Analysis of Geographic Variations in the Diagnosis and Treatment of Patients With Aortic Stenosis in North Carolina

Despite advances in the treatment of aortic stenosis (AS), many patients with AS remain untreated. Barriers to accessing cardiovascular surgical care may play a role in this undertreatment. We sought to examine whether there are geographic variations in the treatment of AS within North Carolina that may reflect differential access to care. Hospital discharge data from North Carolina hospitals during federal fiscal year 2010 were analyzed from the Thomson Reuters database. Patients hospitalized with AS were identified using International Classification of Diseases, ninth revision (ICD-9) diagnosis codes. ICD-9 procedure codes were used to identify patients who had aortic valve replacement and other cardiac procedures. The rates of hospitalizations for AS and aortic valve replacement were calculated per county in North Carolina. In fiscal year 2010, there were 12,111 patients who were discharged from a North Carolina hospital with AS listed as one of the ICD-9 discharge diagnosis codes. The median age for this population was 79 (twenty-fifth to seventy-fifth), with approximately 1/3 patients (28.9%) being at least 85 years of age and >1/2 being female (53.8%). Of them, 1,608 patients underwent valvular surgery with an in-hospital mortality rate of 3.3%. The highest rates, corrected for county population, of hospitalizations where AS was listed as the primary diagnosis were in the most rural segments of North Carolina while those same areas had the lowest rates of valvular surgery. In conclusion, there are significant geographic variations in the rates of hospitalization for AS and for valvular surgery within North Carolina. The most rural segments of the state have the highest rates of hospitalization while also having the lowest rates of surgery. This suggests geographic treatment disparities as a result of access to surgical care that must be considered as new therapies for AS, such as transcatheter aortic valve replacement, are deployed.