Mitral valve repair is underused in patients with hypertrophic obstructive cardiomyopathy.

Background: The optimal surgical approach for patients with hypertrophic obstructive cardiomyopathy (HOCM) with concomitant mitral valve (MV) regurgitation has remained controversial. The purpose of this study was to use the largest all-payer database in the United States to examine the strategy most commonly used for the correction of mitral valve pathology in the setting of HOCM.

Methods: The Nationwide Inpatient Sample (NIS) database was searched from 2005 to 2008 to identify patients with a diagnosis of HOCM (ICD-9-CM code 425.1) who underwent MV repair (ICD-9-CM code 35.12) or replacement (ICD-9-CM codes 35.23 and 35.24). HOCM patients who underwent MV repair and those who underwent MV replacement were compared with respect to baseline characteristics, repair rates, hospital mortality, and length of stay (LOS).

Results: MV repair was performed in 17.2% of cases (219/1255). Repair rates did not show a significantly increasing trend over time (P = .1419). The median LOS was significantly longer for replacement than for repair (11 days versus 7 days, P = .0001). The mortality rate for patients who underwent repair was 0.00%, compared with 11.18% for those who underwent replacement (P < .05).

Conclusions: The majority of patients with a HOCM diagnosis underwent MV replacement for the correction of MV pathology. Referral to centers with special expertise in treating patients with HOCM may positively affect the operative outcomes of this patient subset.