Zoll Medical Corp.’s plans to wake up the sleep apnea market segment advanced with the acquisition of Itamar Medical Ltd. for $538 million in cash. Itamar focuses on the diagnosis and treatment of sleep apnea, a common and complicating comorbidity of the cardiovascular patients served by Zoll. The deal continues Zoll’s acquisitive trend, following the purchase of Minnetonka, Minn.-based Respicardia Inc., another sleep apnea-focused company, in April and Therox Inc., of Irvine, Calif., in 2019. Zoll has operated as an Asahi Kasei Corp. subsidiary since its own acquisition by the Tokyo-based conglomerate in 2012. Zoll will acquire all outstanding shares of Itamar for $31 per American depository share (ADS) or $1.03 per ordinary share. The deal represents a more than 50% premium over the price of Itamar’s Nasdaq-listed ADS on Sept. 10. Itamar’s shares spiked 43.41% in premarket trading on news of the acquisition.