Early and medium-term outcomes of Alfieri mitral valve repair in the management of systolic anterior motion during septal myectomy

Mitral Valve Interventions for Hypertrophic Obstructive Cardiomyopathy

The mitral valve (MV) plays an important role in the pathophysiology of hypertrophic obstructive cardiomyopathy (HOCM). Dynamic left ventricular outflow tract (LVOT) obstruction, caused by systolic anterior motion (SAM), is a common occurrence in most patients with hypertrophic cardiomyopathy and is directly associated with the MV apparatus. First line therapy for HOCM patients is pharmacological, and surgical intervention is often indicated for patients who do not respond to medical therapy. Emerging research on mitral disease in HOCM, specifically mitral regurgitation (MR), demonstrates that these patients frequently do not respond to standard therapeutic options, and can benefit from MV interventions. In this review, we describe the involvement of the MV in the pathogenesis of HOCM, discuss medical therapy, and explore available mitral procedures. Surgical myectomy, often combined with various modifications to the MV apparatus, is frequently necessary to achieve a durable resolution of LVOT obstruction and SAM-related MR. Alcohol septal ablation, an alternative to surgical myectomy, will be briefly mentioned. We also emphasize the role of transcatheter edge-to-edge repair (TEER) as a promising and novel therapeutic option for HOCM patients. Over time, TEER has established itself as an effective and safe procedure, demonstrating success across a spectrum of anatomical variations. The leaflet modification and movement restriction achieved through TEER help reduce SAM and, consequently, have the potential to alleviate LVOT obstruction and SAM-related MR. Furthermore, we propose a treatment algorithm for cases where TEER is a potential course of action for patients who are at high risk for other interventions.

Short time effects of two radiofrequency ablation methods on hypertrophic obstructive cardiomyopathy

BACKGROUND

Radiofrequency ablation has been applied for the treatment of hypertrophic obstructive cardiomyopathy (HOCM). The two known procedures are percutaneous intramyocardial septal radiofrequency ablation (PIMSRA) and endocardial radiofrequency septal ablation (ERSA).

METHODS

This study presents a retrospective analysis of the PIMSRA and ERSA procedures in patients with drug-refractory HOCM. A total of 28 patients participated in the study, with 12 receiving PIMSRA and 16 receiving ERSA. The objective of our study was to compare the short-term effects of these two radiofrequency ablation procedures.

RESULTS

At the 30-day follow-up, the PIMSRA group demonstrated a greater reduction in left ventricular outflow tract peak gradient at rest compared to the ERSA group (22.25 [16.72] mmHg versus 47.75 [21.94] mmHg) (p < .01). The values for the PIMSRA group decreased from 99.33 (32.00) mmHg to 22.25 (16.72) mmHg (p < .01), while the ERSA group decreased from 97.75 (30.24) mmHg to 47.75 (21.94) mmHg (p < .01). Only the PIMSRA group exhibited a decrease in mitral regurgitation (MR). The area of MR decreased from 10.13 (4.12) mm2 to 3.65 (2.80) mm2 in the PIMSRA group (p < .01). Additionally, the PIMSRA group experienced reductions in left atrial diameter (LAD) and left ventricular ejection fraction (LVEF)%. The values for LAD changed from 43.58 (7.53) mm to 37.08 (6.92) mm (p = .03), and the values for LVEF% decreased from 65.75 (6.12) pg/mL to 60.83 (4.06) pg/mL (p = .03).

CONCLUSION

In terms of the two types of radiofrequency ablation methods used in HOCM, it has been observed that PIMSRA demonstrates a more favorable early treatment effect compared to ERSA.

Adding Surgical Edge-to-Edge Mitral Valve Repair to Myectomy in Hypertrophic Obstructive Cardiomyopathy: Long-Term Functional and Echocardiographic Outcome

This study evaluates the early and long-term clinical and echocardiographic outcome of edge-to-edge (E2E) mitral valve repair (MVr) concomitant to septal myectomy (SM) in patients with symptomatic hypertrophic obstructive cardiomyopathy (HOCM). A retrospective single-center analysis was performed of patients who underwent isolated SM or SM with E2E MVr from 2011 to 2022. Exclusion criteria were primary mitral valve (MV) disease or concomitant valve surgery. Early and long-term safety, functional and echocardiographic outcomes were compared between groups. Between January 2011 and April 2022, 76 consecutive patients underwent SM for HOCM: 42 patients (55%) underwent SM without additional E2E MVr (Group 1) and 34 patients (45%) underwent SM with additional E2E MVr (Group 2). At latest follow-up, 87% of patients were in New York Heart Association (NYHA) class I-II with no significant differences in NYHA class between groups. Incidence of safety events was comparable between groups. Echocardiographic relief of left ventricular outflow tract (LVOT) obstruction was comparable at early follow-up (P = 0.68), with a significant but small difference in maximum LVOT pressure gradient at latest follow-up in favor of E2E MVr (P = 0.04). Furthermore, patients who underwent SM with E2E MVr showed less residual systolic anterior motion at early and latest follow-up (P = 0.020; P = 0.178). Reintervention on the MV was absent in both groups at 1 year and equally low at follow-up (P = 0.27). This study demonstrates that adding E2E MVr to septal myectomy is as safe as isolated myectomy for the treatment of HOCM. Moreover, the addition of E2E MVr is associated with similar excellent functional improvement and freedom from MV reintervention.

Review of Contemporary Invasive Treatment Approaches and Critical Appraisal of Guidelines on Hypertrophic Obstructive Cardiomyopathy: State-of-the-Art Review

BACKGROUND

Hypertrophic obstructive cardiomyopathy (HOCM) is a heterogeneous disease with different clinical presentations, albeit producing similar dismal long-term outcomes if left untreated. Several approaches are available for the treatment of HOCM; e.g., alcohol septal ablation (ASA) and surgical myectomy (SM). The objectives of the current review were to (1) discuss the place of the standard invasive treatment modalities (ASA and SM) for HOCM; (2) summarize and compare novel techniques for the management of HOCM; (3) analyze current guidelines addressing HOCM management; and (4) offer suggestions for the treatment of complex HOCM presentations.

METHODS

We searched the literature and attempted to gather the most relevant and impactful available evidence on ASA, SM, and other invasive means of treatment of HOCM. The literature search yielded thousands of results, and 103 significant publications were ultimately included.

RESULTS

We critically analyzed available guidelines and provided context in the setting of patient selection for standard and novel treatment modalities. This review offers the most comprehensive analysis to-date of available invasive treatments for HOCM. These include the standard treatments, SM and ASA, as well as novel treatments such as dual-chamber pacing and radiofrequency catheter ablation. We also account for complex pathoanatomic presentations and current guidelines to offer suggestions for tailored care of patients with HOCM. Finally, we consider promising future therapies for HOCM.

CONCLUSIONS

HOCM is a heterogeneous disease associated with poor outcomes if left untreated. Several strategies for treatment of HOCM are available but patient selection for the procedure is crucial.

Resurgence of the edge-to-edge repair of the mitral valve

PURPOSE OF REVIEW

To provide a critical review of the application and outcomes of surgical edge-to-edge (E2E) or Alfieri repair for mitral valvulopathy.

RECENT FINDINGS

The E2E repair is a surgical technique to address mitral regurgitation, particularly suited when the responsible mechanism is bileaflet prolapse combined with enlarged annular area. It can also be used for a range of mitral valve pathologies. Surgically, the technique has been employed as a bailout for unsuccessful repair including residual mitral regurgitation because of systolic anterior motion (SAM). E2E repair should be accompanied by a ring annuloplasty for long-term repair durability. The simplicity of this approach makes it an ideal strategy during minimally-invasive mitral valve repair. It may also be performed via a transaortic approach at the time of aortic valve surgery to address less-than-severe mitral regurgitation or to address residual SAM following myectomy for hypertrophic obstructive cardiomyopathy. We review the surgical indication, potential complications including risk of mitral stenosis and the long-term outcomes of E2E repair.

SUMMARY

The E2E surgical repair is a simple and effective surgical strategy to address a wide range of mitral regurgitation. This is an important technique in the surgical armamentarium especially in cases of minimally-invasive mitral valve surgery.

Trapezoidal resection of an elongated anterior mitral leaflet and Alfieri stitch in hypertrophic cardiomyopathy

Background

In individuals with hypertrophic obstructive cardiomyopathy, elongated anterior mitral leaflets are commonly associated with systolic anterior motion. In patients with mild septal hypertrophy, a myectomy is considered insufficient to relieve systolic anterior motion and left ventricular outflow tract obstruction.

Case presentation

In the patient, who had relatively mild septal hypertrophy, the section of the anterior leaflet protruding into the left ventricular outflow tract was resected, concomitant with septal myectomy and the relocation of the papillary muscles. An edge-to-edge stitch was placed at the uppermost segment of the coaptation zone. Using these manoeuvres, systolic anterior motion, left ventricular outflow tract obstruction and mitral regurgitation were successfully resolved postoperatively.

Conclusions

We describe a surgical technique with an edge-to-edge suture for the resection of an elongated anterior mitral leaflet. In combination with septal myectomy and relocation of the papillary muscles, this technique is a simple and viable option, especially when septal hypertrophy is not severe.

Individualized surgical strategies for left ventricular outflow tract obstruction in hypertrophic cardiomyopathy

OBJECTIVES

Surgical strategies to treat drug refractory left ventricular outflow tract obstruction (LVOTO) in hypertrophic cardiomyopathy include septal myectomy (SM) and, less frequently, mitral valve (MV) repair or replacement. The primary aim of this study was to report the surgical technique and management outcomes in a consecutive group of patients with variable phenotypes of hypertrophic cardiomyopathy in a broad national specialist practice.

METHODS

A total of 203 consecutive patients, 132 men (mean age 48.6 ± 14.6 years) underwent surgery for the management of LVOTO. Surgical approaches included SM (n = 159), SM with MV repair (n = 25), SM with MV replacement (n = 9) and MV replacement alone (n = 10). Specific surgical approaches were performed based on the underlying mechanism of obstruction. Eleven (5.4%) patients had previous alcohol septal ablation for the management of LVOTO. Concomitant non-mitral cardiac procedures were carried out in 22 (10.8%) patients.

RESULTS

Operative survival rate was 99.0% with 2 deaths within 30 days. The mean bypass time was 92.9 ± 47.8 min, with a mean length of hospital stay of 10.5 ± 7.8 days. Surgical complications included 3 ventricular septal defects requiring repair (1.5%), 1 Gerbode defect surgically repaired, 2 aortic valve repairs (1.0%), 2 transient ischaemic attacks (1.0%) and 4 strokes (2.0%). Thirty-nine (19.2%) patients had perioperative new-onset atrial fibrillation and 8 (3.9%) patients had unexpected atrioventricular block requiring a permanent pacemaker. Mean resting left ventricular outflow tract gradient improved from 70.6 ± 40.3 mmHg preoperatively to 11.0 ± 10.5 mmHg at 1 year postoperatively (P < 0.001). Mean New York Heart Association class improved from 2.6 ± 0.5 preoperatively to 1.6 ± 0.6 at 1 year after the procedure.

CONCLUSIONS

In variable phenotypes of LVOTO in hypertrophic cardiomyopathy, an individualized surgical approach provided effective reductions in left ventricular outflow tract gradients and good symptomatic relief with acceptable mortality and morbidity.