4) All patients with first-, second-, or third-degree relatives affected by HCM or DCM should be evaluated with an ECG and echocardiogram and referred to a cardiologist familiar with diagnosis, genetics, and treatment of these conditions if abnormalities are found. CASE REPORTS Case Report 1 An 18-year-old athlete presented for a PPE prior to participating in competitive swimming. He is healthy, has no trouble keeping up with his peers in training, and has never had exertional chest discomfort, shortness of breath out of proportion to the level of activity, syncope, or presyncope with exercise. His physical examination results were unremarkable. He reported that his brother was diagnosed with HCM at age 16 by genetic testing, which revealed a wellestablished mutation in the gene MYH7 (p.R403Q). A family history reveals that his mother was diagnosed with HCM at age 44 based on family screening. There is no reported family history of sudden death. He had a normal echocardiogram and ECG result and had targeted testing for the MYH7 mutation and was found to not carry this genetic variant. He was allowed to compete in swimming. Case Report 2 A 20-year-old athlete reported for a PPE prior to the competitive basketball season. He is healthy, has not had symptoms of exertional chest pain, dyspnea, or syncope, and competes at a high level. He reported a family history of DCM diagnosed in his father at age 65 following two myocardial infarctions, the first at age 52 and necessitated coronary artery bypass surgery. Family history inquiry reveals that no other family members carry the diagnosis or have been told that they have abnormally enlarged or thickened hearts. There is no family history of sudden death. The DCM in his father was attributed to coronary artery disease, and the athlete was allowed to participate. References 1. Fokstuen S, Lyle R, Munoz A, et al. A DNA resequencing array for pathogenic mutation detection in hypertrophic cardiomyopathy. Hum. Mutat. 2008; 29:879Y85. 2. Gersh BJ, Maron BJ, Bonow RO, et al. 2011 ACCF/AHA guideline for the diagnosis and treatment of hypertrophic cardiomyopathy: executive summary: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Circulation. 2011; 124:2761Y96. 3. Morita H, Rehm HL, Menesses A, et al. Shared genetic causes of cardiac hypertrophy in children and adults. N. Engl. J. Med. 2008; 358:1899Y908.

Family History of Inherited Arrhythmic Disease from Family History Section Marco Perez, MD

Question 8c. Does anyone in your family have an inherited arrhythmic condition such as long QT, Brugada, catecholaminergic polymorphic ventricular tachycardia (CPVT), short QT, or early repolarization/J wave syndrome? 340

Volume 14 & Number 4 & July/August 2015

This question is looking for familial disorders associated with exertional SCD that are primarily due to abnormalities in ion channels and are not typically related to structural cardiac disease. Long QT syndrome is the most common of these disorders, with a prevalence of approximately 1 in 2,000 in the United States (4). Because these conditions are rare in the general population, the diagnosis is challenging, as screening physicians are unfamiliar with the presentation and diagnostic workup, patients are often asymptomatic, and characteristic findings on the electrocardiography (ECG) may be transient (3). FOLLOW-UP QUESTIONS To determine the importance of a positive answer to these questions, the following questions should be asked:

1) Who in your family carries the diagnosis, and at what age was the diagnosis made? These inherited arrhythmias usually follow an autosomaldominant pattern of inheritance, so an affected first-degree relative, such as a parent or sibling, confers a 50% risk of carrying the genetic susceptibility and a second-degree relative, such as a grandparent or aunt/uncle, a 25% risk. The yield of screening relatives that are further removed is lower. Although these conditions can present at any age, an early presentation increases the likelihood that the family member was indeed affected by an inherited condition.

2) How was the diagnosis made? The inherited arrhythmias are often misdiagnosed (5), which makes review of the family member diagnosis records essential. Long QT syndrome, for example, can be misdiagnosed due to an inaccurate measurement of the QT interval on the ECG or acquired causes such as the use of QT-prolonging medications can be attributed to genetics. Brugada syndrome, most common in people of Asian descent, can be misdiagnosed when the ECG is suspicious but does not meet the criteria for a classic ‘‘type I’’ Brugada pattern (1) or if the finding is made incidentally in an asymptomatic person. The diagnostic criteria for early repolarization/J wave syndrome has been particularly challenging due to disagreement over the exact definition of the ECG findings and because some of these findings are commonly found in the general population (2).

3) Has anyone in your family had genetic testing for these heart conditions? This question is most helpful when the diagnosis is clear clinically and a causative variant of high confidence has been identified. In this scenario, family members can be screened with targeted genetic testing. However, the yield of genetic testing for each of these conditions varies widely, with a causative variant identified in 75% of families with long QT syndrome and only 30% of families with Brugada syndrome (6). Interpretation of genetic testing results also can be complex due to insufficient information about each possible genetic variant. Consultation with an experienced inherited cardiac arrhythmia specialist and genetic counselor is strongly recommended if the athlete responds positively to this question. Cardiovascular Preparticipation Evaluation

Copyright © 2015 by the American College of Sports Medicine. Unauthorized reproduction of this article is prohibited.

4) Has anyone in your family received treatment for this condition, such as medications or a pacemaker/ defibrillator? Conditions such as long QT syndrome and CPVT are usually treated with medications such as beta-blockers. Patients with any of the inherited arrhythmias who have high-risk features may have received a defibrillator, which is often confused for a ‘‘pacemaker’’ by family members. A positive response with a treatment consistent with the disease in question increases the likelihood of an accurate family history. WHEN TO REFER Patients who are considering participating in competitive athletics and report a family history of inherited arrhythmic diseases in a first- or second-degree relative should be referred for evaluation by a cardiologist and genetic counselor familiar with the clinical presentation, diagnostic workup, genetics, and screening recommendations of these disease conditions. Athletes are usually evaluated with modified ECG, exercise tests, and possibly chemical challenges when the family history is positive. Since initial testing can result in false negative testing result, athletes often require ongoing evaluation based on the suspected arrhythmia disorder, age, and exercise intensity. Centers specializing in family-based care of patients with inherited cardiomyopathy are well situated to provide longitudinal follow-up and screening of other family members. Finally, genetic testing may play a role in screening families where a causative variant has been identified. The interpretation of this testing requires highly specialized knowledge of a very rapidly changing field and should be performed in consultation with an experienced cardiovascular geneticist and/or genetic counselor. CASE REPORTS Case Report 1 A 19-year-old male college basketball player presents for a PPE. He denies ever having palpitations, dizziness, lightheadedness, or syncope and has normal physical examination results. He recognized ‘‘long QT syndrome’’ and stated that he thought his mother was diagnosed with this in the hospital a few months back. The athlete was referred to a cardiologist who performed a lying and standing ECG where his corrected QT interval was within normal limits. The mother’s hospital records were obtained, and she had been treated with azithromycin for pneumonia. An ECG revealed a QTc of 490 ms, and she was diagnosed with acquired long QT. After being taken off the antibiotics, her ECG normalized. Although there may be some degree of underlying genetic susceptibility to acquired long QT syndrome, family members are currently not required to undergo screening. The athlete was allowed to play basketball and will not require routine ECG; he should have an ECG checked when and after taking QT-prolonging medications. Case Report 2 A 14-year-old Asian candidate for the girl’s badminton team presented for a PPE at the community center. She was very healthy and had no history of palpitations or syncope. www.acsm-csmr.org

Her physical examination result was normal. When asked about family history, she immediately recognized the Brugada syndrome. Her paternal uncle had been diagnosed with Brugada syndrome and had a defibrillator placed, but her family did not think that she was at risk because her father’s ECG was normal. She was referred to a specialized inherited arrhythmia clinic where her modified Brugada ECG was found to be normal. The genetic counselor tracked down genetic test results from her uncle that showed a variant in SCN5A with a high degree of confidence for pathogenicity. The athlete and her father tested positive for this pathogenic variant. The athlete and father were advised to avoid sodium channel-blocking medications, to control fevers with acetaminophen, and to avoid excessive heat. With a normal ECG and no history of syncope, she was considered at relatively low, but higher than the average athlete, risk of sudden death during athletic activity. She chose to continue playing badminton. An automatic external defibrillator (AED) was arranged for all her practices and games. Her family also opted to take basic life support classes and purchase an AED for the home. She will have yearly ECG and report any syncope immediately. References 1. Antzelevitch C, Brugada P, Borggrefe M, et al. Brugada syndrome: report of the second consensus conference: endorsed by the Heart Rhythm Society and the European Heart Rhythm Association. Circulation. 2005; 111:659Y70. 2. Froelicher V, Wagner G. Introduction to Symposium on J wave patterns and a syndrome. J Electrocardiography. 2013; 46:1Y3. 3. Schwartz PJ, Moss AJ, Vincent GM, Crampton RS. Diagnostic criteria for the long QT syndrome. An update. Circulation. 1993; 88:782Y4. 4. Schwartz PJ, Stramba-Badiale M, Crotti L, et al. Prevalence of the congenital long-QT syndrome. Circulation. 2009; 120:1761Y7. 5. Taggart NW, Haglund CM, Tester DJ, Ackerman MJ. Diagnostic miscues in congenital long-QT syndrome. Circulation. 2007; 115:2613Y20. 6. Tester DJ, Will ML, Haglund CM, Ackerman MJ. Compendium of cardiac channel mutations in 541 consecutive unrelated patients referred for long QT syndrome genetic testing. Heart Rhythm. 2005; 2:507Y17.

Marfan History in Athletes from Family History Section David Liang, MD, PhD

Question 9. Does anyone in your family have Marfan syndrome? Marfan syndrome is a heritable disease due to mutations in the fibrillin-1 gene that leads to aortic root aneurysms and mitral valve prolapse. Those afflicted are at risk for aortic dissection and/or rupture that may be precipitated by the increased hemodynamic stress of exercise. The overall population prevalence is thought to be 1 in 5,000 to 1 in 10,000. Inheritance is autosomal dominant with near 100% penetrance. Approximately 25% to 33% of cases will represent spontaneous mutations, so over half of those with Marfan syndrome can be identified with this simple question. The reliability of this question is limited by the accuracy of the Marfan syndrome diagnosis in the family member with the syndrome. It is worthwhile to obtain details upon which the diagnosis was made. If only musculoskeletal features were noted in the affected relative and there is no Current Sports Medicine Reports

Copyright © 2015 by the American College of Sports Medicine. Unauthorized reproduction of this article is prohibited.

341

Family History of Inherited Arrhythmic Disease from Family History Section.

Family History of Inherited Arrhythmic Disease from Family History Section. - PDF Download Free
64KB Sizes 0 Downloads 8 Views