p.79 抽出テキスト

September 25, 2018 Circulation. 2018;138:e272–e391. DOI: 10.1161/CIR.0000000000000549 e350

CLINICAL STATEMENTS AND GUIDELINES HELP-VT trial,S12-4 epicardial ablation was required in 30% of patients with VT related to NICM compared with 1.2% of patients with ischemic cardiomyopathy. A wide QRS with marked slurring of the initial portion of the QRS and a QS complex in the lateral or inferior leads during VT suggests an epicardial circuit in NICM, but the ECG does not reliably predict epicardial VT locations in patients with prior MI. Preprocedural cardiac MRI and intraprocedural electroanatomic mapping are useful tools to guide the localization of epicardial scar that may be the source of reentrant VT.S12-8,S12-10 Pericardial adhesions prevent percutaneous access in some patients, notably many with prior cardiac surgery. Percutaneous pericardial access for mapping and ablation is associated with a serious complication rate of approximately 5% and tamponade from RV puncture or laceration that can require emergent surgery or be fatal, coronary artery injury and phrenic nerve injury can occur.S12-11,S12-12 Reported experience is from tertiary referral centers.

13 POSTMORTEM EVALUATION

OF SCD

Recommendations for Postmortem Evaluation of SCD References that support the recommendations are summarized in Online Data Supplement 58.

COR LOE Recommendations

I B-NR 1. In victims of SCD without obvious causes, a standardized cardiac-specific autopsy is recommended.S13-1,S13-2

I B-NR 2. In first-degree relatives of SCD victims who were 40 years of age or younger, cardiac evaluation is recommended, with genetic counseling and genetic testing performed as indicated by clinical findings.S13-3

IIa B-NR 3. In victims of SCD with an autopsy that implicates a potentially heritable cardiomyopathy or absence of structural disease, suggesting a potential cardiac channelopathy, postmortem genetic testing is reasonable.S13-4–S13-7

IIa C-LD 4. In victims of SCD with a previously identified phenotype for a genetic arrhythmiaassociated disorder, but without genotyping prior to death, postmortem genetic testing can be useful for the purpose of family risk profiling.S13-8

Recommendation-Specific Supportive Text

1.	 A comprehensive postmortem protocol has been recommended for the routine evaluation of subjects (typically  <40 years of age) who die suddenly without a prior diagnosis of a condition and circumstances of death that could be reasonably implicated in the cause of unexpected SCD.S13-1 One study documented the added value of postmortem examination at a specialized cardiac pathology center,S13-2 with particular value for clarifying an apparent overdiagnosis of cardiomyopathy by nonspecialized centers. Pathological findings limited to the specialized conduction system were demonstrated in 22% of cases.S13-9 A misdiagnosis of cardiomyopathy was reported in 37% of referred cases that were ultimately determined to be structurally normal. The etiologic data for specialized cardiac evaluation are not generalizable to the overall population because of skewing of age at the time of SCD. In another study of SCD patients at ages ranging from <1 year to >80 years (mean, 38.2 years; median, 38 years), the peak incidence of SCD occurred between the ages of 31 and 60 years, with a 5- to 7-fold excess of males/females in that age range.S13-10 For the overall group, 42% of SCD were due to ischemic heart disease, 12% viral myocarditis, and 5% cardiomyopathy, with 15% being unexplained by autopsy. For the subgroup <35 years of age, 13.5% were attributed to ischemic heart disease and 24.9% were unexplained. In the subgroup >55 years of age, only 0.8% were unexplained. In patients who die suddenly despite an ICD, interrogation of the ICD is important to confirm proper device functioning and can provide information on the mechanism of death. 2.	 Comprehensive cardiac screening including 12-lead ECG, possible signal averaged ECG, echocardiogram, and ambulatory rhythm monitoring or exercise testing of first-degree relatives of decedents with sudden unexpected death may identify a probable heritable cardiac cause of death in up to 30% of cases.S13-11–S13-13 Genetic testing should be targeted based on the results of initial evaluation.S13-3 Genetic testing in selected first-degree relatives may result in identification of inherited conditions including long QT syndrome, catecholaminergic polymorphic ventricular tachycardia, Brugada syndrome, arrhythmogenic right ventricular cardiomyopathy, and HCM in 4% to 30% of families.S13-11,S13-12,S13-14

3.	 For the purpose of family risk profiling, it is important to use the disease-specific genetic test panel that corresponds to the autopsy findings. Risk profiling of family members of an SCD victim suspected of having an inherited cardiomyopathy at autopsy is important. Although phenotyping of surviving family members is crucial, genotyping of the SCD proband provides a mechanism for efficient follow-up evaluation of those relatives with the disease-causing mutation found

Downloaded from http://ahajournals.org by on October 7, 2026