Late Postoperative Arrhythmias Research Articles

Right atrial reverse remodeling and risk of atrial arrhythmias after surgical pulmonary valve replacement

BackgroundRight atrial (RA) dysfunction and atrial arrhythmias are relatively common in adults with repaired tetralogy of Fallot. The purpose of this study was to determine whether RA function improved after surgical pulmonary valve replacement (PVR), and the association between postoperative RA reverse remodeling and late postoperative atrial arrhythmias. MethodRA reverse remodeling (ΔRA reservoir strain based speckle tracking echocardiography) was calculated as: ([postoperative RA reservoir strain – preoperative RA reservoir strain]/preoperative RA reservoir strain)x100. Optimal RA reverse remodeling was defined as ΔRA reservoir strain >15%. ResultsOf 411 patients (age 36 ± 13 years), preoperative RA reservoir strain was 31 ± 13%, postoperative RA reserve remodeling was 13 ± 9%, and 171 (42%) had optimal RA reserve remodeling. Preoperative RA reservoir strain (β±SE 1.12 ± 0.09, p < 0.001) was associated with postoperative RA reverse remodeling on multivariable analysis. Preoperative RA reservoir strain ≥33% predicted optimal postoperative RA reverse remodeling (area under the curve 0.792).ΔRA reservoir strain was associated with postoperative atrial arrhythmias (HR 0.91, 95%CI 0.86–0.96, p = 0.004), on multivariable analysis. Compared to patients with preoperative RA reservoir strain <33% (n = 242, 59%), those with RA reservoir strain ≥33% (n = 169, 41%) had more robust RA reverse remodeling (ΔRA reverse remodeling 19 ± 11% versus 7 ± 10%, p < 0.001), and lower incidence of atrial arrhythmias (1.1% versus 2.9%, p = 0.003). ConclusionsPreoperative RA reservoir strain was associated with RA reverse remodeling after PVR, and in turn, postoperative atrial arrhythmia. These results suggest that RA strain indices could be used to determine optimal timing for PVR in order to reduce the risk of atrial arrhythmia.

Early and late post-operative arrhythmias after surgical myectomy: 45 years of follow-up

AimsThe aims of this study are to investigate the incidence and determinants of post-operative atrial arrhythmias, conduction disorders and mortality in hypertrophic obstructive cardiomyopathy (HOCM) patients undergoing transaortic myectomy. Methods and resultsThis retrospective single-center study was conducted in 249 patients (median age 54 years [40–64], 42% female) undergoing transaortic myectomy. Post-operative atrial fibrillation (AF) was reported in 84 patients (33.7%), including 56 patients (22.5%) with de novo AF. Older age (HR = 1.027 (1.003–1.052), p = 0.029) and hypercholesterolemia (HR = 2.296 (1.091–4.832) p = 0.029) were independent predictors for de novo post-operative AF. Late post-operative AF and atrial flutter (AFL) occurred in 18.9% and 6.8% of the patients, respectively. De novo early post-operative AF increased the risk of late post-operative AF (HR = 3.138 (1.450–6.789), p = 0.004). Patients with a right bundle branch block had a higher risk of early-postoperative pacemaker implantation (p = 0.003, HR = 9.771 (2.195–43.505)). Higher age at time of surgery (HR = 1.053 (1.026–1.081), p < 0.001) was a predictor for late mortality (n = 47, 18.9%). ConclusionEarly and late post-operative AF, AFL and other SVTs are common sequelae after myectomy and are associated with older age at surgery, history of AF and early post-operative AF. Early post-operative arrhythmias are not transient and periodic rhythm monitoring is therefore essential to initiate therapy as soon as possible.

Intraoperative arrhythmias in children with congenital heart disease: transient, innocent events?

The significance and incidences of intraoperative arrhythmias occurring in the operating room (OR) in children with congenital heart disease (CHD) are unknown. Aims of this study were to determine incidences of intraoperative arrhythmias in children with CHD and to examine whether they are associated with persistent arrhythmias during follow-up. Continuous ECG recordings obtained from 134 consecutive paediatric CHD patients were manually examined from the moment the aortic cross-clamp (ACC) was removed [use of ACC and cardiopulmonary bypass (CPB)], when CPB was stopped (use of only CPB) or when the sternum was closed (no use of ACC and CPB) until departure from the OR. In the OR, 2nd (60%) and 3rd (34%) degree atrioventricular conduction block (AVB), ectopic atrial rhythm (30%), and junctional rhythm (32%) were most often observed in patients who underwent surgery with both ACC and CPB. Incidences of these arrhythmias decreased after cessation of CPB (P < 0.01). (Supra)ventricular premature beats were mostly observed between end of ACC time and sternum closure (64-84%), but decreased before departure from the OR (6-16%, P < 0.01). During a median follow-up of 37 months, 17 patients (13%) had new onset, late post-operative arrhythmias. Of these patients, 88% had intraoperative arrhythmias compared with 85% of patients without late post-operative arrhythmias (P = 1). Intraoperative arrhythmias, mainly 2nd degree AVB and (supra)ventricular premature beats, were frequently observed in children with CHD undergoing cardiac surgery with use of CPB and ACC. Most arrhythmias were short-lasting and transient and appeared not to be related to late post-operative arrhythmias.

Prevalence of Arrhythmias Late After the Fontan Operation

The extracardiac conduit (ECC) modification of the Fontan procedure has been theorized to reduce the risk of sinus node dysfunction and atrial arrhythmia compared with the intra-atrial lateral tunnel (ILT) Fontan. This study aimed to compare the prevalence of early and late arrhythmias in patients who underwent ECC and ILT Fontan from a similar era with long-term follow-up at a single institution. A retrospective cohort study was conducted of all patients who underwent ECC or ILT Fontan from 1995 to 2005 at The Children's Hospital of Philadelphia. Bradyarrhythmias (including sinus node dysfunction), tachyarrhythmias, and pacemaker burden prevalence was determined throughout early (<30 days) and late (>30 days) postoperative periods. Of 434 patients undergoing the Fontan procedure during the study period, a total of 87 and 106 patients who underwent ECC and ILT Fontan, respectively, met the inclusion criteria. There were no significant differences in risk of sinus node dysfunction or tachyarrhythmia in both early and late postoperative periods. Although the overall risk of late postoperative pacemaker therapy was lower for the ECC cohort (4.9% vs 15.7%, p=0.03), when adjusting for follow-up time, no significant difference was observed (odds ratio 3.1, 95% confidence interval 0.6 to 15.2, p=0.16). In conclusion, the overall prevalence of late postoperative arrhythmias observed after contemporary Fontan modifications is low. Intra-atrial reentrant tachycardia, a potentially fatal complication of the atriopulmonary Fontan operation was infrequently encountered in both ECC and ILT Fontan cohorts. Pacemaker use was higher in the ILT group, although this difference may be explained by differences in follow-up time. Despite the low prevalence of arrhythmias after contemporary Fontan modifications, ongoing surveillance is warranted as the onset of arrhythmias may emerge after longer follow-up time.

Surgical correction of atrial septal defect in the elderly.

IntroductionAtrial septal defects (ASDs) are one of the most common congenital malformations in adults. Correction of ASDs in advanced age remains controversial, even though beneficial effects in this patient group were found in recent studies. In older patients, less invasive transcatheter closure of ASDs has been recommended.AimThe aim of this study was to analyze our advanced age ASD surgical cohort: early and late results.Material and methodsRetrospective analysis of 32 patients operated on at an age of ≥ 60 years (i.e. age 66.13 ± 4.8, range from 60 to 78) in our center between 2001 and 2011 was carried out. We reviewed our experience of surgical ASD closure in elderly patients over a 10-year period to assess the effects of this type of treatment on early postoperative and long-term survival, early and late complications, preoperative and postoperative clinical status (New York Heart Association [NYHA] functional class), pulmonary hypertension (PH) and atrial arrhythmias. The patients were divided into two groups according to age.ResultsThe frequency of comorbidities was lower in younger age group patients (11 [61%] vs. 13 [93%], p < 0.05). Atrial fibrillation/flutter was found in 21 (66%) of all patients. Late postoperative mortality was higher in the older patient group (3 [21%] vs. 1 [5.6%]). Despite this, we observed significant improvement of symptoms and functional ability in the older population after surgical ASD closure (group I, n = 10 [56%] vs. group II, n = 12 [86%]).ConclusionsSurgical correction of clinically significant ASD is effective even in older patients with comorbidities.

Management of late atrial tachyarrhythmia long after Fontan operation

The optimal management of atrial tachyarrhythmia (AT) late after Fontan operation has not yet been established. Of 199 patients who were followed for more than 10 years after Fontan operation, 60 patients in whom late postoperative arrhythmias were observed were the subjects of this study. These arrhythmias were managed with anti-arrhythmic drugs. Twenty-one of 60 patients (35%) did not respond to the drugs and they needed further interventions. Fourteen catheter ablation procedures were performed in nine patients (atrial fibrillation in one patient, AT in eight patients) and the success rate was 44%. Conversion to total cavopulmonary connection (TCPC) was performed in 14 patients and Maze operation was performed at the time of Fontan conversion in 6 patients. Sinus rhythm or pacemaker rhythm was maintained in 7 of 14 (50%) patients postoperatively. Although arrhythmogenic substrates accumulate and tachyarrhythmia becomes frequent over the long-term following Fontan operation, most patients with AT can be managed medically. The success rate of catheter ablation and Maze operation is low but those interventions may be indicated in patients with intractable arrhythmias.

Proarrhythmic Aspects of Atrial Fibrillation Surgery

Surgery for the treatment of atrial fibrillation may be associated with early or late postoperative atrial arrhythmias. In many cases, the arrhythmias that occur early in the postoperative course may be related to pericardial inflammation or increased catecholamine levels and tend to resolve without further therapy. In contrast, late postoperative arrhythmias often are persistent, highly symptomatic, and refractory to medical therapy. The incidence and mechanisms of these late atrial arrhythmias have not been thoroughly described. In this study, a total of 143 consecutive patients undergoing atrial fibrillation surgery from 1996 to 2005 were prospectively followed up. Sustained atrial tachycardia developed in 22 of 143 patients (15%) >8 weeks after the surgical procedure. These patients underwent electrophysiological study. A total of 25 separate tachycardias were mapped in these 22 patients, including 15 located in right atrium and 10 in the left atrium. Right atrial tachycardias included cavotricuspid isthmus-dependent atrial flutter (n=7), non-isthmus-dependent right atrial reentry (n=7), and 1 focal atrial tachycardia. Left atrial tachycardias included reentry around the mitral valve (n=3) and in the roof of the left atrium (n=7). All tachycardias were successfully treated with radiofrequency catheter ablation with no recurrences in long-term follow-up. Postoperative arrhythmias are not uncommon late after surgery for atrial fibrillation and typically are reentrant and related to surgically created boundaries. Radiofrequency catheter ablation is highly effective in the management of these late arrhythmias.

Specific Issues After Extracardiac Fontan Operation: Ventricular Function, Growth Potential, Arrhythmia, and Thromboembolism

The purpose of this study was to define the prevalence of specific sequelae after extracardiac Fontan operation. Sixty-five consecutive patients undergoing extracardiac Fontan operation were studied for mortality, Fontan failure, systemic ventricular function, supraventricular arrhythmias, thromboembolism, and growth potential. Age was 3 to 31 years (mean +/- standard deviation, 9.4 +/- 1.8; median, 7 years). The conduits were constructed of polytetrafluoroethylene (n = 50), and "viable" in situ pericardium (n = 15). The patients underwent serial echocardiogram, dynamic radionuclide studies, and cardiac catheterization. Operative mortality was 3%, and the incidence of conduit thrombosis was 4.6%. There was paradoxic filling of the right lung after femoral injection of the radiotracer in all cases of conduit obstruction. Perioperative and late postoperative supraventricular arrhythmias were observed in 9.2% and 4.7% of patients, respectively. Risk factors for supraventricular arrhythmias included systemic ventricular dysfunction (p = 0.000), heterotaxy syndrome (p = 0.008), systemic venous anomalies (p = 0.015), and previous bidirectional Glenn operation (p = 0.017). At a mean follow-up of 77 +/- 2 months (range, 8 to 79 months), there were no late deaths (actuarial survival at 79 months, 96.9% +/- 0.02%). Serial echocardiograms demonstrated evidence of growth of the viable tunnels. Postoperatively, there was transient depression of ejection fraction in all patients (p = 0.000). Supraventricular arrhythmias after extracardiac Fontan are more common in patients with heterotaxy syndrome, bilateral superior venae cavae, systemic ventricular dysfunction, and those undergoing completion Fontan operation. The viable tunnel may emerge as an optimal alternative by virtue of reduction of supraventricular arrhythmias, elimination of the need for anticoagulation, and addressing the issue of growth potential in selected patients.

Postoperative arrhythmia.

Postoperative arrhythmia is a major cause of morbidity and mortality after cardiac surgery for congenital heart disease. Rhythm disturbances that may be well tolerated in a normal heart often cause hemodynamic instability when they occur in the immediate postoperative period. In the face of pre-existing myocardial dysfunction resulting from preoperative pressure or volume overload, patients with congenital heart conditions are especially vulnerable to rhythm disturbances after cardiac surgery. Cardiopulmonary bypass, intraoperative injury to the conduction system and myocardium, postoperative metabolic abnormalities, electrolyte disturbances, and increased adrenergic tone in response to the stress of the surgery or inotropic agents are also known factors associated with increased risk of arrhythmia in the immediate postoperative period. Surgically related arrhythmia can also present in the late postoperative period, particularly in association with surgical incision sites and surgically induced hemodynamic abnormalities. Early and late postoperative arrhythmias are important risk factors for morbidity and mortality after surgical treatment of many forms of congenital heart disease. This review describes the incidence of the most common forms of arrhythmia and recent advances in their diagnosis and treatment.

The Favorable Impact of Arrhythmia Surgery on Total Cavopulmonary Artery Fontan Conversion

Patients who have undergone atriopulmonary Fontan procedures are at risk for significant atrial arrhythmias and obstructive connections, which have been related to intra-atrial suture lines, atrial enlargement, and somatic growth. Twenty patients (mean age, 17.3 +/- 6.8 years) had conversion to total cavopulmonary artery connection 8.9 +/- 2.1 years after the previous Fontan procedure (for atrial arrhythmias in 19 patients and for obstructive lesions in one). Arrhythmia ablative surgery evolved over the study period from "arrhythmia circuit cryoablation" (cryoablation lesions completing lines of block) to the more standard approaches of modified right-sided Maze and Maze-Cox III procedures. Preoperative functional New York Heart Association class was IV in nine patients, III in nine, and II in two. All patients survived. Two patients had prolonged chest drainage (there was pericardial effusion in one). The average length of hospital stay was 11.3 +/- 5.4 days; chest tubes were removed on day 8.5 +/- 5.4. There were no long-term deaths (mean follow-up period, 20.3 +/- 14.9 months; range, 2 months to 4 years). Late postoperative arrhythmias occurred in two patients who are receiving long-term antiarrhythmic medications. All patients have improved to New York Heart Association class I or II. Total cavopulmonary artery Fontan conversion in association with modified right-sided Maze or Maze-Cox III procedures and pacemaker placement can be accomplished with low morbidity and mortality, and results in functional class improvement and control of life-threatening arrhythmias. Copyright 1999 by W.B. Saunders Company

Magnesium and calcium changes in serum and atrial muscle caused by open heart surgery and the effect of preoperative oral magnesium administration

The study was undertaken to compare magnesium and calcium serum concentration levels and magnesium and calcium atrial muscle content of between the non-magnesium group (20 patients) and the magnesium group (11 patients) in the perioperative period of open heart surgery. In addition, the incidence of arrhythmias was compared between the two groups. Late ventricular potentials and postoperative ventricular arrhythmias were evaluated in both groups. The patients of the magnesium group were administered a daily oral intake of 3.0 g of magnesium oxide for ten days before operation. In both groups, serum concentration of magnesium decreased abruptly due to hemodilution after the operation and began increasing gradually from 24 hours after the operation. However, in the non-magnesium group the concentration decreased below the normal range in the 24 hour period after the operation and elevated to above the preoperative value from the third to fifth postoperative days. In the magnesium group serum concentration of magnesium was higher during the 24 hours after the operation and lower from the third to fifth postoperative days than the non-magnesium group. Thus, the fluctuation was smaller in the magnesium group than the non-magnesium group. Serum concentration of calcium also decreased abruptly after the operation and gradually increased in the postoperative days in both groups. However, the level was always higher in the magnesium group than the non-magnesium group. The concentration ratio of serum calcium to magnesium was relatively unchanged postoperatively in the magnesium group, whereas it decreased significantly from the second to seventh postoperative days in the non-magnesium group. Magnesium and calcium contents in the atrial muscle were measured before and after cardiopulmonary bypass. Before bypass, magnesium and calcium contents were higher in the magnesium group than the non-magnesium group. However, in the non-magnesium group the calcium content increased significantly after bypass compared to pre-bypass levels, whereas it was unchanged in the magnesium group. Ventricular arrhythmias severer than grade 3 were found in 4 cases in the non-magnesium group. On the other hand, no ventricular arrhythmias severer than grade 3 were found in the magnesium group. As to the incidence of supraventricular arrhythmias, no difference was demonstrated between both groups. The appearance of late ventricular potentials on signal averaged electrocardiograms was found variable and often transient, and no association was found between the appearance of late ventricular potentials and the incidence of ventricular arrhythmias. Smaller fluctuations of magnesium and calcium concentrations in serum as well as in the atrial muscle were observed in the postoperative days in the magnesium group. Magnesium and calcium ratio also showed smaller fluctuations in the postoperative days in the magnesium group. In conclusion, these factors, along with suppression of calcium influx in the cardiac muscle, appeared to serve to reduce the incidence of ventricular arrhythmias in the magnesium group.

Arrhythmias after the Fontan procedure.

To study the determinants and outcome of arrhythmias after the Fontan type operation. Retrospective analysis of data in patients operated on between 1972 and 1986 (follow up 5-19 years (mean 12 years)). All 60 patients undergoing a Fontan type procedure at the National Heart Hospital, London, during the study period (mean age (SD) 12.3 (6.8) years). Postoperative arrhythmias occurred in 34 patients (57%), and 11 (58%) of 19 early postoperative deaths (within seven days) were related to arrhythmias. Early arrhythmias occurred in 19 (32%) patients of whom 11 (58%) died. All patients with early atrial fibrillation and His bundle tachycardia died and only preoperative atrial fibrillation recurred early. There was a higher incidence of early arrhythmias, which were less well tolerated, in double inlet single ventricle patients (9/19) than in those with tricuspid atresia (8/37). There were no other preoperative determinants of early arrhythmias or deaths from early arrhythmia. Late (after seven days) arrhythmias occurred in 15 (37% of hospital survivors). They had higher right atrial (RA) pressures both early and late after operation and had lower ventricular ejection fractions late after operation. Of those with atrial arrhythmias 86% had RA obstruction and 57% had an RA thrombus or pulmonary embolism at presentation; this was also confirmed in two patients in whom late sudden deaths occurred. Atrial fibrillation early after reoperation for RA obstruction was fatal. The actuarial arrhythmia free survival for hospital survivors was 60% at 10 years. Early postoperative arrhythmias were poorly tolerated, particularly atrial fibrillation and His bundle tachycardia. Previous atrial fibrillation was a relative contraindication to this procedure. Late postoperative arrhythmias were associated with higher RA pressures measured both early and late after operation and worse late ventricular function. Late arrhythmias may be the first manifestation of RA obstruction, which must be sought. RA thrombus was common in patients with atrial arrhythmias and should be treated early with anticoagulants.

Late postoperative arrhythmias following repair of Tetralogy of Fallot: Comparison between trans-atrial and trans-ventricular approaches

Late postoperative arrhythmias following repair of Tetralogy of Fallot: Comparison between trans-atrial and trans-ventricular approaches

Predictors of rhythm disturbances and subsequent morbidity after the Fontan operation

The electrocardiographic, hemodynamic and surgical data of 30 patients who underwent a Fontan operation between 1977 and 1986 were retrospectively reviewed to identify the incidence and predictors of immediate and late postoperative arrhythmias and associated morbidity in long-term survivors. Of 4 patients who died <1 year after operation (mortality 13%), 1 death was related to an arrhythmia. Three patients were not in sinus rhythm before operation and were excluded from the statistical analysis that examined predictors of arrhythmias. The remaining 23 long-term survivors have been followed 6.3 ± 2.6 years (mean ± standard deviation) since surgery and all remain in New York Heart Association functional class I or II. Ten patients (43%) developed immediate postoperative arrhythmias (≤ 30 days) whereas 11 (48%) had late arrhythmias. With up to 10.7 years of followup, the proportion of patients free from late arrhythmias continues to decline. Arrhythmias included bradyarrhythmias, atrial tachyarrhythmias, the tachy-brady syndrome and supraventricular ectopic activity. Immediate postoperative arrhythmias predicted late arrhythmias (p = 0.022). The preoperative electrocardiogram was the only variable useful in predicting both immediate and late postoperative arrhythmias. A more negative P-wave deflection in lead V 1 (-2.4 ± 0.7 vs -1.4 ± 1.2 mV, p = 0.02) predicted patients with immediate postoperative arrhythmias, whereas both greater P-wave duration and a more negative deflection in this lead predicted late arrhythmias (103 ± 14 vs 83 ± 20 ms, p = 0.01, and -2.5 ± 0.8 vs −1.3 ±1.0 mV, p = 0.005, respectively). Of the 26 surviving patients, 10 (38%) have required ≥1 hospitalizations for control of late arrhythmias. Eight patients are receiving maintenance therapy with multiple antiarrhythmic drugs including amiodarone (1 patient) and 5 have received permanent epicardial pacemakers. Thus, despite excellent functional results after the Fontan operation, postoperative arrhythmias are frequent and cause significant morbidity that will continue to increase with time. Atrial abnormalities on the preoperative electrocardiogram predict those patients who will develop arrhythmias both in the immediate and late postoperative periods. The appearance of an immediate postoperative arrhythmia also predicts the subsequent development of late arrhythmias. Recognition of these predictors may facilitate monitoring and therapy of such patients.

Control of late postoperative ventricular arrhythmias with phenytoin in young patients

Ventricular arrhythmias probably initiate the events leading to sudden death in patients who have recovered uneventfully from surgery for congenital heart disease. It is therefore recommended that antiarrhythmic therapy be given to all patients who have had surgery for congenital heart defects and who have ventricular arrhythmias found in a routine electrocardiogram taken after the immediate postoperative period. The response of ventricular arrhythmias to treatment was studied in six ambulatory patients aged 7 to 27 years (mean 16.5) who had had surgery a mean of 10.7 years before the arrhythmia was recognized. Four patients had unsatisfactory repair of the congenital defect; the two other patients had only a palliative operation. Each patient's electrocardiogram was monitored continually by tape recording. Each received phenytoin, 3.75 mg/kg body weight, every 6 hours for four doses, then 1.9 mg/kg every 6 hours until the serum concentration of phenytoin was 15 to 20 μg/ml. This serum concentration was maintained with the daily administration of 2.5 to 3 mg/kg every 12 hours. In the 24 hours before treatment, two patients had ventricular tachycardia, two had paired premature ventricular complexes and two had 10 or more single premature ventricular complexes/hour. After treatment, all patients had “effective control” (one or less premature ventricular complex/hour for 12 consecutive hours). This control was achieved with phenytoin in five patients, but one patient required the addition of disopyramide (2 mg/kg every 6 hours). All five patients undergoing a treadmill test before treatment had premature ventricular complexes during or after exercise; after treatment, only one had premature ventricular complexes after exercise. The patient who required two drugs was unable to perform a treadmill test. The mean effective serum phenytoin concentration, 15.7 μg/ml (range 8.5 to 20.0), was reached at a mean time of 61.2 hours (range 42 to 80) after the start of phenytoin therapy. Ataxia occurred in two patients with serum phenytoin concentrations of 16 and 20 μg, but not in the other four, three of whom had serum concentrations greater than 20 μg/ml. Echocardiographic, hematopoletic, hepatic and renal function indexes remained constant with treatment. It is concluded that (1) phenytoin suppressed ventricular arrhythmias in six children and young adults after surgery for congenital heart disease; (2) the effective serum concentration of phenytoin was approximately 15 μg/ml, but varied widely; and (3) this concentration was achieved within 48 to 72 hours when an oral loading dose was administered.