With the sudden unexpected death of Anna Nicole Smith on February 8th at age 39, the media is furiously attempting to determine what might have been her cause of death. While foul play would make the most sensationalist headlines, often sudden death in the young is attributible to cardiovascular causes.
At this time, we have been told that “prescription drugs” were found in her room, but no pills were found in her stomach at autopsy. It is a useful exercise at times like this to consider the differential diagnosis of sudden death in young women. Although certain drugs, like tricyclic antidepressants, could cause abnormal heart rhythms, many, many other drugs can cause fatal heart rhythms as well. But what if Anna Nicole’s toxicology screen comes up negative? What other causes of sudden death can occur in the young?
Although neurologic causes may occur, like a ruptured cerebral aneurism (blood bessel in the brain), by far and away, cardiovascular causes are the most prevalent cause of sudden death in the young. It was interesting to me that the cardiac examination was not mentioned in the press releases so far. Some cardiac causes of sudden death in the young are outlined below:
As a whole, these are disorders of the heart muscle itself.
Weakening of the heart muscle that occurs in the last month of pregnancy or up to five months after pregnancy. It usually is more common in women with more than one child, and its cause is unknown.
Idiopathic Dilated Cardiomyopathy
A dilated, weakened heart not caused by occlusions of the blood vessels of the heart. Most often the cause is unknown, but viral causes are often blamed. Heart failure manifested by swollen legs, shortness of breath with exertion, cough when reclining is a common symptom, but weakened hearts can also lead to abnormal heart rhythms that can lead to sudden cardiac arrest. Myocarditis, or inflammation of the heart, is a common cause of dilated cardiomyopathy, and is often preceded by flu-like symptoms.
An inherited disorder of heart muscle organization that causes the heart muscle to become thickened and stiff, leading to either a failure of the heart to relax so it can fill with blood, or causing obstruction to blood flow as blood leaves the heart.
Arrhythmogenic Right Ventricular Dysplasia
An inherited disorder that causes fatty deposits to occur within the heart muscle itself and leads to abnormal heart rhythms that can be fatal.
Coronary Artery Disease
Myocardial Infarction (Heart Attack)
Although uncommon in the young, certain types of lipid disorders could contribute to the development of premature coronary disease.
Long QT Syndrome
A genetic disorder of the major electrolyte (sodium and potassium) channels of the heart which can precipitate sudden unexpected life-threatening arrhythmias.
Congenital Abnormalities of Cardiac Anatomy
Congenital Anomalous Coronary Artery
Abnormal blood vessels that supply the heart can compromise blood flow to the heart, resulting in abnormal heart rhythms or a heart attack.
Unrecognized Valvular and Congenital Heart Defects
These are usually identified in children, but can be unrecognized
Connective Tissue Disease effecting the Major Blood Vessels
Marfan’s Syndrome/Ehler-Danlos Syndrome
These genetic abnormalities of the connective tissue that makes up the great vessels (and to some extent the heart) can lead to sudden rupture of these vessels and rapid death.
Blood clots to the lungs can obstruct blood flow to the heart and result in death. Women who smoke and are on birth control pills can be particularly susceptible to this problem.
Conduction System Disorders
Wolff-Parkinson White Syndrome
Abnormalities of the heart’s conduction system can result in the development of very rapid heart rhythms that, in rare instances, can be fatal. Wolff-Parkinson-White Syndrome is caused by an abnormal muscle fiber that short-circuits the normally insulated valve rings that separate the upper from lower chambers of the heart called an accessory pathway. This pathway permits electricity to pass in a circular fashion from the upper chambers to the lower chambers and back again extremely rapidly. Rhythms that are very rapid may limit the time for the heart to fill with blood, leading to loss of consciousness in rare cases.
While this list may not be complete, it serves as a useful reminder of the complexities of the heart that must be functioning properly to maintain life.