Transmitral Myectomy Research Articles

Longitudinal valvotomy of anterior leaflet for endoscopic transmitral myectomy for hypertrophic obstructive cardiomyopathy.

Transmitral myectomy for hypertrophic obstructive cardiomyopathy is compatible with minimally invasive surgery compared with traditional transaortic access. It has often been performed in conjunction with mitral valve replacement or temporary detachment of the anterior leaflet from its annulus. We present a novel approach: longitudinal incision at the midline of the anterior mitral leaflet for septal myectomy. The procedure is ideally conducted endoscopically or robotically through the right chest. Cardiopulmonary bypass is established in the usual manner. After cardioplegic arrest, the mitral valve is exposed, and the anterior mitral leaflet is incised longitudinally at the midline. Both parts of the leaflet are tentatively fixed to the atrial wall with sutures to keep them open. Using the look-up mode of a 30° scope, the right cusp of the aortic valve is observed. Myectomy is initiated close to the aortic annulus using the pure-cut mode of electrocautery and scissors, then extended apically as necessary. After myectomy, the anterior leaflet is reapproximated with interrupted sutures. This technique is simpler than the detachment of the anterior leaflet and does not require patch materials that could lead to durability issues for the reconstruction of the anterior leaflet.

Innovation in surgical treatment of hypertrophic obstructive cardiomyopathy in children.

Hypertrophic cardiomyopathy is the second most common cardiomyopathy affecting children and adolescents and is the main cause of sudden death of young athletes. The natural prognosis of children with severe hypertrophic obstructive cardiomyopathy is not optimistic, and it is not uncommon for children with hypertrophic obstructive cardiomyopathy who do not respond to medication. Surgical treatment is often the only solution. Conventional surgical methods in the past include classic or modified extended Morrow operation, classic or modified Konno operation, and Ross-Konno operation. In recent years, with the development of minimally invasive surgery, various minimally invasive surgical methods have emerged endlessly. Because the incision of minimally invasive cardiac surgery is significantly smaller than that of traditional surgery, it causes less trauma, recovers quickly after surgery, and has the advantage of no difference in surgical effect compared with traditional median sternotomy. Tally endoscopic transmitral myectomy, RTM, minimally right thoracotomy, and other surgical methods have achieved encouraging results in adults and some older children with hypertrophic obstructive cardiomyopathy. The appearance of transapical beating-heart septectomy has brought the treatment of hypertrophic obstructive cardiomyopathy from the era of cardiopulmonary bypass and cardiac arrest to a new era of minimally invasive beating-heart surgery. In the past, there were few articles about the treatment of children with hypertrophic obstructive cardiomyopathy. This article reviewed the new progress and prognosis of surgical treatment of children with hypertrophic obstructive cardiomyopathy at home and abroad.

Management of the mitral valve in thoracoscopic trans-mitral myectomy for hypertrophic obstructive cardiomyopathy

ObjectiveThis study aimed to compare clinical outcomes of different mitral valve (MV) management methods in thoracoscopic transmitral myectomy (TTM) and guide surgeons' decision making for hypertrophic obstructive cardiomyopathy (HOCM). MethodsSeventy-three consecutive patients (41 females; mean age, 53.7 ± 13.6 years) with HOCM who underwent TTM between January 2019 and October 2022 were enrolled and divided into 3 groups according to MV surgical strategy. Clinical outcomes were analyzed and compared among the groups. ResultsNone of the patients experienced postoperative residual left ventricular outflow tract obstruction. Percentages of patients with mitral regurgitation (MR) grade ≥3+ (57.5% vs 1.4%) and systolic anterior motion (95.9% vs 2.7%) were significantly decreased postoperatively (P < .001 for both). The preoperative anterior mitral leaflet length was longer in patients in the anterior mitral leaflet direct reattachment group (median, 2.9 cm [interquartile range (IQR), 2.7-3.3 cm] vs 2.7 [IQR, 2.4-2.9 cm]; P = .018), but the postoperative coaptation length was shorter (mean, 8.3 ± 2.1 mm vs 11.1 ± 3.8 mm; P = .038). After a median echocardiography follow-up of 11.8 months, the left ventricular outflow tract gradient (LVOTG) and mitral regurgitation grades remained significantly improved in all 3 groups (P < .05 for all). ConclusionsTotal TTM in selected patients is safe and effective, and all 3 MV management strategies can significantly reduce the LVOTG while improving MR. Mitral valvuloplasty is the preferred initial management strategy over valve replacement except in the scenario of irreparable intrinsic MV disease and valvuloplasty failure.

Трансмитральная миоэктомия и протезирование митрального клапана из минидоступа при обструктивной гипертрофической кардиомиопатии

Primary hypertrophic cardiomyopathy is an isolated genetic heart disease characterized by thickening of the myocardium in the absence of an apparent hemodynamic cause. There are two patterns of the obstruction: static, with a muscle band narrowing the outflow tract of the left ventricle, and dynamic, which implies elongation of the anterior mitral valve leaflet. The key to correct treatment of the condition is understanding of the mechanism behind the obstruction. Myectomy is the gold standard of invasive treatment of obstructive hypertrophic cardiomyopathy; it aims to remove the static component of the obstruction. Another common adidition is the mitral valve surgery, aimed at elimination of the obstruction's dynamic component. This article presents a successful mini-invasive transmitral myectomy and mitral valve replacement in a case of obstructive hypertrophic cardiomyopathy with a damaged mitral valve.

Early outcomes of thoracoscopic trans-mitral myectomy in obstructive hypertrophic cardiomyopathy patients with left midventricular obstruction

Objective: To examine the early effect of thoracoscopic trans-mitral myectomy for hypertrophic cardiomyopathy patients with left midventricular obstruction. Methods: From April 2020 to July 2021, 10 hypertrophic cardiomyopathy patients with left midventricular obstruction underwent thoracoscopic trans-mitral myectomy at Guangdong Provincial People's Hospital. The whole group of patients consisted of 7 males and 3 females aged (52.0±16.4) years (range: 18 to 68 years). The EuroSCORE Ⅱ predicted mortality rate was 1.78% (1.20%) (M(IQR)) (range: 0.96% to 4.86%). The clinical data were collected and analyzed retrospectively to evaluate the clinical efficacy by comparing preoperative and postoperative echocardiographic parameters using paired t-test, paired Wilcoxon test or Fisher exact test, including left ventricular outflow tract peak pressure gradient, maximum interventricular septum thickness, systolic anterior motion of the anterior mitral leaflet and so on. The safety was determined by summarizing the incidence of perioperative and follow-up complications. Results: All the procedures successed with no conversion to median sternotomy, septal defect, ventricular rupture. There was no in-hospital 30-day death, neither serious complications like permanent pacemaker implantation, re-sternotomy for bleeding, low cardiac output syndrome, stroke, or multiple organ dysfunction syndrome. The left ventricular outflow tract obstruction was effectively relieved in all patients expect a patient developed residual obstruction. Compared with that of pre-operation, the thickness of the interventricular septum was significantly reduced from (22.1±4.0) mm to (10.3±1.7) mm (t=10.693, P<0.01), while the left ventricular outflow tract peak pressure gradient was significantly reduced from (81.7±21.1) mmHg to 12.3 (11.5) mmHg (Z=-2.805, P<0.01) (1 mmHg=0.133 kPa). Conclusion: Thoracoscopic trans-mitral myectomy is an effective and safe procedure for hypertrophic cardiomyopathy patients with left midventricular obstruction.

Minimally invasive cardiac surgery for complex procedures: extensive septal myectomy and double valve replacement

In this video tutorial, we demonstrate that minimally invasive cardiac surgery and all its benefits can be applied even to complex, multiple cardiac procedures. We present a 71-year-old patient with severely obstructive hypertrophic cardiomyopathy, moderate mitral regurgitation for systolic anterior motion of the mitral valve, moderate aortic stenosis and regurgitation and atrial fibrillation. We performed a mitroaortic valve replacement, transmitral and transaortic septal myectomy and left atrial appendage closure through a minimally invasive approach (right anterolateral minithoracotomy). After establishing peripheric cardiopulmonary bypass, aortic cross-clamping and a left atrium opening, the anterior mitral leaflet was incised circumferentially at its insertion on the annulus to allow an optimal transmitral myectomy. Subsequently, mitral valve removal was completed, and a bioprosthesis was implanted. After closure of the left atrium, the left atrial appendage was closed using a 40-mm device (Atriclip). The aorta was then opened, the aortic valve was excised and a transaortic septal myectomy was completed. Finally, a sutureless aortic bioprosthesis was implanted. Postoperative transoesophageal and transthoracic surgery demonstrated a residual left ventricular outflow tract gradient of 14 mmHg and the correct performance of both biological prostheses. Minimally invasive heart surgery can be offered even to patients requiring complex and multiple procedures, including septal myectomy. Combining the benefits of the operation with those of a minimally invasive approach may optimize postoperative and long-term surgical outcomes.

Thoracoscopic trans-mitral myectomy for hypertrophic obstructive cardiomyopathy: a retrospective single-centre study.

Transaortic myectomy is a common procedure for patients with hypertrophic obstructive cardiomyopathy. Thoracoscopic trans-mitral myectomy has been described in a few small-sample studies and has been recommended as preferable. We herein report our clinical outcomes using the thoracoscopic trans-mitral approach with 76 patients. This is a retrospective single-centre analysis of the safety and efficacy of thoracoscopic trans-mitral myectomy by comparing the clinical outcomes with that of transaortic myectomy. Between April 2019 and October 2021, 132 patients underwent either a transaortic (n = 56) or a thoracoscopic trans-mitral myectomy (n = 76). Compared with those in the transaortic group, patients in the trans-mitral group were more likely to be weaned off the ventilator within 24 h after surgery (80.3% vs 60.7%, P < 0.05) and to require a shorter duration of ventilation [29.01 (43.91) vs 51.12 (94.96) h, P = 0.08] and lower transfusion rate (26.3% vs 48.2%, P < 0.05). The in-hospital mortality rate of the transaortic and trans-mitral groups was 3.6% (n = 2) and 1.3% (n = 1), respectively. No significant inter-group differences were observed regarding in-hospital mortality, the incidence of low cardiac output syndrome or permanent pacemaker implantations. In the trans-mitral group, the thickness of the interventricular septum was significantly reduced postoperatively, with resultant relief of the left ventricular outflow tract obstruction [89.37 (27.5) vs 10.51 (0.65) mmHg, P < 0.01]. Transaortic myectomy also resulted in a significant reduction in left ventricular outflow tract gradient [90.41 (33.31) vs 11.35 (9.43) mmHg, P < 0.01]. And the incidence of residual systolic anterior motion of the trans-mitral group and the transaortic group was 2.67% and 1.9%, respectively. The thoracoscopic trans-mitral approach provides excellent exposure to the septum and anomalies of the mitral valve and papillary muscle. It relieves obstruction effectively, without increasing the incidence of major complications.

Primeval outcomes of thoracoscopic transmitral myectomy with anterior mitral leaflet extension for hypertrophic obstructive cardiomyopathy

The transaortic Morrow procedure is the current gold standard for hypertrophic obstructive cardiomyopathy (HOCM) patients who are resistant to maximum drug therapy. It is controversial whether concomitant mitral valve intervention is necessary. Only a few centers apply for concomitant anterior mitral leaflet extension with a bovine or autologous pericardial patch to further decrease systolic anterior motion. Our aim is to assess the primeval outcomes of thoracoscopic transmitral myectomy with anterior mitral leaflet extension (TTM-AMLE) in symptomatic HOCM patients. Between April 2019 and November 2020, 18 consecutive HOCM patients who underwent TTM-AMLE were enrolled in this study. Preoperative, postoperative, and follow-up outcomes were compared and statistically analyzed. The mean age was (50.17 ± 6.18) years and 10 (55.56%) were males. 18 (100%) patients had mitral regurgitation preoperatively, and they all successfully underwent TTM-AMLE with a median cardiopulmonary bypass and aortic cross-clamp time of 200.0 (150.8, 232.0), and 127.5 (116.0, 149.0) min, respectively. The median length of ICU stay was 2.7 (1.4, 5.2) days. The interventricular septum thickness was significantly reduced (from 18.03 ± 3.02 mm to 11.91 ± 1.66 mm, p < .001). There was no perioperative mortality, perforation of ventricular septum, or conversion to sternotomy observed. During a median follow-up of 18 months (IQR, 5-24 months), 1 (5.56%) patient had severe mitral regurgitation due to patch detachment and received reoperation. Moderate degree of mitral regurgitation and more than 50 mmHg in left ventricular outflow tract gradient were found in 2 (11.11%), and 1 (5.56%) patients, respectively. 1 (5.56%) patient who had second-degree atrioventricular block received permanent pacemaker implantation postoperatively. Overall, the maximum left ventricular outflow tract gradient (88.50 [59.50, 112.75] mmHg vs. 10.50 [7.00, 15.50] mmHg, p = .002), left ventricular outflow tract velocity (4.70 [3.86, 5.33] m/s vs. 1.60 [1.33, 1.95] m/s, p < .001) and the degree of mitral regurgitation (6.99 ± 4.47 cm2 vs. 2.22 ± 1.51 cm2 , p = .001) were significantly decreased, with a significant reduction in the proportion of systolic anterior motion (94.44% vs. 16.67%, p < .001). The TTM-AMLE is a safe and effective surgical approach for selected patients with HOCM. In our series, it provides excellent relief of left ventricular outflow tract obstruction, while significantly eliminating mitral regurgitation. The early outcomes of TTM-AMLE are satisfactory, but further studies and longer follow-ups are awaited.

Transmitral Septal Myectomy and Mitral Valve Surgery via Right Mini-Thoracotomy.

Transmitral myectomy for symptomatic hypertrophic obstructive cardiomyopathy is possible with existence of substantial mitral valve disease. We present herein our experience of minimally invasive transmitral septal myectomy combined with mitral valve surgery through right anterior mini-thoracotomy in the past 4 years at our institution. Between March 2017 and October 2020, 14 patients with hypertrophic obstructive cardiomyopathy and mitral valve disease required minimally invasive transmitral septal myectomy combined with mitral valve reconstruction or replacement at our institution. Mean age of patients was 54.2 ± 11.4 and 42.9% (n = 6) were female. Twelve patients (85.1%) were in New York Heart Association class III to IV and 6 patients (42.9%) presented with persistent atrial fibrillation. Clinical data were prospectively entered into our institutional database. Cardiopulmonary bypass time accounted for 140.2 ± 32.6 minutes and the myocardial ischemic time was 78.5 ± 12.4 minutes. Thirty-day mortality and overall mortality were zero. Peak ventricular outflow gradient decreased from 75.2 ± 12.7 to 9.4 ± 2.3 mm Hg (p < 0.0001). Simultaneously, mitral valve reconstruction and replacement were performed in 11 (78.6%) and 3 (21.4%) patients, respectively. No systolic anterior motion was seen in patients with mitral valve repair. No conversion to full sternotomy and/or rethoracotomy was noted. During a mean follow-up period of 24 ± 13 months, no patient required reoperation, no recurrence mitral regurgitation, and left ventricular outflow tract obstruction. Transmitral septal myectomy combined with mitral valve surgery through right anterior mini-thoracotomy can be performed safely with excellent surgical outcomes.

Combined mechanical mitral valve replacement and transmitral myectomy for hypertrophic obstructive cardiomyopathy treatment: An experience of over 20 years

BackgroundAlthough transaortic septal myectomy (TASM) is recognized as a standard procedure for treating hypertrophic obstructive cardiomyopathy (HOCM), occasionally the left ventricle (LV) intracavitary gradient remains postoperatively because of this technically demanding procedure. Mitral valve replacement (MVR) is sometimes chosen as an alternative option, but data on its long-term outcomes are lacking. Methods and resultsBetween 1991 and 2016, 29 patients [age, 14–82 (mean 58.9±15.9) years; 22 female patients (75.9%)] underwent combined mechanical MVR and transmitral myectomy. Of these, six patients had undergone MVR following a second cardiac arrest because of the residual LV outflow gradient or residual mitral regurgitation following TASM. Concomitant TASM was performed in 13 patients. The LV intracavitary gradient at rest assessed by transthoracic echocardiography significantly decreased postoperatively (16.8±19.1mmHg vs. 107.4±52.5mmHg, p<0.0001). Actuarial freedom rates from cardiac death were 92.8%, 89.0%, and 80.1% at 5, 10, and 15 years postoperatively, respectively. Sudden death occurred in three of the four patients who died of late cardiac complications. None of these patients with sudden death had implantable cardioverter-defibrillators. Most patients had maintained their LV end-diastolic dimension at <50mm for 10–15 years postoperatively. Actuarial freedom rates from hospitalization for heart failure were 87.7%, 82.2%, and 54.8% at 5, 10, and 15 years postoperatively, respectively. Occurrence rates of cerebral hemorrhage and infarction were 0.6% per patient-year and 1.3% per patient-year, respectively. ConclusionsCombined mechanical MVR and myectomy is an effective procedure to eliminate the LV intracavitary gradient in patients with HOCM. Although this procedure remains a viable option in certain situations, optimal medical treatment and close clinical follow-up along with the cooperation between cardiac surgeons and cardiologists are necessary to achieve favorable long-term outcomes.

Transmitral Septal Myectomy for Hypertrophic Obstructive Cardiomyopathy

Intrinsic abnormalities of the mitral valve are common in patients with hypertrophic cardiomyopathy and may need to be addressed at operation. Consecutive patients undergoing transmitral septal myectomy were retrospectively reviewed. The ventricular septum was exposed through a left atriotomy, and the anterior leaflet of the mitral valve was detached from its annulus. An extended myectomy was performed to the base of the papillary muscles. After myectomy, the anterior leaflet was reattached and concomitant mitral valve repair or replacement was performed. In some cases, we performed a modified anterolateral commissural closure suture, which served to reposition the lateral aspect of the anterior leaflet out of the left ventricular outflow tract ("curtain stitch"). Twenty patients who underwent this procedure were identified (70% women; mean age 63 years). Mitral regurgitation was moderate in 55% and severe in 40%. Preoperative peak left ventricular outflow tract gradient was 92 ± 43 mm Hg. Mitral valve repair (n= 11) or replacement (n= 9) was performed. Predischarge transthoracic echocardiography demonstrated a left ventricular outflow tract gradient of 10 ± 5 mm Hg. There was no operative mortality. Follow-up was 100% complete and averaged 22 ± 25 months. No patient required reoperation, and there was no recurrence of left ventricular outflow tract obstruction or mitral regurgitation greater than mild. Potential advantages of transmitral myectomy include a panoramic view of the septum and mitral subvalvular apparatus and the ability to simultaneously address mitral valve pathology. Consideration should be given to using the transmitral approach to septal myectomy as the preferred approach for the surgical treatment of hypertrophic cardiomyopathy.

Transmitral myectomy and how to deal with systolic anterior motion (SAM) in hypertrophic obstructive cardiomyopathy

Transmitral myectomy and how to deal with systolic anterior motion (SAM) in hypertrophic obstructive cardiomyopathy

Transmitral myectomy and how to deal with systolic anterior motion (SAM) in hypertrophic obstructive cardiomyopathy

Transmitral myectomy and how to deal with systolic anterior motion (SAM) in hypertrophic obstructive cardiomyopathy