AIMS: Next to left ventricular (LV) @entity1184 , @entity1121 ( @entity1121 ) is characterized by @entity409 and reduced myocardial external efficiency (MEE). Insights into the presence of these abnormalities as early markers of disease are of clinical importance in risk stratification, and development of therapeutic approaches. Therefore, the aim was to investigate myocardial perfusion and energetics in genotype-positive, phenotype-negative @entity1121 subjects (carriers). METHODS AND RESULTS: Fifteen carriers of an @entity18963 mutation underwent [ @entity8493 ]water positron emission tomography (PET) to assess @entity296 ( @entity296 ). @entity18808 PET was performed to obtain myocardial @entity26 consumption (MVO(2)). By use of cardiovascular magnetic resonance imaging, LV volumes and mass were defined to calculate MEE, i.e. the ratio between external work and MVO(2). Eleven healthy, genotype-negative, family relatives underwent similar scanning protocols to serve as a control group. Left ventricular mass was comparable between carriers and controls (93    25 vs. 99    21 g, P= 0.85), as was @entity296 at rest (1.19    0.34 vs. 1.18    0.32 mL @entity1009 ) g(-1), P= 0.92), and during hyperaemia (3.87    0.75 vs. 3.96    0.86 mL @entity1009 ) g(-1), P= 0.77). Myocardial @entity26 consumption averaged 0.137    0.057 mL @entity1009 ) g(-1) in carriers and was not significantly different from controls (0.125    0.043 mL @entity1009 ) g(-1), P= 0.29). Cardiac work, however, was slightly reduced in carriers (7398    1384 vs. 9139    2484 mmHg mL in controls, P= 0.08). As a consequence, MEE was significantly decreased in carriers (27    10 vs. 36    8% in controls, P= 0.02). CONCLUSION: Carriers display reduced myocardial work generation in relation to @entity26 consumption, in the absence of @entity1184 and @entity854 . Hence, impaired myocardial energetics may constitute a primary component of @entity1121 pathogenesis.

Carriers of the XXXX @entity18963 mutation are characterized by reduced myocardial efficiency in the absence of @entity1184 and @entity409 .

@entity296 :: ('MESH:D009202', 'Disease') :: ['MBF', 'myocardial blood flow'] @entity1184 :: ('MESH:D006984', 'Disease') :: ['hypertrophy'] @entity1009 :: ('966', 'Gene') :: ['min(-1'] @entity26 :: ('MESH:D010100', 'Chemical') :: ['oxygen'] @entity409 :: ('MESH:D008107', 'Disease') :: ['microvascular dysfunction'] @entity18963 :: ('4607', 'Gene') :: ['MYBPC3'] @entity854 :: ('MESH:D018376', 'Disease') :: ['flow abnormalities'] @entity8493 :: ('CHEBI:36932', 'Chemical') :: ['(15)O'] @entity18808 :: ('MESH:C438206', 'Chemical') :: ['[(11)C]acetate'] @entity1121 :: ('MESH:D002312', 'Disease') :: ['HCM', 'hypertrophic cardiomyopathy']
@entity1121 :: (MESH:D002312,Disease) :: ['hypertrophic cardiomyopathy']
