Percutaneous Versus Surgical Treatment for Patients With Hypertrophic Obstructive Cardiomyopathy and Enlarged Anterior Mitral Valve Leaflets

Abstract

Background-The purpose of this study was to compare percutaneous transluminal septal myocardial ablation (PTSMA) and septal myectomy combined with mitral leaflet extension (MLE) in symptomatic hypertrophic obstructive cardiomyopathy patients with an enlarged anterior mitral valve leaflet (AMVL). Both PTSMA and myectomy reduce septal thickness and left ventricular outflow tract (LVOT) gradient; however, an uncorrected enlarged AMVL may predispose to residual systolic anterior motion (SAM) after successful standard myectomy or PTSMA. Myectomy with MLE previously demonstrated superior hemodynamic results compared with standard myectomy, but its value relative to PTSMA is unknown. Methods and Results-Twenty-nine patients (aged 44Ϯ12 years) underwent myectomy with MLE, and 43 patients (aged 52Ϯ17 years) underwent PTSMA. Mitral leaflet area was similar in both groups (16.7Ϯ3.4 versus 15.9Ϯ2.7 cm 2 , respectively). After PTSMA, 2 patients died, 4 needed a reintervention, and 4 required a permanent pacemaker for complete heart block. After surgery, only 1 patient needed a reintervention. At 1-year follow-up, LVOT gradients did not differ between surgical and PTSMA patients (17Ϯ14 versus 23Ϯ19 mm Hg, respectively). Preinterventional mitral regurgitation grade was more severe in the surgical group, but with myectomy combined with MLE, the residual grade was similar to that of PTSMA. Mean SAM grade decreased significantly more after surgery (from 2.9Ϯ0.3 to 0.5Ϯ0.7 mm Hg versus from 2.8Ϯ0.5 to 1.3Ϯ0.9 mm Hg, PϽ0.05). Conclusions-PTSMA in these selected patients with hypertrophic obstructive cardiomyopathy had more periprocedural complications and resulted in more reinterventions. Hemodynamic results (SAM grade and reduction in mitral regurgitation) were better in surgical patients. (Circulation. 2005;112:482-488.)

Contemporary Insights and Strategies for Risk Stratification and Prevention of Sudden Death in Hypertrophic Cardiomyopathy

“…Although there is concern, no definitive evidence is yet available at this relatively early juncture that the alcohol septal ablation scar per se increases (or does not increase) the long-term risk for SD in absolute terms, and resolution will require greatly extended follow-up studies in large patient cohorts. 63 There is, however, a documented risk for potentially lifethreatening sustained ventricular tachyarrhythmias largely over the short-term 8,[55][56][57][58][59][60][61][62] (with reported postprocedural annual event rates of 3% to 5% 58,61 ) presumably resulting from electrical instability potentiated by the scar in certain susceptible patients. On the basis of this consideration and a measure of concern that alcohol-imposed infarcts could compound preexisting and underlying myocardial electric instability, 8,9,54,55,57,59 some practitioners have considered alcohol septal ablation a risk arbitrator and prudently implanted ICDs in selected patients with commonly accepted risk markers after the ablation procedure.…”

Surgical Septal Myectomy Versus Alcohol Septal Ablation

“…[8][9][10][11][12][13][14][15][16][17][18][19] In addition, ASA is ineffective in patients with substantial LV hypertrophy (>25-mm wall thickness), since sufficient septal thinning cannot be reliably achieved.…”

“…[1][2][3][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25] Whereas any intervention that relieves outflow gradient (and normalizes LV pressures) will improve symptoms and reverse the progression of heart failure in properly selected HCM patients, myectomy produces more complete gradient relief, 11,[18][19][20]23,27,28 particularly in patients <65 years of age. 10 Gradient reduction with ASA is generally most favorable in older patients >65 years of age who have lesser degrees of LV hypertrophy, 10 consistent with the guidelines that favor ASA as a potential surgical alternative largely in patients of advanced ages.…”

“…7 The most recent of these conversations concerns the most effective strategy for reducing gradient and symptoms, triggered by the introduction of catheter-based percutaneous alcohol septal ablation (ASA) as an alternative to myectomy. [8][9][10][11][12][13][14][15][16][17][18][19] The nonsurgical technique, introduced by Professor Ulrich Sigwart at the Royal Brompton Hospital in 1994, 8 involves injection of 1 to 4 mL of 96% ethanol into the first septal perforator branch of the left anterior descending coronary artery to produce a basal septal myocardial infarction and ultimately remodeling of the LV outflow tract. ASA avoids the recovery time with loss of work, residual discomfort, and anxiety associated with surgery.…”

Long-term outcome of simultaneous septal myectomy and anterior mitral leaflet retention plasty in hypertrophic obstructive cardiomyopathy: the Berlin experience

“…Multifaceted approaches aiming to repair the MV and abolish SAM have been introduced by several surgeons, in addition to the fundamental septal myectomy. They include leaflet resection for an unsupported scallop of the posterior leaflet and artificial chordae or plication for an unsupported scallop of the anterior mitral leaflet (AML) with selective use of a flexible posterior annuloplasty band (1), complete resection and replacement of all AML chordae with the loop technique (2), radical debridement and repositioning of the papillary muscles (3), complete excision of secondary chordae of the AML (4), triangular resection of the anterior leaflet (5), AML extension with a pericardial patch (6,7), sliding plasty of the posterior leaflet (8), edge-to-edge-technique (1,9,10), or release of papillary muscles and plication of the AML (11).…”