Epicardial atrial defibrillation: successful treatment of postoperative atrial fibrillation

BACKGROUND: Atrial fibrillation is the most common complication after cardiac surgery. Current medical treatment using antiarrhythmics and anticoagulants has a significant morbidity. The goal of this study was to determine if epicardial atrial defibrillation can be safely performed and return patients to sinus rhythm. METHODS: A prospective analysis of patients undergoing cardiac surgery was performed. Patients with a prior pacemaker/defibrillator, history of arrhythmia, preoperative antiarrhythmic, age greater than 85 years, history of stroke, or intraaortic balloon pump were excluded. Temporary epicardial atrial cardioversion wires were placed on the right and left atrium. Bipolar atrial and ventricular pacing wires were also placed. The wires were tested in the operating room. Patients who went into postoperative arial fibrillation were cardioverted with 3 J, 6 J, or 9 J. RESULTS: There were 45 patients enrolled. Sixteen patients (35%) went into postoperative arial fibrillation during their hospital stay. Mean time to onset of arial fibrillation was 2.6 +/- 1.4 days after surgery. Fifteen patients were successfully cardioverted to sinus rhythm on the primary cardioversion, with mean of 5.7 +/- 2.4 J. One patient was cardioverted at 6 hours after onset of arial fibrillation, at 6 J. Recurrent arial fibrillation occurred in 4 patients during their hospital stay. All 4 of these patients were cardioverted with a mean of 6.4 +/- 2.6 J. All wires were removed the day before patients were discharged. There were no complications with wire insertion or removal. There were no adverse neurologic events. The mean hospital stay was 5.1 +/- 2.2 days. All patients were in sinus rhythm at 1 month follow-up. CONCLUSIONS: The use of a temporary atrial defibrillator to resynchronize patients in postoperative arial fibrillation is safe and effective.     

Postoperative atrial fibrillation in noncardiothoracic surgical patients

BACKGROUND: Atrial fibrillation is a common arrhythmia whose prevalence increases with age. It is a well-known complication of cardiothoracic surgery, but the incidence and contributing factors to the development of atrial fibrillation in noncardiothoracic surgical patients are less well known. This study was undertaken to investigate the incidence, association with known risk factors, treatment, and outcome of atrial fibrillation in postoperative noncardiac, nonthoracic surgical patients. METHODS: A 2-year retrospective review was performed of all noncardiac, nonthoracic surgical patients that developed atrial fibrillation within 30 days of operation. Incidence, risk factors, treatment and outcome related to the development of this arrhythmia were analyzed. RESULTS: Fifty-one patients developed atrial fibrillation during this study period for an incidence of 0.37%. Most had preexisting cardiac risk factors, a positive fluid balance, or had electrolyte or arterial oxygen saturation abnormalities. Two thirds were discharged home on new cardiac medications, 16% remained in atrial fibrillation, and 12% died. CONCLUSIONS: New onset atrial fibrillation in this group of noncardiothoracic surgical patients is an uncommon problem that is a morbid event associated with significant mortality.     

Rationale and management of perioperative atrial fibrillation

Atrial fibrillation is the most common clinically relevant arrhythmia. Anesthesiologists will be faced with atrial fibrillation of new or undetermined onset at their preoperative evaluation of patients as well as during intra- and post operative care. Because of fast electrophysical and structural remodeling, atrial fibrillation tends to persist and reoccur after successful conversion with increasing time of duration. Therefore, atrial fibrillation with an onset of less than 48 hours should be attempt to convert as soon as diagnostic work up has been made and possible causes have been corrected. New developments of electrophysiological and pharmacological treatment have improved the short term success rate of cardioversion. Further developments might give even more specific treatment options for the individual patient. In contrast, for treatment of chronic atrial fibrillation rate control therapy and thromboembolic prophylaxes seems to be more advisable with a lower risk of drug side effects and stroke. Anticoagulation should be initiated not later than 48 hours after the onset of atrial fibrillation. Finally, the development of implantable devices for the treatment of atrial fibrillation seem to be a promising therapeutic option for patients in end-stage heart diseases.     

Role of electrophysiological study and ablation in the management of recurrent atrial flutter associated with haemodynamic compromise in a critically ill patient

Atrial flutter is a common arrhythmia. In the critical care setting, the arrhythmia may present in any patient, but it is most commonly seen in patients with impaired ventricular function, valvular disease, atrial dilatation or after cardiac surgery. We present a 68-year-old lady with recurrent poorly tolerated atrial flutter that was resistant to multiple pharmacological interventions and complicated by cardiogenic shock following direct current cardioversion. The flutter was successfully cured with radiofrequency ablation and was followed by an immediate improvement in her haemodynamic status. We review the management of acute atrial flutter and discuss the role of electrophysiologically guided ablation.     

Atrial fibrillation after operation for lung cancer: clinical and prognostic significance

BACKGROUND: Atrial fibrillation is a common complication of early postoperative period in lung cancer thoracotomy. Its clinical incidence and short- and long-term impact on overall mortality has never been definitely assessed; moreover, it is unclear whether the arrhythmia represents an independent cardiac risk factor. METHODS: We prospectively studied 233 consecutive patients undergoing operation for lung cancer (170 with non-small-cell lung cancer). Postoperative atrial fibrillation incidence was related to different clinical factors possibly involved in its occurrence and to both short- and long-term survival. RESULTS: Atrial fibrillation occurred in 28 patients (12%) (same percentage in non-small-cell lung cancer); a strong relationship was observed between arrhythmia and age, history of hypertension and associated lymph node resection. The mean hospitalization time was 14 +/- 4 days in patients developing atrial fibrillation and 13 +/- 4 days in those who did not (p = not significant). No difference was observed between the two groups with regard to short- or long-term mortality or to long-term atrial fibrillation recurrences, also when considering the entire population and only non-small-cell lung cancer, separately. CONCLUSIONS: At our institution, early atrial fibrillation occurrence after operation for lung cancer does not show any negative impact on short- and long-term mortality or on recurrence rate.     

Tachykarde Rhythmusstörungen in der Notfall- und Rettungsmedizin: Von der Tablette bis zur Ablation

Tachycardiac arrhythmia (heart rate >100/min) requires rapid and targeted therapeutic strategies. Supraventricular tachycardia (SVT), such as sinus tachycardia atrial tachycardia, AV-nodal re-entry tachycardia and tachycardia due to accessory pathways are paroxysmal forms of tachycardia. All SVTs are usually characterized by small QRS complexes (QRS width <120 ms) during tachycardia. It is essential to evaluate the history of arrhythmia, to perform a thorough physical examination and to accurately analyze the 12-lead electrocardiogram. An exact SVT diagnosis is then possible in >90% of patients. Ventricular tachycardia (VT) has a broad QRS complex (QRS width ≥120 ms), ventricular flutter and ventricular fibrillation and is associated with chaotic electrophysiologic findings. For acute therapy of SVT vagal maneuvers, adenosine, class I anti-arrhythmic drugs, beta-blocking agents and calcium antagonists (type verapamil) can be used. If this therapy fails electrical DC cardioversion is mandatory. In patients with VT amiodarone is the treatment of choice as well as in patients with ventricular fibrillation or ventricular flutter refractory to cardioversion or defibrillation.     

Uso da ecocardiografia transesofágica no período perioperatório orientando a tomada de decisão durante a instabilidade hemodinâmica desencadeada por fibrilação atrial

Background and objective

Atrial fibrillation is the most common cardiac arrhythmia, which may occur during the perioperative period and lead to hemodynamic instability due to loss of atrial systolic function. During atrial fibrillation management, electrical cardioversion is one of the therapeutic options in the presence of hemodynamic instability; however, it exposes the patient to thromboembolic event risks. Transesophageal echocardiography is a diagnostic tool for thrombi in the left atrium and left atrial appendage with high sensitivity and specificity, allowing early and safe cardioversion. The present case describes the use of transesophageal echocardiography to exclude the presence of thrombi in the left atrium and left atrial appendage in a patient undergoing non‐cardiac surgery with atrial fibrillation of unknown duration and hemodynamic instability.

Atrial fibrillation after coronary artery bypass grafting. Is it a disorder of the elderly?

A total of 1666 patients undergoing isolated coronary artery bypass were studied for the occurrence of postoperative atrial fibrillation. Possible associations of this arrhythmia with various preoperative, intraoperative, and postoperative factors were studied by univariate (chi 2 and t tests) and multivariate (logistic regression) analyses. The overall incidence of postoperative atrial fibrillation was 28.4%, with the major occurrence 2 days after the operation. Both univariate and multivariate studies indicated the patient's age to be the dominant factor promoting postoperative atrial fibrillation, with an increasing prevalence in older patients (p = 0.0001). Multivariate analysis showed that postoperative beta-blocker therapy conveyed considerable protection against postoperative atrial fibrillation (p = 0.001) but was less effective in the older patients. Men were more prone to this arrhythmia (p = 0.02). Although these associations appeared significant, the logistic model proved to be a poor predictor of postoperative atrial fibrillation, which suggests that other factors not studied, or mere chance, may also be responsible.     

New-onset atrial fibrillation in critically ill adult patients—an SSAI clinical practice guideline

Background

Acute or new-onset atrial fibrillation (NOAF) is the most common cardiac arrhythmia in critically ill adult patients, and observational data suggests that NOAF is associated to adverse outcomes.

Methods

We prepared this guideline according to the Grading of Recommendations Assessment, Development and Evaluation methodology. We posed the following clinical questions: (1) what is the better first-line pharmacological agent for the treatment of NOAF in critically ill adult patients?, (2) should we use direct current (DC) cardioversion in critically ill adult patients with NOAF and hemodynamic instability caused by atrial fibrillation?, (3) should we use anticoagulant therapy in critically ill adult patients with NOAF?, and (4) should critically ill adult patients with NOAF receive follow-up after discharge from hospital? We assessed patient-important outcomes, including mortality, thromboembolic events, and adverse events. Patients and relatives were part of the guideline panel.

Results

The quantity and quality of evidence on the management of NOAF in critically ill adults was very limited, and we did not identify any relevant direct or indirect evidence from randomized clinical trials for the prespecified PICO questions. We were able to propose one weak recommendation against routine use of therapeutic dose anticoagulant therapy, and one best practice statement for routine follow-up by a cardiologist after hospital discharge. We were not able to propose any recommendations on the better first-line pharmacological agent or whether to use DC cardioversion in critically ill patients with hemodynamic instability induced by NOAF. An electronic version of this guideline in layered and interactive format is available in MAGIC: https://app.magicapp.org/#/guideline/7197 .

Conclusions

The body of evidence on the management of NOAF in critically ill adults is very limited and not informed by direct evidence from randomized clinical trials. Practice variation appears considerable.     

Atrial fibrillation after coronary artery bypass grafting without cardiopulmonary bypass.

OBJECTIVE: Atrial fibrillation is the most common complication after heart surgery. It rarely has a fatal outcome but causes patient instability, prolongs hospital stay, or even is the reason for perioperative infarction. Although conventional coronary artery bypass grafting (CABG) with cardiopulmonary bypass has excellent short-term and long-term results, the number of coronary operations on a beating heart without cardiopulmonary bypass is still growing. To reduce surgical trauma, off-pump coronary artery bypass grafting via sternotomy (OPCABG) or minimally invasive direct vision coronary artery bypass grafting (MIDCABG) via small thoracotomy are performed. The aim of this study was to estimate the frequency of atrial fibrillation in patients after myocardial revascularization without cardiopulmonary bypass. METHODS: A retrospective analysis of 48 patients undergoing myocardial revascularization without cardiopulmonary bypass was performed. Twenty-four patients underwent OPCABG and 24 were operated using the MIDCABG technique. The incidence of cardiac arrhythmias was analyzed since operation to the fourth postoperative day. Each patient had continuous ECG monitoring with option of arrhythmia analysis during ICU stay. After discharge from ICU 24-h ECG monitor studies were carried out. Surface 12-lead ECG was accomplished once a day, and additionally each time symptoms of cardiac arrhythmia occurred. Risk factors of atrial fibrillation were estimated. RESULTS: Atrial fibrillation occurred in 25% of patients after MIDCABG, in 29% after OPCABG, and in 18% after CABG with cardiopulmonary bypass. This difference has no statistical significance. Risk factors and incidence of postoperative complications were comparable in all groups. CONCLUSIONS: Atrial fibrillation is a common complication after procedures of myocardial revascularization, performed with or without cardiopulmonary bypass. The occurrence is not dependent on the type of operation.     

Patient-centered management of atrial fibrillation: applying evidence-based care to the individual patient

Atrial fibrillation is the most common arrhythmia encountered in clinical practice, and it is one of the most common cardiac conditions requiring hospitalization of a patient. Several national organizations have developed guidelines for the management of atrial fibrillation. These guidelines were updated in 2011 to incorporate new advances in antiarrhythmic drug therapy and anticoagulant therapy, as well as progress in the field of catheter ablation. Many decisions about patient care involve consideration of issues related to lifestyle and quality of life rather than survival. These decisions also involve addressing the key topics of heart rate control, heart rhythm control, and stroke prevention. During the past decade, important advances in the management of atrial fibrillation have created a number of treatment options that have roughly equivalent therapeutic efficacies when they are used for several common clinical situations encountered in clinical practice. The range of available treatments for patients with atrial fibrillation provides an important opportunity for the physician to deliver patient-centered care, which uses patient values to determine the best course of treatment.     

Poor maintenance of sinus rhythm after electrical cardioversion of patients with atrial fibrillation or flutter: a 5‐year follow‐up of 268 consecutive patients

Objective—To report long‐term results of direct current (DC)‐cardioversion in unselected patients with atrial fibrillation (AF) or flutter.

Design—The study was a retrospective 5‐year follow‐up of all patients undergoing DC‐cardioversion for AF or flutter at our institution between 1993 and 1997.

Results—Three hundred and eighty‐five DC‐cardioversions were performed in 268 patients. Two hundred and forty‐nine patients underwent cardioversion for the first time. Of these, 183 (74%) were converted to sinus rhythm. During the first month of follow‐up 105 (57%) relapsed into AF. Only 33 patients (13%) of the 249 patients scheduled for cardioversion remained in sinus rhythm after 1 year. In multivariate analysis arrhythmia duration was the only variable that was associated with successful cardioversion. Periprocedural complications occurred in 9.9% of the cardioversions.

Conclusion—In daily routine only a minority of patients will maintain sinus rhythm after DC‐cardioversion for AF or flutter. Also, DC‐cardioversion is not without risk. These observational data suggest a conservative approach to re‐establishment of sinus rhythm in patients with AF.     

Poor maintenance of sinus rhythm after electrical cardioversion of patients with atrial fibrillation or flutter: a 5-year follow-up of 268 consecutive patients

OBJECTIVE: To report long-term results of direct current (DC)-cardioversion in unselected patients with atrial fibrillation (AF) or flutter. DESIGN: The study was a retrospective 5-year follow-up of all patients undergoing DC-cardioversion for AF or flutter at our institution between 1993 and 1997. RESULTS: Three hundred and eighty-five DC-cardioversions were performed in 268 patients. Two hundred and forty-nine patients underwent cardioversion for the first time. Of these, 183 (74%) were converted to sinus rhythm. During the first month of follow-up 105 (57%) relapsed into AF. Only 33 patients (13%) of the 249 patients scheduled for cardioversion remained in sinus rhythm after 1 year. In multivariate analysis arrhythmia duration was the only variable that was associated with successful cardioversion. Periprocedural complications occurred in 9.9% of the cardioversions. CONCLUSION: In daily routine only a minority of patients will maintain sinus rhythm after DC-cardioversion for AF or flutter. Also, DC-cardioversion is not without risk. These observational data suggest a conservative approach to re-establishment of sinus rhythm in patients with AF.     

Atrial fibrillation,failed cardioversion,and electroconvulsive therapy

A case is described in which an elderly male with atrial fibrillation and major depression underwent a course of electroconvulsive therapy. Two of the first three treatments were associated with other arrhythmias, during and after the procedure. Prior to the fourth treatment cardioversion was unsuccessful. During the fourth episode of electroconvulsive therapy, the patient reverted to sinus rhythm and remained in this rhythm. Reversion of atrial fibrillation to sinus rhythm may be associated with embolization if atrial thrombus has formed. Factors predisposing to changes in rhythm with electroconvulsive therapy and the management of patients with atrial fibrillation having electroconvulsive therapy are discussed.     

Atrial fibrillation in a tertiary care multidisciplinary intensive care unit--incidence and risk factors

Atrial fibrillation is a common arrhythmia in an intensive care unit. We performed a prospective observational study over a period of three months, to study the incidence, risk factors and outcome of patients who develop atrial fibrillation in a multidisciplinary intensive care unit. All patients above the age of 50 years were eligible. Exclusion criteria were: cardiac or oesophageal surgery during current hospitalisation, atrial fibrillation at admission, implanted pacemaker and expected intensive care unit stay of less than 24 hours. Sixty-one patients were included in the study. Eighteen patients (29.5%, confidence interval 18-40) developed atrial fibrillation. Incidence of atrial fibrillation was 4.02 episodes per 100 patient days. Patients who developed atrial fibrillation had higher age (71.3 years vs. 63.2 years, P=0.001), severity of illness (APACHE II 25.4 vs. 20.0, P=0.005) and sepsis at admission (9/18 vs. 9/43, P=0.01). They also had higher in-hospital mortality (Risk ratio 2.7, 95% confidence interval 1.3-5.4). Standardised mortality ratio was higher in patients who developed atrial fibrillation (1.08 vs. 0.63). Patients who developed atrial fibrillation required a longer period of mechanical ventilation and inotropic support. Multivariate logistic regression analysis showed age >75 years, APACHE II score >20 and sepsis at admission were independent predictors for development of atrial fibrillation in critically ill patients. Although atrial fibrillation by itself is unlikely to be the cause of higher mortality, it is likely to be a marker for increased mortality and resource utilisation in the intensive care unit.     

Did the introduction of a minimally invasive technique change the incidence of atrial fibrillation after single internal thoracic artery-left anterior descending artery grafting?

OBJECTIVE: Atrial fibrillation after coronary artery bypass operations remains frequent and increases morbidity, as well as resource use. Its cause remains unclear. The introduction of a minimally invasive technique provides an opportunity to evaluate the effect of intraoperative factors, such as cardiopulmonary bypass, global myocardial ischemia, and myocardial protection technique, on the occurrence of this arrhythmia. METHODS: All the patients undergoing isolated left internal thoracic artery-left anterior descending artery grafting between January 1994 and December 1999 were reviewed. Twenty possible risk factors for postoperative atrial fibrillation, including the choice of operative technique--minimally invasive technique was introduced in January 1997--were entered into univariate and multivariable logistic regression analysis. RESULTS: Postoperative atrial fibrillation occurred in 36 (20%) of 183 patients. On univariate analysis, age (P <.001) and a history of supraventricular arrhythmia (P <.001) were found to be risk factors. In particular, 15 (22%) of 69 patients operated on with the minimally invasive technique had postoperative atrial fibrillation versus 21 (18%) of 114 in the standard group (P =.58). On multivariable analysis, including the operative technique, the same variables (P =.001 and.01, respectively) were identified as independent risk factors. CONCLUSIONS: The introduction of a minimally invasive technique for coronary artery bypass operations did not reduce the occurrence of postoperative atrial fibrillation in this study population. This suggests that prophylactic measures to reduce this arrhythmia should be focused on factors unrelated to cardiopulmonary bypass or myocardial preservation technique.     

Left atrial appendage outflow velocity index is superior to conventional criteria for prediction of maintenance of sinus rhythm after cardioversion. An echocardiographic study in patients with atrial fibrillation of a few months' duration

OBJECTIVE: To investigate whether left atrial appendage outflow velocity alone or in relation to left atrial diameter is a superior predictor of sinus rhythm maintenance after cardioversion compared with traditional clinical or echocardiography parameters. DESIGN: Sixty-two patients with their first episode of atrial fibrillation were examined using echocardiography before DC-cardioversion. At one month's follow-up, 42 patients had maintained sinus rhythm (group A), and 20 had relapsed into atrial fibrillation (group B). There were no differences in arrhythmia duration or antiarrhythmic therapy between the groups. RESULTS: Left atrial diameter measured by echocardiography was smaller in group A (42 mm, 95% CI 40.9-44.1 mm) compared with group B (46 mm, 95% CI 43.4-48.2, p < 0.05). Patients in group A had a higher left atrial appendage outflow velocity at 0.44 m/s (95% CI 0.39-0.49) compared with 0.34 m/s (95% CI 0.30-0.37) in group B (p < 0.01). The ratio of left atrial appendage flow to left atrial diameter was 0.011 (95% CI 0.009-0.012) in group A compared with 0.008 (95% CI 0.007-0.009) in group B, and 63% (95% CI 33-78) of the patients in group A had velocity ratio >0.009 compared with 20% (95% CI 2-38) in group B, (p < 0.01). Stepwise multiple logistic regression analysis showed that a velocity ratio >0.009 was the only predictor for maintenance of sinus rhythm one month after cardioversion with an odds ratio of 6.4 (95% CI 1.9-23.8), (p = 0.004). CONCLUSION: The ratio of left atrial appendage outflow velocity to left atrial diameter is superior to the traditionally used criteria for prediction of maintenance of sinus rhythm following DC-conversion of first-episode atrial fibrillation.     

The surgical treatment of atrial fibrillation. I. Summary of the current concepts of the mechanisms of atrial flutter and atrial fibrillation

Atrial fibrillation is a common arrhythmia that is frequently resistant to medical therapy and has no satisfactory surgical therapy. The development of an effective surgical procedure to treat atrial fibrillation has been hampered by the paucity of clinically relevant information on the basic mechanisms responsible for the arrhythmia. This paper summarizes the current concepts of the electrophysiologic abnormalities in atrial flutter and fibrillation.     

Procainamide infusion and acute atrial fibrillation

We report the use of intravenous procainamide infusion in the treatment of fifteen patients with acute atrial fibrillation. Procainamide was infused at 50 mg/min to a maximum of 20 mg/kg, with blood pressure and electrocardiographic monitoring. Ten patients responded, with a mean dose of 8.7 (standard deviation 4.3) mg/kg, four of these reverting to sinus rhythm after a low dose of less than 5.0 mg/kg. Hypotension was a common concomitant and was seen in four cases, but required termination of the infusion only in a patient with cardiomyopathy. An increase in ventricular rate or conversion to atrial flutter was not seen. Intravenous infusion of procainamide is a safe and moderately effective method of cardioversion in acute atrial fibrillation.     

Cardiac arrhythmias in cardiothoracic surgery

Most patients with cardiopulmonary disease are predisposed to develop perioperative arrhythmias with the individual patient risk depending upon the type of operative procedure performed, the risk profile of the patient, and the complexity of the post-operative course. There are several management options that may tend to prevent perioperative arrhythmias that should be considered in certain patient subsets. Most important of these is the use of beta-blocker therapy before and after operation in patients with coronary risks factors undergoing non-cardiac thoracic procedures and in patients having coronary artery bypass grafting. The common supraventricular arrhythmias including atrial fibrillation and flutter, multifocal atrial tachycardia, and paroxysmal supraventricular tachycardia must be properly diagnosed and treated appropriately. Placement of atrial pacing wires for use after open cardiac surgery is of great value both for diagnosis, and in some cases, for treatment of arrhythmias. Fortunately, serious life threatening ventricular arrhythmias occurs less commonly but the clinician must recognize and correct important predisposing factors and know how to treat these when they occur. A specific protocol for arrhythmia management that sets guidelines for drug choice and therapies for each of the common arrhythmias is useful for clinicians and adds predictability to patient care.