Identification of genomic differences among peripheral arterial beds in atherosclerotic and healthy arteries

Abstract Calcification is independently associated with cardiovascular events and morbidity. The calcification burden in atherosclerotic lesions quantitatively and qualitatively differs between arterial beds. Cardiovascular risk factors (CVRF) differentially affect plaque development between arterial beds. The aim of this study was to evaluate the impact of CVRF on atherosclerotic plaque calcification and to further study the molecular arterial heterogeneity that could account for these differences. Histological analysis was performed on atherosclerotic plaques from 153 carotid, 97 femoral and 28 infrapopliteal arteries. CVRF showed minor associations with plaque calcification: age and hypertension affected only the overall presence of calcification but not the type of the calcification, which significantly differed between arterial beds. Transcriptome analysis revealed distinct gene expression profiles associated with each territory in atherosclerotic and healthy arteries. Canonical pathway analysis showed the preferential involvement of immune system-related processes in both atherosclerotic and healthy carotid arteries. Bone development-related genes were among those mostly enriched in atherosclerotic and healthy femoral arteries, which are more prone to developing endochondral calcification. This study highlights the heterogeneous nature of arteries from different peripheral vascular beds and contributes to a better understanding of atherosclerosis formation and evolution

Clinical Yield of Familial Screening After Sudden Death in Young Subjects

International audienceBACKGROUND:After sudden cardiac death with negative autopsy, clinical screening of relatives identifies a high proportion of inherited arrhythmia syndrome. However, the efficacy of this screening in families not selected by autopsy has never been assessed. We aim to investigate the value of clinical screening in relatives of all subjects who died suddenly before 45 years of age.METHODS AND RESULTS:One hundred and three consecutive families who experienced unexplained sudden cardiac death before 45 years of age were included from May 2009 to December 2014 in a prospective multicenter registry. Clinical screening was provided to all relatives and performed in 64 families (230 relatives, 80 unexplained sudden cardiac death). Diagnosis was established in 16 families (25%), including Brugada syndrome (7), long QT syndromes (5), dilated cardiomyopathy (2), and hypertrophic cardiomyopathy (2). The diagnostic yield was mainly dependent on the number of screened relatives (3.8±3.4 screened relatives in diagnosed families versus 2.0±1.5; P<0.005) rising to 47% with at least 3 relatives. It additionally increased from 3 of 32 (9%) to 9 of 22 (41%) when both parents were screened (P=0.01). Diagnostic performance was also dependent on the exhaustiveness of screening (70% of complete screening in the diagnosed families versus 25%; P<0.0001) with 17 Brugada syndromes and 15 long QT syndromes diagnosed based on pharmacological tests.CONCLUSIONS:Even without autopsy, familial screening after sudden death in young patients is effective. Broad screening of relatives and systematic tests, including pharmacological challenges, greatly increases the likelihood of diagnosis in families

Sodium-channel blocker challenge in the familial screening of Brugada syndrome: safety and predictors of positivity

International audienceBackground - Sodium-channel blocker challenge (SCBC) is frequently performed to unmask Brugada syndrome. Objective - We aim to identify predictors of positivity and complications of SCBC in the setting of familial screening of Brugada syndrome. Methods - All consecutive patients from 2000 to 2014 who benefit from a sodium-channel blocker and belong to a family with at least 2 subjects affected by the syndrome were enrolled and followed prospectively. Data were reviewed by 2 physicians blinded to the clinical and genetic status. Results - Of the 672 SCBCs performed in 137 families, 337 (50%) were positive. Multivariate analysis identified ajmaline (odds ratio [OR] 2.98; 95% CI 1.65-4.91) and a significant S wave in lead DII (OR 3.11; 95% CI 2.12-4.58), DIII (OR 2.75; 95% CI 1.78-4.25), or V (OR 3.71; 95% CI 2.54-5.44) as predictors of a positive SCBC (P < .0001). Eleven patients (1.6%) presented complications (10 ventricular arrhythmias and 1 atrial flutter), but no deaths occurred. Familial history of complications (OR 41; lower quartile, upper quartile 10, 203; P < .0001), young age (P = .04), and decreased electrocardiographic conduction parameters at baseline (P = .04) were predictors of complications. QRS enlargement during SCBC was not associated with complications. During a median follow-up of 106 months (lower quartile, upper quartile 54, 143 months), 11 life-threatening arrhythmias occurred. Conclusion - SCBC in the screening of familial Brugada syndrome is safe. The risk of complication is considerably increased in the case of familial history of complicated SCBC, in young patients, and in the presence of decreased electrocardiographic conduction parameters. However, QRS enlargement during the test is not directly related to complications and should not be used to prematurely stop the test unless leading to false-negative results