LVH and a BMI > 25 kg/m 2 were randomized to aliskiren 300mg, losartan 100mg or both daily for 36 weeks, and LVH regression was assessed by cardiac magnetic resonance imaging. Renin concentration, plasma renin activity and aldosterone were assessed in a subset of patients. Results : Patients with diabetes mellitus (DM) ( n =111, 24%) were older (61±9 vs. 58±11 years, p =0.03), had higher BMI (32.2±4.2 vs. 30.7 ± 4 kg/m 2 , p =0.004), higher systolic blood pressure (148±14 vs. 145±14mmHg, p =0.03) and lower eGFR (79±16 vs. 84±16ml/min, p =0.03) at baseline. Combination therapy with aliskiren plus losartan was associated with greater LVH reduction than losartan alone in patients with DM ( p =0.01), but not in patients without DM ( p =0.91; unadjusted interaction p =0.06; adjusted p = 0.038). In a subset of 138 participants, plasma aldosterone was reduced to a greater extent in patients with DM ( p -interaction = 0.004). Conclusions : Patients with DM and LVH may derive differential benefit with dual RAAS inhibition with a combination of aliskiren and losartan compared with losartan alone with respect to LVH reduction. Whether these findings will result in improved outcomes will be further explored in larger studies.

Background: High circulating aldosterone levels stimulate myocardial fibrosis and left ventricular hypertrophy (LVH). However, it is not clear whether suppression of aldosterone directly contributes to LVH regression in hypertensive patients. Methods: The Aliskiren in Left Ventricular Hypertrophy (ALLAY) trial randomised 465 hypertensive overweight subjects with LVH to the direct renin inhibitor aliskiren 300 mg, losartan 100 mg or the combination and followed patients for 9 months. All patients were treated to standard blood pressure targets. Left ventricular (LV) mass index (LVMI) and LV wall thickness (LVWT) were assessed by cardiac magnetic resonance. A subset of 136 patients who had plasma aldosterone concentration (ALDO) measured at baseline and study end was analysed. Results: At baseline, plasma ALDO was modestly related to systolic blood pressure, LVMI, and wall thickness (all, p < 0.05). Aliskiren, either alone or in combination, was associated with a significantly greater reduction from baseline to 9 months in plasma aldosterone than losartan alone ( p < 0.02). Reduction in ALDO was related to reduction in LVMI even after adjustment for baseline ALDO, BP reduction and treatment group ( p for trend = 0.042). Conclusion: In hypertensive patients with increased LVWT, aliskiren alone or in combination with the angiotensin receptor blocker losartan provides greater reduction in aldosterone compared to losartan alone. Moreover, suppression of aldosterone was associated with reduction of LVH, independently of the change in SBP, suggesting that suppression of aldosterone, a known mediator of LVH, may be particularly important for LVH regression and as a target for therapy.

Background— Cell therapy for myocardial infarction (MI) may be limited by poor cell survival and lack of transdifferentiation. We report a novel technique of implanting whole autologous myocardial tissue from preserved myocardial regions into infarcted regions. Methods and Results— Fourteen rats were used to optimize cardiomyotissue size with peritoneal wall implantation (300 μm identified as optimal size). Thirty-nine pigs were used to investigate cardiomyotissue implantation in MI induced by left anterior descending balloon occlusion (10 animals died; male-to-female transplantation for tracking with in situ hybridization for Y chromosome, n=4 [2 donors and 2 MI animals]; acute MI implantation cohort at 1 hour, n=13; and healed MI implantation at 2 weeks, n=12). Assessment included echocardiography, magnetic resonance imaging, hemodynamics, triphenyltetrazolium chloride staining, and histological and molecular analyses. Tracking studies demonstrated viable implants with donor cells interspersed in the adjacent myocardium with gap junctions and desmosomes. In the acute MI cohort, treated animals compared with controls had improved perfusion by magnetic resonance imaging (1.2±0.01 versus 0.86±0.05; P P =0.04; triphenyltetrazolium chloride: anterior wall, 10.3±4.6% versus 28.9±5.8%, P P P P =0.006) than control animals. Infarcts in the treated animals contained more mdr-1 + cells and fewer c-kit + cells with a trend for decreased expression of matrix metalloproteinase-2 and increased expression of tissue inhibitor of metalloproteinase-2. Conclusion— Autologous cardiomyotissue implanted in an MI area remains viable, exhibits electromechanical coupling, decreases infarct size, and improves left ventricular function.

Methods Phantom studies A collection of phantoms (505-302 ms T1s, in 50 ms increments) with known T1s were imaged using LGE sequences, with scan parameters: 1RR between inversions, TR/TE/θ = 5.7 ms/3.4 ms/20o, 1.5 × 1.5 × 5 mm, 20 viewsper-segment, sequential order. The phantom with T1 = 505 ms represented "normal myocardium" and the phantom with T1 = 302 ms represented "scar". The myocardial signal was nulled, and scar and grey zone thresholds were calculated using 50% of maximal SI (2) in scar and maximal SI in the "normal myocardium" (2). The LGE sequence was acquired at higher SNR, and at optimal TI and optimal TI ± 30 ms.

Background Extreme magnitude of left ventricular hypertrophy (LVH) is an established risk factor for sudden death in hypertrophic cardiomyopathy (HCM), while myocardial scarring identified by contrast-enhanced cardiovascular magnetic resonance (CMR) may aid in risk stratification strategies. However, whether 12-lead ECG patterns are reliable for assessing magnitude of LVH or myocardial scarring by CMR in patients with HCM is unresolved. Therefore, we sought to determine the clinical utility of the ECG in a large HCM cohort with respect to these two clinical markers, using CMR, a high resolution 3-dimensional imaging technique.