Original article
Adult cardiac
Mitral Valve Abnormalities in Hypertrophic Cardiomyopathy: Echocardiographic Features and Surgical Outcomes

https://doi.org/10.1016/j.athoracsur.2008.01.061Get rights and content

Background

Functional and intrinsic mitral valve (MV) abnormalities are common in hypertrophic cardiomyopathy (HCM); however, morphologic characteristics constituting indications for surgical intervention are incompletely defined. This study was conducted to define the echocardiographic features of MV pathology in patients with HCM and relate these to repairability of the MV, MV procedures performed, durability of repair, and survival.

Methods

From 1986 to 2003, 851 patients with HCM underwent operation, and 115 had a concomitant MV procedure. Detailed analysis of their 784 transthoracic and transesophageal echocardiograms, performed intraoperatively and postoperatively, was conducted. Outcomes were assessed by cross-sectional follow-up.

Results

Sixty-seven patients (58%) underwent MV repair, and 48 (42%) had MV replacement. The mean left ventricular outflow tract peak gradient was 70 ± 50 mm Hg. Systolic anterior motion was present in 95%. Valve abnormalities were degenerative in 36 (31%), myxomatous in 23 (20%), papillary muscle in 23 (20%), restrictive chordal in 22 (19%), restrictive leaflet in 80 (70%), and long leaflet in 64 (56%). Patients undergoing MV repair had higher prevalence of long leaflets and degenerative MV pathology. The anterior mitral leaflet was 3.0 ± 0.49 cm in the repair group vs 2.5 ± 0.40 cm in the replacement group (p = 0.0001). MV replacement patients were older, more symptomatic, and had more renal dysfunction and lower hematocrits. By 3 years, 91% of patients with a repair were free of reoperation.

Conclusions

Intrinsic MV pathology is frequently observed in HCM patients with symptomatic obstruction who undergo myectomy. Echocardiography can identify MV features predictive of successful valve repair. Repair, although durable, is feasible in only about half of patients.

Section snippets

Patients

From January 1986 to January 2003, 851 symptomatic patients underwent operation for HCM at The Cleveland Clinic. These 851 were established after personal review (B.W.L., N.G.S.) of all patients undergoing operation for HCM for any reason during this period, using consensus criteria [8]. Of these, 115 (14%) underwent a concomitant MV procedure, with 102 undergoing a concomitant septal myectomy, leaving 13 patients with HOCM who underwent MV replacement alone. Valve repairs were done in 67

Morphologic Features

Echocardiography documented restrictive leaflet abnormalities in 80 patients and elongated leaflets in 64 (Table 2). Degenerative and myxomatous pathologies were present in 59 (51%). Subvalvar chordal and papillary muscle abnormalities were found in 22 and 23 patients, respectively. Nearly all of the myxomatous valves had severe MR but the lowest LVOT gradients (Table 3); conversely, restricted chordal abnormalities were associated with the least prevalence of severe MR and the highest LVOT

Comment

Mitral valve abnormalities are common in patients with HCM, but their frequency and impact on surgical therapies is poorly defined. Limitations of previously published studies include small cohort size, focus on individual abnormalities, and focus on autopsy series. Our goal was to use echocardiographic analysis and our large experience with surgical therapy for HCM to define the spectrum of MV abnormalities, evaluate how they affect surgical therapies, and investigate durability of modern

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