Mitral valvuloplasty is superior to valve replacement for preservation of left ventricular function: an intraoperative two-dimensional echocardiographic study

Cardiac reverse remodeling in primary mitral regurgitation: mitral valve replacement vs. mitral valve repair

BACKGROUND

When feasible, guidelines recommend mitral valve repair (MVr) over mitral valve replacement (MVR) to treat primary mitral regurgitation (MR), based upon historic outcome studies and transthoracic echocardiography (TTE) reverse remodeling studies. Cardiovascular magnetic resonance (CMR) offers reference standard biventricular assessment with superior MR quantification compared to TTE. Using serial CMR in primary MR patients, we aimed to investigate cardiac reverse remodeling and residual MR post-MVr vs MVR with chordal preservation.

METHODS

83 patients with ≥ moderate-severe MR on TTE were prospectively recruited. 6-min walk tests (6MWT) and CMR imaging including cine imaging, aortic/pulmonary through-plane phase contrast imaging, T1 maps and late-gadolinium-enhanced (LGE) imaging were performed at baseline and 6 months after mitral surgery or watchful waiting (control group).

RESULTS

72 patients completed follow-up (Controls = 20, MVr = 30 and MVR = 22). Surgical groups demonstrated comparable baseline cardiac indices and co-morbidities. At 6-months, MVr and MVR groups demonstrated comparable improvements in 6MWT distances (+ 57 ± 54 m vs + 64 ± 76 m respectively, p = 1), reduced indexed left ventricular end-diastolic volumes (LVEDVi; - 29 ± 21 ml/m2 vs - 37 ± 22 ml/m2 respectively, p = 0.584) and left atrial volumes (- 23 ± 30 ml/m2 and - 39 ± 26 ml/m2 respectively, p = 0.545). At 6-months, compared with controls, right ventricular ejection fraction was poorer post-MVr (47 ± 6.1% vs 53 ± 8.0% respectively, p = 0.01) compared to post-MVR (50 ± 5.7% vs 53 ± 8.0% respectively, p = 0.698). MVR resulted in lower residual MR-regurgitant fraction (RF) than MVr (12 ± 8.0% vs 21 ± 11% respectively, p = 0.022). Baseline and follow-up indices of diffuse and focal myocardial fibrosis (Native T1 relaxation times, extra-cellular volume and quantified LGE respectively) were comparable between groups. Stepwise multiple linear regression of indexed variables in the surgical groups demonstrated baseline indexed mitral regurgitant volume as the sole multivariate predictor of left ventricular (LV) end-diastolic reverse remodelling, baseline LVEDVi as the most significant independent multivariate predictor of follow-up LVEDVi, baseline indexed LV end-systolic volume as the sole multivariate predictor of follow-up LV ejection fraction and undergoing MVR (vs MVr) as the most significant (p < 0.001) baseline multivariate predictor of lower residual MR.

CONCLUSION

In primary MR, MVR with chordal preservation may offer comparable cardiac reverse remodeling and functional benefits at 6-months when compared to MVr. Larger, multicenter CMR studies are required, which if the findings are confirmed could impact future surgical practice.

Mitral Regurgitation in the High-Risk Patient: Integrating an Expanding Armamentarium of Transcatheter Devices Into the Treatment Algorithm

Over the last decade, multiple transcatheter mitral valve repair and replacement strategies have emerged, yet there is only 1 US Food and Drug Administration approved device, the MitraClip (Abbott Vascular, Inc., Santa Clara, CA). Current guidelines support the use of the MitraClip in high or prohibitive surgical risk patients, but there are many patients that are not anatomically suited for the device. This review article discusses the approach to degenerative and functional mitral regurgitation in the high-prohibitive risk patient, how to choose transcatheter treatment options (both approved and investigational), and potential management for therapy failure.

Mitral valve repair in children with rheumatic heart disease

Purpose

Rheumatic heart disease is the most common acquired heart disease in children in developing countries. The heart valve lesions produce severe hemodynamic changes due to scarring of the valves over time. Around 15.6 million people are affected by rheumatic heart disease (RHD), and 230,000 die around the globe annually. Valve repair should be the primary goal, although it is technically challenging because of the fact that rheumatic process evolves making repair outcomes variable.

Methods

We reviewed the literature for the various techniques done for mitral valve repair in children with rheumatic heart disease. Early and late results of repair were compared with the results found for mitral valve repair done for such children.

Results

Prosthetic heart valve implantation in children has major negative impact on their immediate- and long-term survival as well as on quality of their life. Valve repair is associated with improved ventricular function because the normal valve tissue and subvalvular apparatus are preserved, reduced complications related to prosthetic valve, and lower in-hospital and late mortality.

Conclusion

In children, the results of mitral valve replacement were found to be inferior to those of mitral valve repair. The reoperation rates are similar in patients undergoing initial repair or replacement, which favors repair as an option. In developing world, rheumatic mitral valve disease is more prevalent where adequate facilities for monitoring of prosthetic valve function and management of anticoagulation therapy are not easily available. Valve repair therefore should be the primary goal.

Antithrombotic Management of Patients With Prosthetic Heart Valves

Valvular heart disease is a major public health issue. The prevalence of valvular heart disease is expected to increase due to an aging population. Valve dysfunction manifests as valve stenosis, regurgitation, or both due to various etiologies. Valve repair and replacement are the main treatment options for severe valve dysfunction. Valve replacement is achieved by using either a mechanical or a bioprosthetic valve. Mechanical valves are more durable but require lifelong anticoagulation with associated complications. Bioprosthetic valves usually require anticoagulation only transiently after implantation but are less durable and degenerate more rapidly. In this article, we discuss antithrombotic regimens in persons after valve operations. We discuss general issues and antithrombotic recommendations for patients undergoing surgical bioprosthetic valve replacement, mechanical valve replacement (including different regimens for different positions and types of mechanical valves), mitral valve repair, and transcatheter aortic valve replacement. In addition, we discuss the antithrombotic management of patients in special circumstances, including patients with mechanical valves who have recurrent bleeding or thrombotic events, patients with mechanical valves undergoing surgery, and pregnant women with mechanical valves.

Mitral Valve Repair: The French Correction Versus the American Correction

Degenerative mitral valve disease causing mitral regurgitation is the most common organic valve pathology and is classified based on leaflet motion. The "French correction" mitral valve repair method restores normal valvular anatomy with extensive leaflet resection, chordal manipulation, and rigid annuloplasty. The American correction attempts to restore normal valve function through minimal leaflet resection, flexible annuloplasty, and use of artificial chordae. These differing methods of mitral valve repair reflect an evolution in principles, but both require understanding of the valve pathology and correction of leaflet prolapse and annular dilatation. Adhering to those unifying principles and ensuring that no patient leaves the operating room with significant persistent mitral regurgitation produces durable results and satisfactory patient outcomes.

Mitral Valve Annuloplasty Rings: Review of Literature and Comparison of Functional Outcome and Ventricular Dimensions

In the past decades, more than 40 mitral valve annuloplasty rings of various shapes and consistency were marketed for mitral regurgitation (MR), although the effect of ring type on clinical outcome remains unclear. Our objective was to review the literature and apply a simplification method to make rings of different shapes and rigidity more comparable. We studied relevant literature from MEDLINE and EMBASE databases related to clinical studies as well as animal and finite element models. Annuloplasty rings were clustered into 3 groups as follows: rigid (R), flexible (F), and semirigid (S). Only clinical articles regarding degenerative (DEG) or ischemic/dilated cardiomyopathy (ICM) MR were included and stratified into these groups. A total of 37 rings were clustered into R, F, and S subgroups. Clinical studies with a mean follow-up of less than 1 year and a reported mean etiology of valve incompetence of less than 60% were excluded from the analysis. Forty-one publications were included. Preimplant and postimplant end points were New York Heart Association class, left ventricular ejection fraction (LVEF), left ventricular end-systolic dimension (LVESD), and left ventricular end-diastolic dimension (LVEDD). Statistical analysis included paired-samples t test and analysis of variance with post hoc Bonferroni correction. P < 0.05 indicated statistical difference. Mean ± SD follow-up was 38.6 ± 27 and 29.7 ± 13.2 months for DEG and ICM, respectively. In DEG, LVEF remained unchanged, and LVESD decreased in all subgroups. In our analysis, LVEDD decreased only in F and R, and S did not change; however, the 4 individual studies showed a significant decline. In ICM, New York Heart Association class improved in all subgroups, and LVEF increased. Moreover, LVESD and LVEDD decreased only in F and S; R was underpowered (1 study). No statistical difference among R, F, and S in either ICM or DEG could be detected for all end points. Overall, owing to underpowered data sets derived from limited available publications, major statistical differences in clinical outcome between ring types could not be substantiated. Essential end points such as recurrent MR and survival were incomparable. In conclusion, ring morphology and consistency do not seem to play a major clinical role in mitral valve repair based on the present literature. Hence, until demonstrated otherwise, surgeons may choose their ring upon their judgment, tailored to specific patient needs.

Mitral chordal-leaflet-myocardial interactions in mitral valve prolapse

BACKGROUND

The submitral apparatus maintains annular-papillary continuity and myocardial geometry. In mitral valve prolapse (MVP), elongated chords and redundant leaflets can interact at the region of myocardial attachment, leading to apparent discordant motion of the basal inferolateral wall. The aim of this study was to test the hypothesis that basal inferolateral wall inward motion would occur later in MVP and that this delay is associated with MVP severity.

METHODS

Thirty consecutive patients with MVP and matched controls underwent stress echocardiography. Time to peak transverse displacement (TPD) of the inferolateral wall compared with the anteroseptal wall was measured using speckle-tracking echocardiography. The time difference was analyzed as raw data, normalized to the RR interval, and as a percentage of the time to maximal displacement of the anteroseptal segment(s).

RESULTS

Compared with controls, TPD was delayed in patients with MVP both at rest and at peak stress, when evaluating basal segments or basal-mid segments as a unit, both in real time and, more importantly, when correcting for anteroseptal TPD. In patients compared with controls, observed delay at rest and at peak stress was 50 ± 90 versus -30 ± 90 msec (P = .006) and 70 ± 80 versus -30 ± 60 msec (P < .0001), respectively; relative to TPD of the anteroseptal segment, the observed delay at rest and at peak stress was 117 ± 24% versus 97 ± 22% (P = .007) and 144 ± 68% versus 95 ± 21% (P = .003), respectively. Similar significant findings were observed in basal-mid segments. TPD results were not statistically significant when stratified by prolapse severity. Intraclass correlation coefficients were 0.88 and 0.93, and two-tailed t tests indicated good interobserver and intraobserver variability.

CONCLUSIONS

Inferolateral wall TPD is delayed in MVP. TPD is a novel method to characterize chordal-leaflet-myocardial interactions in patients with MVP. Prolapse severity does not predict TPD, likely because of the timing of prolapse and dynamic loading conditions. Implications of this observation include attribution of a perceived wall motion abnormality in MVP during stress echocardiography to a physiologic state and new mechanistic insights into mitral valve physiology.

Advances in percutaneous valvular intervention

We are entering a new era in the percutaneous treatment of valvular heart disease. Novel techniques and devices have given rise to the possible treatment of a range of valvular heart diseases that previously necessitated surgical therapies, including aortic stenosis, pulmonary regurgitation and mitral regurgitation. Despite the enormous potential of these percutaneous therapies, enthusiasm needs to be balanced by an understanding of the challenges that need to be overcome before such therapies can be widely embraced. This review provides a critical assessment of the status of the major developments in percutaneous valvular intervention to date, and provides the authors' perspective on the current role and future potential of these techniques.

[Coronary CTA evaluation of the relationship between mitral valve annulus and coronary circulation: implications for percutaneous mitral annuloplasty]

PURPOSE

To evaluate anatomical relationships between mitral annulus (MA), coronary arteries and coronary sinus (CS) in two groups of patients with and without moderate mitral insufficiency on coronary CTA to identify candidates to percutaneous mitral valve annuloplasty via the coronary sinus without risk of coronary artery occlusion. MATERIALS AND METHODS. Fifty-one ECG-gated coronary CTA examinations, obtained during injection of iodinated contrast material on a 16 MDCT were retrospectively reviewed. The mitral valve annulus diameter, anatomical relationships between CS and coronary arteries and MA-CS distance were compared between both patient groups.

RESULTS

The group with mitral insufficiency included 16 patients and the control group included 35 patients. The AP diameter of the MA was 45,7+/-5,2 mm in the group with mitral insufficiency, significantly larger (p=0.0009) compared to the control group (39,3+/-5,9 mm). In 70.4% of cases, the CS was located next to a coronary artery in an overlapping configuration. The unfavorable anatomical configuration with regards to annuloplasty appeared related to mitral insufficiency (p=0.0539). The distance between MA and CS was greatly variable with the CS routinely extending over the left atrial surface: the distance was significantly (p=0.0002) greater for all patients along the posterior surface (8,1+/-3,8 mm) compared to the lateral surface (5,2+/-4,6 mm) with this différence persisting within both groups: p=0.004 for patients with mitral insufficiency and p=0.0001 for control patients.

CONCLUSION

Our results demonstrate the value of coronary CTA in selecting candidates to percutaneous mitral annuloplasty. In 70.4% of cases, the CS overlaps a coronary artery with risk of compression at the time of annuloplasty.

The evaluation of real-time 3-dimensional transthoracic echocardiography for the preoperative functional assessment of patients with mitral valve prolapse: a comparison with 2-dimensional transesophageal echocardiography

OBJECTIVE

We sought to compare the feasibility and accuracy of transthoracic real-time 3-dimensional echocardiography (RT-3DE) with transesophageal echocardiography (TEE) for the preoperative functional assessment of patients with mitral valve prolapse.

METHODS

In 44 patients with severe mitral regurgitation caused by type 2 valve dysfunction, TEE and RT-3DE were performed 24 hours before surgery and analyzed by two separate observers. TEE and RT-3DE images were acquired digitally and stored for offline analysis. The echocardiographic results were validated intraoperatively.

RESULTS

Five patients did not have image quality suitable for analysis with RT-3DE and were excluded from analysis, leaving a sample size of 39. In total, 54 of 334 analyzed mitral valve segments were diseased. Prolapse of a single mitral valve segment was present in 25 patients and 14 patients had complex disease involving two or more segments. Sensitivity, specificity, and accuracy for TEE in identification of diseased segments were 94%, 100%, and 96%, respectively. The same values for RT-3DE were 91%, 100%, and 94%, respectively. The differences were not statistically significant. Accuracies were not significantly different according to segment location. Interobserver agreement was 92% for TEE and 88% for RT-3DE (P = nonsignificant).

CONCLUSIONS

RT-3DE is feasible with comparative accuracy to TEE for precise anatomic localization of prolapsing mitral valve segments. However, the technique is limited by poor image quality in 11% of patients.

Future Directions in Degenerative Mitral Valve Repair

Mitral valve repair is by far the most common operation for degenerative mitral regurgitation. If the procedure is performed before left ventricular dysfunction occurs and atrial fibrillation develops, the operative risk is very low and life expectancy is super imposable to that of the sex- and age-matched population. Despite these achievements, there are areas that could still be improved. Progress in treating degenerative mitral regurgitation is expected to move along several directions. More precise diagnostic methods will be developed to reliably quantify mitral regurgitation and identify early irreversible ventricular and atrial changes. The refinement of surgical techniques and search for new, innovative solutions should never be abandoned. Finally, transcatheter correction of mitral regurgitation represents a new, emerging field of cardiovascular medicine and is expected to have a significant impact on the surgical practice in the future.

In Vivo Analysis of the Anatomical Relationship of Coronary Sinus to Mitral Annulus and Left Circumflex Coronary Artery Using Cardiac Multidetector Computed Tomography

OBJECTIVES

We sought to determine the in vivo anatomical relationships between mitral annulus (MA) and coronary sinus (CS) as well as CS and left circumflex coronary artery using cardiac computed tomography.

BACKGROUND

Percutaneous treatment of mitral regurgitation (MR) by annuloplasty via CS is under development. Success of such treatment depends on the close anatomical proximity of the MA to the CS. The in vivo data regarding this anatomical relationship in humans are scant. We investigated this relationship using contrast multidetector computed tomography.

METHODS

We studied 25 normal individuals and 11 patients with severe MR (3 to 4+) due to mitral valve prolapse. Separation between MA and CS was measured in standard planes, in 4-chamber (4C), 2-chamber (2C), and 3-chamber views. Distance from ostium of CS to the intersection with left circumflex (LCX), and anatomical relation of LCX and CS were determined using 3-dimensional mapping (Philips Brilliance, Philips Medical Systems, Amsterdam, the Netherlands).

RESULTS

There was significant variance of CS to MA separation at all planes. Separation of CS and MA was increased in lateral location (4C) and decreased in posterior location (2C) in the MR group with increase in MA size. Left circumflex artery crossed between CS and MA in 80% of patients. The LCX crossed CS at a variable distance from the ostium of CS (86.5 +/- 21 mm, range 37 to 123 mm)

CONCLUSIONS

There is significant variability in the relation of CS to MA in humans. Coronary sinus to MA distance increases in patients with severe MR and annular dilation, mainly in the posterolateral location. The left circumflex crosses under the CS the majority of times, but with a significant variability in the location where it crosses the CS. These anatomical features should be taken into consideration while selecting percutaneous treatment strategies for mitral valve repair.

Effect of training in mitral valve repair surgery on the early and late outcome

BACKGROUND

Preservation of the native mitral valve provides important advantages over valve replacement. The aim of this study was to evaluate the effect of training for mitral valve repair on the outcome.

METHODS

Between 1997 and 2004, 471 patients underwent mitral valve repair procedures in a single firm. Of these procedures, 300 (64%) were performed by a consultant (TJS) (consultant group) and 171 (36%) by trainees supervised by the same consultant (trainees group).

RESULTS

Atrial fibrillation was more prevalent in the consultant group (p = 0.02) but there were no significant differences in the demographics, etiology of mitral regurgitation, and other comorbidity between the groups. Posterior leaflet prolapse was more prevalent in the trainees group (p < 0.0001) and anterior leaflet prolapse (p < 0.0001), bileaflet prolapse (p = 0.003), and Barlow's syndrome (p = 0.0003) in the consultant group. The consultant performed a higher proportion of concomitant coronary artery bypass grafting (p = 0.04), aortic valve replacement (p = 0.02), procedures, and nonelective cases (p = 0.03) with shorter bypass (p = 0.01) and ischemic times (p = 0.0004) than trainees. The complication rate was similar in the two groups (26% vs 22%), but the consultant had a higher operative mortality than the trainees (5% vs 0.6%) (p = 0.01). A similar proportion in the two groups exhibited recurrent mitral regurgitation (8% vs 9%). Kaplan-Meier five-year freedom from reoperation (95.6 +/- 1.6 vs 95.7 +/- 2.2%) (p = 0.7) and survival (82 +/- 4% vs 88 +/- 4%) (p = 0.09) were similar in the two groups.

CONCLUSIONS

With appropriate patient selection, cardiothoracic trainees can be taught mitral valve repair surgery without a negative effect on the early or late outcome.

Surgical alternatives for the palliation of heart failure: a prospectus

BACKGROUND

Congestive heart failure (CHF) is the leading cause of hospital admissions in the United States.

METHODS AND RESULTS

CHF has a variety of palliative options for treatment and 1 curative one: cardiac transplantation. Palliative medical therapies are often limited in effectiveness by progression of the disease or patient intolerance. Because of limited donor availability, alternative surgical strategies are now being relied on for palliation of patients in end-stage CHF.

CONCLUSION

In this manuscript, we review the principles, outcomes, and practices of some of these surgical strategies often used in the palliation of end-stage CHF.

Similar long-term results of mitral valve repair for anterior compared with posterior leaflet prolapse

OBJECTIVE

The results of mitral valve repair for anterior leaflet prolapse have been less gratifying than those reported for posterior leaflet prolapse. We compared the long-term durability of 2 different surgical techniques: the edge-to-edge repair, which is used for the treatment of anterior leaflet prolapse, and quadrangular resection, which has been adopted for correction of posterior leaflet prolapse.

METHODS

From 1991 through April 2004, 133 patients with anterior leaflet prolapse and 605 with posterior leaflet prolapse caused by degenerative mitral disease underwent valve repair. The edge-to-edge repair was used for correction of anterior leaflet prolapse, and quadrangular resection of the posterior leaflet, with or without sliding plasty, was used for correction of posterior leaflet prolapse. All patients received a concomitant annuloplasty procedure.

RESULTS

No hospital deaths occurred in the anterior leaflet prolapse group, whereas 2 (0.3%) patients died in the posterior leaflet prolapse group (P = .7). Follow-up was 100% and 97.2% complete in the anterior and posterior leaflet prolapse groups, respectively. At 10 years, overall survival was 91% +/- 4.06% for anterior leaflet prolapse and 93.5% +/- 1.81% for posterior leaflet prolapse (P = .18), and freedom from cardiac death was 95.8% +/- 2.83% for anterior leaflet prolapse and 97.4% +/- 0.95% posterior leaflet prolapse (P = .27). Freedom from reoperation was 96% +/- 2.3% in the anterior leaflet prolapse group and 96.5% +/- 1.18% in the posterior leaflet prolapse group (P = .37). At follow-up (mean, 4.5 +/- 3.12 years; range, 1 month-13.2 years), New York Heart Association functional class I or II was documented in 93.2% of patients in the anterior leaflet prolapse group and 92.8% in the posterior leaflet prolapse group (P = .98).

CONCLUSIONS

The long-term results of the edge-to-edge repair in the setting of anterior leaflet prolapse are similar to those obtained with quadrangular resection for the treatment of posterior leaflet prolapse.

Mitral valve repair for active culture positive infective endocarditis

OBJECTIVE

To describe the clinical and echocardiographic outcome after mitral valve (MV) repair for active culture positive infective MV endocarditis.

PATIENTS AND METHODS

Between 1996 and 2004, 36 patients (mean (SD) age 53 (18) years) with positive blood culture up to three weeks before surgery (or positive culture of material removed at operation) and intraoperative evidence of endocarditis underwent MV repair. Staphylococci and streptococci were the most common pathogens. All patients had moderate or severe mitral regurgitation (MR). Mean New York Heart Association (NYHA) class was 2.3 (1.0). Follow up was complete (mean 38 (19) months).

RESULTS

Operative mortality was 2.8% (one patient). At follow up, endocarditis has not recurred. One patient developed severe recurrent MR and underwent valve replacement and one patient had moderate MR. There were two late deaths, both non-cardiac. Kaplan-Meier five year freedom from recurrent moderate to severe MR, freedom from repeat operation, and survival were 94 (4)%, 97 (3)%, and 93 (5)%, respectively. At the most recent review the mean NYHA class was 1.17 (0.3) (p < 0.0001). At the latest echocardiographic evaluation, left atrial diameters, left ventricular end diastolic diameter, and MV diameter were significantly reduced (p < 0.05) compared with preoperative values.

CONCLUSIONS

MV repair for active culture positive endocarditis is associated with low operative mortality and provides satisfactory freedom from recurrent infection, freedom from repeat operation, and survival. Hence, every effort should be made to repair infected MVs and valves should be replaced only when repair is not possible.

Anterior Leaflet Repair With Patch Augmentation for Mitral Regurgitation

BACKGROUND

Anterior leaflet repair continues to pose significant operative challenges, particularly in patients with retracted or "short" anterior leaflets, due to rheumatic or radiation induced mitral valve disease. This often results in abandonment of repair in favor of mitral valve replacement, requiring anticoagulation and altering left ventricular (LV) function and geometry. This study examines our experience of anterior leaflet repair with patch augmentation.

METHODS

Forty-two patients underwent mitral valve repair for a shortened anterior leaflet from 1994 to 2003. Twenty-two patients with a mean age of 53 +/- 6 years had radiation valvulitis (XR) whereas 20 patients, age 28 +/- 7 years had rheumatic heart disease (RHD). Those patients with XR had a mean New York Heart Association (NYHA) class of 3.2 +/- 0.4 and an angina score of 2.1 +/- 0.6 compared with a NYHA class 3.8 +/- 0.2 and no angina in RHD patients. All patients presented with severe MR. Anterior leaflet augmentation with a gluteraldehyde-treated, autologous pericardial patch and complete annuloplasty ring was used in all patients. Additionally, extensive subvalvar debridement was performed in RHD patients. Twelve XR patients underwent concomitant CABG with a mean of 2.4 +/- 0.8 grafts/patient. Additional surgical procedures included tricuspid valve repair, anterior septal defect, and aortic valve replacement. Mean follow-up was 39 +/- 10 months for XR patients and 12 +/- 25 months for RHD patients.

RESULTS

There were two late deaths in XR patients from underlying malignancies and no deaths in RHD patients. Two RHD patients required reoperation for recurrent mitral regurgitation at 3 and 20 months. All patients demonstrated clinical improvements (NYHA I-II) following repair. No mitral stenosis was induced.

CONCLUSIONS

Despite anterior leaflet shortening from XR or rheumatic alterations, opportunity still exists for gratifying mitral valve repair. By utilizing anterior leaflet patch augmentation, concomitantly with ring annuloplasty, anticoagulation is avoided, LV geometry is preserved, and follow-up reveals excellent functional improvement.

Long-term Assessment of Mitral Valve Reconstruction With Resection of the Leaflets: Triangular and Quadrangular Resection

BACKGROUND

The procedure of quadrangular resection and suture for prolapsed posterior leaflet of the mitral valve is a reliable and reproducible method that achieves excellent long-term results. However, triangular resection and suture of a prolapsed anterior leaflet is not widely supported and different techniques have been advocated. The aim of this study was to review our experience of mitral valve repair in which resection of the anterior and/or posterior leaflets was performed.

METHODS

Between October 1991 and September 2003, 105 patients with mitral regurgitation underwent mitral valve reconstruction with leaflet resection, including 55 patients with quadrangular resection of the posterior leaflet (P), 32 patients with triangular resection of the anterior leaflet (A), and 18 patients with resection of both leaflets (A+P).

RESULTS

The mean follow-up period was 63.6 (1 to 139) months. Reoperation was required in 2 patients, each after resection of the anterior or posterior leaflet. The freedom from reoperation rates at 10 years in 93% +/- 5% of patients after triangular resection of the anterior leaflet, 96% +/- 3% after quadrangular resection of the posterior leaflet, and 100% after resection of both leaflets. There were no significant differences of survival or risk of reoperation among these three groups. The postoperative mitral valve area was significantly smaller than the preoperative area in all three groups, but remained large enough (A: 2.84 +/- 1.07; P: 2.6 +/- 0.87; A+P: 3.09 +/- 1.20 cm2) for adequate valve function.

CONCLUSIONS

Triangular resection of a prolapsed anterior mitral leaflet is a reliable, reproducible, and durable procedure, like quadrangular resection of a prolapsed posterior leaflet.

Update on Mitral Repair in Dilated Cardiomyopathy

Heart failure is one of the leading causes of hospitalization worldwide. Mitral regurgitation (MR) is a known complication of end-stage cardiomyopathy and is associated with a poor prognosis due to progressive mitral annular dilation. A vicious cycle of continuing volume overload, ventricular dilation, progression of annular dilation, increased LV wall tension, and worsening of MR and CHF occur. Commonly, these patients were managed medically with diuretics and afterload reduction, and frequently with mitral valve replacement, both of which have poor long term survival in patients with CHF and MR. Over a 10-year period we prospectively studied over 200 patients with cardiomyopathy and severe MR who underwent mitral valve repair utilizing an undersizing overcorrecting annuloplasty ring. The mortality was low with one intraoperative death and eight 30-day mortalities. There were 26 late deaths; 2 of these patients had progression of heart failure and underwent transplantation. The 1-, 2-, and 5-year actuarial survivals have been 82%, 71%, and 52%, respectively. The NYHA class has improved for all patients from a preoperative mean of 3.2 +/- 0.2 to 1.8 +/- 0.4 postoperatively. All patients demonstrated improvement in ejection fraction, cardiac output, and end diastolic volumes with a reduction in sphericity index and regurgitant volume at 2 years post operation. All of the observed changes contribute to reverse remodeling and restoration of the normal left ventricular geometry. Mitral valve repair is a safe and effective operative intervention that corrects MR and offers a new strategy for patients with MR and end-stage cardiomyopathy.

Catheter-Based Approach to Mitral Regurgitation

Mitral Regurgitation (MR) is a common medical problem. MR is also a prognostic factor; patients with severe symptomatic MR have a poor prognosis with an annual mortality rate of 5% without surgical intervention. An anatomic understanding of the normal and regurgitant mitral valve is essential in order to evaluate appropriately the severity and impact of MR. We briefly discuss mitral complex anatomy, MR evaluation, and treatment options (surgical and catheter-based alternatives) according to the type of lesion found. In particular, our group has shown temporal percutaneous annuloplasty and definitive percutaneous edge-to-edge mitral valve repair to be a feasible technique. Recently a study evaluating endovascular mitral valve edge-to-edge repair was successfully initiated by our group. Acute and chronic ischemic mitral regurgitation and special situations, such as paravalvular leaks, hypertrophic obstructive cardiomyopathy, and mixed lesions are also discussed. Future directions may include the percutaneous transcatheter implantation of a bioprosthetic valve in mitral position.