p.17 抽出テキスト
September 25, 2018 Circulation. 2018;138:e272–e391. DOI: 10.1161/CIR.0000000000000549 e288 CLINICAL STATEMENTS AND GUIDELINES disease is required in patients with or at high risk for VA or SCD, including patients with cardiomyopathy, HF, prior MI, family history of cardiomyopathy or SCD, or an inherited structural heart disease associated with SCD. Echocardiography is the most readily available and commonly used imaging technique.S4.2.4-1,S4.2.4-2 LVEF is a strong, independent predictor of SCD and cardiovascular mortality and a determinant of eligibility for ICD implantation for primary prevention of SCD.S4.2.4-1 In SCD-HeFT (the Sudden Cardiac Death in Heart Failure Trial),S4.2.4-2 the benefit of the ICD was not dependent on the modality (ie, echocardiography, radionuclide angiography, or contrast angiograms) by which the LVEF was assessed. In clinical practice, if cardiac CTS4.2.4-3 or cardiac MRI has been performed and provides sufficient evaluation, echocardiography may be unnecessary. This recommendation for imaging differs from that of the 2017 ACC/AHA/HRS syncope guidelineS4.2.4-4 that applies to patients who may not have VA. 2. VA or SCA can be an initial manifestation of ischemic heart disease, cardiomyopathic processes, or myocarditis. Cardiac CT and cardiac MRI allow for evaluation of structural heart disease and assessment of LV and RV function including quantification of LVEF, LV mass and volume, valvular structure and coronary anatomy including anomalous coronary origins. Cardiac MRI can be useful in the evaluation for myocardial scar and infiltrative processes evident as late gadolinium enhancement.S4.2.4-5–S4.2.4-9 Cardiac MRI also provides high-quality assessment of LV and RV function, size, and degree of fibrosis and is particularly useful in arrhythmogenic right ventricular cardiomyopathy and HCM. 4.2.5 Biomarkers Recommendation for Biomarkers Referenced studies that support the recommendation are summarized in Online Data Supplement 7. COR LOE Recommendation IIa B-NR 1. In patients with structural heart disease, measurement of natriuretic peptides (BNP or N-terminal pro-BNP) can be useful by adding prognostic information to standard risk factors for predicting SCD or SCA.S4.2.5-1–S4.2.5-4 Recommendation-Specific Supportive Text 1. Elevated levels of natriuretic peptides—B-type natriuretic peptide (BNP) or N-terminal pro-BNP—are associated with increased risk of SCA and appropriate ICD therapies, even after adjustment of LVEF and other risk factors.S4.2.5-1–S4.2.5-4 These biomarkers are also predictive of nonsudden cardiovascular mortality and thus are not specific to SCD risk alone. Natriuretic peptides have also been evaluated for predicting SCD in the general population.S4.2.5-5,S4.2.5-6 In the Nurses’ Health Study, an elevated N-terminal pro-BNP was an independent risk marker for SCD in presumably healthy women.S4.2.5-5 In an older adult population, higher baseline levels of N-terminal pro-BNP were associated with SCD over a 16-year follow-up period.S4.2.5-6 These biomarkers may also have a potential role in facilitating the identification of individuals at increased risk of SCD and VA in the general population, particularly in those at intermediate or high risk of ischemic heart disease, but further studies are needed. Use of biomarkers has not been shown to be useful for selecting patients for ICDs. A study of 4431 patients found high-sensitivity troponin to be only weakly predictive of SCD.S4.2.5-7 However, there are no data on whether high-sensitivity troponin can improve the current SCD prediction algorithms. 4.2.6 Genetic Considerations in Arrhythmia Syndromes Recommendation for Genetic Counselling* COR LOE Recommendation I C-EO 1. In patients and family members in whom genetic testing for risk stratification for SCA or SCD is recommended, genetic counseling is beneficial. *Please refer to section 7.9 for disease-specific recommendations. Synopsis The diagnosis of most inherited arrhythmia syndromes is based on clinical features and family history. The availability of genetic testing for inherited arrhythmia syndromes can: 1) provide opportunity to confirm a suspected clinical diagnosis and sometimes provide prognostic information for the proband and 2) offer cascade screening of potentially affected family members when a disease-causing mutation is identified in the proband. The yield of genetic testing varies by disease. The verification of pathogenicity of suspected mutations is an evolving field, and exome sequencing has identified an increasing number of variants of uncertain significance in the general population.S4.2.6-1–S4.2.6-5 Genotyping can have therapeutic implications for some arrhythmogenic phenotypes such as long QT syndrome and Fabry’s disease,S4.2.6-6–S4.2.6-9 where a monogenic pathogenic mutation has been clearly identified, the risk to mutation positive individuals has been extensively studied, and effective therapy relevant to the mutation can be instituted. In other diseases, such as Brugada syndrome, the role of a clear monogenic disease-causing mutation is less certain, and the genotype does not provide therapeutic or prognostic information for the proband.S4.2.6-5,S4.2.6-10–S4.2.6-12 In arrhythmogenic right ventricular cardiomyopathy, some Downloaded from http://ahajournals.org by on October 7, 2026