Left atrial volume: predictor of atrial fibrillation in patients with degenerative mitral regurgitation

BACKGROUND AND AIM OF THE STUDY: In patients with mitral regurgitation (MR) due to degenerative mitral valve prolapse (MVP), preoperative atrial fibrillation (AF) has been identified as an independent predictor of survival after surgery for MR. Thus, the determinants of preoperative AF may have critical implications to evaluate the timing of mitral valve repair. The study aim was to investigate the role of left atrial (LA) volume in predicting preoperative AF in patients with severe MR due to degenerative MVP. METHODS: Sixty-six patients with severe degenerative MR (regurgitant volume > or =60 ml, regurgitant fraction > or =50%, effective regurgitant orifice area > or =0.4 cm(2)) in sinus rhythm (SR) at diagnosis and conservatively managed were eligible for the study. Complete two-dimensional (2-D) echocardiographic and Doppler measurements, including the measurement of maximum LA volume, were performed in all patients. RESULTS: During follow up under conservative management (18.1+/-4.8 months), eight patients (12%) experienced conversion to AF, and 58 remained in SR. The mean LA dimension was 4.0+/-0.5 cm in patients with SR, and 5.1+/-0.8 cm in those who developed AF (p <0.0001). The mean LA volume and LA volume index (indexed to body surface area) were 95 +/-23 ml and 60+/-14 ml/m(2) respectively in patients with SR, and 166+/-66 ml and 104+/-42 ml/m(2) respectively in those who developed AF (both p <0.0001). The optimal cut-off value for LA volume to predict AF conversion was 117.5 ml (sensitivity 88%, specificity 83%), and for LA volume index was 75 ml/m(2) (sensitivity 88%, specificity 88%). CONCLUSION: LA volume measurement should be considered in patients with degenerative severe MR diagnosed in SR. A LA volume index > or =75 ml/m(2) reflects the risk of subsequent AF, and patients should be closely monitored.     

Mitral valve repair versus replacement for isolated non-ischemic mitral regurgitation in patients with preoperative left ventricular dysfunction. A long-term follow-up echocardiography study.

The aim of this study was to evaluate LV function, by means of echocardiography, after mitral valve repair (MVr) or mitral valve replacement (MVR) in patients (pts) with chronic degenerative mitral regurgitation (MR) and depressed LV systolic function during a 6-years follow-up (FU) period. PATIENTS AND METHODS: Forty-five pts with moderately severe or severe MR and preoperative EF相似文献   

Echocardiographic prediction of left ventricular dysfunction after mitral valve repair for mitral regurgitation as an indicator to decide the optimal timing of repair

OBJECTIVES: This study sought to determine whether echocardiography before mitral valve repair (MVR) for mitral regurgitation (MR) was predictive of postoperative left ventricular (LV) dysfunction and useful for deciding the optimal timing of repair. BACKGROUND: Some reports have shown that the preoperative echocardiographic data of left ventricular ejection fraction (LVEF) and left ventricular end-systolic diameter (LVDs) were good predictors of postoperative LV dysfunction. However, few reports were based on long-term follow-up data of large numbers of patients who underwent MVR in the last decade. METHODS: A total of 274 patients with moderate or severe MR underwent MVR between October 1, 1991, and September 30, 2000. Among them, 171 patients who had both an operation for isolated MR due to degenerative pathology and a postoperative echocardiogram were studied. Postoperative echocardiograms were performed 3.9 +/- 2.4 years after the operation.The LVEF decreased from 66 +/- 10% before surgery to 63 +/- 11% after surgery (p < 0.0001). On univariate analysis, preoperative LVEF and LVDs correlated with postoperative LVEF (r = 0.41 and r = -0.39, respectively). Overall, postoperative LV dysfunction (defined as LVEF <50%) was not frequent (12%). However, the incidence of postoperative LV dysfunction was high in patients with preoperative LVEF <55% (38%) or LVDs > or =40 mm (23%). CONCLUSIONS: In patients with MR, the echocardiographic data of LVEF and LVDs were good predictors of postoperative LV dysfunction. When a decrease in LVEF or an increase in LVDs is detected, MVR should be considered to preserve postoperative LV function.     

Long-term outcomes after mitral ring annuloplasty for degenerative mitral regurgitation: Duran ring versus Carpentier-Edwards ring

BACKGROUND AND AIM OF THE STUDY: The preferred choice of annuloplasty ring in mitral surgery has not yet been determined. The study aim was to compare the effects of using two ring types, the Duran and the Carpentier-Edwards, for degenerative mitral valve repair. METHODS: The follow up data were reviewed from 294 patients who underwent mitral valvuloplasty for degenerative mitral regurgitation (MR) with either a Carpentier-Edwards ring (n = 153) or a Duran ring (n = 141), between 1994 and 2004. The long-term clinical and echocardiographic outcomes were compared. RESULTS: There were no inter-group preoperative demographic differences. The preoperative left ventricular (LV) ejection fraction (EF) and MR grade were similar in both groups, but the left atrial (LA) size, LV mass and LV dimension were significantly greater in the CE group. Rates of overall survival, reoperation-free survival and MR (> or = 3)-free survival were similar in the two groups (five-year MR-free survival 75.1 +/- 4.6% for CE and 82.4 +/- 4.5% for Duran; p = 0.83). The CE group showed an overall superior five-year mitral stenosis (MS)-free survival. Significantly more Duran patients had a mean transmitral pressure gradient (MPG) of > or = 10 mmHg (five-year MS (MPG > or = 10 mmHg)-free survival rate: 91.2 +/- 2.8% in for CE and 65.1 +/- 10.7% for Duran group; p = 0.011). The LV EF did not change over time in either group. In contrast, the LV mass and LV dimension decreased significantly after surgery in both groups, but no significant inter-group difference was seen for either index. CONCLUSION: Although the Duran and Carpentier-Edwards rings showed comparable long-term outcomes in terms of LV function, MR recurrence, survival and reoperation, a greater tendency towards MS development was observed with the Duran ring, this being most likely due to late pannus formation.     

Atrial fibrillation complicating the course of degenerative mitral regurgitation: determinants and long-term outcome

OBJECTIVES: The study was done to define the incidence, determinants and prognostic implications of onset of atrial fibrillation (AF) during follow-up of mitral regurgitation (MR) initially in sinus rhythm. BACKGROUND: The rates and clinical implications of AF in MR are undefined. METHODS: We analyzed the occurrence of AF under conservative management in two populations of patients with degenerative MR in sinus rhythm at diagnosis: 1) 360 patients (65 +/- 13 years, 74% men) with MR due to flail leaflets; and 2) 89 residents of Olmsted County, Minnesota (67 +/- 17 years, 56% men) with grade 3 or 4 MR due to simple mitral valve prolapse (MVP) diagnosed echocardiographically. RESULTS: In patients with MR due to flail leaflets, AF rates at 5 and 10 years were 18 +/- 3% and 48 +/- 6%, respectively, and the linearized rate was 5.0 +/- 0.7% per year. Development of AF during follow-up was independently associated with high risk of cardiac death or heart failure (adjusted risk ratio 2.23, p = 0.025). The AF rate at 10 years was higher in patients >or=65 years (75 +/- 10% vs. 24 +/- 6%, p < 0.0001) and in those with baseline left atrial (LA) dimension >or=50 mm (67 +/- 8% vs. 37 +/- 9%, p < 0.001). In multivariate analysis, independent baseline predictors of AF were age and LA diameter (both p < 0.01). In patients with MR due to MVP, similar rates of AF (41 +/- 7% vs. 44 +/- 6% at nine years, p > 0.50) and predictors of AF (age and LA dimension, both p < 0.006) were noted. CONCLUSIONS: In patients with degenerative MR in sinus rhythm at diagnosis, the incidence of AF occurring under conservative management is high and similar whether the cause of MR is flail leaflet or simple MVP. After onset of AF, an increased cardiac mortality and morbidity are both observed under conservative management. The risk of AF increases with advancing age and larger LA dimension. These data suggest that the clinical management of MR should take into account the high incidence, excess risk, and predictors of AF.     

Percutaneous mitral valve repair for mitral regurgitation

Mitral regurgitation (MR) associated with, ischemic, and degenerative (prolapse) disease, contributes to left ventricular (LV) dysfunction due to remodeling, and LV dilation, resulting in worsening of MR. Mitral valve (MV) surgical repair has provided improvement in survival, LV function and symptoms, especially when performed early. Surgical repair is complex, due to diverse etiologies and has significant complications. The Society for Thoracic Surgery database shows that operative mortality for a 1st repair is 2% and for re-do repair is 4 times that. Cardiopulmonary bypass and cardiac arrest are required. The attendant morbidity prolongs hospitalization and recovery. Alfieri simplified mitral repair using an edge-to-edge technique which subsequently has been shown to be effective for multiple etiologies of MR. The MV leaflers are typically brought together by a central suture producing a double orifice MV without stenosis. Umana reported that MR decreased from grade 3.6 +/- 0.5 to 0.8 +/- 0.4 (P < 0.0001) and LV ejection fraction increased from 33 +/- 13% to 45 +/- 11% (P = 0.0156). In 121 patients, Maisano reported freedom from re-operation of 95 +/- 4.8% with up to 6 year follow-up. Oz developed a MV "grasper" that is directly placed via a left ventriculotomy and coapts both leaflets which are then fastened by a graduated spiral screw. An in-vitro model using explanted human valves showed significant reduction in MR and in canine studies, animals followed by serial echo had persistent MV coaptation. At 12 weeks the device was endothelialized. These promising results have paved the way for a percutaneous or minimally invasive-off pump mitral repair. Evalve has developed catheter-based technology, which, by apposing the edges of a regurgitant MV, results in edge-to-edge repair. Release of the device is done after echo and fluoroscopic evaluation under normal loading conditions. If the desired effect is not produced the device can be repositioned or retrieved. Animal studies show excellent healing, with incorporation of the device into the leaflets at 6-10 weeks with persistent coaptation. Another percutaneous approach has been to utilize the proximity of the coronary sinus (CS) to the mitral annulus (MA). Placement of a self-compressing device in the CS along the region of the posterior MA has, in canine models, reduced MR and addresses the issues of MA dilation and its contribution to MR. Ongoing studies are underway for both techniques.     

Favorable effect of balloon mitral valvuloplasty on the incidence of atrial fibrillation in patients with severe mitral stenosis.

BACKGROUND: The long-term effect of balloon mitral valvuloplasty (BMV) on the incidence of atrial fibrillation (AF) in patients with severe mitral stenosis (MS) remains undetermined. AIMS: To assess the effect of successful BMV on the incidence of chronic AF in patients with severe MS, compare the results with historical controls, and identify factors associated with AF in such patients. METHODS: Retrospective analysis of 382 consecutive patients with severe MS and in sinus rhythm (SR) who underwent successful BMV (post procedure mitral valve area (MVA) > or =1.5 cm(2), mitral regurgitation (MR) < or =2/4) at our hospital and followed-up for 1-15.6 (mean 5.6 +/- 3.9) years with clinical and echocardiographic examination. RESULTS: Thirty-four (8.9%) patients developed AF at follow-up (group A) and 348 patients (group B) remained in SR. At baseline, and in comparison with group B, patients who developed AF (group A) were older, had higher mitral echo score but equal MVA and left atrial (LA) size. The postprocedure MVA was smaller in group A (1.7 +/- 0.3 cm(2)) than in group B (2.0 +/- 0.2 cm(2;) P = 0.002). At follow-up, and in comparison to group B, group A had smaller MVA (1.5 +/- 0.4 cm(2) vs 1.8 +/- 0.4 cm(2) P <0.0001), larger LA dimension (49.4 +/- 6.5 vs 42 +/- 6.5 mm; P <0.0001) and higher restenosis rate (35% vs 14%; P = 0.001). Multivariate logistic regression analysis identified age at follow-up (P < 0.0001), LA size at follow-up (P = 0.004), and MVA at follow-up (P = 0.006) as predictors of AF. CONCLUSIONS: This study demonstrated favorable effect of BMV on the incidence of AF (8.9%) in patients with severe MS in comparison with reported series (29%) of patients with severe MS with similar baseline characteristics who were not submitted to any intervention. The predictors of AF were age, larger LA, and smaller MVA, at follow-up.     

Surgical treatment of mitral regurgitation associated with enlarged left ventricle

BACKGROUND AND AIM OF THE STUDY: Few long-term results exist of mitral valve replacement (MVR) in patients with chronic mitral regurgitation (MR) and severely enlarged left ventricle. Hence, the present study was conducted to provide additional data in this respect. METHODS: Between April 1988 and September 2000, 45 patients (28 males, 17 females; mean age 33.8+/-10.5 years; range: 13-58 years) with a left ventricular (LV) diastolic diameter (LVDD) >70 mm underwent MVR at Anzhen Hospital. MR was rheumatic in origin in 36 patients (80%) and congenital in nine (20%). Thirteen patients were in NYHA class II, and 32 in classes III -IV. The cardiothoracic ratio was 0.64+/-0.12 (range: 0.47-0.84). The ECG showed LV hypertrophy to be present in all patients. Echocardiography showed severe MR and LV hypertrophy in all patients: LVDD was 76.3+/-4.1 mm (range: 70.2-89.6 mm). MVR was performed under hypothermic cardiopulmonary bypass. RESULTS: Two of 45 patients died perioperatively (mortality rate 4.4%). At two weeks after surgery, echocardiography showed a reduction in LVDD (from 76.3+/-6.5 to 65.0+/-5.2 mm) (p <0.01). Follow up was completed in 37 patients (82%). Mean follow up was 4.69 years (range: 1-12.33 years). Nine patients were in NYHA class I, 21 in class II, and five in class III. Late mortality was 5%. LVDD was further decreased at late control from 76.3+/-6.5 to 60.0+/-6.1 mm (p <0.001). CONCLUSION: MVR is indicated in patients with mitral insufficiency and highly dilated ventricles. In addition, perioperative mortality was acceptable and late results satisfactory. Moreover, the intervention has the potential to reduce severe LV dilation, and in some cases to revert ventricular size to normal.     

Preoperative predictors of late postoperative outcome among patients with nonischemic mitral regurgitation with 'high risk' descriptors and comparison with unoperated patients

Among patients with chronic nonischemic mitral regurgitation (MR), high short-term mortality risk can be identified by left (LV) and/or right ventricular (RV) ejection fraction (EF) criteria (LVEF 20%, MVR significantly improved survival versus medical treatment (rest: p < 0.0001, exercise: p = 0.0003). In high risk MR patients, MVR improves survival; preoperative RV performance can define subgroups with different long-term postoperative survival.     

Ischemic mitral valve regurgitation grade II-III: correction in patients with impaired left ventricular function undergoing simultaneous coronary revascularization.

BACKGROUND AND AIM OF THE STUDY: Mitral valve regurgitation (MVR), occurring as a result of myocardial ischemia and global left ventricular (LV) dysfunction, is predictive of poor outcome. The study aim was to assess the feasibility of mitral valve surgery concomitant with coronary artery bypass grafting (CABG) in patients with ischemic MVR grade II-III and impaired LV function. METHODS: Between January 1996 and July 2000, 99 patients with grade II and III ischemic MVR and LV ejection fraction (LVEF) 17-30% underwent either combined mitral valve surgery and CABG (group I, n = 49) or isolated CABG (group II, n = 50). LVEF (%), LV end-diastolic diameter (LVEDD; mm), LV end-diastolic pressure (LVEDP; mmHg), LV end-systolic diameter (LVESD; mm) respectively were 27.5+/-5, 67.7+/-7, 27.7+/-4 and 51.4+/-7 in group I versus 27.8+/-4, 67.5+/-6, 27.5+/-5 and 51.2+/-6 in group II. In group I, mitral valve repair was performed in 43 patients (88%) and replacement in six (12%). RESULTS: Preoperative data analysis showed no difference between groups. Five patients (10%) died in group I, compared with six (12%) in group II (p = NS). Within six months of surgery, LV function and geometry improved significantly in group I versus group II (LVEF, p <0.001; LVEDD, p = 0.002; LVESD, p = 0.003, LVEDP, p <0.001); only mild improvements were seen in group II. The regurgitation fraction decreased significantly in group I patients after surgery (p <0.001). Cardiac index increased significantly in groups I and II (p <0.001 and p = 0.03, respectively). In group I at follow up, four of six patients undergoing mitral valve replacement died, compared with five of 43 patients (11.5%) undergoing mitral valve repair (p = 0.007). At three years, the overall survival in group II was significantly lower than in group I (p <0.009). CONCLUSION: Both MV repair and replacement preserving subvalvular apparatus in patients with impaired LV function offered acceptable outcome in terms of morbidity and survival. Surgical correction of grade II-III MVR in patients with impaired LV function should be taken into consideration as it provides better survival and improves LV function.     

Early beneficial effect of preservation of papillo-annular continuity in mitral valve replacement on left ventricular function

BACKGROUND AND AIM OF THE STUDY: Impairment of left ventricular (LV) function after mitral valve replacement (MVR) has been the most important factor to determine morbidity and mortality. With this in mind, LV performance in the postoperative period was assessed with and without preservation of papillo-annular continuity in MVR. METHODS: Between March 1994 and August 1998, a total of 383 valve prostheses (202 MVR, 65 AVR, 58 MVR+AVR) were implanted in 325 patients, 177 of whom underwent MVR with Starr Edwards ball cage prostheses (the study group). Of these 177 patients, 105 had MVR with preservation of the posterior mitral leaflet (group I), and 72 had conventional MVR (group II). Predominant lesions were mitral stenosis in 81, mitral regurgitation in 42, and mixed mitral lesion (MS/MR) in 54. Concomitant tricuspid valve annuloplasty was performed in 13, and atrial septal defect repair in five. Sixteen patients underwent MVR for mitral restenosis. In-vivo performance of the prostheses and LV function was evaluated by M-mode and Doppler echocardiography. RESULTS: At 3-6 months clinical improvement was seen in NYHA class, with reduction in cardiothoracic ratio among patients with preserved papillo-annular continuity, irrespective of lesion type. Significant reductions (p <0.05) were seen in left atrial dimensions (54.10 +/- 8.79 preop. versus 44.64 +/- 8.54 postop.; p <0.05), left ventricular end-diastolic dimensions (LVEDD) (50.84 +/- 10.42 preop. versus 41.21 +/- 7.16 postop.; p <0.05) and end-systolic dimensions (LVESD) (34.76 +/- 7.94 preop. versus 28.81 +/- 5.79 postop.; p <0.05) in patients who had their posterior mitral leaflet preserved with significant improvement in ejection fraction (60.31 +/- 8.22 versus 64.47 +/- 7.93; p <0.05). Further analysis of data in group I patients showed significant reductions in left atrial dimensions, LVESD and peak gradient, along with improved ejection fraction compared with conventional (group II) patients. CONCLUSION: Deterioration in LV function in patients undergoing conventional MVR indicates chordal resection as a putative mechanism. This study supports the concept that maintenance of continuity between the mitral annulus and papillary muscles has a beneficial effect on postoperative LV function, and is particularly important in patients with mitral stenosis with depressed preoperative LV systolic function.     

Changes in systolic left ventricular function in isolated mitral regurgitation. A strain rate imaging study.

AIMS: The aim of the present study is to understand the changes in left ventricular (LV) regional systolic deformation based on strain rate (SR) imaging in patients with isolated mitral regurgitation (MR). Progressive LV dilatation and irreversible myocardial damage as a result of chronic isolated MR are important causes of morbidity and mortality in patients following valve surgery. To date, there is no specific diagnostic method to detect subclinical changes in systolic function before irreversible dysfunction occurs. METHODS AND RESULTS: Seventy-seven individuals were studied: 54 asymptomatic patients (age 56 +/- 12) with isolated non-ischaemic MR divided into three groups: mild, moderate, and severe and 23 healthy subjects. All underwent a standard echo examination and a tissue Doppler study. A mathematical study was carried out to predict how SR should alter with increasing dimensions and due to irreversible myocardial damage. Radial as well as longitudinal peak systolic SR was significantly decreased in patients with severe MR compared to the other groups (LV posterior wall: P = 0.0006, septum: P = 0.0004, LV lateral wall: P = 0.0003). From both modelling and in our patients, deformation correlated inversely with LV end-diastolic diameter and end-systolic diameter (ESD). Deformation measurements (corrected for increased geometry) enabled the identification of patients classically referred to as at risk of irreversible myocardial damage (ESD > or = 4.5 cm). CONCLUSION: In patients with a wide range of MR, deformation remains unchanged due to a balance of increased dimensions and increased stroke volume. Only when contractility is expected to change, deformation will significantly decrease. SR imaging indices, corrected for geometry, might potentially be useful in detecting subclinical deterioration in LV function in asymptomatic patients with severe MR.     

Diastolic unloading and improved LV pump efficiency early after repair of the insufficient mitral valve

BACKGROUND: This study aimed to evaluate the acute effect of mitral valve repair (MVR) on LV hemodynamics and geometry in patients with normal ventricular function. METHODS: In 10 patients with severe mitral regurgitation undergoing MVR, pressure-volume relationships were recorded before annuloplasty prior to and after hemodilution and after MVR during stable circulatory condition, using the conductance catheter technique (CC). Analyses were done off-line; volume calibration was based on data obtained after completion of valve repair (mean +/- s.d.). RESULTS: CC showed that only 61 +/- 15 % of left ventricular output was ejected into the systemic circulation, regurgitation volume being 39 +/- 15 %. MVR led to a reduction in LV stroke work index from 4.7 +/- 1.8 mm Hg x l x m (-2) at before valve repair to 2.2 +/- 1.0 mm Hg x l x m (-2) after surgery at unchanged cardiac index. LV diastolic filling parameters improved: LV relaxation time constant tau decreased from 52 +/- 15 to 37 +/- 11 ms and dP/dt (min) increased from - 873 +/- 231 to - 1286 +/- 283 mm Hg x s (-1). CONCLUSIONS: Despite cardioplegic arrest, MVR leads to acute improvement of diastolic LV function early after the operation. This may explain why valve repair has an acute positive effect in patients with impaired LV function.     

Impact of atrial fibrillation on clinical status, atrial size and hemodynamics in patients after mitral valve replacement.

BACKGROUND AND AIM OF THE STUDY: The association between mitral valve disease and atrial fibrillation (AF) is well known, but few data exist regarding the impact of AF after mitral valve replacement (MVR) on NYHA functional class, atrial size and hemodynamic parameters. The present study was conducted to evaluate these issues. METHODS: Eighty-six patients (26 men, 60 women) who underwent MVR were evaluated by transthoracic echocardiography. Fifty-nine patients had chronic AF (AF group), and 27 were in sinus rhythm (sinus group). Variables analyzed included end-systolic left atrial and right atrial areas, tricuspid regurgitation, and presence and duration of AF. Peak and mean transprosthetic mitral valve gradients and pulmonary pressure were estimated by Doppler echocardiography. RESULTS: Groups were matched for age, sex and time from MVR (mean 6.6 years). Sixty-four patients (77%) had rheumatic heart disease, 18 (21%) had mitral valve disease, and two (2%) had mitral valve prolapse. Mean duration of AF was 11+/-12 years (range: 8-50 years). Preoperatively, AF patients had a worse NYHA class than sinus patients (2.8+/-0.8 versus 1.1+/-0.7, p = 0.001), but both had similar fractional shortening of the left ventricle and preserved prosthetic mitral valve function. Multivariate analysis identified AF as a single predictor of NYHA class after MVR. Although left and right atrial areas were larger in AF patients (47+/-25 versus 27+/-7 cm2, p = 0.0001 and 30+/-12 versus 17+/-5 cm2, p = 0.0001, respectively), the left:right atrial size ratio was not significantly different between groups. Multivariate analysis identified mean transmitral gradient and duration of AF as independent predictors of left atrial size after MVR (p = 0.01 and p = 0.0001, respectively). Tricuspid regurgitation and duration of AF were independent predictors of right atrial size (p = 0.003 and p = 0.0001, respectively). CONCLUSION: The presence of AF after MVR is associated with a worse NYHA functional class, increased transmitral gradients, and larger areas of both atria, when compared with sinus rhythm. Hence, a special effort should be made to correct arrhythmia during surgery, and in case of paroxysmal arrhythmia, earlier surgery should be considered before the condition becomes chronic.     

Left ventricular geometry and operative mortality in patients undergoing mitral valve replacement.

BACKGROUND: Distortion of left ventricular (LV) shape is often associated with LV dysfunction and is thought to be an independent predictor of survival in patients with coronary disease. HYPOTHESIS: The purpose of this study was to examine the relationship between LV geometry and hospital mortality in patients with mitral regurgitation (MR) undergoing mitral valve surgery. METHODS: A consecutive series of patients (aged 68+/-12 years, 47% men) (n = 149) with MR who underwent cardiac catheterization, left ventriculography, and mitral valve surgery from 1995 to 1996 at Mount Sinai Medical Center was studied. Left ventriculograms, clinical records, and hemodynamics were reviewed. Left ventricular volumes and ejection fraction were calculated using standard techniques. Left ventricular shape in diastole and systole was evaluated using the sphericity index, which is defined as the end-systolic LV volume (x 100) divided by the volume of a sphere whose diameter is equal to the LV long axis. RESULTS: In the patients studied, the etiology of mitral insufficiency was mitral valve prolapse in 40.9%, ischemic heart disease in 40.3%, rheumatic heart disease in 11.4%, and prosthetic valvular dysfunction in 7.4%. The average ejection fraction was 65%+/-17. Systolic sphericity index (SSI) was 36%+/-15 in patients who died, compared with 25%+/-11 in patients who lived (p < 0.001). A multivariate model was constructed using hemodynamic and angiographic indices derived during preoperative cardiac catheterization. Systolic sphericity index (odds ratio = 1.6 for each point increase, p < 0.01) was found to be an independent predictor of postoperative survival in the global population, as well as in patients with coronary disease (p<0.01). CONCLUSION: Left ventricular geometry is an independent angiographic risk factor for survival following mitral valve replacement. Sphericity index is a simple method for assessing LV geometry which should be calculated in patients as part of risk stratification.     

Left ventricular response to isometric exercise and its value in predicting the change in ventricular function after mitral valve replacement for mitral regurgitation

Reduced left ventricular (LV) afterload and its effect on the resting ejection fraction may lead to over-estimation of LV function in mitral regurgitation (MR). To evaluate LV function during increased afterload of the heart, an isometric handgrip test was performed during cardiac catheterization in 15 patients with mitral regurgitation (MR group) and in 9 normal subjects (normal group). Twelve months after successful mitral valve replacement (MVR) the patients were recatheterized, and the value of preoperative stress testing in predicting the change in resting ventricular function after surgery was estimated.Isometric exercise caused an increase in end-systolic wall stress, a measure of ventricular afterload, in both the MR group and the control group (p < 0.001). The ejection fraction remained unchanged in the control group, but decreased from 0.58 ± 0.08 to 0.53 ± 0.08 in the MR group (p < 0.001). After MVR, end-systolic wall stress increased significantly (p < 0.001) and the ejection fraction decreased from 0.58 ± 0.05 to 0.51 ± 0.1 (p < 0.05). A positive correlation existed between the change in the ejection fraction during preoperative stress testing and the change in the resting ejection fraction after MVR (r = 0.65, p < 0.01). In 8 patients whose resting ejection fraction was within normal limits (> 0.55) preoperatively, the ejection fraction was depressed (< 0.55) 1 year after surgery. In all but 1 of these patients the isometric exercise revealed the reduced ventricular response to afterload stress preoperatively (decrease of the ejection fraction > 0.03 during exercise). Therefore, the isometric exercise-induced change in LV function appears to predict the influence of MVR on LV function.     

Determinants of subsequent late postoperative left ventricular function and reversal of ventricular dilatation after mitral valve replacement for chronic mitral regurgitation.

We studied 16 patients with chronic mitral regurgitation by echocardiography before, and at 3 weeks, at 6-8 months and at 1-9 years after mitral valve replacement (MVR) to investigate serial changes in left ventricular (LV) function and reversal of ventricular dilatation. All patients at an average of 2.6 years after, and 8 patients before MVR were also studied by echocardiography and, except for 3 patients by measuring plasma catecholamines from the right atrium during bicycle exercise. Before operation, all patients were divided into group A (n = 12) with end-systolic dimension (ESD) < 4 cm and systolic blood pressure (SBP)/ESD > 3, and group B (n = 4) with ESD > 4 cm and SBP/ESD < 3. Maximum reduction in end-diastolic dimension (EDD) occurred at 3 weeks in all patients after MVR (from 60.5 +/- 3.7 to 49.0 +/- 4.5 mm, p < 0.05). ESD was reduced significantly (p < 0.5) only in group A. LV function was normal in group A, but it was depressed in group B at early and late periods after MVR. The slopes of the relationship between the mean velocity of circumferential fiber shortening (Vcf) and plasma norepinephrine (NE) during exercise in all patients in group B decreased along with the depression in LV function. After operation, all patients in group A reached New York Heart Association (NYHA) functional class I, while patients in group B were in NYHA class II. It is concluded that the surgical outcome after MVR for chronic MR will be better if preoperative ESD < 4 cm and SBP/ESD > 3. The relationship between mean Vcf and plasma NE during exercise seemed to be a useful index to evaluate the inotropic reserve of the LV.     

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.     

Midterm outcomes of rheumatic mitral repair versus replacement

Mitral repair is feasible for patients with degenerative or ischemic heart disease, however, the appropriateness of repair for rheumatic heart disease remains controversial. We compared our outcomes for primary isolated mitral repair versus replacement in an elderly population. From November 1997 to July 2005, mitral repair (group I) was performed in 33 patients while 59 underwent replacement (group II). Survival and risk factors were evaluated by Kaplan-Meier and Cox regression analysis. Mean age at operation for groups I and II was 49.7 +/- 13.2 versus 58.1 +/- 11.2 (P = 0.002). No statistically significant differences with regards to demographic parameters were observed except for there being fewer percutaneous transvenous mitral commissurotomy procedures and a lower severity of pulmonary hypertension in group I. Patients with a greater Wilkins score and more valvular calcification underwent replacement more often (P < 0.001). In-hospital mortality, ICU/hospital stay, and postoperative congestive heart failure functional class did not differ significantly. Major adverse cardiac events occurred in 13 and 19 patients, respectively (P = 0.50). There were 4 versus 6 late deaths (P = 0.74). Only two from group I underwent subsequent mitral reoperation. Kaplan-Meier overall survival and event-free survival at 5 years for groups I and II were 0.81 +/- 0.08 versus 0.81 +/- 0.06 (P = 0.90) and 0.52 +/- 0.10 versus 0.51 +/- 0.10 (P = 0.21), respectively. Old age, renal insufficiency, LVEF < 40%, and a history of stroke were poor predictors of patient survival. Compared with replacement, mitral repair for rheumatic heart disease was associated with a lower surgical mortality, higher repeat-surgery rate, and good survival. Rheumatic mitral valves should be repaired in select patients with appropriate valvular pathology.     

Early and late results of restrictive mitral valve annuloplasty in 121 patients with cardiomyopathy and chronic mitral regurgitation

OBJECTIVE: This study investigated the early and late results of restrictive mitral valve (MV) annuloplasty in patients with chronic mitral regurgitation (MR) and advanced ischemic (ICM) or dilated cardiomyopathy (DCM). METHODS: From October 2001 to September 2006, 121 patients (age: 69 +/- 9 years) with a left ventricular ejection fraction (LVEF) of 30 +/- 9 % and chronic MR grade 3 - 4 (ICM: n = 102, DCM: n = 19) underwent restrictive prosthetic ring annuloplasty (downsizing of 2.7 +/- 0.8 ring sizes). Eighty-five ICM-patients had indications for concomitant coronary artery bypass grafting (CABG). All patients were restudied at 7 +/- 1 days, 3 +/- 1 and 30 +/- 12 months after surgery to assess survival, residual MR, New York Heart Association (NYHA) class and left ventricular (LV) function (end-systolic/end-diastolic dimensions/volume indexes and LVEF). Data were analyzed exploratively. RESULTS: 30-day mortality was 3.3 %; survival at follow-up was 95 % and 91 %, respectively. Postoperative recurrence of significant MR (> grade 2) was absent in all patients. NYHA class, LV dimensions/volume indexes and LVEF improved significantly after surgery in both groups ( P < 0.0005). A prediction of continuous postoperative improvement of myocardial function in the sense of reverse remodeling could be demonstrated by univariate logistic regression for ischemic etiology and concomitant CABG ( P = 0.0001). In DCM-patients or ICM-patients without CABG, the postoperative benefit on myocardial function was limited. CONCLUSION: Restrictive mitral valve (MV) annuloplasty corrected chronic MR in cardiomyopathy patients with low mortality and improved contractility. Surgery also prevented recurrence of significant MR, although the phenomenon of postoperative continuous reverse myocardial remodeling could not be verified in cases with a non-ischemic etiology or ICM without concomitant CABG.