Mid-term clinical outcomes of totally endoscopic repair for mitral regurgitation in Barlow's disease.

OBJECTIVE: This study aimed to confirm the safety and feasibility of totally endoscopic repair for mitral regurgitation (MR) in Barlow's disease. METHODS: From June 2018 to December 2022, 21 consecutive Barlow's disease patients (aged 33 ± 12 years; 57.1% male) underwent totally endoscopic mitral valve (MV) repair with leaflets folding, multiple artificial chordae implantation and ring annuloplasty. The safety and feasibility of this technique was evaluated by its mid-term clinical outcomes. RESULTS: There was no operative death or complications. The mean cardiopulmonary bypass (CPB) time was 190 ± 41 (128-267) min, and the aortic cross-clamp time was 145 ± 32 (66-200) min. The average number of artificial chordae implantation was 2.9 ± 0.7 (1-4) pairs. The mean MV coaptation length was 1.4 ± 0.3 (0.8-1.8) cm, and the median transvalvular gradient was 1 [interquartile range (IQR), 1-2] mmHg. During a median follow-up time of 24 (IQR, 10-38) months, all patients showed persistent effective valve function with no significant MR or systolic anterior motion. CONCLUSIONS: Totally endoscopic repair was a safe, effective, and reproducible procedure with satisfied mid-term clinical outcomes for MR in Barlow's disease. However, further randomized and long-term follow-up studies were warranted to determine its clinical effects.

Large Animal Translational Validation of 3 Mitral Valve Repair Operations for Mitral Regurgitation Using a Mitral Valve Prolapse Model: A Comprehensive In Vivo Biomechanical Engineering Analysis.

BACKGROUND: Various mitral repair techniques have been described. Though these repair techniques can be highly effective when performed correctly in suitable patients, limited quantitative biomechanical data are available. Validation and thorough biomechanical evaluation of these repair techniques from translational large animal in vivo studies in a standardized, translatable fashion are lacking. We sought to evaluate and validate biomechanical differences among different mitral repair techniques and further optimize repair operations using a large animal mitral valve prolapse model. METHODS: Male Dorset sheep (n=20) had P2 chordae severed to create the mitral valve prolapse model. Fiber Bragg grating force sensors were implanted to measure chordal forces. Ten sheep underwent 3 randomized, paired mitral valve repair operations: neochord repair, nonresectional leaflet remodeling, and triangular resection. The other 10 sheep underwent neochord repair with 2, 4, and 6 neochordae. Data were collected at baseline, mitral valve prolapse, and after each repair. RESULTS: All mitral repair techniques successfully eliminated regurgitation. Compared with mitral valve prolapse (0.54±0.18 N), repair using neochord (0.37±0.20 N; P=0.02) and remodeling techniques (0.30±0.15 N; P=0.001) reduced secondary chordae peak force. Neochord repair further decreased primary chordae peak force (0.21±0.14 N) to baseline levels (0.20±0.17 N; P=0.83), and was associated with lower primary chordae peak force compared with the remodeling (0.34±0.18 N; P=0.02) and triangular resectional techniques (0.36±0.27 N; P=0.03). Specifically, repair using 2 neochordae resulted in higher peak primary chordal forces (0.28±0.21 N) compared with those using 4 (0.22±0.16 N; P=0.02) or 6 neochordae (0.19±0.16 N; P=0.002). No difference in peak primary chordal forces was observed between 4 and 6 neochordae (P=0.05). Peak forces on the neochordae were the lowest using 6 neochordae (0.09±0.11 N) compared with those of 4 neochordae (0.15±0.14 N; P=0.01) and 2 neochordae (0.29±0.18 N; P=0.001). CONCLUSIONS: Significant biomechanical differences were observed underlying different mitral repair techniques in a translational large animal model. Neochord repair was associated with the lowest primary chordae peak force compared to the remodeling and triangular resectional techniques. Additionally, neochord repair using at least 4 neochordae was associated with lower chordal forces on the primary chordae and the neochordae. This study provided key insights about mitral valve repair optimization and may further improve repair durability.

Mitral valve repair for degenerative mitral regurgitation with Carpentier's functional classification type II in elderly patients: a single center experience.

OBJECTIVE: Mitral valve (MV) repair for Carpentier functional classification Type II (C-II) mitral regurgitation (MR) is widely accepted because of its efficacy. It is unclear whether MV repair has the same benefits in elderly patients as in younger patients because of their lower life expectancy. Herein, we examined the midterm results of MV repair for C-II mitral regurgitation, especially in patients aged ≧70 years. METHOD: A retrospective review was performed on 176 patients who underwent MV repair for C-II mitral regurgitation with a median age of 65 years; 55 (31%) patients were ≧70 years, and 124 were male (71%). Lesions of the mitral valve were isolated from the anterior leaflet (48 patients), posterior leaflet (113 patients), and both leaflets (15 patients), and included seven patients with Barlow's disease. We compared the outcomes between patients aged ≧70 years (≧70 years; median age, 76 years) and those aged < 70 years (median age, 60 years). RESULTS: In terms of the durability of MV repair in elderly patients, there were no significant differences in the rates of freedom from reoperation or MR recurrence at 5 years between patients aged < 70 years and those aged ≧70 years (reoperation:98% in < 70 years versus 89% in ≧70 years; P = 0.4053; MR recurrence:95% in < 70 years versus 81% in ≧70 years; P = 0.095). The mitral valve complexity was divided into two grades: Simple (isolated posterior mitral lesion) and Complex (isolated anterior lesion or both lesions). In patients aged < 70 years, there was no significant difference in the rate of freedom from MR recurrence at 5 years between the Simple and Complex groups (96% vs. 91%; P = 0.1029). In contrast, in patients aged ≧70 years, the MR recurrence rate at 3 years in Complex was significantly higher in the Complex group than in the Simple (100% vs. 80%; P = 0.0265). CONCLUSIONS: We studied the outcomes of MV repair for C-II in MR. In elderly patients, MR recurrence was higher in complex lesions than in simple lesions. MV replacement may be considered for elderly patients with complex mitral valve lesions, if appropriately selected.

Biomechanical engineering analysis of neochordae length's impact on chordal forces in mitral repair.

OBJECTIVES: Artificial neochordae implantation is commonly used for mitral valve (MV) repair. However, neochordae length estimation can be difficult to perform. The objective was to assess the impact of neochordae length changes on MV haemodynamics and neochordal forces. METHODS: Porcine MVs (n = 6) were implanted in an ex vivo left heart simulator. MV prolapse (MVP) was generated by excising at least 2 native primary chordae supporting the P2 segments from each papillary muscle. Two neochordae anchored on each papillary muscle were placed with 1 tied to the native chord length (exact length) and the other tied with variable lengths from 2× to 0.5× of the native length (variable length). Haemodynamics, neochordal forces and echocardiography data were collected. RESULTS: Neochord implantation repair successfully eliminated mitral regurgitation with repaired regurgitant fractions of approximately 4% regardless of neochord length (P < 0.01). Leaflet coaptation height also significantly improved to a minimum height of 1.3 cm compared with that of MVP (0.9 ± 0.4 cm, P < 0.05). Peak and average forces on exact length neochordae increased as variable length neochordae lengths increased. Peak and average forces on the variable length neochordae increased with shortened lengths. Overall, chordal forces appeared to vary more drastically in variable length neochordae compared with exact length neochordae. CONCLUSIONS: MV regurgitation was eliminated with neochordal repair, regardless of the neochord length. However, chordal forces varied significantly with different neochord lengths, with a preferentially greater impact on the variable length neochord. Further validation studies may be performed before translating to clinical practices.

Feasibility of concomitant exclusion of left atrial appendage during novel transapical off-pump beating heart mitral valve repair.

The AtriClip device enables the safe and reproducible epicardial clipping of the left atrial appendage. Transapical off-pump beating heart mitral valve repair using NeoChord DS100 Artificial Chordae Delivery System has matured and become more standardized. We aim to evaluate the feasibility of combining NeoChord repair and left atrial appendage exclusion in a single procedure through the same minithoracotomy in patients with mitral valve prolapse and atrial fibrillation. From 2018 to 2019, seven patients with severe mitral regurgitation and atrial fibrillation underwent transesophageal echocardiography-guided transapical off-pump mitral valve repair with the novel NeoChord DS 1000 system and concomitant left atrial appendage exclusion using the AtriClip Pro II device. Both procedures were performed via left mini-thoracotomy. The AtriClip device was applied after the NeoChord repair was done. All seven patients had less than moderate mitral regurgitation after the NeoChord repair and successful left atrial appendage occlusion. There were no device or procedure-related complications. Clinical follow-up revealed significant symptomatic improvement, and no cardiovascular complications were reported. Transesophageal echocardiography at 6-12 months post-procedure showed stable left atrial appendage occlusion with no residual flow between the left atrium and the left atrial appendage and a stump of less than 5 mm. Beating heart epicardial clipping of the left atrial appendage using AtriClip concomitant with transapical mitral valve repair using Neochord DS 1000 system is a feasible and safe treatment option in mitral valve prolapse and atrial fibrillation in patients with limited indications. However, its safety needs to be confirmed in a larger series of patients.

Left ventricular fibrosis and CMR tissue characterization of papillary muscles in mitral valve prolapse patients.

PURPOSE: Mitral valve prolapse (MVP) is associated with left ventricle (LV) fibrosis, including the papillary muscles (PM), which is in turn linked to malignant arrhythmias. This study aims to evaluate comprehensive tissue characterization of the PM by cardiovascular magnetic resonance (CMR) imaging and its association with LV fibrosis observed by intraoperative biopsies. METHODS: MVP patients with indication for surgery due to severe mitral regurgitation (n = 19) underwent a preoperative CMR with characterization of the PM: dark-appearance on cine, T1 mapping, conventional bright blood (BB) and dark blood (DB) late gadolinium enhancement (LGE). CMR T1 mapping was performed on 21 healthy volunteers as controls. LV inferobasal myocardial biopsies were obtained in MVP patients and compared to CMR findings. RESULTS: MVP patients (54 ± 10 years old, 14 male) had a dark-appearance of the PM with higher native T1 and extracellular volume (ECV) values compared with healthy volunteers (1096 ± 78ms vs. 994 ± 54ms and 33.9 ± 5.6% vs. 25.9 ± 3.1%, respectively, p < 0.001). Seventeen MVP patients (89.5%) had fibrosis by biopsy. BB-LGE + in LV and PM was identified in 5 (26.3%) patients, while DB-LGE + was observed in LV in 9 (47.4%) and in PM in 15 (78.9%) patients. DB-LGE + in PM was the only technique that showed no difference with detection of LV fibrosis by biopsy. Posteromedial PM was more frequently affected than the anterolateral (73.7% vs. 36.8%, p = 0.039) and correlated with biopsy-proven LV fibrosis (Rho 0.529, p = 0.029). CONCLUSIONS: CMR imaging in MVP patients referred for surgery shows a dark-appearance of the PM with higher T1 and ECV values compared with healthy volunteers. The presence of a positive DB-LGE at the posteromedial PM by CMR may serve as a better predictor of biopsy-proven LV inferobasal fibrosis than conventional CMR techniques.

Considerations & challenges of mitral valve repair in females: diagnosis, pathology, and intervention.

PURPOSE OF REVIEW: Disparities in mitral valve (MV) repair outcomes exist between men and women. This review highlights sex-specific differences in MV disease aetiology, diagnosis, as well as timing and type of intervention. RECENT FINDINGS: Females present with more complicated disease: anterior or bileaflet prolapse, leaflet dysplasia/thickening, mitral annular calcification, and mixed mitral lesions. The absence of indexed echocardiographic mitral regurgitation (MR) severity parameters contributes to delayed intervention in women, resulting in more severe symptom burden at time of surgery. The sequelae of chronic MR also necessitate concomitant procedures (e.g. tricuspid repair, arrhythmia surgery) at the time of mitral surgery. Complex MV pathology, greater patient acuity, and more complicated procedures collectively pose challenges to successful MV repair and postoperative recovery. As a consequence, women receive disproportionately more MV replacement than men. In-hospital mortality after MV repair is also greater in women than men. Long-term outcomes of MV repair are comparable after risk-adjustment for preoperative status; however, women experience a greater incidence of postoperative heart failure. SUMMARY: To address the inequity in MV repair outcomes between sexes, indexed diagnostic measurements, diligent surveillance of asymptomatic MR, increased recruitment of women in large clinical trials, and mandatory reporting of sex-based subgroup analyses are recommended.

Effects of Mitral Valve Surgery on Ventricular Arrhythmia in Mitral Valve Prolapse Patients: Five-Year Eollow-up.

Aim      To evaluate the effect of mitral valve (MV) repair and replacement on the incidence of ventricular arrhythmias (VA) and to identify risk factors for the persistence of VA in patients with MV prolapse and severe mitral regurgitation (MR) during a mid-term follow-up.Material and methods  A single-site observational, prospective study successively enrolled 30 patients (mean age, 55.2±9.9 years, 60% men) who underwent MV repair or replacement for severe MR due to MV prolapse or chordal avulsion. Transthoracic echocardiography and Holter monitoring were performed in all patients before and annually after surgery. A pathomorphological study of MV fragments excised during surgery was performed.Results During the five-year follow-up period (144 person-years), one case of sudden cardiac death outside a health care facility was recorded. MR severity progressed in three patients after MV repair. The total number of all VAs decreased during the follow-up period, with a significant decrease in the number of paroxysms of unstable ventricular tachycardia during the first two years after surgery. The presence of VA in the postoperative period was correlated with the severity of postoperative left ventricular (LV) remodeling: end-diastolic volume (EDV) (rs=0.69; p=0.005), LV ejection fraction (EF) (rs = -0.55; p=0.004) and severity of MV myxomatous alterations according to histological study data (rτ=0.58; p=0.045). The beta-blocker treatment did not influence the VA frequency and severity (rs= -0.18; p=0.69). According to a univariate regression analysis only EDV (p = 0.001), LVEF <50% (p = 0.003), and myxomatous MV degeneration (p = 0.02) were risk factors for persistent ventricular tachycardia in the postoperative period.Conclusion      Surgical intervention on MV in patients with MV prolapse and severe MR decreased the number of cases of malignant VAs and was correlated with the postoperative changes in LV volume and function, as well as the severity of MV myxomatous alterations.

Midterm Results of Mitral Valve Repair Using Loop Technique With Simple Height Reduction of the Large Posterior Leaflet.

OBJECTIVE: Systolic anterior motion (SAM) is one of the most serious problems in mitral valve repair. Height reduction is a key procedure to solve SAM, and there are limited data on the surgical results of height reduction procedure. This study is to assess the effectiveness and midterm results of simple height reduction procedure for SAM in patients with severe mitral regurgitation (MR). METHODS: From 2008 to 2022, 50 patients underwent loop technique with an additional simple height reduction procedure for prevention of SAM. We examined the midterm results of patients with simple height reduction regarding recurrent MR and reoperation. The follow-up period ranged from 171 to 3,816 days (median, 883 days). RESULTS: There were 338 patients (87%) who underwent loop technique without height reduction and 50 patients (13%) who underwent loop technique with height reduction. After the height reduction procedure, SAM was prevented in 44 patients, and 6 patients needed volume loading to suppress SAM. Freedom from recurrence of moderate to severe or severe MR at 1, 3, and 5 years was 98%, 88%, and 88% in the height reduction group versus 98%, 96%, and 94% in the group with loop technique alone (P = 0.074). Receiver operating characteristic curves showed that a systolic dimension of 26 mm had a sensitivity of 75% and a specificity of 83% for predicting SAM after height reduction. CONCLUSIONS: Loop technique with simple height reduction was a simple, secure, and effective procedure to prevent SAM and recurrent significant MR in the midterm periods.

Mitral Valve Prolapse in Obstructive Hypertrophic Cardiomyopathy.

Obstructive hypertrophic cardiomyopathy (oHCM) and mitral valve (MV) prolapse (MVP) are the 2 conditions which could cause symptomatic heart failure and sudden cardiac death. The clinical characteristics and surgical outcomes of patients with oHCM and MVP have not been well reported. From April 2012 to February 2018, 84 patients with oHCM (28 patients with MVP and 56 gender- and age-matched patients without MVP) who underwent septal myectomy at our institution were enrolled in this study. Information on clinical characteristics and outcomes was obtained from electronic medical records and follow-up surveys. Compared with those without MVP, patients with MVP were more symptomatic (New York Heart Association class III to IV; 96% vs 77%), more often moderate-to-severe mitral regurgitation (86% vs 48%), atrial fibrillation (39% vs 11%) and higher incidence of nonsustained ventricular tachycardia (44% vs 15%). Twenty (71%) had MV repair and 8 (29%) had MV replacement. Compared with patients without MVP, those with MVP had a longer postoperative hospital stay (10.9 ± 6.4 vs 7.8 ± 2.8 days). None of the 84 study patients died during hospital or follow-up. At the most recent echocardiographic evaluation, left ventricular outflow tract gradient significantly decreased from 69.7 ± 35.4 millimeters of mercury to 7.3 ± 5.1 millimeters of mercury and the degree of mitral valve regurgitation improved from grade 2.43 ± 0.69 to grade 0.5 ± 0.69. In conclusion, MVP occurs rarely in oHCM, and was related to atrial fibrillation, ventricular arrhythmia and mitral regurgitation. Mitral valve surgery in combination with myectomy is effective and safe for patients with oHCM and MVP, relieving substantially left ventricular outflow tract gradients and mitral regurgitation.

Echocardiographic diagnosis of rupture of mitral valve papillary muscle.

OBJECTIVE: To explore the value of echocardiography in diagnosing papillary muscle rupture (PMR) of the mitral valve, and summarize the characteristic echocardiographic features of different types. METHODS: Echocardiograms of 13 PMR patients confirmed by surgery in Wuhan Union Hospital between January 2009 and December 2022 were retrospectively analyzed and their preoperative transthoracic echocardiography (TTE) was compared with surgical findings. RESULTS: A total of 9020 patients underwent mitral valve repair or replacement surgery during the study period including 13 (0.14%) for PMR. Of the 13 PMRs, 8 cases were partial PMR(P-PMR), 5 cases were complete PMR(C-PMR); 3 cases were anterolateral PMR, and 10 were posteromedial PMR. The diagnostic accuracy, sensitivity, and specificity of the preoperative TTE were 99.9%, 53.8% and 99.9% respectively. Echocardiographic features of 10 patients (5-C-PMR and 5 P-PMR) with detailed TTE and intraoperative transesophageal echocardiography (TEE) data included: both anterior and posterior leaflets prolapse (C-PMR 60% vs P-PMR 60%); flail leaflet (C-PMR100% vs P-PMR 40%); All C-PMRs and P-PMRs have severe, eccentric and lateral regurgitation; flail attachment (chordae tendinae and ruptured PM) at the tip of prolapsed leaflet (C-PMR100% vs P-PMR 60%); high-echo masses resembled "champagne glasses" in 100% of the C-PMR; high-echo masses resembled "lotus-seedpod" in 60% and "dumbbell-shaped" torn PM in remaining 40% of the P-PMR. CONCLUSIONS: Different PMR subtypes have different echocardiographic characteristics. Combining TTE and TEE can accurately identify the typical features of PMR such as ipsilateral hemipetal leaflet prolapse, high-echoic mass at the tip of the leaflet, massive eccentricity and lateral regurgitation.

Three-Dimensional Finger Test: A New Echocardiographic Method to Locate the Best Access Site During NeoChord Procedure.

OBJECTIVE: Transventricular beating-heart mitral valve repair (TBMVR) with artificial chordae implantation is a technique to treat mitral valve prolapse. Two-dimensional (2D) echocardiography completed with simultaneous biplane view during surgeon finger pushing on the left ventricular (LV) wall (finger test [FT]) is currently used to localize the desired LV access, on the inferior-lateral wall, between the papillary muscles (PMs). We aimed to compare a new three-dimensional (3D) method with conventional FT in terms of safety and better localization of LV access. METHODS: During TBMVR, conventional FT was completed using 3D transesophageal echocardiography by placing the sample box in the bicommissural view of the LV, including the PMs and the apex. The 3D volume was subsequently edited to visualize the LV from above (surgical view) to localize the bulge of the operator's finger pushing on the LV. We asked the first operator, the second operator, and the cardiac surgery fellow, separately, to evaluate the location of their finger pushing, both with the 2D method and the 3D method, to estimate the interoperator concordance. RESULTS: From 2019 to 2021, 42 TBMVRs were performed without complications related to access using FT completed with the 3D method. Regarding the choice of the right and safe entry site, the operator's agreement was higher using 3D rendering compared with conventional FT (mean agreement 0.59 ± 0.29 for 2D vs 0.83 ± 0.20 for 3D), while full operator agreement was 10 of 42 for 2D and 23 of 42 for 3D (P = 0.004). CONCLUSIONS: Three-dimensional FT is easy to perform and facilitates surgeons choosing the best access for TBMVR in term of anatomical localization and safety.

Neochordae implantation versus leaflet resection in mitral valve posterior leaflet prolapse and dilated left ventricle: a propensity score matching comparison with long-term follow-up.

OBJECTIVES: Uncorrected severe mitral regurgitation (MR) due to posterior prolapse leads to left ventricular dilatation. At this stage, mitral valve repair becomes mandatory to avoid permanent myocardial injury. However, which technique among neochoardae implantation and leaflet resection provides the best results in this scenario remains unknown. METHODS: We selected 332 patients with left ventricular dilatation and severe degenerative MR due to posterior leaflet (PL) prolapse who underwent neochoardae implantation (85 patients) or PL resection (247 patients) at our institution between 2008 and 2020. A propensity score matching analysis was carried on to decrease the differences at baseline. RESULTS: Matching yielded 85 neochordae implantations and 85 PL resections. At 10 years, freedom from cardiac death and freedom from mitral valve reoperation were 92.6 ± 6.1% vs 97.8 ± 2.1% and 97.7 ± 2.2% vs 95 ± 3% in the neochordae group and in the PL resection group, respectively. The MR ≥2+ recurrence rate was 23.9 ± 10% in the neochordae group and 20.8 ± 5.8% in the PL resection group (P = 0.834) at 10 years. At the last follow-up, the neochordae group showed a higher reduction of left ventricular end-diastolic diameter (44 vs 48 mm; P = 0.001) and a better ejection fraction (60% vs 55%; P < 0.001) compared to PL resection group. CONCLUSIONS: In this subgroup of patients, both neochordae implantation and leaflet resection provide excellent durability of the repair in the long term. Neochordae implantation might have a better effect on dilated left ventricle.

Acute mitral regurgitation with and without acute heart failure.

Acute severe mitral regurgitation (MR) is rare, but often leads to cardiogenic shock, pulmonary edema, or both. Most common causes of acute severe MR are chordae tendineae (CT) rupture, papillary muscle (PM) rupture, and infective endocarditis (IE). Mild to moderate MR is often seen in patients with acute myocardial infarction (AMI). CT rupture in patients with floppy mitral valve/mitral valve prolapse is the most common etiology of acute severe MR today. In IE, native or prosthetic valve damage can occur (leaflet perforation, ring detachment, other), as well as CT or PM rupture. Since the introduction of percutaneous revascularization in AMI, the incidence of PM rupture has substantially declined. In acute severe MR, the hemodynamic effects of the large regurgitant volume into the left atrium (LA) during left ventricular (LV) systole, and in turn back into the LV during diastole, are profound as the LV and LA have not had time to adapt to this additional volume. A rapid, but comprehensive evaluation of the patient with acute severe MR is essential in order to define the underline cause and apply appropriate management. Echocardiography with Doppler provides vital information related to the underlying pathology. Coronary arteriography should be performed in patients with an AMI to define coronary anatomy and need for revascularization. In acute severe MR, medical therapy should be used to stabilize the patient before intervention (surgery, transcatheter); mechanical support is often required. Diagnostic and therapeutic steps should be individualized, and a multi-disciplinary team approach should be utilized.

Off-Pump Neochordae Implantation via Left Minithoracotomy for Recurrent Regurgitation Following Mitral Valve Repair: The First Case in Japan.

Surgical fixation after recurrent regurgitation following surgical mitral repair has been technically demanding and associated with high morbidity and mortality. Avoiding reopening the adhesive site or limiting the usage of cardiopulmonary bypass are solutions for reducing the operative risk. We report a case of recurrent mitral regurgitation treated by off-pump neochordae implantation via left minithoracotomy. A 69-year-old woman with a history of conventional mitral repair via median sternotomy developed heart failure due to mitral regurgitation from recurrent posterior leaflet P2 prolapse. Four neochordaes were implanted off-pump via left minithoracotomy using a NeoChord DS1000 in the seventh intercostal space. No transfusion was required. The patient was discharged a week after the procedure with no complications. The regurgitation remains trivial 6 months after the NeoChord procedure.

Repair of mitral prolapse: comparison of thoracoscopic minimally invasive and conventional approaches.

OBJECTIVES: Surgical repair remains the best treatment for severe primary mitral regurgitation (MR). Minimally invasive mitral valve surgery is being increasingly performed, but there is a lack of solid evidence comparing thoracoscopic with conventional surgery. Our objective was to compare outcomes of both approaches for repair of leaflet prolapse. METHODS: All consecutive patients undergoing surgery for severe MR due to mitral prolapse from 2012 to 2020 were evaluated according to the approach used. Freedom from mortality, reoperation and recurrent severe MR were evaluated by Kaplan-Meier method. Differences in baseline characteristics were adjusted with propensity score-matched analysis (1:1, nearest neighbour). RESULTS: Three hundred patients met inclusion criteria and were divided into thoracoscopic (N = 188) and conventional (sternotomy; N = 112) groups. Unmatched patients in the thoracoscopic group were younger and had lower body mass index, New York Heart Association class and EuroSCORE II preoperatively. After matching, thoracoscopic group presented significantly shorter mechanical ventilation (9 vs 15 h), shorter intensive care unit stay (41 vs 65 h) and higher postoperative haemoglobin levels (11 vs 10.2 mg/dl) despite longer bypass and cross-clamp times (+30 and +17 min). There were no differences in mortality or MR grade at discharge between groups nor differences in survival, repair failures and reinterventions during follow-up. CONCLUSIONS: Minimally invasive mitral repair can be performed in the majority of patients with mitral prolapse, without compromising outcomes, repair rate or durability, while providing shorter mechanical ventilation and intensive care unit stay and less blood loss.