Maron BJ, Gohman TE, Kyle SB, Estes III NAM, Link MS. Clinical Profile and Spectrum of Commotio Cordis. JAMA. 2002;287(9):1142-1146. doi:10.1001/jama.287.9.1142
Author Affiliations: Cardiovascular Research Division, Minneapolis Heart Institute Foundation, Minneapolis, Minn (Dr Maron and Mr Gohman); Cardiac Arrhythmia Center, New England Medical Center and Tufts University School of Medicine, Boston, Mass (Drs Link and Estes); and United States Consumer Product Safety Commission, Washington, DC (Dr Kyle).
Context Although blunt, nonpenetrating chest blows causing sudden cardiac death
(commotio cordis) are often associated with competitive sports, dangers implicit
in such blows can extend into many other life activities.
Objective To describe the comprehensive spectrum of commotio cordis events.
Design and Setting Analysis of confirmed cases from the general community assembled in
the US Commotio Cordis Registry occurring up to September 1, 2001.
Main Outcome Measure Commotio cordis event.
Results Of 128 confirmed cases, 122 (95%) were in males and the mean (SD) age
was 13.6 (8.2) years (median, 14 years; range, 3 months to 45 years); only
28 (22%) cases were aged 18 years or older. Commotio cordis events occurred
most commonly during organized sporting events (79 [62%]), such as baseball,
but 49 (38%) occurred as part of daily routine and recreational activities.
Fatal blows were inflicted with a wide range of velocities but often occurred
inadvertently and under circumstances not usually associated with risk for
sudden death in informal settings near the home or playground. Twenty-two
(28%) participants were wearing commercially available chest barriers, including
7 in whom the projectile made direct contact with protective padding (baseball
catchers and lacrosse/hockey goalies), and 2 in whom the projectile was a
baseball specifically designed to reduce risk. Only 21 (16%) individuals survived
their event, with particularly prompt cardiopulmonary resuscitation/defibrillation
(most commonly reversing ventricular fibrillation) the only identifiable factor
associated with a favorable outcome.
Conclusions The expanded spectrum of commotio cordis illustrates the potential dangers
implicit in striking the chest, regardless of the intent or force of the blow.
These findings also suggest that the safety of young athletes will be enhanced
by developing more effective preventive strategies (such as chest wall barriers)
to achieve protection from ventricular fibrillation following precordial blows.
Sudden and unexpected deaths of young individuals are highly visible
and emotionally charged events.1- 3
These deaths are frequently the consequence of unsuspected congenital cardiovascular
in trained athletes. However, organized sports are subject to another risk
for sudden death (ie, blunt, nonpenetrating, and usually innocent-appearing
chest blows, commotio cordis).7- 12
However, the spectrum of commotio cordis is diverse, and the risks considerably
more pervasive. In this study we characterize more completely the evolving
and heterogeneous clinical profile of chest blows causing sudden death.
The 128 cases consecutively entered into the US Commotio Cordis Registry,
Minneapolis, Minn, as of September 1, 2001, constitute the present series.
Fourteen (11%) of these cases were identified from news media and Internet
accounts, 46 (36%) from records of the US Consumer Product Safety Commission,
and 68 (53%) from direct submission to the registry by medical examiners,
other medical or sports-related sources, and interested nonmedical parties.
Each case fulfilled the following inclusion criteria: (1) a witnessed
event of a blunt, nonpenetrating blow to the chest immediately preceded cardiovascular
collapse; (2) detailed documentation of the circumstances from available newspaper
articles, police reports, and telephone interviews with family members or
other witnesses; (3) absence of structural damage to the sternum, ribs, and
heart itself; and (4) absence of any underlying cardiovascular abnormalities.
Autopsies were performed in 82 of the 107 fatal cases; 23 of the other
25 cases occurred in ball sports (baseball, softball, cricket, hockey, and
lacrosse) in circumstances similar or identical to other registry cases for
which autopsy data were available. In 3 cases, real-time videotape of the
event was available for analysis. Of the 128 cases, 65 (51%) occurred from
1995 through 2001, 28 (22%) from 1985 through 1994, and 35 (27%) prior to
1985. Selected data from 70 cases have been included in prior reports.7,13
Ages of the 128 cases ranged from 3 months to 45 years (mean [SD], 13.6
[8.2] years; median, 14 years); 56 (44%) were 12 years or younger while only
28 (22%) were 18 years or older (Figure 1); 122 (95%) were male.
Competitive Sports. At the time of their commotio cordis event, 79 participants (62%) were
engaged in organized competitive sports at the youth (n = 37), high school
or junior high school (n = 30), college (n = 7), and professional (n = 5)
levels (Figure 2). Although 11 sports
are represented, 46 (58%) of these commotio cordis events occurred during
either baseball or softball games and 13 (16%) at ice hockey games (Figure 2).
Routine Daily and Recreational Sporting Activities. Forty-nine other commotio cordis events (38%) occurred during a variety
of innocent-appearing and recreational activities in informal and largely
unstructured settings, such as in the backyard, playground, or neighborhood
school yard or while participating in a variety of daily activities and circumstances
unrelated to sports and often under other extraordinary circumstances (Table 1).
Eighteen of the 49 events involved either bodily contact or contact
with implements regarded as toys (and were not athletic equipment), such as
a hollow plastic bat a 13-year-old boy flung 15 feet that inadvertently struck
the chest of his 2-year-old sister. A 5-year-old boy died instantaneously
after being struck in the chest by a circular plastic sledding saucer. Two
adolescent boys died suddenly after receiving sharp but light chest blows
from friends during a playful "shadow" boxing match that involved a closed
or open fist (ie, with a jab or push). In 2 other unusual cases, a 23-year-old
man fatally struck his friend in the chest with a closed fist, as a mutually
agreed on remedy for hiccups, and a 2-year-old girl was incidentally struck
in the chest by the head of her pet dog. The oldest victim in this series
was a 44-year-old teacher, who died when she was inadvertently struck in the
chest by an elbow while intervening during a scuffle between 2 teen-aged female
In 8 of these 18 cases, relatively modest chest blows caused death when
an adult struck either a child as part of parent-child discipline (ages 3
months to 11 years) or an adult struck another adult in gang-related rituals.
Seven of these 8 cases triggered a homicide investigation with charges of
first-degree murder (1 prosecutor sought the death penalty); each perpetrator
was convicted of murder, manslaughter, or reckless homicide.14
Projectiles. Of 107 commotio cordis events that were regarded as part of competitive
or other sporting activities, 87 (81%) involved a blunt precordial blow from
a projectile (which served as a standard implement of the game), or another
object propelled against a stationary chest wall, resulting in relatively
localized contact, during organized or recreational play (Table 1). Projectiles were most commonly baseballs (n = 53), including
50 of apparent regulation design, 1 hard rubber ball, and 2 others marketed
commercially as reduced-injury, softer-than-normal (so-called safety or training)
balls, made largely of rubber of various textures contained in a synthetic
Other projectiles included 14 softballs, as well as 10 hockey pucks
and 5 lacrosse balls, both of which are made of hard rubber. With the exception
of 1 air-filled soccer ball, each projectile that resulted in commotio cordis
had a hard solid core. Six of these 87 cases were innocent bystanders inadvertently
struck in the chest by a thrown or batted ball, including spectators or players
observing the game from the dug-out or bull pen.
Scenarios Involving Projectiles. Individuals struck in the chest by baseballs (including T-balls) or
softballs were involved in a variety of scenarios. In 23 instances, balls
struck young children in the chest at relatively close range, either batted
or thrown by friends, parents, or siblings at speeds not unusual for the circumstances.
For example, 1 fatal incident occurred on a family outing, when a soft baseball
gently tossed underhand by a father to 6-year-old son deflected off the heal
of his glove striking the child's chest.
In competitive circumstances, 13 cases were batters (or in 1 case an
umpire without a chest protector) who were struck by a pitched ball; body
size and athletic ability of the pitcher and the speed of the ball were considered
unremarkable for the game and only 1 pitcher was an adult. Velocities of the
pitched ball were estimated to be 48 to 80 km/h (30-50 mph) from distances
of about 12 to 18 m (40-60 ft). Eleven other baseball players were pitchers
struck in the chest by batted balls over similar distances. Twenty other players,
including base runners and catchers, were hit in the chest at distances of
up to 30 m (100 ft) by batted or thrown balls.
Ten ice hockey–related events resulted from chest blows inflicted
by a high-velocity slap-shot at relatively close range, involving players
stationed in defensive positions, including 1 goalie. Five other events occurring
during a lacrosse match, included 3 goalies who were struck by high-velocity
shots and 2 others by errant field passes.
Nonprojectile Blows. During competitive or other sporting activities, 20 individuals (19%)
received chest blows delivered by physical contact with another person—ie,
by a fist, shoulder, forearm, elbow, knee, foot, or head or by the heel of
an ice hockey stick (Table 1).
Examples included bodily collisions in rugby, hockey, and soccer; between
baseball players in pursuit of a batted ball; blocking and tackling in football;
or from karate blows.
Of the 128 individuals experiencing commotio cordis, 107 (84%) died
as a consequence of their event, and 21 (16%) have survived as of April 2001
over a follow-up period of 1 to 20 years (mean [SD], 7  years). Fifteen
survivors achieved complete physical recovery, and 6 have mild to moderate
residual neurologic disability or cardiac impairment (manifested by reduced
left ventricular ejection fraction). Of the 21 survivors, 19 had resuscitative
measures instituted for cardiac arrest, including 2 particularly fortuitous
baseball-related events in which a 13-year-old batter and a 38-year-old umpire
who was not wearing a chest protector were each struck in the chest by a pitched
ball and had ventricular fibrillation terminated by an automated external
defibrillator. The 2 others collapsed with apnea, loss of consciousness, and
cyanosis but responded spontaneously without resuscitation, including a hockey
player struck by a slap-shot during the Stanley Cup playoffs; these events
were judged likely to be examples of aborted commotio cordis.
Cardiopulmonary resuscitation was known to have been performed by bystanders
in cases of 106 individuals, including defibrillation in 41; most of these
events involved trained personnel such as nurses, fire-fighters, physicians,
or emergency medical technicians. Of 68 events for which resuscitative measures
were known to have been instituted in a timely fashion (estimated <3 minutes),
17 (25%) survived. In contrast, of the other 38 cases in which resuscitation
was substantially delayed (>3 minutes), there was only 1 survivor (3%, P = .007 by χ2 test). For 1 survivor, the
time interval from collapse to resuscitation could not be determined. Fifty-one
of the 68 who received apparently prompt resuscitation nevertheless died.
Data from the initial electrocardiogram conducted after collapse (recorded
in the emergency department or by emergency medical technicians) could be
analyzed in 82 cases. The arrhythmias included 33 with ventricular fibrillation
(VF), 3 with ventricular tachycardia, 3 with bradyarrhythmias, 2 with idioventricular
rhythm, 1 with complete heart block, and 40 with asystole, which was unlikely
to be the initial rhythm after impact. These rhythms were recorded at the
scene of the event in 42 cases, and in the other 29 cases, they were recorded
in the emergency department. Eleven cases could not be resolved with certainty.
Ventricular tachycardia/fibrillation were identified in 26 nonsurvivors and
Of the 79 individuals participating in organized, competitive athletic
activities, 22 (28%) were wearing standard, commercially available chest barriers,
generally regarded as providing protection to the chest wall against the consequences
of direct blows. These included 12 hockey (including 2 goalies), 5 football,
3 lacrosse (all goalies during 2000 and 2001), and 2 baseball (both catchers)
Analysis of the hockey-related events suggests a scenario for 8 cases
in which it is likely that the puck probably struck the chest wall directly
due to the angle of the shot, which appeared to circumvent the position of
the standard shoulder-chest protector. Alternatively, when the defensive player
instinctively raised (or extended) his arms to obstruct a slap-shot, the chest
barrier probably migrated cephalad, thereby allowing the puck to directly
strike the unprotected precordium.7 Similarly,
for each of the 5 football players wearing standard equipment, design of the
chest-shoulder padding was judged unlikely to have protected the precordium
from the blow.
In 7 other athletes with commotio cordis (3 lacrosse goalies, 2 baseball
catchers, 2 hockey goalies), all of whom were equipped with commercially available
chest barriers of standard design, the projectiles that caused the commotio
cordis event were judged to have probably struck the chest protector directly
(but not the chest), nevertheless resulting in a commotio cordis event. Each
chest barrier was made largely from rubberlike closed or open-cell polymer
foam covered by fabric or hard shell.
Blunt, nonpenetrating chest blows, often innocent in appearance and
causing virtually instantaneous sudden death (commotio cordis) most commonly
in young males, have been the subject of increasing attention.7- 9,14
Although earlier reports were limited largely to organized and competitive
sports, particularly baseball,7,10,15,16
our continued interest in this devastating phenomenon with its increased visibility
and public exposure during the past 6 years has permitted the systematic assembly
of a large cohort. Even though the data from this registry do not allow determination
of the prevalence or incidence of commotio cordis, the cases included demonstrate
a diverse spectrum of events, including many occurring in the broader context
of daily life unrelated to sports. Indeed, many cases of commotio cordis resulted
from innocent and often unintentional chest blows occurring at home or at
school, including several under particularly unusual circumstances that could
not be regarded (even remotely) as life-threatening.
Some such examples include chest blows delivered by punitive parent-child
interaction; as an ill-advised effort to terminate hiccups; and from the head
of a pet dog as it greeted a small child, a snowball, a rebound motion of
a playground swing carriage, and a hollow plastic toy bat flung during a child's
game; or a blow during a friendly shadow-boxing match. Such examples underscore
the critical message that any chest blow, even when modest or innocent and
delivered unintentionally, can be life-threatening.
The uncommon occurrence of commotio cordis is largely explained by its
mechanism, which requires the exquisite confluence of several determinants
such as location of the blow directly over the heart7,17
and precise timing to the vulnerable phase of repolarization (just prior to
T-wave peak).17- 20
Young children with narrow and underdeveloped chest cages also appear most
susceptible to commotio cordis, as evidenced by the average age of 14 years
in this cohort (one third of whom were 10 years or younger), although adults
comprised almost one fourth of the study group.
Commotio cordis impacts are typically of low-energy and velocity7,13,17- 20
although the wide range of velocities is evidenced by some hockey puck and
lacrosse ball blows with estimated speeds up to 144 km/h (90 mph). Solid core
projectiles appear much more likely to trigger commotio cordis since only
1 registry case involved an air-filled ball (ie, soccer). It is likely that
projectiles with a nonsolid core are capable of absorbing much more of the
impact energy by their own collapse without transmitting that momentum to
the chest wall.
Sports-related commotio cordis deaths have triggered considerable interest
in chest barriers to protect young sports participants from catastrophic precordial
blows. Indeed, these registry data provide an opportunity to gain insights
into the adequacy of chest barriers by analyzing a subset of 22 cases for
whom chest protectors failed to prevent VF. In many ice hockey and football-related
deaths, it was unlikely that commercially available chest or shoulder padding
had actually covered the precordium at the time of impact. For example, standard
gear in football does not extend inferiorly to cover most of the chest cage;
shoulder and chest padding in hockey may cover the precordium but can move
upward when the arms are raised, thereby leaving the critical central area
of the anterior chest unprotected and vulnerable.7
Of note, in 7 cases reported herein, it appeared that a projectile struck
the chest protector directly. These cases included baseball catchers and lacrosse
goalies, suggesting that the standard commercially available chest barriers,
made from relatively soft foam padding, may have been inadequate to abort
or blunt sufficiently the instantaneous transmission of mechanical energy
to the heart that occurs in commotio cordis; this may have occurred due to
local absorption rather than the distribution of force.17- 20
Indeed, because of the current level of uncertainty regarding the material
composition of chest barriers that would be truly protective against chest
blow–induced VF, the American Academy of Pediatrics has not recommended
routine use of chest protectors for youth baseball players other than catchers.21
We have previously demonstrated in an experimental model of commotio
cordis that reduced injury (safety) baseballs decreased (but did not abolish)
risk for VF with 48 km/h (30 mph) precordial impacts.18
However, 2 of the deaths discussed herein were associated with balls specifically
marketed for their safety design as softer-than-normal; much of the core was
made from rubber of varying hardness, in contrast to the tightly-wound nylon
or wool yarn and cork (or rubber) that constitutes a regulation baseball.
Therefore, when cases in this series that are associated with chest barriers
that proved to be inadequate are combined with those involving reduced-risk
balls, 24 children in this registry died despite the perception that they
were probably protected from serious injury by commercially available safety
products. Although chest barriers and safety balls may reduce risk, it is
apparent that these devices do not achieve absolute protection from commotio
cordis and may only provide a false sense of security. This emphasizes the
necessity of designing chest protectors that reliably cover the precordium
under all circumstances and have a high level of efficacy for preventing VF
following a precordial blow.
Only about 15% of commotio cordis cases in this series survived their
events22,23 with most achieving
normal neurologic and cardiac function. These data suggest that particularly
prompt cardiopulmonary resuscitation or defibrillation is a major determinant
of surviving a commotio cordis event. Resuscitation efforts in 2 survivors
demonstrated the importance of defibrillation (with automated external defibrillators)
in terminating potentially lethal ventricular tachyarrhythmias and restoring
sinus rhythm at the scene.
For cases in which electrocardiographic data were available, ventricular
tachyarrhythmia was the substrate most commonly responsible for chest blow–induced
sudden death, as previously demonstrated in our experimental animal model.17- 20,24
Such ventricular tachyarrhythmias were commonly identified at the scene and
in the emergency department and were also the shockable rhythms in those cases
in which survival was due to the availability and use of an automated external
defribillator. On the other hand, when cardiopulmonary support was substantially
delayed, often due to the failure of bystanders to fully appreciate the nature
of the collapse, survival rarely occurred. Nevertheless, prompt resuscitation
for commotio cordis did not guarantee survival, underscoring the serious nature
of chest impact–induced VF, even in the absence of underlying structural
In conclusion, commotio cordis occurs in the setting of sporting events
as well as in a variety of circumstances that are part of daily living and
unrelated to athletic activities. Our observations emphasize the dangers implicit
in striking the chest sharply under any condition, including light or inadvertent
blows. Prevention of these catastrophes will be enhanced by greater education
and awareness about commotio cordis and its pathophysiology, within both the
lay and medical communities. Continued reports of these tragic events during
sports emphasize the importance of more timely resuscitative efforts, including
access to automated external defribillators,24
as well as developing preventive strategies including the design of effective