Cardiac arrest during marathons are rare, but possible

Millions of Americans participate in long-distance running events. The marathon distance (26.2 miles) and the half-marathon (13.1 miles) have become increasingly popular. It is because of the extreme physical demands of these competitions that the occasional report of sudden death during an event is not surprising.

The human heart consists of four chambers that contract and expand in sequence to pump blood throughout the vascular system. In order to do this, the heart has a carefully synchronized electrical network that must fire signals in a rhythmic manner.

The muscular heart chambers have thick walls that allow for the maximum volume of blood to be ejected with each beat. Aerobic training reduces the amount of effort necessary for the heart to function.

A recent study looked at the incidence and outcomes of cardiac arrest associated with marathon and half-marathon events from January 2000 to May 2010. The number of participants steadily grew from 1 million in 2000 to 2 million in 2010.

Of the 11 million people studied over the 10-year span, only 59 suffered cardiac arrest during a race. Cardiac arrest was most common in males who participated in full marathons as opposed to half-marathons. Men were also most likely to die from the arrest and are clearly more susceptible to exertional cardiac arrest.

Surprisingly, the most common cause of arrest was not due to blockage of coronary arteries but an oversized left ventricle. The increased size (hypertrophy) eventually blocks the outflow of blood from the heart.

Cardiac hypertrophy is most common in younger athletes and associated with poor outcome.

The rate of cardiac arrest should in no way discourage participation in long-distance athletic events. Instead, it should alert athletes to the need for proper pre-participation physical examinations.

Giants' Mark Herzlich overcomes bone cancer

Inspirational comeback stories abound in the world of sports. This year’s NFL season is no exception, such as the come-from-behind, underdog victories by the Denver Broncos, led by Tim Tebow.

One story that bears noting is the return of Mark Herzlich to the sport many thought was part of his past and not his future.

Herzlich, a 24-year-old linebacker for the New York Giants, was diagnosed with Ewing’s sarcoma, a form of bone cancer, while playing for Boston College. His treatment included chemotherapy, radiation therapy and excision of the tumor that involved the largest bone in the human body, the femur. A titanium rod reinforced the bone shaft.

A two-year course of physical therapy and intense training followed. After being invited to try out for the New York Giants, he accomplished something many thought was impossible: He made the team.

Ewing’s sarcoma is a malignant tumor that typically is seen in children and young adults. It generally appears in the long bones of the body.

The most common presenting symptom is intense bone pain. Unfortunately, in approximately one-third of patients, the tumor already has spread to the lungs and other bones at the time of diagnosis.

Treatment of Ewing’s sarcoma includes aggressive chemotherapy and radiation therapy that is focused on the tumor site. Surgical excision of the tumor follows.

Dr. Dinesh Kapur, an oncologist and director of cancer services at The William W. Backus Hospital, isn’t surprised by Herzlich’s recovery.

“Early detection, combined with the multimodality approach of chemotherapy, radiation and surgery, has dramatically improved survival from Ewing’s sarcoma,” Kapur said.

Herzlich’s return to the highest level of professional sports not only required a combination of modern medical therapies, but an unwavering spirit and commitment to succeed.

Celtics player saved from aortic aneurysm

Amidst the confusion of ending the NBA lockout and hurriedly beginning a shortened season, a young life was saved.

Jeff Green, a 25-year-old forward, had signed a one-year, $9 million contract to play for the Boston Celtics. During a routine preseason physical examination, he was diagnosed with an aortic aneurysm. Instead of heading over to the practice court, Green was headed to the operating room.

The aorta is the largest artery in the human body. It provides the main passageway for richly oxygenated blood to vital organs. The aorta is divided into two main sections:

• The thoracic aorta leads blood from the heart and downward through the chest cavity.
• The abdominal aorta continues into the abdomen feeding branches to the kidneys, liver, spleen and intestines.

An aneurysm is an abnormal enlargement of a blood vessel. It results from a weakening of the supporting tissue that provides a firm lining in an artery. Under constant pressure, the weakened area will enlarge and cause the artery to dilate and eventually rupture. This results in profuse life-threatening hemorrhage.

Aortic aneurysms can be repaired by cutting out the affected section of aorta and replacing it with a synthetic segment. Another approach is an endovascular repair. In this procedure, a new lining is inserted in the weakened area via a catheter through an artery in the groin.

Aneurysms are typically associated with high blood pressure, elevated cholesterol levels, obesity and smoking. All of these potential causes are not typically associated with professional athletes.

Green’s aneurysm will be repaired and he is expected to return to the NBA next season.

Jeff Green’s circumstance should serve as a reminder of the importance to have annual physicals performed by a physician even if you are young and in excellent health.