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Ventricular arrhythmia is a condition in which the normal, regular beating of the ventricular chambers of the heart is interrupted by irregularities in the pattern of contraction. Excessively fast, slow, or unstable ventricular contraction is not conducive to proper circulatory function and must be controlled. Amiodarone is an anti-arrhythmic drug that has been used for almost 30 years in the treatment of this condition; relatively serious side effects delayed the release of this drug in the United States until 1984, at which time it was approved only for the treatment of arrhythmia that was refractory (unresponsive) to less toxic drugs. A case is reported of a 29-year-old woman with a long history of severe ventricular arrhythmia that did not respond to first-line anti-arrhythmic medications (beta blockers, quinidine, procainamide, and tocainide), requiring her to rely on amiodarone for symptomatic relief. During the course of treatment, the patient became pregnant. She chose to continue the pregnancy as well as the amiodarone treatment, and at 38 weeks gestation gave birth to a female infant. Physical examination of the child did not reveal any organ abnormalities, but she was below the 10th percentile in body weight and was classified as small for gestational age. This categorization, although relatively benign, has a worse prognosis than normal weight for childhood illness and mortality. Five months after delivering this infant, the patient became pregnant again, and gave birth at 35.5 weeks (i.e., prematurely) to a male infant of normal body weight. Again, physical examination of the child revealed no abnormalities. At no time during either of the pregnancies or following the births did either the mother or the children exhibit any evidence of thyroid dysfunction, a relatively common adverse side effect of amiodarone treatment. In previously reported cases of neonatal complications (spontaneous abortion, death, heart murmur, etc.), thyroid dysfunction was implicated. Amiodarone treatment during pregnancy may, in the presence of normal thyroid function, not be linked with serious neonatal difficulties. (Consumer Summary produced by Reliance Medical Information, Inc.)

People who recover from cardiac arrest are at risk of suffering a recurrent episode. A subset of this group (60 to 80 percent) exhibits abnormalities in heart function during electrocardiogram (ECG) testing; these patients respond well to medication that alleviates the abnormalities. This improvement appears to prevent recurrence of cardiac arrest. The remaining 20 to 40 percent of patients show no abnormalities during ECG testing; this group is thought to be at a particularly high risk for sudden cardiac death. Seventy-one survivors of a single episode of cardiac arrest were evaluated. During testing, 26 of these patients had no inducible ECG abnormalities, such as ventricular tachycardia (abnormally rapid patterns of contraction of the ventricle). After a 16-month follow-up, 11 of the 26 patients suffered recurrent cardiac arrest, and 10 of these patients died. Analysis of the clinical data pertaining to these patients revealed that several variables were more likely to be associated with recurrent cardiac arrest. Among the 11 patients who suffered a recurrence, 55 percent had dilated cardiomyopathy (a defect in the functioning of the heart muscle), and 64 percent experienced premature ventricular contractions. Twenty-four-hour ambulatory ECG-guided therapy (wearing a portable ECG machine) did not improve the survival rate for these patients. Further studies are needed to determine the optimal treatment strategy for this high-risk group of patients. (Consumer Summary produced by Reliance Medical Information, Inc.)

Ventricular aneurysms (ballooning of the walls of the lower heart chamber) have many causes, with coronary artery disease being the cause in 75 percent of cases. Infrequently, no cause can be found; these are idiopathic cases. A case is reported of a 56-year-old woman with three idiopathic left ventricular aneurysms. For four years, prior to hospitalization, the patient had dyspnea (shortness of breath) on exertion, which was diagnosed as mild congestive heart failure. She had no other history of disorders which could contribute to ventricular tachycardia (rapid heartbeat), the symptom for which she was hospitalized. Her heart rate was 200 beats per minute (bpm), while the normal rate is 72 bpm. The initial chest X-ray showed no abnormal bulges indicative of aneurysms. Invasive imaging techniques were needed to reveal the aneurysms. Ventricular tachycardia was not responsive to drugs, and a device was implanted to restore normal heart rhythm. All previously reported cases of ventricular aneurysms were of single aneurysms, all of which were associated with arrhythmias. The study suggests this is a case of true idiopathic disease, as little or no evidence was found for known causes such as coronary artery disease, thrombi (clots), Chagas disease (a parasitic infection), or syphilis. (Consumer Summary produced by Reliance Medical Information, Inc.)

Atrial fibrillation is the most common cardiac arrhythmia and leads to an increased risk of stroke, heart failure, and death in affected patients. Despite a plethora of treatment modalities and many advances in our understanding of atrial fibrillation mechanisms and natural history, the management of patients with atrial fibrillation continues to pose many challenges. This review provides a concise discussion on the role of various pharmacologic and nonpharmacologic therapies that are currently being utilized. The recommendations are evidence based and take into account the findings of many recently conducted outcome trials in atrial fibrillation. [ABSTRACT FROM AUTHOR]

We report the case of a patient who developed a life-threatening polymorphous ventricular tachycardia [PVT] after six weeks of treatment with amiodarone. The Q-T interval was markedly prolonged at 0.86 second. The drug induction of PVT was strongly suggested by the fact that PVT resolved four days after withdrawal of amiodarone when the Q-T interval had shortened to 0.60 second; the arrhythmia has not recurred in the nine months of follow-up since then. Amiodarone, though a very effective antiarrhythmic agent, may induce serious PVT. [ABSTRACT FROM AUTHOR]