Severe calcification does not affect long-term outcome of mitral valve repair

Noncontrast cardiac computed tomography-derived mitral annular calcification scores in mitral valve disease

BACKGROUND AND AIMS

Mitral annular calcification (MAC) by computed tomography (CT) is reported as an independent predictor of poor outcomes. However, it currently remains unclear if quantitative MAC parameters provide more value for mitral valve disease (MVD) management, therefore, we examined the prognostic value of MAC scores using noncontrast cardiac-CT in MVD patients.

METHODS

Between January 2020 and December 2021, we prospectively enrolled 300 consecutive patients with MVD (MAC-present = 80 and MAC-absent = 220) undergoing preoperative cardiac-CT and mitral valve (MV) surgery. Noncontrast cardiac-CT images were used to qualitatively detect MAC (present or absent) and evaluate MAC scores. For analyses, we also collected baseline clinical data, intraoperative conversion (from MV repair to MV replacement), and follow-up arrhythmia data.

RESULTS

Compared with the MAC-absent group, MAC-present patients were older (62 ± 7 vs. 58 ± 9 years, p < .001), mostly women (55% vs. 39.5%, p = .017), and also had aortic valve calcification (57.5% vs. 23.2%, p < .001), mitral stenosis (82.5% vs. 61.8%, p < .001), atrial fibrillation (30% vs. 11.8%, p < .001), and larger left atrial end-diastolic dimension (LADD, 49 [44-56] versus 46 [41-50], p = .001]. Furthermore, MAC-present patients underwent more MV replacements (61.8% vs. 82.5%, p = .001) and experienced a higher intraoperative conversion prevalence (11.8% vs. 61.3%, p < .001). Multiple logistic regression analyses showed that the female gender (odds ratio [OR]/95% confidence interval [CI]/p = 2.001/1.042-3.841/0.037) and MAC scores (OR/95% CI/p = 10.153/4.434-23.253/p < .001) were independent predictors of intraoperative conversion. During a follow-up of 263 ± 134 days, MAC-present patients had more arrhythmias (42.5% vs. 9.5%, p < .001). Also, MAC-scores (hazard ratio [HR]/95% CI/p = 6.841/3.322-14.089/p < .001) and LADD (HR/95% CI/p = 1.039/1.018-1.060/p < .001) were independently associated with arrhythmias by Cox regression analyses.

CONCLUSIONS

Noncontrast cardiac CT-derived MAC-scores showed a high risk for intraoperative conversion and follow-up arrhythmias in MVD-patients.

Mitral valve surgery with extensive annular calcification: review of surgical techniques and postoperative complications

Mitral annular calcification (MAC) represents an important risk factor in mitral valve (MV) surgery. Despite several procedures having been described, no surgical treatment of choice has been established so far: whether a decalcification should be systematically carried out, or if the MV should be preferentially repaired rather than replaced. A review of the literature on patients undergoing MV surgery associated with MAC was performed. Studies were excluded if dealing with endovascular procedures or emergency surgery for associated endocarditis. Case reports were also not considered in the final analysis. The literature search identified 1429 potentially eligible studies, and 25 papers were eventually included. Several surgical techniques were described to approach this challenging condition. During MV surgery, the presence of MAC favors the occurrence of suboptimal intraoperative outcomes. MAC-related complications such as atrioventricular groove rupture, cerebrovascular accident, new permanent pacemaker implantation, intraoperative conversion from valve repair to replacement and mortality were analyzed. MV surgery in the presence of MAC considerably impacts the postoperative outcomes in terms of morbidity and mortality. A great variability of surgical techniques is reported, suggesting the need for standardization of the approach.

Modified Transventricular and Transaortic Mitral Valve Edge-to-Edge Repair Mimicking MitraClip Overcorrection

Objective

In the current study, we present our mid-term experience with modified edge-to-edge repair technique through a transventricular and transaortic route in patients requiring left ventricular remodeling or aortic root/valve surgery.

Methods

From December 2006 through April 2015, 49 high-risk patients (median age: 69 years; median European System for Cardiac Operative Risk Evaluation II: 11.4 [6.54-14.9]) underwent transventricular (N = 7; 14%) or transaortic (N = 42; 86%) edge-to-edge mitral valve repair. The Alfieri stitch technique was modified by MitraClip type overcorrection and solid buttressing behind the posterior leaflet. Indication was grade 2+ functional mitral valve incompetence and dilated or impaired left ventricle (N = 25; 52%), or grade 3+ (N = 22; 45%) and grade 4+ functional mitral valve regurgitation (N = 2; 4%). Surgical procedure included aortic root surgery in 65%, aortic valve replacement with surgical revascularization in 18%, and Dor-plasty with surgical revascularization in 14%.

Results

Intraoperative mortality and early neurologic complications were absent in our series. Ninety-day mortality was 12.2% (N = 6). Median clinical and echocardiographic follow-up-time was 50.7 (21.5-44.1) and 39.2 (33.7-44.1) months, respectively. Median postoperative transvalvular gradient was low (2.72 [1.91-4.22] mm Hg) and did not increase during follow-up (P = .268), although peak gradient rose slightly from 7.41 to 8.12 mm Hg (P = .071). The actuarial reoperation free rate at the index valve was 96.8%.

Conclusions

Transventricular or transaortic Alfieri mitral repair mimicking mitral clip overcorrection represents a quick and safe technique in the setting of high-risk patients undergoing left ventricular remodeling or aortic root/valve surgery and can be performed with low risk of creating mitral stenosis at midterm. The technique is straightforward, with reliable identification of the center of the valve leaflets being the limitation.

Mitral annular calcification: challenges and future perspectives

Mitral annular calcification (MAC) is a chronic degenerative process that implies calcification on the mitral support structure. It usually appears as a bystander to other cardiac pathologies hindering surgical treatment and increasing morbidity and mortality. When addressing the mitral valve, many surgical strategies have been suggested in the past with no clear consensus on what to choose. Moreover, and as transcatheter therapies have gained popularity over the last few decades, transcatheter mitral valve implantation has appeared as another alternative to conventional surgery. In this review, we aim at describing an overview of MAC, highlighting current challenges and treatment options as well as new potential alternatives.

Mitral annulus calcification: current management and future challenges

Mitral annulus calcification is a chronic degenerative process in the fibrous base of the mitral valve. Assessment and treatment of mitral valve disease in patients with severe mitral annulus calcification is challenging, and a multimodal approach is helpful to delineate its severity and anatomic features, and to guide the therapeutic strategy. This article reviews the current literature to provide a clinically relevant description of mitral annulus calcification, analyze the diagnostic pathway of a patient with mitral annulus calcification, and summarize the therapeutic options.

Mitral valve repair versus replacement

Degenerative, ischemic, rheumatic and infectious (endocarditis) processes are responsible for mitral valve disease in adults. Mitral valve repair has been widely regarded as the optimal surgical procedure to treat mitral valve dysfunction of all etiologies. The supporting evidence for repair over replacement is strongest in degenerative mitral regurgitation. The aim of the present review is to summarize the data in each category of mitral insufficiency and to provide recommendations based upon this data.

Severe mitral annular calcification in rheumatic heart disease: A rare presentation

Severe mitral annular calcification (MAC) is frequently seen in patients with advanced age and chronic kidney disease, but it is rare in rheumatic heart disease (RHD). We hereby report a case of 45-year-old female with chronic RHD, who had severe MAC and mitral regurgitation. Fluoroscopy revealed a "crown"-like severe calcification of the mitral annulus. Autopsy of the heart revealed a calcified posterior mitral annulus, fused commissures, and calcified nodules at the atrial aspect of the mitral valve.

The use of autologous pericardium for complicated mitral valve annulus

The study aims to discuss annular repair using the autologous pericardial patch in cases with severe mitral ring calcification and endocarditis during mitral valve replacement. In the study, annular reconstruction was applied, during mitral valve replacement, to 8 patients who had extensive annular calcification or annular destruction due to endocarditis. After annular resection, a two-centimeter wide autologous pericardial patch was sutured continuously to the left ventricular wall close to the posterior annulus. After the valve sutures with pledgets were placed at the back of the pericardial patch, the other edge of the patch was sutured continuously to the left atrial posterior wall. Suturing was complete after the whole annulus was encircled. Thereafter, an appropriately sized mechanical prosthesis valve was used. One patient died postoperatively due to low cardiac output (early mortality 12.5%). Echocardiographical paravalvular leakage was not detected in any of the cases during follow-up. Annular dehiscence and other annular pathologies were also not detected. This reconstructive approach may positively influence mortality and morbidity in cases with complicated mitral pathologies.

Mitral valve surgery in patients with extensive calcification of the mitral annulus

OBJECTIVES

The objective of this work was to examine the clinical outcomes of mitral valve surgery in patients with extensive mitral annular calcification.

METHODS

Mitral valve surgery was performed in 54 patients (28 men and 26 women, mean age 63 +/- 14 years) with mitral regurgitation and extensive mitral annular calcification. Most patients (78%) were in New York Heart Association classes III and IV, 14 had coronary artery disease, and 9 had prior mitral valve replacement in which the calcium bar was not removed. The calcium bar was excised and a new mitral annulus was created by suturing a strip of pericardium onto the endocardium of the left ventricle from lateral to medial fibrous trigones and to the endocardium of the left atrium. The mitral valve was repaired in 12 patients and replaced in 42. In 23 patients the intervalvular fibrous body was reconstructed and the aortic valve was also replaced. Mean follow-up was 4.1 +/- 3.7 years and was complete.

RESULTS

There were 5 operative deaths and 11 late deaths. Five-year survival was 73 +/- 7%. Four patients needed reoperation and each survived. Freedom from reoperation at 5 years was 89 +/- 6%. Three patients had a stroke and 4 had anticoagulation-related hemorrhage, one of which was fatal. Five-year freedom from valve-related mortality or morbidity was 75 +/- 8%. Most survivors were in New York Heart Association functional classes II and III.

CONCLUSIONS

Resection of the calcium bar and creation of a new annulus with pericardium provided good clinical results in patients with extensive calcification of the mitral valve.

Valve repair in mitral regurgitation complicated by severe annulus calcification

BACKGROUND

Valvuloplasty has significant advantages over valve replacement for mitral regurgitation, but the presence of severe calcification of the mitral valve apparatus has been thought to preclude successful valve reconstruction in general. The purpose of this report is to assess the results of valvuloplasty in patients with severe mitral regurgitation having extensive calcification extending from the mitral annulus to underlying myocardium and parts of the papillary muscles.

METHODS

Thirty-seven adult patients with severe mitral regurgitation and calcification were operated on between April 1990 and January 1998. Twenty-six patients had degenerative disease, 4 had acute bacterial endocarditis, 6 had postrheumatic fever, and 1 patient had Marfan's disease. The valve repair comprised of en bloc decalcification with extensive leaflet debridement and reconstruction of the annulus. Autologous pericardium was used in patch-extended endocardial annuloplasty or leaflet repair. Valve competence was retained after correction of regurgitation by sliding atrioplasty, rotation paracommissural sliding plasty, cusp remodeling, or chordal repair. All patients required a prosthetic annuloplasty.

RESULTS

Follow-up echocardiography at 47 months (range, 3 to 92 months) showed no or only trivial mitral regurgitation in 33 patients; 3 had grade I-II mitral regurgitation and 1 required valve replacement after 3 months. Freedom of reoperation at 1 and 5 years was 94.6%. At last examination, 33 patients were in New York Heart Association functional class I and 3 in class I-II; there has been no mortality and no thromboembolic events.

CONCLUSIONS

Valvuloplasty can be safely and successfully carried out in patients suffering from regurgitation associated with severe calcification of the mitral apparatus. With encouraging beneficial midterm results, we suggest patients with calcified valves should not be excluded from mitral repair.

Mitral valve repair vs replacement. Current recommendations and long-term results

Techniques now exist to correct abnormalities of all components of the mitral valvular apparatus except extensive loss of pliable leaflet area. Thus, paradoxically, myxomatous valves with redundant leaflets represent the ideal candidates for mitral valve repair. Repair for mitral insufficiency can be performed for some rheumatic valves, but patient selection is critical. Loss of leaflet area, leaflet thickening, and extensive calcification of the leaflets or commissures are contraindications to repair. The abnormalities of the subvalvular apparatus are less important because a complete set of new chordae can be reconstructed using PTFE suture material. Some cases of endocarditis are ideal for repair using localized débridement and pericardial patch repair with or without PTFE chordal replacement. True ischemic mitral regurgitation of the Carpentier type I category is still something of a surgical enigma. Because it is a restrictive leaflet motion problem, annuloplasty alone is not always effective, and the outcome of any given repair attempt is less predictable. Repairs in patients with small annuli and multiple leaflet defects requiring complex series of maneuvers have a low probability of success. Furthermore, such patients with small left ventricular cavities are more prone to experience SAM. Several factors contributing to which therapy is chosen for mitral valve disease are summarized in Table 1. Patient selection, accurate evaluation of the cause or causes of mitral regurgitation, and well-executed application of the appropriate techniques for repair are all critical factors in the early and late success of mitral valve repair.

Reoperation after valve repair for mitral regurgitation: early and intermediate results

To better understand late outcomes of mitral valve repair, we reviewed the cases of 49 consecutive patients who underwent reoperation between January 1974 and May 1992 for recurrent valve dysfunction after previous valvuloplasty for mitral regurgitation. There were 27 men (55%) and 22 women, with a median age of 63 years (range 20 to 84 years). Original procedures included annuloplasty and posterior leaflet repair in 15 patients (31%), annuloplasty and anterior leaflet repair in 15 (31%), commissural plication in 13 (27%), and complex bileaflet repairs in six (12%). Median time between initial mitral repair and reoperation was 2.4 years (range 2 months to 25.3 years). Indications for reoperation included recurrent severe mitral regurgitation in 34 patients (70%), hemolytic anemia from mitral regurgitation in seven (14%), mixed mitral regurgitation and stenosis in seven (14%), and isolated mitral stenosis in one (2%). Before reoperation, 36 patients were in New York Heart Association functional class III and 11 were in class IV. Initial repairs were intact at the second operation in 32 patients (65%), and the etiology of recurrent mitral regurgitation in these patients was fibrosis or calcification of the anulus or leaflets in 22 patients, newly ruptured chordae in seven, and perforated leaflets in three. The causes of mitral regurgitation in the 17 patients whose initial repair had failed included dehiscence of commissural repairs in nine patients, dehiscence of ring annuloplasty in four, and break-down of chordal or leaflet repair in four. Patients with original repairs involving the anterior leaflet had a significantly shorter time between operations (p = 0.006). In eight patients (16%), the mitral valve was repaired again; in the remaining 41 patients (84%), prosthetic replacement was performed. Operative mortality rate was 4% (two patients). All eight patients who underwent mitral valve rerepair had no mitral regurgitation, trivial regurgitation, or mild regurgitation at discharge from the hospital. Follow-up was 100% complete at a mean of 5.1 years (range 1 to 19 years). Forty-one patients (87% were in New York Heart Association functional class I or II, and survival at 5 years was 75.3%. Of the eight patients who underwent a second repair, seven had no regurgitation, trivial regurgitation, or mild regurgitation at a median of 4 years' follow-up. The low mortality associated with reoperation supports an aggressive approach toward mitral regurgitation with initial repair. A second repair can be performed in selected patients with durable results at 4 years.

Extensive calcification of the mitral valve anulus: pathology and surgical management

Extensive calcification of the mitral valve anulus is a pathologic entity frequently associated with degenerative valvular disease. The calcification process remains localized to the anulus in 77% of the cases. It may extend, however, to the underlying myocardium. Whenever an operation is necessary for an associated valve insufficiency, the question arises whether it is preferable to repair or to replace the valve and how to manage the calcification. In the first part of this paper the pathology of this disease is studied, and in the discussion a mechanism is proposed to explain the development of the process of calcification. In the second part, a new operation is described, which comprises the temporary detachment of the leaflets, en bloc resection of the calcium deposit, annular reconstruction, and valve repair. For patients in whom the calcification extends to the myocardium a "sliding atrioplasty" of the left atrium is described, which allows the area of exposed muscular fibers to be covered. Between 1986 and 1994, among 68 patients with extensive calcification of the anulus and severe mitral valve insufficiency, 67 benefited from these repair techniques. Ages ranged from 18 to 82 years (mean 62 years). Thirty-two patients had a billowing mitral valve (Barlow), 27 a fibroelastic deficiency, and two Marfan's disease. The calcification involved more than one third of the anulus in 88% of the patients, the posterior anulus in 10.5%, and the whole anulus in 1.5%. The calcification process extended to the myocardial wall in 12% of the patients and to the papillary muscles in 4.5%. In the group of 67 valve repairs, there were two hospital deaths (2.9%), no instances of anulus dehiscence, and no early reoperations. The follow-up period extended from 4 months to 8 years (mean 3 years 8 months). There were two late deaths, 2 and 17 months after the operations, for an actuarial survival of 93% at 7 years. Late reoperation (6 to 62 months) was necessary in four patients (6.4%) for residual mitral valve incompetence (n=2), hemolysis (n=1), or endocarditis (n=1). In one of these patients a new repair was possible, whereas the three other patients required a valve replacement. All patients but one survived the reoperation. Actuarial freedom from reoperation was 87% at 7 years. All 60 patients with valve repair were reviewed for this study by clinical examination and echocardiography. All but one were in functional class I or II. There was no incompetence or trivial residual mitral valve incompetence in 55 patients and moderate incompetence in five. Two thromboembolic events have been recorded for a linearized rate of 1%/pt-yr. This study shows that complete anulus decalcification and valve repair can be done safely in patients with mitral valve insufficiency and extensive calcification of the anulus, even when the calcification process deeply involves the myocardium. It also demonstrates that an initially good result remained stable up to 7 years.

Repair of mitral regurgitation from myxomatous degeneration in the patient with a severely calcified posterior annulus

Severe posterior annular calcification poses a particular challenge to mitral valve repair. In a series of 252 mitral valve repairs for myxomatous degeneration performed between 1980 and 1993, 14 patients had a severely calcified posterior mitral valve annulus. Ages ranged from 61 to 81 years. Twelve patients were preoperative NYHA Class III or IV, and five patients required concurrent coronary artery bypass procedures. Operative techniques included complete resection of the calcified posterior annulus, resections of portions of the posterior leaflet with leaflet advancement, and placement of an annuloplasty ring. There were no operative deaths and all patients had a postoperative echocardiographic confirmation of relief from mitral regurgitation. During a mean follow-up time of 36 months (6 months to 8 years), there has been one late valve reoperation and only one late death, from thromboembolism in a patient with atrial fibrillation. These data indicate that even in the presence of severe calcification of the posterior mitral annulus, mitral valve repair for myxomatous degeneration can be performed with a low-operative risk and satisfactory long-term results.