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We sought to determine the feasibility and accuracy of dual-source computed tomography (DSCT) in assessing coronary artery disease and myocardial fibrosis of hypertrophic cardiomyopathy (HCM) compared with cardiac magnetic resonance (CMR) imaging and coronary angiography (CA). Forty-seven consecutive patients with HCM were prospectively enrolled. DSCT images were acquired in the arterial and late phases following intravenous contrast medium. The CMR and CA were performed within 7 days. Independent blinded readers read each study. Patients were classified according to myocardial delayed enhanced (MDE) CMR, coronary artery stenosis by CA, and arterial and MDE-DSCT. The diagnostic accuracy of DSCT in detecting coronary stenosis and MDE was analysed. Wall thickness determined by DSCT was strongly correlated with MR results (r = 0.91). DSCT and CMR MDE showed substantial agreement for the detection of myocardial fibrosis on per-patient and per-segment levels. The CT classification of patients by arterial stenosis and delayed enhancement had excellent agreement with MR and CA methods. The comprehensive cardiac CT examination provides reliable coronary artery and myocardial assessments. MDE-DSCT is a robust alternative method to MDE-CMR in assessing myocardial fibrosis in HCM particularly in patients with pacemakers or other contraindications to CMR. • Enhanced cardiac CT provides comprehensive assessment of patients with hypertrophic cardiomyopathy (HCM). • Myocardial delayed enhanced-CT has comparable accuracy to MDE-MR in detecting HCM fibrosis. • MDE-CT provides a robust alternative for HCM patients with MR contraindications.

Hypertrophic cardiomyopathy (HCM) is a major cause of sudden cardiac death. Mutations in the MYBPC3 gene represent the cause of HCM in ~35% of patients with HCM. However, genetic testing in clinic setting has been limited due to the cost and relatively time-consuming by Sanger sequencing. Here, we developed a HCM Molecular Diagnostic Kit enabling ultra-low-cost targeted gene resequencing in a large cohort and investigated the mutation spectrum of MYBPC3. In a cohort of 114 patients with HCM, a total of 20 different mutations (8 novel and 12 known mutations) of MYBPC3 were identified from 25 patients (21.9%). We demonstrated that the power of targeted resequencing in a cohort of HCM patients and found that MYBPC3 is a common HCM-causing gene in Chinese patients. Phenotype-genotype analyses showed that the patients with double mutations (n = 2) or premature termination codon mutations (n = 12) showed more severe manifestations, compared with patients with missense mutations (n = 11). Particularly, we identified a recurrent truncation mutation (p.Y842X) in four unrelated cases (4/25, 16%), who showed severe phenotypes and suggest that the p.Y842X is a frequent mutation in Chinese HCM patients with severe phenotypes.

Background and Purpose: Hypertrophic cardiomyopathy (HCM) is a common inherited cardiac disease and a major cause of sudden cardiac death. Mutations in the gene encoding the myosin binding protein C (MYBPC3) represent the cause of HCM in ~35% of all cases of HCM. However, genetic testing for MYBPC3 in clinic setting has been limited due to the cost and relatively time-consuming Sanger sequencing. Therefore, we developed a HCM gene diagnostic kit enabling ultra-low-cost candidate gene targeted resequencing in a large cohort. Methods: Clinical evaluations, electrocardiography and echocardiography data of all patients with HCM were collected in Anzhen Hospital, Beijing, from 2012 to 2013. Exomes were captured with MYBPC3-containing panel using biotinylatedoligo-probes and sequenced by Illumina HiSeq2000. Results: In a cohort of 114 patients with HCM, a total of 21 different mutations in the MYBPC3 gene, including 3 nonsense, 6 indels and 12 missense mutations, were identified from 29 patients. These patients were presented in a broad range of phenotypes with mean age of 36.6 ± 12.5 years at onset. Phenotype-genotype analyses showed that clinical manifestations (NYHA class 3~4) were more severe in the double-mutation group (n=3, 100%) as well as the premature termination codon (PTC) group (n=12, 50%), compared with the missense mutation group (n=14, 21.4%) (p=0.03). Interestingly, the p.Y842X mutation was detected in four unrelated cases (4/29, 13.79%) with severe phenotypes, such as syncope, arrhythmias, and history of receiving invasive therapies. Conclusions: We demonstrated that the power of targeted resequencing in a cohort of HCM patients, and found that MYBPC3 is a common HCM-causing gene in Chinese patients (~25.4%). We also confirmed that truncation mutations or double mutations in MYBPC3 could lead to relatively severe phenotypes, and propose that the p.Y842X mutation might be correlated with severe phenotypes in Chinese patients with HCM.

Desmin-related myopathy (DRM) is known to cause different types of cardiomyopathy. Late gadolinium enhancement cardiovascular magnetic resonance (CMR) has been shown to identify fibrosis in ischemic and non-ischemic cardiomyopathies. We present a rare case of desmin-related hypertrophic cardiomyopathy, CMR revealed fibrosis in the lateral wall of the left ventricle. CMR is superior to conventional echocardiography for the detection of myocardial fibrosis in desmin-related cardiomyopathy, which may be useful to detect early cardiac involvement and predict the patient prognosis.

To evaluate the immediate and follow-up results of percutaneous transluminal septal myocardial ablation (PTSMA) in patients with hypertrophic obstructive cardiomyopathy (HOCM).Fifteen symptomatic, drug-refractory patients with HOCM underwent PTSMA procedures with application of a myocardial contrast echocardiography (MCE) intra-procedure. Before and after the procedure, clinical evaluations were obtained in all patients, who were followed up for a mean period of 8.6 +/- 3.8 (6-20) months.Immediate left ventricular outflow tract gradient (LVOTG) reduction was achieved (77.93 +/- 22 mm Hg vs 14.8 +/- 15 mm Hg, P0.0001) after the procedure with a mean decrease of 5.75 +/- 2.87 mm Hg of left ventricular end diastolic pressure (P0.001). Follow up results revealed that ventricular remodelling occurred mainly 1-3 months after the procedure, but without evidence of ventricular dilation and contract dysfunction. Heart function (NYHA) was greatly improved (3.4 +/- 0.5 vs 1.1 +/- 0.4, P0.001) and exercise endurance increased. A renewed increase of LVOTG was found in 2 patients during follow-up.LVOTG was greatly decreased in HOCM patients undergoing a PTSMA procedure, and their symptoms were greatly improved without cardiac complications during follow-up. Sub-selection and reopening of target vessels were the causes of renewed increase of LVOTG, and this can be avoided with the accumulation of experience. This is a promising method for the treatment of symptomatic patients with HOCM.