Cardiovascular Systems Inc. posted disappointing financial results Tuesday as COVID-19 continues to constrain hospitals, resulting in fewer elective surgeries.

The New Brighton-based medical device company saw revenue drop 3.6% in its first quarter for fiscal year 2022, which ended Sept. 30. The Delta variant of the virus has prolonged the pandemic's effect on medical facilities, leading to staffing shortages and delayed procedures at hospitals.

"The negative impact due to the Delta variant was larger than anticipated," said Scott Ward, chairman, president and CEO of CSI, in a conference call with investors.

Cardiovascular Systems (CSI) makes catheter-based platforms to treat coronary and peripheral artery disease.

The company reported $58.4 million in quarterly revenue, with a net loss of $8.6 million. That was below analysts' expectations and notably deeper in the red than the $2.1 million net loss for the same quarter last year.

CSI's stock was fell 16% in trading on Tuesday.

The company had issued a warning in September about COVID-19's impact to its business.

The biggest hits came from the South and Southeastern U.S., in states like Florida and Texas. Those regions typically represent more than 50% of CSI's revenue, Ward said.

Looking ahead, he said, "The pace of recovery is difficult to predict."

Analysts had been expecting a loss of $0.10 per share for the quarter. Instead, CSI reported a net loss of $0.22 per share.

The company also significantly cut its full year financial guidance. It now expects revenue in the range of $265 million to $285 million, down from a range of $295 million to $305 million. CSI expects to post a net loss this year of 5 to 8%.