Leerink analyst David Larsen says athenahealth announced that Kristi Matus is stepping down as CFO, with Karl Stubelis to serve as Senior Vice President and CFO. The analyst views this change as an "unfavorable event" and says it seems "unusual" that the CFO of a well-regarded firm would depart suddenly. While Larsen believes Stubelis will be "very capable" with regard to keeping the books, he has concerns regarding his leadership capabilities and ability to build and maintain trust with the investment community. Larsen has a Market Perform on the shares.