[SCD-FORUM] EXPERTS ASK, EXPERTS ANSWER

[SCD Symposium]

Dr. Luciano Pereira from Paraguay asks

- The Commotio Cordis is an entity increasingly being diagnosed over  
the last few years. Since it is highly deadly and affects young  
sportsmen in most cases, cardioverter defibrillators and other  
reanimation devices availability should not be obligatory in public  
and private institutions devoted to sports?

Dr. Andres Perez Riera from Brazil answers

- Dear Luciano: Here Andrés Ricardo Pérez Riera from São Paulo  
Brazil.   Cardiac concussion,  commotio cordis, or nonpenetrating  
chest wall impact (traumatic blow to the chest wall causing VT/VF) is  
caused by a sudden, nonpenetrating, localized impact to the chest  
that is theorized to result in almost simultaneous SD from a  
disruption to the conductive system. Commotio cordis may lead to SCD  
due to the acute initiation of VF.  VF may result from sudden stretch  
during a vulnerable window, which is determined by repolarization  
inhomogeneity.  The detailed external/internal forensic examination  
of the body reveals no evidence of structural, pathologic, or  
histologic signs of trauma to the heart. A cardiac concussion is a  
rare and often overlooked cause of SD. This type of SD is typically  
seen among younger individuals participating in sports involving  
projectiles and, to a lesser degree, where collisions occur. Cardiac  
concussions are clinically, pathologically, and chemically different  
from a cardiac contusion1.

The main cause’s of SD among young athetes (<35 years old) are:

1) Hypertrophic cardiomyopathy (HCM) is the most common form of SD in  
young competitive athletes;

2)  Arrhythmogenic right ventricular dysplasia (ARVD);

3)   Anomalous coronary origins: White-Bland-Garlad syndrome and others;

4) Marfan syndrome;

5)     Premature coronary artery disease;

6)   Structurally normal heart (ion channel disorders.): SD with a  
structurally normal heart was the leading cause of death among female  
young recruits during military training2. These main entities are:  
congenital LQTS, the SQTS, BrS and CPVT.  These are pathologies with  
very different phenotypes and aetiologies, but which share a common  
final pathway in causing SD: amplification of spatial dispersion of  
repolarization in the form of TDR(3).

7)   Inflammatory myocardial diseases: Myocarditis

8) Commotio cordis.

Analyze the presence of myocardial damage in relation to official  
boxing matches. Low-energy chest wall impact could be responsible for  
SCD h, i.e. commotio cordis. As boxing is a traumatic sport in which  
thoracic hits usually occur, it seems interesting to know if there  
are any significant cardiac changes during official bouts. Fifteen  
amateur boxers, participating in the semifinals of the Italian  
Championship were investigated by Bianco et al.

A standard ECG before, immediately after, 1 hour and 12 hours after  
the match were obtained from each athlete to analyze:

1)      Atrio-ventricular conduction;

2)      QRS axis and duration;

3)      Ventricular repolarization.

A blood sample was also obtained before and 12 hours after the match  
for analysis of total-creatin-phosphokinase, myoglobin, and T- 
troponin. After the fight, the following significant changes were  
encountered:

1)  Higher QRS voltages;

2) Lowering of J-point and ST segment in lateral leads;

3) Higher ST-slope;

4) Lower T-wave amplitude;

5) Shorter T-wave peak time, and

6) Shorter QT interval.

When the last 2 parameters were corrected for heart rate, no  
differences were observed for QTc, while T-wave peak time  
significantly increased. All these changes persisted until one hour  
after the match. Moreover, 3/15 boxers (20 %) showed marked  
ventricular repolarization anomalies in lateral leads after the  
contest, persisting for 12 hours in one case. However, no athlete had  
clinical and humoral signs of myocardial damage following the match.  
It was concluded that no clinical and humoral signs of myocardial  
damage were found after amateur boxing matches, although ventricular  
repolarization abnormalities can be found on ECG in 20 % of boxers,  
probably due to sympathetic hyper-activity related to the agonistic  
event(4).



References
1) Koehler SA, Shakir A, Ladham S, et. al. Cardiac concussion:  
definition, differential diagnosis, and cases presentation and the  
legal ramification of a misdiagnosis. Am J Forensic Med Pathol.  
2004;25:205-208.
2) Eckart RE, Scoville SL, Shry EA, Potter RN, Tedrow U. Causes of  
sudden death in young female military recruits.Am J Cardiol. 2006;  
97:1756-1758.
3) Antzelevich C, Oliva A. Amplificaion of spatial dispersion of  
repolarization underlies sudden cardiac death associated with  
catecholaminergic  J Intern Med. 2006;259:48-58
4) Bianco M, Colella F, Pannozzo A, Oradei A, et al. Boxing and  
"commotio cordis": ECG and humoral study. Int J Sports Med.  
2005;26:151-157.

All the for all

Andrés Ricardo Pérez Riera MD
  Chief of Electro-Vectocardiology Sector of the Discipline of  
Cardiology,
  ABC Faculty of Medicine (FMABC), Foundation of ABC (FUABC)
  – Santo André – São Paulo – Brazil.
  Sebastião Afonso 885 Jardim Miriam SP Brazil
  Zip Code: 04417-100
  riera at uol.com.br

--
Dr. Sergio Dubner
President of Scientific Committee

Dr. Edgardo Schapachnik
President of Steering Committee




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