27 Aug 12
By J Chenoweth, D Diercks
Curr Op Crit Care 2012;18: 333–340
The review aims to describe the scope of the problem and potential therapeutic intervention for the management and risk stratification of patients with atrial fibrillation in the emergency department and acute care setting.
Atrial fibrillation is the most common arrhythmia prompting admission to the hospital. Management strategies include determining the trigger of the arrhythmia, rate control, and potential cardioversion. In the acute care setting the treatment is often dependent on the timing of the onset of arrhythmia. In those patients presenting with symptoms of less than 48 h of duration management may consist of rate control, pharmacologic, or electrical cardioversion. Recent studies suggest no difference in long-term outcomes with rate and rhythm control. In patients with symptoms greater that 48 h rate control is the initial option with potential for cardioversion as an outpatient. There are recent advances in ablation that provide additional options to patients with paroxysmal atrial fibrillation. An essential component of the treatment strategy for these patients is risk stratification for stroke and the initiation of long-term anticoagulation in appropriate patients.
Management of atrial fibrillation is guided by underlying causes of the atrial fibrillation and duration of symptoms.
11 Apr 10
By S Goodman, Y Weiss and C Weissman
Curr Opin Crit Care 2008;14:549–554
Purpose of review
To explore recent findings on the treatment and outcome of cardiac arrhythmias and how they affect ICU activities.
The rate vs. rhythm control debate for the treatment of chronic atrial fibrillation continues. It is still unclear whether the postcardiac surgery inflammatory response contributes to the development of atrial fibrillation. In noncardiothoracic surgery/trauma patients hospitalized in an ICU, new-onset supraventricular arrhythmias are associated with markedly elevated mortality when compared with patients with a prior history of such arrhythmias and patients who do not develop arrhythmias. The onset of new supraventricular arrhythmias in such patients appears to be a manifestation of multiple system organ failure as it is closely associated with sepsis. Cardioversion of supraventricular arrhythmias with biphasic waveforms is being studied to determinewhether it is more effective than cardioversion with monophasic waveforms.
Supraventricular arrhythmias, especially atrial fibrillation, occur frequently in ICU patients. Intensivists not only treat atrial fibrillation itself but also its complications and the complications of the therapies used to prevent these complications. In ICUpatients, ventricular arrhythmias have ominous implications because they usually portend either a major cardiac or a systemic dysfunction or both.
20 Dec 09
By G Steinbeck, D Andresen, K Seidl, J Brachmann, E Hoffmann et al; for the IRIS Investigators
The rate of death, including sudden cardiac death, is highest early after a myocardial infarction. Yet current guidelines do not recommend the use of an implantable cardioverter–defibrillator (ICD) within 40 days after a myocardial infarction for the prevention of sudden cardiac death. We tested the hypothesis that patients at increased risk who are treated early with an ICD will live longer than those who receive optimal medical therapy alone.
This randomized, prospective, open-label, investigator-initiated, multicenter trial registered 62,944 unselected patients with myocardial infarction. Of this total, 898 patients were enrolled 5 to 31 days after the event if they met certain clinical criteria: a reduced left ventricular ejection fraction (<40%) and a heart rate of 90 or more beats per minute on the first available electrocardiogram (ECG) (criterion 1: 602 patients), nonsustained ventricular tachycardia (>150 beats per minute) during Holter monitoring (criterion 2: 208 patients), or both criteria (88 patients). Of the 898 patients, 445 were randomly assigned to treatment with an ICD and 453 to medical therapy alone.
During a mean follow-up of 37 months, 233 patients died: 116 patients in the ICD group and 117 patients in the control group. Overall mortality was not reduced in the ICD group (hazard ratio, 1.04; 95% confidence interval [CI], 0.81 to 1.35; P=0.78). There were fewer sudden cardiac deaths in the ICD group than in the control group (27 vs. 60; hazard ratio, 0.55; 95% CI, 0.31 to 1.00; P=0.049), but the number of nonsudden cardiac deaths was higher (68 vs. 39; hazard ratio, 1.92; 95% CI, 1.29 to 2.84; P=0.001). Hazard ratios were similar among the three groups of patients categorized according to the enrollment criteria they met (criterion 1, criterion 2, or both).
Prophylactic ICD therapy did not reduce overall mortality among patients with acute myocardial infarction and clinical features that placed them at increased risk.
19 Jul 08
By D Roy, M Talajic, S Nattel, D G Wyse, P Dorian, et al for the Atrial Fibrillation and Congestive Heart Failure Investigators
It is common practice to restore and maintain sinus rhythm in patients with atrial fibrillation and heart failure. This approach is based in part on data indicating that atrial fibrillation is a predictor of death in patients with heart failure and suggesting that the suppression of atrial fibrillation may favorably affect the outcome. However, the benefits and risks of this approach have not been adequately studied.
We conducted a multicenter, randomized trial comparing the maintenance of sinus rhythm (rhythm control) with control of the ventricular rate (rate control) in patients with a left ventricular ejection fraction of 35% or less, symptoms of congestive heart failure, and a history of atrial fibrillation. The primary outcome was the time to death from cardiovascular causes.
A total of 1376 patients were enrolled (682 in the rhythm-control group and 694 in the rate-control group) and were followed for a mean of 37 months. Of these patients, 182 (27%) in the rhythm-control group died from cardiovascular causes, as compared with 175 (25%) in the rate-control group (hazard ratio in the rhythm-control group, 1.06; 95% confidence interval, 0.86 to 1.30; P=0.59 by the log-rank test). Secondary outcomes were similar in the two groups, including death from any cause (32% in the rhythm-control group and 33% in the rate-control group), stroke (3% and 4%, respectively), worsening heart failure (28% and 31%), and the composite of death from cardiovascular causes, stroke, or worsening heart failure (43% and 46%). There were also no significant differences favoring either strategy in any predefined subgroup.
In patients with atrial fibrillation and congestive heart failure, a routine strategy of rhythm control does not reduce the rate of death from cardiovascular causes, as compared with a rate-control strategy.