Preoperative Sinus Rhythm Research Articles

Comparing the outcome of on-pump versus off-pump coronary artery bypass grafting in patients with preoperative atrial fibrillation

Around 5-15% of patients undergoing coronary artery bypass grafting (CABG) suffer from preoperative/pre-existing atrial fibrillation (PAF). This is a benign arrhythmia but can affect the outcome of the surgery. The aim of this study was to assess the effect of PAF on the immediate postoperative course of patients undergoing on-pump (ONCAB) vs. off-pump (OPCAB) CABG. Over a 10-year period, data were prospectively entered into the database of our institution. A total of 10,461 patients underwent CABG, of whom 477 (4.6%) were in PAF. We analyzed these patients in two separate groups: group A (n=310) who underwent ONCAB and group B (n=167) who underwent OPCAB. After 4:1 propensity matching and adjusting for the preoperative and operative characteristics of these two groups with patients in SR (sinus rhythm), early, mid- and long-term outcomes of PAF patients were analyzed. After adjusting for preoperative characteristics, postoperative complications were significantly higher in patients who had ONCAB when there was PAF compared to those in SR (P<0.001). In the OPCAB patients, on the other hand, there was no statistically significant difference in the postoperative complications between the patients with preoperative SR or PAF. In-hospital and short-term mortality were no different in the PAF group undergoing OPCAB compared to those in SR; however, the mid- and long-term survival rates in PAF patients who underwent OPCAB/ONCAB were worse compared than was seen in SR. PAF is associated with a higher incidence of postoperative complications. Our results have demonstrated that patients in PAF undergoing ONCAB are more susceptible to the postoperative complications compared to those in SR. However, there were no differences in mid- and long-term outcomes.

Atrial fibrillation postcardiac surgery: a common but a morbid complication☆☆☆

Despite all the advances in cardiac surgery, atrial fibrillation (AF) remains a common postoperative complication with unclear predisposing factors. Postoperative AF is often a short-lived and a self-limiting condition, but can result in debilitating and even lethal consequences. The aim of this study is to assess the effect of AF on patients postcardiac surgery. In this retrospective study, we prospectively reviewed patient data for our institution for a 10-year period; a total of 17,379 patients with preoperative sinus rhythm (SR) who underwent cardiac surgery were included, of which 4984 (28.7%) had developed postoperative AF for any length of time. After propensity matching for the preoperative characteristics between the two groups; the group with AF and the group who remained in SR, postoperative complications, in-hospital mortality, mid-term survival rate (five years), and long-term survival rate (10 years) were compared. Before and after adjusting for the preoperative characteristics and type of the operation, postoperative complications, such as renal failure, surgical wound infection, stroke and myocardial infarction were significantly higher in the AF group compared to the SR group (P < 0.001). Inotropic support, use of intra-aortic balloon pump, and ventilation time were also considerably higher in the AF patients (P < 0.001). In-hospital mortality was also higher in the AF group. Likewise, 30-day, mid-term and long-term mortality rates were found to be considerably higher in the AF group. Despite all the modern anti-arrhythmic drugs, the incidence of AF remains unchanged. Patients who develop AF postcardiac surgery show a significantly worse outcome compared to those without AF. This study also highlights the importance of anticoagulation in AF to prevent the devastating consequences as a result of a cerebral stroke. We believe that not only immediate treatment of AF postoperatively should be implemented, but also measures should be taken to identify the risk factors of AF and to prevent AF postcardiac surgery.

The Impact of New-Onset Postoperative Atrial Fibrillation on Mortality After Coronary Artery Bypass Grafting

New-onset postoperative atrial fibrillation (POAF) is a frequent rhythm disturbance after coronary artery bypass grafting (CABG). This study investigated the independent effect of POAF on early and late mortality after isolated CABG. Data of patients who consecutively underwent isolated CABG between January 2003 and December 2007 were prospectively collected. The analysis included 5098 patients with preoperative sinus rhythm and no history of atrial fibrillation. Logistic regression analysis for early mortality and Cox regression analysis for late mortality were performed. Propensity score matching was performed to eliminate the effect of confounders. Median follow-up was 2.5 years. POAF was documented in 1122 patients (22.0%). Early mortality was more frequent in POAF patients (3.1%) vs non-POAF patients (1.6%, p = 0.002), but multivariate logistic regression analysis could not identify POAF as an independent predictor of early mortality (p = 0.169). This outcome did not change after adjusting for quintiles of the propensity score of POAF (p = 0.100). Multivariate Cox proportional hazard analyses demonstrated POAF was an independent predictor of overall and late mortality with hazard ratios of 1.35 (p = 0.012 and p = 0.039, respectively). Analyses after propensity score matching showed that patients with POAF had similar hazard ratios of 1.36 for overall mortality and 1.34 for late mortality (p = 0.009 and p = 0.042, respectively). POAF is an independent predictor of overall and late mortality after isolated CABG but not of early mortality.

The impact of preoperative atrial fibrillation on early and late mortality after coronary artery bypass grafting

There are still doubts on the effect of preoperative atrial fibrillation (AF) on early and late mortality after coronary artery bypass grafting (CABG). This retrospective study demonstrates the effects of preoperative AF on the short-term and long-term survival after CABG. We retrospectively analysed the data of 10626 patients who underwent CABG between January 1998 and December 2007. The data of 221 patients with a history of preoperative AF (2.5%) and 8631 patients with preoperative sinus rhythm were eligible for analysis. Survival of these patient groups was compared to survival of age- and sex-matched groups of the Dutch general population. Mean follow-up duration was 4.6 + or - 2.9 years. Multivariate logistic regression analysis showed preoperative AF to be an independent risk factor for early mortality after CABG, with an odds ratio of 2.06 (95% confidence interval (CI): 1.08-3.95; P=0.029). Multivariate Cox proportional hazard analysis revealed that preoperative AF is an independent risk factor for late mortality after CABG, with a hazard ratio (HR) of 1.67 (95% CI: 1.21-2.31; P=0.002). Using propensity score matching, AF was also an independent risk factor for late mortality after CABG, with an HR of 2.77 (95% CI: 1.6-4.79; P<0.001). In comparison with the general Dutch population, patients with preoperative AF who undergo CABG have a worse long-term survival, while patients with preoperative sinus rhythm experience a better survival. Preoperative AF is an independent risk factor for early and late mortality after first-time elective CABG.

Atrial Na,K-ATPase Increase and Potassium Dysregulation Accentuate the Risk of Postoperative Atrial Fibrillation

Background: Postoperative atrial fibrillation is a common complication to cardiac surgery. Na,K-ATPase is of major importance for the resting membrane potential and action potential. The purpose of the present study was to evaluate the importance of Na,K-ATPase concentrations in human atrial biopsies and plasma potassium concentrations for the development of atrial fibrillation. Methods: Atrial myocardial biopsies were obtained from 67 patients undergoing open chest cardiac surgery. Na,K-ATPase was quantified using vanadate-facilitated ³H-ouabain binding. Plasma potassium concentration was measured with ion-selective electrode. Results: In patients with preoperative sinus rhythm, ³H-ouabain-binding site concentration was 16% higher in patients developing postoperative atrial fibrillation compared to patients maintaining sinus rhythm [302 ± 15 pmol/g wet weight (n = 20) vs. 261 ± 11 mmol/g wet weight (n = 33), p = 0.03]. Also with multivariable analysis, ³H-ouabain-binding site concentration was significantly associated with the development of atrial fibrillation. High increase in plasma potassium concentration during the perioperative period and surgery was associated with postoperative atrial fibrillation. Conclusions: The present study supports the increasing evidence of dysregulation of the potassium homeostasis as an important factor in the development of cardiac arrhythmias. High atrial Na,K-ATPase and sudden plasma potassium concentration increase may contribute to precipitate atrial fibrillation.

Heat Shock Protein70: A New Marker for Subsequent Atrial Fibrillation Development?

Atrial fibrillation (AF) is a common arrhythmia, after cardiac surgery, and it is associated with a twofold increase in cardiovascular mortality and morbidity. Reperfusion injury and inflammation associated with cardiac surgery are thought to be involved in its pathogenesis. Heat shock proteins (HSPs) are a family of chaperone proteins which assist in preservation of cellular integrity by maintaining proteins in their correctly folded state. The aim of this study was to investigate pre-postoperative heat shock protein70 (HSP70) and high-sensitivity C-reactive protein in serum from patients in preoperative sinus rhythm. We prospectively screened 45 consecutive patients admitted to the hospital for elective coronary artery bypass surgery (CABG). Electrocardiogram characteristics and cardiovascular risk profile were documented. Pre- and postoperative blood samples were collected. HSP70 value was 8.9 +/- 4.8 ng/mL in Group A (study group) preoperatively and decreased to 7.7 +/- 7.0 ng/mL postoperatively. In contrast, preoperative value of HSP70 was 4.2 +/- 2.2 ng/mL and decreased to 2.7 +/- 2.6 ng/mL postoperatively in Group B (control group). Statistical analysis showed significant difference regarding preoperative HSP70 levels in Group A compared to Group B. To our knowledge, with this study, the association of pre- and postoperative circulating HSP70 with postoperative AF was demonstrated for the first time.

The Role of Inflammation in Atrial Fibrillation following Open Heart Surgery

This study investigated the role of systemic inflammation in the development of atrial fibrillation (AF) after coronary artery bypass grafting (CABG). CABG was performed using cardiopulmonary bypass in 77 patients. Pre-operative AF was present in six patients (7.8%) and postoperative AF developed in 13 (18.3%) of the 71 patients with pre-operative sinus rhythm. Post-operative mediastinal drainage was significantly increased in patients with post-operative AF compared with those with sinus rhythm. Plasma E-selectin, P-selectin and vascular cell adhesion molecule levels were not significantly different between patients with pre- and post-operative sinus rhythm, those with pre-operative sinus rhythm and post-operative AF, and those with pre- and post-operative AF. There were significant differences between pre- and post-operative C-reactive protein, interleukin (IL)-6 and IL-10 levels within all three groups, but no differences in these parameters between the groups. Thus, in all groups there were significant alterations in mediators indicative of systemic inflammation following CABG, but comparisons between the groups revealed no differences predictive of AF.

The outcomes of operations for 539 patients with Ebstein anomaly

Our objective was to review the long-term outcomes of patients with Ebstein anomaly who underwent cardiac surgery at our institution. Patient records were reviewed, and all patients were mailed a medical questionnaire or contacted by means of telephone. Patients who had pulmonary atresia with an intact ventricular septum, complex conotruncal abnormalities, and atrioventricular discordance with ventriculoarterial discordance were excluded. From April 1, 1972, to January 1, 2006, 539 patients with Ebstein anomaly had 604 cardiac operations. The mean age at the time of the initial operation at our institution was 24 years (range, 8 days-79 years). Three hundred seventeen of the patients were female. One hundred forty-three (26.5%) patients had a prior invasive cardiac procedure before coming to Mayo Clinic. At the time of the first operation at Mayo Clinic, 182 patients had tricuspid valve repair, and 337 had tricuspid valve replacement. The 30-day mortality was 5.9% for the entire cohort (2.7% after 2001). Late survival was 84.7% at 10 years and 71.2% at 20 years. In a multivariate analysis of overall mortality for the patients' first operation at Mayo Clinic, increased hematocrit values, pulmonary valve stenosis, tricuspid valve replacement, absence of ablation of an accessory pathway, miscellaneous arrhythmia procedure, branch pulmonary artery enlargement, need for mechanical support postoperatively, emergency chest opening in the intensive care unit, and absence of sinus rhythm at dismissal were all predictive of mortality. When only preoperative characteristics were included, increased hematocrit values, mitral valve regurgitation requiring surgical intervention, prior cardiac procedure, and moderate-to-severe to severe reduction in right ventricular systolic function were associated with mortality. Preoperative sinus rhythm and an accessory pathway were associated with survival. Patients rated their health as excellent or good (New York Heart Association class I or II) in 83% of surveys returned. Ebstein anomaly can be surgically treated with low perioperative mortality. Both tricuspid valve repair and tricuspid valve replacement are associated with good long-term survival. Risk factors for poorer outcome included right, and/or left ventricular systolic dysfunction; increased hemoglobin/hematocrit values; male sex; right ventricular outflow tract obstruction; or hypoplastic pulmonary arteries.

Early and Late Survival After Surgical Revascularization for Ischemic Ventricular Fibrillation/Tachycardia

Ischemic ventricular fibrillation/tachycardia (VF/VT) treated by myocardial revascularization, often with an implanted cardioverter defibrillator, prevents sudden cardiac death. Early series have suggested that recurrent VF/VT threatens survival even after treatment. As late outcome is unknown, we sought to determine if the early survival benefit is sustained. From January 1999 through January 2007, 93 consecutive patients (75 male, 81%) presented with ischemic VF/VT; 21% survived cardiac arrest and underwent coronary artery bypass graft surgery at our institution. We analyzed their early and late survival. Median age was 66 years (range, 44 to 88). Clinical presentation included class III/IV angina (46%), controlled heart failure (43%), prior myocardial infarction (68%), left ventricular ejection fraction less than 0.30 (23%) and 0.30 to 0.50 (35%), left main stem disease (24%), and triple-vessel disease (67%). Surgical revascularization, mostly nonelective (urgent 73%, emergency 7%), was combined with aortic valve replacement in 5 patients and left ventricular pseudoaneurysm repair in 3. Ischemic territories and mean number of diseased coronaries (2.6) corresponded to the grafted territories and average number of grafts (2.5). Operative mortality was 6.5% (n = 6, median EuroSCORE [European System for Cardiac Operative Risk Evaluation] predicted mortality 9). Recurrent VF/VT occurred early postoperatively in 21 patients (24%). All patients had electrophysiologic studies postoperatively and 40% received an implanted cardioverter defibrillator. Of 12 late deaths (16%) at follow-up extending to 8 years, 4 (33%) were due to cardiac causes. Five-year survival was 88%, equivalent to that (83% to 85%) reported for patients with sinus rhythm preoperatively. Complete myocardial revascularization for ischemic VF/VT yields excellent early and late results; 5-year survival is comparable to that of patients with preoperative sinus rhythm.

Factors Determining Early Left Atrial Reverse Remodeling After Mitral Valve Surgery

This study aimed to investigate the factors determining early left atrial (LA) reverse remodeling after mitral valve (MV) surgery. The left atrium is frequently dilated in patients with mitral stenosis (MS) or mitral regurgitation (MR). MV surgery usually results in LA volume reduction. However, the factors associated with LA reverse remodeling after MV surgery are not clearly defined. One hundred thirty-eight patients (51 men, 87 women; mean age, 53 years) underwent transthoracic echocardiography before and after MV surgery. Maximal LA volume was measured using the prolate ellipsoid model. The percentage of LA volume change was calculated. The patients were grouped according to age (<50 vs >or=50 years), predominant lesion (pure MR vs some degree of MS), type of surgery (MV repair vs MV replacement), and preoperative rhythm (sinus rhythm vs atrial fibrillation). LA volume decreased from 147+/-93 to 103+/-43 ml (p<0.001) after surgery. LA reverse remodeling was more prominent in patients who were <50 years old (percentage of LA volume change -31.2+/-17.4 vs -18.4+/-19.2, p<0.001), had pure MR (percentage of LA volume change -30.4+/-18.6 vs -17.3+/-18.2, p<0.001), and had a preoperative sinus rhythm (percentage of LA volume change -28.5+/-17.7 vs -20.5+/-20.0, p=0.019). In conclusion, on stepwise multiple regression analysis, preoperative LA volume, predominant lesion, age, and cardiac rhythm were significant predictors of LA reverse remodeling. A larger preoperative LA volume, MR rather than MS, younger age at the time of surgery, and sinus rhythm were important predictors of LA reverse remodeling after MV surgery.

Does preoperative atrial fibrillation influence early and late outcomes of coronary artery bypass grafting?

The study objective was to describe the independent effect of preoperative atrial fibrillation on the outcome of coronary artery bypass grafting, including the causes of death (cardiac vs noncardiac). We analyzed the outcome of patients with preoperative atrial fibrillation who underwent on-pump coronary artery bypass grafting between 1993 and 2002 and compared them with matched controls in sinus rhythm; matching variables were age, gender, ejection fraction, and numbers of diseased coronary arteries and distal anastomoses. Direct patient follow-up focused on late complications and reinterventions, and we investigated causes for all deaths. Operative mortality (1.6% vs 1.9%, P = .79) was similar in patients with preoperative atrial fibrillation (n = 257) compared with patients in sinus rhythm (n = 269). The patients with atrial fibrillation had longer hospital stays (9 +/- 6 days vs 8 +/- 6 days, P = .0008) and a trend to more frequent early readmissions (13% vs 9%, P = .08). During follow-up (median 6.7 years, maximum 12 years), late hospital admission was more frequent in patients with atrial fibrillation (59% vs 31%, P < .0001). Risk of late mortality (all causes) in patients with atrial fibrillation was increased by 40% compared with patients in sinus rhythm (P = 0.02), and the late cardiac death rate in the atrial fibrillation group was 2.8 times that of the sinus rhythm group (P = .0004). Major adverse cardiac events occurred in 70% of patients with preoperative atrial fibrillation compared with 52% of patients in preoperative sinus rhythm (P < .0001). Subsequent rhythm-related intervention, including pacemaker implantations, was more common in the atrial fibrillation group (relative risk = 2.1, P = .0027). Uncorrected preoperative atrial fibrillation in patients undergoing coronary artery bypass grafting is associated with increased late cardiac morbidity and mortality and poor long-term survival. These data support consideration of atrial fibrillation surgery at the time of coronary artery bypass grafting.

Prognostic Implications of Preoperative Atrial Fibrillation in Patients Undergoing Aortic Valve Replacement: Is There an Argument for Concomitant Arrhythmia Surgery?

The prognostic significance of preoperative atrial fibrillation (AF) at the time of aortic valve replacement is unknown, as is the potential role for concomitant arrhythmia surgery. We performed a cohort comparison of patients with preoperative AF (n = 129) and preoperative sinus rhythm (SR, n = 252) undergoing aortic valve surgery between 1993 and 2002; patients were matched for age, gender, and left ventricular ejection fraction. Follow-up (mean interval, 4.5 years) was 98% complete. Primary endpoints were late cardiac and all-cause mortality, as well as major adverse cardiac or cerebrovascular event. Patients with preoperative AF presented with more severe congestive heart failure (p = 0.03) and more often had significant tricuspid regurgitation (p = 0.01) preoperatively. They also had worse late survival (risk ratio [RR] for death = 1.5, p = 0.03) with 1-, 5-, and 7-year survival rates substantially reduced at 94%, 87%, and 50%, respectively, for those in AF versus 98%, 90%, and 61% for patients in sinus rhythm preoperatively. Individuals in AF had a greater probability of subsequent rhythm-related intervention (RR = 4.7, p = 0.0002), and more frequently developed congestive heart failure (25% vs 10%, p = 0.005) and stroke (16% vs 5%, p = 0.005). By multivariable analysis, preoperative AF was an independent predictor of late adverse cardiac and cerebrovascular events, but not late death. Performance of concomitant arrhythmia surgery in patients undergoing aortic valve surgery may reduce late morbidity; however, its potential impact on late mortality in this high-risk subset of patients remains unclear.

Conversion to sinus rhythm does not improve long-term survival after valve surgery: insights from a 20-year follow-up study☆

Atrial fibrillation (AF) is frequently associated with valvular heart disease and a common complication of valve surgery. Its contribution to long-term mortality and morbidity remains debated. Our objective was to determine the impact of AF on long-term mortality and embolic complications after valvular surgery and the benefit of conversion to sinus rhythm. This may provide insight to the clinical advantages of surgical anti-AF procedures. Data concerning rhythm status, mortality and embolic complications were prospectively collected for 5466 patients with valve surgery. Patients had surgery between 1979 and 2003. Follow-up was complete and all patients had a yearly EKG. Patients with preoperative AF had poorer long-term survival than patients without preoperative AF (20-year survival 23.7 and 33.4%, respectively, P<0.0001). However, preoperative AF was not an independent risk factor of long-term mortality (HR=1.04, P=0.6). In patients with preoperative sinus rhythm, postoperative development of AF had an impact on long-term mortality (HR=1.46, P=0.0012). In patients with preoperative AF, postoperative rhythm did not influence mortality when adjusted for other variables (AF vs. sinus rhythm, HR=1.07, P=0.5709). Mitral valve surgery (HR=1.55, P=0.0270) but not preoperative or postoperative AF had a significant impact on the advent of embolic complications. The conversion to sinus rhythm did not improve long-term survival or reduce the incidence of embolic complications after valve surgery. Patients with preoperative AF had poorer survival than patients without preoperative AF. AF may be a marker of advanced disease in these patients.

Pre-operative atrial fibrillation as the key determinant of outcome of mitral valve repair for degenerative mitral regurgitation

To examine the impact of pre-operative atrial fibrillation (AF) on the outcome of mitral valve repair (MVR) for degenerative mitral regurgitation (MR). Among 392 patients with moderate to severe MR who underwent MVR between 1991 and 2002, 283 patients with isolated degenerative MR were followed for 4.7+/-3.3 years. Of 27 deaths, nine were due to cardioembolic events and four were due to left ventricular (LV) dysfunction. When compared with patients with pre-operative AF, those with sinus rhythm (SR) had better survival (96+/-2.1 vs. 87+/-3.2% at 5 years, P=0.002) and higher cardiac event-free rates (96+/-2.0 vs. 75+/-4.4% at 5 years, P<0.001). In patients with pre-operative SR, observed and expected survival were similar (P=0.811). Cox multivariable regression analysis confirmed AF [P=0.027, adjusted hazard ratio (AHR) 2.9] and age as independently predictive of survival, and AF (P=0.002, AHR 3.1), New York Heart Association Class, and LV fractional shortening as independently predictive of cardiac event. Death due to LV dysfunction was not frequent and cardioembolic events due to AF were the leading cause for cardiac death. Pre-operative AF became a strong independent predictor of survival and morbidity. Patients with pre-operative SR had excellent prognosis. The benefits of preventing cardioembolic events due to AF validate the indication of MVR for patients with high risk for AF.

Atrijalna septalna elektrostimulacija u prevenciji atrijalne fibrilacije nakon koronarnog arterijskog premošćavanja kod visokorizičnih bolesnika

Atrial fibrilation is the most often heart rhythm disorder and the most often cause of hospitalization due to the heart rhythm disorder. The incidence of atrial fibrillation after coronary artery bypass graft varies from 25 to 30%, while it significantly grows if along with the existing operation, there is a significant valvulary failure, which is resolved with the operation. So far poor results of atrial fibrillation treatment after coronary arterial bypass graft require new approaches in resolving of this problem. The aim of the work was to examine the efficiency of interatrial pacing in prevention of the atrial fibrillation after coronary arterial bypass graft in the high-risk patients. The patients were separated in two groups: those who were applied atrial septal pacing (group A) and those without pacing (group B). There were 30 patients in each group. The conditions for including were: over 60 years of age, right coronary artery stenosis higher than 50%, preoperative sinus rhythm and ejection fraction of the left ventricle lower than 40%. The patients in Group A had epicardial electrode positioned during, the operation in the Cox's triangle and the stimulation was performed with frequency 10% higher than the spontaneous, up to maximum 110 per minute. The patients in the Group V had only the electrode positioned, but stimulation was not performed. The stimulation commenced on the fourth hour of the postoperative treatment and lasted continuously for the following 96 hours. The results have shown statistically significantly higher incidence of atrial fibrillation in the group without pacing, due to which the hospitalization was significantly longer thus also the cost of the treatment. In the high-risk patients atrial septal pacing is safe and efficient in prevention of atrial fibrillation after coronary arterial bypass graft.

Early and late arrhythmias in patients in preoperative sinus rhythm submitted to mitral valve surgery through the superior septal approach

Background It has been hypothesized that the use of the superior septal approach to the mitral valve can lead to postoperative loss of sinus rhythm. This study was undertaken to evaluate the early and mid-term alterations of the cardiac rhythm in patients with preoperative sinus rhythm (SR) submitted to mitral valve surgery through the superior septal approach Methods Seventy-five cases in preoperative SR submitted to primary isolated mitral valve surgery through the superior septal approach constitute the study population. All patients underwent 12-lead electrocardiography on admission, every day after surgery until discharge and every year during the follow-up period. Results On admission in the intensive care unit, 46 cases maintained their preoperative rhythm, whereas 18 developed a junctional rhythm (JR) and 7 had a first- or second-degree atrio-ventricular block (AVB). Four cases arrived in the unit in atrial fibrillation (AF). On the first postoperative day, these proportions were substantially unchanged, with the only exception being a slight increase in the number of patients in AF. The day before discharge, only 35 of the 74 surviving cases maintained the preoperative SR, whereas 13 developed AF, 10 were in JR, and 16 were in AVB. During the follow-up period (mean, 26 ± 14 months), the majority of cases (47/74) regained SR; 11 patients had AVB, 3 were in JR, and the remaining 13 were in AF. Conclusions The use of the superior septal approach for mitral valve procedures in patients in preoperative SR is associated with minor, transient cardiac rhythm disturbances.

Risk factors associated with new onset tachyarrhythmias after cardiac surgery – a retrospective analysis

Tachyarrhythmias (TA) represent a frequent and serious problem after cardiac surgery. We retrospectively analyzed 987 cardiac surgery patients admitted to a surgical intensive care unit between 1996 and 1999 to assess incidence and risk factors associated with development of postoperative TA in the intensive care unit. TA (n=149) were defined as non-sinus rhythm with a heart rate (HR) > or =100 bpm in patients with preoperative sinus rhythm or as heart rate > or =130 bpm in patients with preoperative atrial fibrillation. A total of 787 patients served as controls (C). Demographic, premorbidity and perioperative data, admission SAPS and MODS-score, presence of clinical syndromes systemic inflammatory response syndrome (SIRS) and sepsis were univariately compared between groups. For prediction of independent risk factors for TA-development two multiple logistic regression models were finally established. Concerning TA, atrial fibrillation and flutter (76%) were observed most frequently, followed by paroxysmal supraventricular tachycardia (15%) and ventricular tachycardia/fibrillation (11%). Age, a history or presence of congestive heart failure, development of SIRS and sepsis, severity of multiple organ dysfunction syndrome and in particular severity of cardiovascular failure proved to be independent risk factors for development of TA. In cardiac surgery patients, age, a history or presence of congestive heart failure, postoperative development of a systemic inflammatory response syndrome or sepsis and the severity of multiple organ function syndrome were independent predictors for development of TA in the intensive care unit. The association of severity of cardiovascular dysfunction with TA strongly suggests a causal relationship between catecholamine therapy and TA-development.

Sinus node function after mitral valve surgery using the superior septal approach

Background. Sinus node function after the superior septal approach (SSA) in mitral valve surgery is controversial. We assessed sinus node function after this approach based on electrophysiological examinations and electrocardiographic change. Methods. Forty-six patients underwent successful mitral valve surgery via the SSA. Preoperatively, 25 patients were in atrial fibrillation (AF), 20 were in normal sinus rhythm (SR), and 1 patient was paced. Thirteen patients who demonstrated no sinus node dysfunction preoperatively underwent postoperative electrophysiological studies. Peripostoperative cardiac rhythm was monitored using a portable four-lead electrocardiograph, and late cardiac rhythm was examined using standard 12-lead electrocardiography in the outpatient clinic. Results. Twelve of 20 patients with preoperative SR experienced early postoperative supraventricular arrhythmias, but all spontaneously recovered SR. Electrophysiological studies revealed a basic cycle length of 767 ± 74 ms, sinoatrial conduction time of 72 ± 34 ms, sinus node recovery time of 1,119 ± 139 ms, and corrected sinus node recovery time of 349 ± 114 ms, thus demonstrating a lack of sinus node dysfunction. During the postoperative period (34 ± 24 months), 2 of the 20 patients with preoperative SR developed persistent AF, and 3 of the 25 patients with preoperative AF achieved normal SR. Conclusions. The SSA does not appear to cause long-term adverse effects on sinus node function, although temporary effects may occur.

Combined superior-transseptal approach versus conventional approach for mitral valve surgery.

This study was designed to evaluate the safety and effectiveness of the combined superior-transseptal approach for mitral valve surgery. We compared the preoperative status, operative factors, and postoperative outcomes among patients having mitral valve operations with three atrial incisions. The incisions were transseptal (n = 40), combined superior-transseptal (n = 33), and left atrial (n = 22). The cardiopulmonary bypass time and cross-clamp time were significantly higher in the superior-transseptal group compared with the transseptal group. No significant difference in blood loss was found among the three groups. The incidence of sinus node dysfunction in the early postoperative period was more common in the superior-transseptal group. The maintenance of sinus rhythm at the mid-term follow-up in patients with preoperative sinus rhythm was not significantly different among the three groups. On the other hand, a few patients in the superior-transseptal and transseptal groups with the preoperative sinus rhythm developed sick sinus syndrome requiring permanent pacemaker implantation. The use of the combined superior-transseptal approach was safe and effective, and was not associated with a higher incidence of rhythm disturbance. Because this approach provided an optimal exposure of the mitral valve and subvalvular apparatus, it has been positively adopted for use in patients undergoing complex and difficult mitral valve operation. To use this approach for patients undergoing mitral valve surgery through this approach, however, further follow-up study of the sinus node function is necessary.

Mitral valve surgery and atrial fibrillation: is atrial fibrillation surgery also needed?

Atrial fibrillation (AF) persisting after mitral valve surgery reduces survival due to heart failure and thrombo-embolisms, and impairs quality of life. Arrhythmia surgery for AF shows today very satisfying results and therefore mitral valve surgery with AF surgery appears appealing. This study explores whether combined surgery in view of today's results of mitral valve surgery is indicated. An outcome analysis of the arrhythmia outcome of patients undergoing exclusive mitral valve surgery with or without tricuspid repair was done. Preoperative baseline characteristics including arrhythmia pattern, surgical methods and follow-up findings were reviewed. Postoperative management of AF was not protocolized. Between 1990 and 1993, 162 consecutive patients underwent mitral valve surgery; follow-up was a mean of 3.3+/-1.9 years. In-hospital and late mortality were 1 and 9%, respectively. Sinus rhythm was preserved in 40 of 57 (70%) patients with preoperative sinus rhythm whereas AF persisted in 58 of 68 (85%) of patients with preoperative chronic AF (>1 year present). Sinus rhythm without AF was observed in 10 of 29 (34%) patients with preoperative paroxysmal AF. The 4-year Kaplan-Meier survival did not differ between patients with preoperative sinus rhythm (95.2%), paroxysmal AF (89.2%) and chronic AF (82.9%) but AF persisting after surgery tended to determine survival (P=0.05). Gender, age and right ventricular pressure and tricuspid valve repair were risk factors for postoperative recurrence of AF in patients with sinus rhythm at discharge, relative risk 0.35, 1.06, 1. 04 and 2.9, respectively. Current mitral valve surgery with or without tricuspid valve repair does not eliminate preoperative paroxysmal or chronic AF. Secondly, because preoperative AF did not determine survival after mitral valve surgery, whereas postoperatively persisting AF was weakly associated with survival, atrial arrhythmia surgery primarily aims to reduce morbidity due to AF. Some characteristics can identify patients with increased propensity for persisting AF after surgery. Randomized studies of AF surgery are needed to identify suitable candidates for combined surgery.