Sudden death in hemochromatosis after closed-chest catheter ablation of the atrioventricular junction

Atrioventricular junction ablation and pacemaker implantation for heart failure associated with atrial fibrillation: potential issues and therapies in the setting of acute heart failure syndrome

Atrial fibrillation is the most common arrhythmia and is especially clinically important in patients with heart failure. Prolonged atrial fibrillation with high ventricular rate response may lead to development or worsening of left ventricular function. If adequate heart rate control cannot be obtained medically, often patients will undergo pacemaker implant and catheter ablation of the atrioventricular junction. This intervention can have profound effects on the course of heart failure. This article reviews the technique, complications, outcome data, and alternatives to this management strategy. The potential role of this therapeutic modality in those hospitalized with acute heart failure syndromes is discussed.

Sudden cardiac death in infiltrative cardiomyopathies: sarcoidosis, scleroderma, amyloidosis, hemachromatosis

Sarcoidosis, scleroderma, amyloidosis, and hemachromatosis are systemic infiltrative disorders that commonly affect the heart. Owing to their potential for diffuse organ involvement, these diseases may present with myriad clinical manifestations. Conduction system abnormalities are common, and each of these disorders has been associated with sudden cardiac death. In this review, we summarize the epidemiology, clinical features, diagnosis, and treatment of each of these entities. We place special emphasis on existing literature as it pertains to risk stratification and therapy aimed at the prevention of sudden cardiac death in these infiltrative cardiomyopathies.

Predictors of in-hospital mortality after DC catheter ablation of atrioventricular junction. Results of a prospective, international, multicenter study

BACKGROUND

The Catheter Ablation Registry was the first international, multicenter, prospective study of the safety and efficacy of catheter ablation.

METHODS AND RESULTS

From August 1987 through March 1990, the study comprised 136 patients in whom only DC energy was used in attempted production of third-degree atrioventricular block to treat uncontrollable supraventricular tachycardias. Eight patients died during hospitalization for ablation. In seven (5.1%), the ablation may have contributed to their deaths. Causes of death included ventricular fibrillation (five patients, three with polymorphic ventricular tachycardia), progressive heart failure (one patient), and respiratory failure (two patients, one dying after resuscitation from ventricular fibrillation). Compared with survivors, patients who died were more likely to have had prior aborted sudden death (38% versus 2%, p less than 0.05), congestive heart failure (88% versus 22%, p less than 0.001), cardiomyopathy (50% versus 16%, p less than 0.05), lower baseline systolic blood pressure (106 versus 138 mm Hg, p less than 0.001), prolonged baseline and postablation corrected QT interval (p less than 0.01), and markedly reduced ejection fraction (27% versus 52%, p less than 0.001). Ablation successfully produced third-degree atrioventricular block in 88% of the patients who died and in 83% of survivors.

CONCLUSIONS

Catheter ablation of the atrioventricular junction with DC energy carries a significant, previously unrecognized risk of death (5.1%), particularly from lethal arrhythmias, when applied to patients with severe left ventricular dysfunction. Great care should be taken in these seriously ill patients to guard against postablation ventricular arrhythmias.