Effect of mitral valve repair/replacement surgery on atrial arrhythmia behavior

BACKGROUND AND AIMS OF THE STUDY: Few data have been published on the effects of mitral valve surgery on atrial rhythm. The study aims were to determine the effects of surgery on: (i) persistence of atrial fibrillation (AF); (ii) measures of left atrial and ventricular dimensions; and (iii) ECG P-wave duration. METHODS: A retrospective case-note review of 92 patients with chronic mitral regurgitation was undertaken. Variables determined included prevalence and duration of AF; incidence of new-onset or persistence of AF after surgery; rhythm changes in relation to age, gender, left atrial and ventricular dimensions and function, anti-arrhythmic drug usage and ECG P-wave duration in sinus rhythm prior to surgery. RESULTS: Only 4/47 (8.5%) patients with any history of AF before surgery were in sinus rhythm at six months after surgery. All 28 patients with persistent AF for >12 months and 41/45 (91%) in sinus rhythm before surgery retained these rhythms after surgery. The left atrial dimension was decreased after surgery, in the whole group (51.3 +/- 9.0 versus 48.4 +/- 9.5 mm; p = 0.011) and in the subgroup in sinus rhythm, but not in the subgroup in AF. The left ventricular end-diastolic dimension decreased in the group as a whole (60.6 +/- 6.2 versus 53.0 +/- 8.7 mm; p = 0.0001) and in both subgroups after surgery. In 24 patients with 12- lead ECGs in sinus rhythm before and three months after surgery, P-wave duration remained unchanged. However, this measure decreased in the 18 patients in sinus rhythm consistently, but increased in the six patients continuing to have paroxysmal AF after surgery. CONCLUSION: Mitral valve surgery alone restored sinus rhythm in only 8.5% of patients with any previous history of AF. Concomitant anti-arrhythmic procedures should be considered for all patients with AF who undergo mitral valve surgery.     

Effect of atrial fibrillation on the dynamics of mitral annular area

BACKGROUND AND AIMS OF THE STUDY: The mitral annulus shows dynamic changes in shape and size during the cardiac cycle. A smaller size in end-diastole is attributed to the sphincteric action of atrial systole, and this may be important for functional integrity of the mitral valve. However, the effect of atrial fibrillation (AF) on dynamic changes in mitral annular size in humans is not known. METHODS: Mitral annular diameters in apical four- and two-chamber views were measured using echocardiography in 25 patients in atrial fibrillation, and in 37 subjects in normal sinus rhythm at mid-diastole, end-diastole and end-systole. Mitral annular area was computed assuming elliptical geometry. RESULTS: Patients in sinus rhythm showed a significant increase in mitral annular area of 25.9 +/- 12.8% with ventricular systole compared to its area in end-diastole (p < 0.0001), and a 10.5 +/- 8.4% reduction with atrial systole compared to mid-diastole (p < 0.001). Patients in AF had larger mitral annuli which showed non-significant changes in size between these three phases of the cardiac cycle. Percent reduction in mitral annular area in the latter half of diastole correlated significantly with left atrial (LA) diameter (r = -0.54, p < 0.0001), LA volume (r = -0.50, p < 0.0001), left ventricular (LV) fractional shortening (r = 0.37, p = 0.0036), mitral annular area in mid-diastole (r = -0.41, p = 0.0011) and mitral annular area in end-diastole (r = -0.64, p < 0.0001). That is, atrial sphincteric action on the mitral annulus was less in the presence of larger left atrium or the mitral annulus. Stepwise multiple regression analysis showed rhythm and mitral annular size to be independent predictors of dynamic changes in mitral annular area. CONCLUSION: It is concluded that AF blunts or eliminates the phasic changes in mitral annular size during the cardiac cycle with loss of its presystolic sphincteric action; this may have implications in the genesis and surgical correction of mitral regurgitation.     

Plasma concentration of atrial natriuretic peptide is related to the duration of atrial fibrillation in patients with advanced heart failure

BACKGROUND: Plasma concentration of atrial natriuretic peptide (ANP) is elevated in patients with atrial fibrillation (AF) and in patients with chronic heart failure (CHF).Aim. To assess ANP level in patients with permanent AF and advanced CHF. METHODS: The study group consisted of 41 patients (27 males, mean age 62+/-8 years) with AF of a mean duration of 8.8 months. Twenty six (63%) patients were in NYHA class II, and 15 (37%) - in NYHA class III or IV. All patients underwent clinical and echocardiographic evaluation as well as ANP plasma concentration assessment. Multiple regression analysis was used to identify factors which determine ANP plasma concentration. RESULTS: Mean ANP plasma concentration was 52.4+/-22.7 pg/ml in the whole study group; 38.6+/-10.8 pg/ml in NYHA class II patients and 74.9+/-18.7 pg/ml in NYHA class III-IV subjects (p<0.0001). Among echocardiographic parameters, patients with NYHA class III or IV had significantly lower left ventricular ejection fraction and greater left atrial volume than patients with NYHA class II (32% versus 56%, p<0.0001 and 101.0+/-23.8 cm(3) versus 83.4+/-16.1 cm(3), p<0.006, respectively). Multiple regression analysis revealed a significant negative correlation between AF duration and ANP level (p=0.0013) in a group of patients with NYHA class III or IV and identified AF duration as an independent predictor of ANP plasma concentration in this group of patients. CONCLUSIONS: ANP plasma concentration in patients with persistent AF and advanced CHF is determined by AF duration - the longer the AF duration the lower the ANP level.     

The predictive value of chronic atrial fibrillation for the short- and long-term outcome after percutaneous mitral balloon valvotomy

BACKGROUND AND AIM OF THE STUDY: The predictive value of chronic atrial fibrillation (AF) before percutaneous mitral balloon valvotomy (PMBV) is still under discussion. The effect of the duration of chronic AF on short- or long-term results is not known. Therefore, we analyzed the predictive value of pre-procedural chronic AF and the duration of this rhythm disturbance for short- and long-term outcome after PMBV in patients with mitral valve stenosis. METHODS: A total of 140 PMBV procedures was performed in 137 patients with severe mitral stenosis. Sixty-three patients (45%) were in chronic AF; in 40 patients (63%) the AF was of more than one year duration. A successful procedure is defined as PMBV achieved without acute mitral valve replacement, and a mitral valve area after PMBV of > or =1.5 cm2. RESULTS: Patients in chronic AF were significantly older, had a larger left atrial diameter and higher NYHA functional class, compared with patients in sinus rhythm (SR). The success rates of PMBV were 80.5% and 77.6% in patients with SR and AF, respectively (p = NS). Mean follow up was 4.2+/-2.6 years (n = 127). At four years' follow up the event-free survival was 86.5% in patients with SR, and 78.5% in those with chronic AF at baseline (p = 0.031). Multivariate analysis of the entire study population showed the presence of chronic AF to be the only pre-procedural independent predictor for severe mitral regurgitation after PMBV (p = 0.030), as well for an event (p = 0.039) and restenosis (p = 0.034) during follow up. The risk for an event or restenosis during follow up increased seven-fold when chronic AF at baseline was present for more than one year (p = 0.010). CONCLUSION: Pre-procedural chronic AF is an independent predictor for unfavorable outcome at short- and long-term follow up after PMBV. A longer duration of AF further increases the risk of an event or restenosis.     

Mitral balloon valvotomy for patients with mitral stenosis in atrial fibrillation: immediate and long-term results.

OBJECTIVES: The purpose of this study was to examine the effect of atrial fibrillation (AF) on the immediate and long-term outcome of patients undergoing percutaneous mitral balloon valvuloplasty (PMV). BACKGROUND: There is controversy as to whether the presence of AF has a direct negative effect on the outcome after PMV. METHODS: The immediate procedural and the long-term clinical outcome after PMV of 355 patients with AF were prospectively collected and compared with those of 379 patients in normal sinus rhythm (NSR). RESULTS: Patients with AF were older (62 +/- 12 vs. 48 +/- 14 years; p < 0.0001) and presented more frequently with New York Heart Association (NYHA) class IV (18.3% vs. 7.9%; p < 0.0001), echocardiographic score >8 (40.1% vs. 25.1%; p < 0.0001), calcified valves under fluoroscopy (32.4% vs. 18.8%, p < 0.0001) and with history of previous surgical commissurotomy (21.7% vs. 16.4%; p = 0.0002). In patients with AF, PMV resulted in inferior immediate and long-term outcomes, as reflected in a smaller post-PMV mitral valve area (1.7 +/- 0.7 vs. 2 +/- 0.7 cm2; p < 0.0001) and a lower event free survival (freedom of death, redo-PMV and mitral valve surgery) at a mean follow-up time of 60 months (32% vs. 61%; p < 0.0001). In the group of patients in AF, severe post-PMV mitral regurgitation (> or =3+) (p = 0.0001), echocardiographic score >8 (p = 0.004) and pre-PMV NYHA class IV (p = 0.046) were identified as independent predictors of combined events at follow-up. CONCLUSIONS: Patients with AF have a worse immediate and long-term outcomes after PMV. However, the presence of AF by itself does not unfavorably influence the outcome, but is a marker for clinical and morphologic features associated with inferior results after PMV.     

Combined atrial fibrillation ablation with mitral valve surgery

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate the efficacy and outcome of radiofrequency (RF) atrial fibrillation (AF) ablation in patients undergoing mitral valve (MV) surgery. METHODS: Between March 2002 and December 2004, 61 patients (mean age 65.4 +/- 10 years) underwent isolated endo-left atrial AF ablation using a unipolar RF device (Cardioblate; Medtronic, USA) in conjunction with 34 MV repairs and 27 MV replacements. AF was paroxysmal in 13 patients (21%), and permanent in 48 (79%), with a mean duration of 3.6 +/- 3.5 years. The etiology was degenerative in 35 patients (57%), rheumatic in 17 (28%), and ischemic in nine (17%). All patients received amiodarone postoperatively. RESULTS: No patients died during the study, and there were no thromboembolic complications. All patients had intraoperative conversion. Forty-one patients (67%) presented with postoperative relapse; definitive conversion was achieved in 34 (83%) cases within three months. The overall success rate was 75.4% at 14 +/- 8.8 months; success was greater in the MV repair group (85%) than in the MV replacement group (66.7%), though not significantly so (p = 0.09). Factors associated with definitive conversion included smaller left atrial size (p = 0.007), decreased left ventricular end-diastolic diameter (p = 0.04), and NYHA class I (p = 0.05). Age, AF duration and etiology were not associated with conversion, but associated coronary artery bypass grafting showed a strong trend towards significance (p = 0.07). In these patients, AF duration did not predict conversion to sinus rhythm. CONCLUSION: Combined AF ablation with MV surgery is safe and effective. Although AF ablation seems more beneficial with MV repair, the success rate may vary significantly according to patient characteristics.     

Efficacy of intra-operative radiofrequency ablation in patients with permanent atrial fibrillation undergoing concomitant mitral valve replacement

BACKGROUND: Permanent atrial fibrillation (AF) is present before operation and persists after surgery in 30-40% of patients undergoing mitral valve surgery. Using the maze procedure, 75-82% of patients can be cured of AF, but the procedure is difficult and long lasting. Percutaneous radiofrequency (RF) ablation has emerged as an effective therapy for AF in recent years. AIM: To assess the efficacy of intra-operative RF ablation of AF in patients undergoing mitral valve surgery. METHODS: 100 adults with permanent AF underwent mitral valve replacement. Patients were divided into two groups: the RF group--50 patients qualified for mitral valve replacement and RF ablation; and the control group--50 patients selected for mitral valve replacement without ablation. Odds ratio and 95% confidence interval were examined to assess the influence of several factors on the outcome (free from AF during one-year follow-up based on symptoms and serial Holter ECG recordings). RESULTS: Baseline clinical, demographic and echocardiographic characteristics were similar in both groups. Electrical cardioversion following surgery was required in 76% of patients from the RF group compared with 94% from the control group (p<0.002). In those who underwent cardioversion, sinus rhythm was restored more frequently in RF than control patients (32 vs. 16%, p<0.002). Sinus rhythm at hospital discharge was present in 56% of RF patients compared with 22% of controls (p=0.0001), and after one-year follow-up in 54 vs. 16% (p<0.001), respectively. The use of amiodarone was significantly lower in RF patients compared with controls (32 vs. 70%, p<0.05). NYHA class III (OR 8.5, CI 1.0-394) or IV (OR 36, CI 1.2-1958) and left atrial diameter >6 cm (OR 9.3, CI 0.5-5230) were identified as predictors of AF. CONCLUSIONS: Intra-operative RF ablation performed in the left atrium in patients with chronic AF undergoing mitral valve replacement significantly improves sinus rhythm restoration rate. Advanced heart failure (NYHA class IV) and left atrial diameter >6 cm are negative prognostic factors for sinus rhythm maintenance.     

Effect of maze procedure in patients with atrial fibrillation undergoing valve replacement

BACKGROUND AND AIMS OF THE STUDY: The study aim was to elucidate the impact of the maze procedure on late outcome after valve replacement. METHODS: Between 1992 and 2000, 241 patients underwent the maze procedure combined with valve replacement. Patients were allocated to three groups: aortic valve replacement (AVR/maze, n = 16); mitral valve replacement (MVR/maze, n = 148); and combined aortic and mitral valve replacement (DVR/maze, n = 77). RESULTS: Mean follow up was 3.9 +/- 2.3 years. Hospital mortality was 0% in the AVR/maze group, 2.0% (n = 3) in the MVR/maze group, and 3.9% (n = 3) in the DVR/maze group. Elimination of atrial fibrillation (AF) at discharge was achieved in 74.3-75.9% of cases. Freedom from recurrence of AF/atrial flutter was 71.2% in the AVR/maze group, 68.2% in the MVR/maze group, and 64.0% in the DVR/maze group at five-year follow up. By multivariate analysis, risk factors for recurrence of AF/atrial flutter included preoperative enlarged left atrial dimension >70 mm, decreased postoperative fractional shortening <30%, and absence of postoperative left atrial contraction. Freedom from stroke was 93.6% in patients who achieved regular rhythm (normal sinus rhythm or junctional rhythm), and 80.9% in those with recurrence of AF at five years after surgery (p = 0.03). CONCLUSION: The combined maze procedure and valve replacement is safe and effective in selected patients. Restoration of regular rhythm significantly reduced the incidence of late stroke.     

Clinical, echocardiographic, and hemodynamic characteristics of rheumatic mitral valve stenosis and atrial fibrillation

Chronic atrial fibrillation (AF) is associated with an increased frequency of embolic events and negative impact on cardiac function, and therefore, an increased morbidity and mortality risk in patients with rheumatic mitral valve stenosis (RMS). In the present study, the clinical, 2-D and Doppler echocardiographic, and left-and right-heart hemodynamic data were evaluated for 92 patients (68 women) with RMS and AF and compared with data from 118 patients (88 women) with RMS with sinus rhythm. The clinical, echocardiographic, and hemodynamic evaluations were performed within 1 to 7 days of each other. Patients with AF were older (45.7+/-13.4 vs 38.6+/-12.0 years, p < 0.01) and had a longer symptomatic period (108.2+/-117.9 vs 50.6+/-53.1 months, p < 0.01) compared with those with sinus rhythm. Most of the patients with AF were in NYHA functional capacity 3-4 (74% vs 19%), whereas most of the patients with sinus rhythm were in NYHA functional capacity 2. Patients with AF had a higher mitral valve score based on morphologic features ranging from 4 to 16 depending on the severity of disease (8.3+/-2.1 vs 6.5+/-1.9, p < 0.01) and greater left ventricular end-diastolic diameter (LVEDD) (52.3+/-8.7 vs 47.7+/-8.7 mm, p < 0.02), and end-systolic diameter (LVESD) (34.4+/-7.5 vs 30.9+/-7.5 mm, p < 0.01). Organic tricuspid valve involvement was diagnosed more frequently in patients with AF (61% vs 32%, p < 0.01). Mild mitral regurgitation was also more frequent in patients with AF (71%vs 51%, p < 0.03). The mitral valve area was similar in patients with and without AF (1.30+/-0.39 vs 1.39+/-0.41 cm2, p > 0.05). Mean diastolic mitral valve gradient and pulmonary artery pressure did not differ in patients with and without AF. Right atrial pressures were higher in patients with AF (7.6+/-3.3 vs 6.3+/-1.9 mm Hg, p < 0.02). The authors suggest that (1) AF occurred in older patients, who had a longer disease process and more serious symptoms; (2) hemodynamic derangements (mitral valve gradient, pulmonary artery pressure) did not differ in patients with and without AF; (3) greater mitral valve score, more tricuspid valve involvement, higher LVEDD, which are suggestive of greater rheumatic activity process were more frequently seen in patients with AF than in those without AF. These findings support the opinion that AF is a marker of widespread rheumatic damage in patients with RMS.     

Clinical determinants of sinus conversion by radiofrequency maze procedure for persistent atrial fibrillation in patients undergoing concomitant mitral valvular surgery

The radiofrequency Maze procedure can effectively restore sinus rhythm in most patients with atrial fibrillation (AF) and mitral valve disease. AF after cardiac surgery is associated with increased morbidity and mortality. However, clinical determinants of long-term postoperative AF after the radiofrequency Maze procedure and concomitant mitral valve surgery are poorly defined. This study comprised 99 consecutive patients with persistent AF and mitral valve disease who underwent radiofrequency Maze procedures and concomitant mitral valvular operations. The predictive values of clinical variables for postoperative AF were examined. After a mean follow-up period of 46.1+/-24.6 months, 83 patients (83.8%) had sinus conversion after the Maze procedure, and 16 patients remained in persistent or paroxysmal AF. Multiple logistic regression analysis determined that predictors of sinus conversion were preoperative left atrial diameter (odds ratio [OR] 1.127 per 1-mm increment in left atrial diameter, 95% confidence interval [CI] 1.045 to 1.215, p<0.002) and the duration of AF (OR 1.022 per 1-month increment in duration of AF, 95% CI 1.009 to 1.035, p<0.001). Discriminant analysis showed that the sinus conversion rate was significantly lower in patients with preoperative left atrial diameters>56.8 mm (p<0.001) or AF duration>66 months (p<0.001) than in patients with preoperative left atrial diameters<56.8 mm or AF duration<66 months. In conclusion, the preoperative left atrial size and duration of AF are primary predictors of sinus conversion by the radiofrequency Maze procedure for patients with persistent AF and mitral valve disease.     

Comparison of findings in patients with versus without atrial fibrillation just before isolated mitral valve replacement for rheumatic mitral stenosis (with or without associated mitral regurgitation)

Among 104 patients with mitral stenosis (MS) severe enough or symptomatic enough to warrant mitral valve replacement (MVR), 47 (45%) had atrial fibrillation (AF) and 57 (55%) had sinus rhythm just before the MVR. Of the latter 57 patients, 21 (37%) had had previous episodes compatible with AF. If these 21 patients were included with the 47 patients with electrocardiographic documentation of AF just before MVR, a total of 68 (65%) would have had > or =1 presumed episodes of AF before MVR. The 13 patients with previous mitral commissurotomy had a frequency of AF similar to that of the 91 whose first operation was MVR. Compared with the patients with sinus rhythm just before MVR, those with AF had more heart failure (functional class III or IV preoperatively, 79% vs 62%), larger left atria (6.0 vs 5.2 cm), larger left ventricles in peak systole (4.0 vs 2.6 cm), and more had 2 or 3 coronary arteries narrowed >50% in diameter (23% vs 10%).     

Effects of late regain of sinus rhythm on pulmonary artery pressure and functional status in patients with mitral valve replacement surgery and atrial fibrillation

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate the effects of regaining sinus rhythm (SR) on pulmonary artery pressure (PAP) and NYHA class in patients undergoing mitral valve replacement (MVR) surgery and in atrial fibrillation (AF). METHODS: Forty patients (mean age 50.7+/-8.2 years) with previous MVRS and chronic AF were included in the study; the mean postoperative interval was 54.7+/-31.8 months. Among these 40 patients, 22 (the study group) were treated with amiodarone (600 mg/day) and direct current (DC) cardioversion (CV), while 18 (control group) underwent normal treatment. RESULTS: In the study group, two patients regained SR with amiodarone loading, while 20 proceeded with DC CV at 21 days after amiodarone loading. SR was regained in 20 patients. The amiodarone dosage was lowered to 200 mg/day in the sixth postoperative week. Patients were followed for a mean of 18.0+/-4.4 months (range: 12-22 months). In the study group, recurrence of AF occurred in only one patient, at four months after DC CV. SR was maintained in 19 patients. At a clinical control examination, the mean NYHA class of study patients was decreased from 2.6+/-0.5 to 1.8+/-0.6 in two months, and to 1.5+/-0.6 in 12 months (p <0.01). Doppler echocardiographic follow up in the study group showed PAP to be significantly reduced, from 44.2+/-12.3 mmHg to 32.8+/-8.1 mmHg (p <0.01). CONCLUSION: In patients with MVR and AF, amiodarone treatment and DC CV achieved good early and mid-term success in regaining and maintaining SR. Regulation of rhythm was concomitant with a reduction in PAP and improved NYHA functional class. Hence, a special effort should be made to correct arrhythmia in patients with MVR and AF.     

Left atrial function as a predictor of haemodynamic response in patients with mitral stenosis: a dobutamine stress echocardiographic study

OBJECTIVE: The mechanisms of the different haemodynamic and clinical responses to dobutamine infusion in mitral stenosis (MS) are not clearly established. The aim of this study was to evaluate the relation between left atrial (LA) function and haemodynamic response in patients with MS during dobutamine infusion. METHODS AND RESULTS: Forty-two consecutive moderately symptomatic patients (33 women, 9 men; mean age 46+/-9, range from 26 to 66), New York Heart Association (NYHA) class II with MS (mean mitral valve area 1.7+/-0.1 cm2) were evaluated with dobutamine stress echocardiography. Haemodynamic measurements were obtained at rest and during peak dobutamine infusion. LA fractional shortening at rest was used as an index of global LA function. Group I consisting of patients with significantly elevated pulmonary artery pressure (> 60 mm Hg) and mean transmitral gradient (> 15 mm Hg) at peak dobutamine infusion were defined as haemodynamically serious MS. Group II consisted of the remaining 30 patients whose haemodynamic data were below these levels. While baseline haemodynamic parameters and mitral valve characteristics were not different between the two groups, LA fractional shortening was significantly lower (18.9+/-2.8 vs. 32.3+/-5.1%, p<0.0001) and left atrial dimension was significantly larger in group I (49.7+/-2.3 mm vs 43.6+/-5.3 mm, p<0.0001). Left atrial fractional shortening was negatively correlated with the increase in mean transmitral gradient (r:-0.58, p<0.01). When the patients were divided using a LA fractional shortening level of 25% as the cut-off point, we observed that the patients with low LA fractional shortening had a greater increase in mean transmitral gradient (7.3+/-3.1 mm Hg vs. 4.6+/-1.4 mm Hg), p = 0.005) and pulmonary artery pressure (22.4+/-3.5 mm Hg vs. 16.1+/-8.5 mm Hg, p = 0.001) compared to the patients with high LA fractional shortening. Based on these haemodynamic results, management was changed in 12 patients (28%): 5 underwent percutaneous mitral balloon commissurotomy and 7 received intensive medical treatment. CONCLUSIONS: The present study demonstrates that haemodynamic response during dobutamine stress echocardiography correlates with LA fractional shortening in patients with MS. The evaluation of left atrial function at rest in patients with ambiguous symptoms and mild mitral stenosis may be useful in clinical decision making. Atrial dysfunction at rest may predict the haemodynamic response during stress echo in these patients.     

Left atrial function, cytokines and soluble apoptotic markers in mitral stenosis: effects of valvular replacement

BACKGROUND: Patients with mitral stenosis (MS) and heart failure (HF) are characterized by changes in the left atrial (LA) function and activation of the apoptotic process. The purpose of the present study was the evaluation of the effect of mitral valve replacement on the LA function, on inflammatory process and apoptotic markers in patients with MS and HF. METHODS: We studied 30 patients with MS and HF (15 in NYHA III-IV and 15 in NYHA IV) in sinus rhythm (mean age 56.2 +/- 4.6 years), and 20 age and gender matched healthy volunteers. Blood samples were obtained before and 6 months after surgical mitral valve replacement, and plasma levels of soluble Fas/APO-1 receptor (sFas), tumor necrosis factor-alpha (TNF-a) and interleukin-6 (IL-6) were measured. Echocardiographically, LA volumes were measured at mitral valve opening (Vmax), at the onset of left atrial systole (P wave of the electrocardiogram, Vp) and at the mitral valve closure (Vmin). LA contractile function was assessed by the LA active emptying fraction (ACTEF). RESULTS: After mitral valve replacement, TNF-a, IL-6 and sFas levels, as well as the Vmax LA volume, were significantly reduced (p < 0.05). ACTEF showed a significant postoperative decrease (0.29 +/- 0.09 vs. 0.23 +/- 0.06, p < 0.01) and it was significantly correlated with sFas (r = -0.88, p = 0.001), TNF-a (r = -0.81, p = 0.001) and IL-6 (r = -0.74, p = 0.001) levels. CONCLUSION: The present findings indicate that mitral valve replacement in patients with mitral valve stenosis, reduces the size of the left atrium, improves left atrial contractile function and depresses inflammatory and apoptotic process.     

Impaired fibrinolytic capacity in rheumatic mitral stenosis with or without atrial fibrillation and nonrheumatic atrial fibrillation

Chronic atrial fibrillation (AF) has often been associated with systemic embolization, and patients with mitral stenosis (MS) have the highest thromboembolic risk. Increased risk of thromboembolism could be in part due to impaired fibrinolytic function. Global fibrinolytic capacity (GFC) is an innovative technique for evaluating the entire fibrinolytic system.The aim of our study was to evaluate fibrinolytic activity in patients with rheumatic and nonrheumatic chronic AE To investigate fibrinolytic activity, we assessed GFC in peripheral blood samples of 32 patients with nonrheumatic AF (14 women; mean age, 56 +/- 1 years), 30 patients with rheumatic MS and AF (23 women; mean age, 35 +/- 9 years), and 32 patients with rheumatic MS and sinus rhythm (24 women; mean age, 36 +/- 8 years). The control group comprised 30 healthy adult subjects in normal sinus rhythm. Patients with chronic AF (rheumatic and nonrheumatic) had lower GFC than did the controls (P = .0001). The rheumatic AF group also showed decreased levels of GFC compared with the nonrheumatic AF group, with the rheumatic MS and sinus rhythm group, and with controls (P = .03, P = .02, P = .0001, respectively). GFC was lower in patients with rheumatic MS and sinus rhythm than in controls (P = .003). Although there were correlations between GFC and mitral valve area, transmitral mean gradient, left atrial diameter, and mitral calcification in patients with rheumatic MS, multivariate analysis showed only transmitral gradient as an independent factor affecting GFC. Patients with AF have decreased GFC, a finding that suggests the presence of a hypofibrinolytic state. Fibrinolytic dysfunction was more pronounced in rheumatic MS patients with AF than in those with nonrheumatic AF. Moreover, patients with rheumatic MS and sinus rhythm had decreased global fibrinolytic activity. Hypofibrinolysis documented by decreased GFC can be one of the important causes of increased risk of embolism in patients with AF and rheumatic MS.     

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

AIMS: To examine the impact of pre-operative atrial fibrillation (AF) on the outcome of mitral valve repair (MVR) for degenerative mitral regurgitation (MR). METHODS AND RESULTS: 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. CONCLUSION: 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.     

Increased inflammatory cell infiltration in the atrial myocardium of patients with atrial fibrillation

Atrial fibrillation (AF) may be caused by structural and electrophysiological changes in the atria induced by inflammation. This study analyzed 35 adult patients with symptomatic severe mitral valve disease and moderate-to-severe tricuspid valve disease and without coronary artery disease who underwent valve operations for congestive heart failure; 18 patients had persistent AF and 17 patients had no history or electrocardiogram examination of AF before surgery. Atrial appendageal tissues obtained during surgery were evaluated for histopathological changes. The number of inflammatory cells identified as CD45-positive cells in the right atrial myocardium in the AF group (7.5 +/- 7.5 cells per high power field) was significantly higher than that of normal controls (2.7 +/- 1.5 cells per high power field, p = 0.0018). The number of inflammatory cells in the right atrial myocardium did not differ between the sinus group and normal controls (2.7 +/- 1.5 vs 2.6 +/- 2.2 cells per high power field, p >0.05). Additionally, the number of inflammatory cells in the atrial myocardium did not differ between the right and left atria in patients with AF (7.5 +/- 7.5 cells per high power field for right atria vs 7.1 +/- 4.2 cells per high power field for left atria, p = 0.7563). Moreover, correlation analysis revealed a significant association between the number of inflammatory cells in the right atrial myocardium and the number of inflammatory cells in the left atrial myocardium in patients with AF (r = 0.6145, p = 0.0067). In conclusion, inflammatory cell infiltration increases in the atrial myocardium of patients with AF.     

Balloon mitral commissurotomy for patients with mitral stenosis in atrial fibrillation: ten-year clinical and echocardiographic actuarial results

BACKGROUND AND AIM OF THE STUDY: Controversy persists as to whether atrial fibrillation (AF) has a direct negative effect on the outcome of percutaneous balloon mitral commissurotomy (PBMC). The study aim was to assess the effect of AF on immediate and 10-year clinical and echocardiographic actuarial results of patients with rheumatic mitral stenosis undergoing PBMC. METHODS: A total of 195 consecutive patients with AF (group 1) was analyzed and compared with 195 patients in sinus rhythm (group 2), matched for the severity of mitral valve morphological changes. RESULTS: Group 1 patients were older (43.8 + 12 versus 30.5 +/- 12.7 years; p <0.001), and a greater proportion had grade 1 mitral regurgitation (25.1 versus 9.7%; p <0.0001). The procedural success was 89.8% in group 1 and 92.3% in group 2 (p = NS), but group 1 patients had a smaller mitral valve area (2.1 +/- 0.4 versus 2.3 +/- 0.4 cm2; p <0.0001). Patients in AF had a lower 10-year survival (91.4 versus 99.4%; p = 0.018), a lower 10-year event-free-survival (60.3 versus 70%; p = 0.02), and a lower 10-year freedom from restenosis (40 versus 66%; p = 0.048). AF was an independent predictor of overall mortality (OR = 10.79; p <0.033) and of combined events (death, redo PBMC or mitral valve surgery; OR = 1.95; p <0.012), and was a univariate predictor of restenosis (p = 0.048). CONCLUSION: Patients with AF have good immediate results, but poorer long-term outcome after PBMC. AF a marker of worse prognosis in patients with mitral stenosis as it is in the general population.     

Preoperative atrial size predicts the success of radiofrequency maze procedure for permanent atrial fibrillation in patients undergoing concomitant valvular surgery

BACKGROUND: The radiofrequency (RF) maze procedure can effectively restore sinus rhythm and atrial transport function in the majority of patients with permanent atrial fibrillation (AF) and mitral valve disease. No previous study has described a cutoff value of preoperative atrial size determined by the discriminant analysis in predicting the success of sinus conversion by the RF maze procedure for permanent AF in patients with mitral valve disease. METHODS AND RESULTS: This study included 81 patients with permanent AF and mitral valve disease who underwent the RF maze IV procedure while undergoing concomitant valvular operations. There was one surgical death (1.2%). Another patient died of acute necrotizing pancreatitis 13 months later. Two patients (2.5%) developed sick sinus syndrome and received transvenous permanent pacemaker implantation. In the remaining 77 patients, there were 38 men and 39 women, with a mean (+/- SD) age of 51 +/- 11 years. At a mean follow-up time of 38 months, 65 patients (84.4%) had persistent sinus conversion that had been accomplished by the RF maze procedure (group 1), and 12 patients (15.6%) did not regain sinus rhythm (group 2). We evaluated the preoperative variables between the two groups. Univariate analysis demonstrated that the preoperative left atrial area and the left atrial diameter of group 1 patients were significantly smaller than those of group 2 patients. Group 1 had significantly fewer patients associated with tricuspid valve disease than did group 2. By multiple stepwise logistic regression analysis, only the preoperative left atrial area was an independent determinant of sinus conversion by the RF maze procedure (odds ratio, 0.961; 95% confidence interval, 0.935 to 0.988; p < 0.005). Linear discriminant analysis demonstrated that the sensitivity and specificity of the cutoff value of 56.25 cm(2) of the preoperative left atrial area in predicting the sinus conversion by the RF maze procedure were 50.0% and 86.2%, respectively, and the positive and negative predictive values were 40.0% and 90.3%, respectively. CONCLUSION: The preoperative left atrial area is an independent determinant of sinus conversion by the RF maze procedure for patients with permanent AF and mitral valve disease.     

The long-term effect of successful mitral balloon valvotomy on left atrial size.

BACKGROUND AND AIM OF THE STUDY: The study aim was to determine the extent of regression of left atrial (LA) enlargement following mitral balloon valvotomy (MBV) for mitral stenosis. METHODS: Data obtained from 205 patients before, and at a mean of 31.0 +/- 21.1 months (range: 6 to 86.3 months) after successful MBV were analyzed retrospectively. RESULTS: The invasively determined mitral valve area increased from 0.81 +/- 0.27 cm2 at baseline to 1.73 +/- 0.54 cm2 immediately after valvotomy (p <0.0001), and the mean mitral gradient fell from 15.6 +/- 5.3 to 5.4 +/- 2.5 mmHg (p <0.0001). Similar changes were noted in Doppler-determined mitral valve area (0.89 +/- 0.16 to 1.97 +/- 0.29 cm2; p <0.0001) and gradient (12.6 +/- 5.3 to 4.9 +/- 1.7 mmHg; p <0.0001). In comparison with baseline, significant (p <0.0001) reductions were noted at follow up in the echocardiographic anteroposterior (48.7 +/- 6.9 to 42.4 +/- 6.6 mm), superior-inferior (68.5 +/-8.1 to 59.6 +/- 8.2 mm) and medial-lateral LA dimension (51.2 +/- 6.7 to 44.1 +/- 7.7 mm) and calculated LA volume (91.6 +/- 29.1 to 60.7 +/- 23.8 cm3) Patients in atrial fibrillation had larger LA dimensions, but substantially smaller absolute and relative reduction in LA size at follow up than patients in sinus rhythm. Among patients with prevalvotomy LA enlargement, normalization of LA dimension at follow up was seen in 29.2% of patients in sinus rhythm, but in none of the 32 with atrial fibrillation. CONCLUSIONS: Successful MBV results in significant long-term reduction in LA size in most patients, but normalization of LA size is unusual.