This bacterial infection, called infective endocarditis, often affects young, poor white men who share needles. Many also have HIV, hepatitis C and alcohol abuse, the researchers said.
Looking at data on nearly 1 million patients with infective endocarditis, the investigators found that drug abuse was involved in 16% of cases in 2016 -- twice the percentage seen in 2002.
"Nationwide, public health measures need to be implemented to address this epidemic, with targeted regional measures specifically addressed to patients at risk," said lead researcher Dr. Serge Harb. He's an assistant professor of medicine at Cleveland Clinic's College of Medicine, in Ohio.
To combat the increase in infective endocarditis, teams are needed that include cardiologists, infectious disease specialists, cardiac surgeons, nurses, addiction specialists, case managers and social workers, he said.
"Appropriately treating the infection is only one part of the management plan," Harb said. "Helping these patients address their addictive behaviors, providing social support, and getting them to effective rehabilitation programs are key aspects in their optimal care and to prevent relapses."
Infective endocarditis develops when bacteria gets into the bloodstream and attacks the heart's lining or valves. It can lead to stroke, a leaky heart valve, heart failure and abscesses around the heart valve.
Drug abuse is a primary risk factor for endocarditis, Harb said.
Each year in the United States, more than 30,000 people are treated for infective endocarditis. For one in five, it's fatal.
For the new study, Harb and his colleagues used the National Inpatient Sample registry from 2002 to 2016.
While increases in the infection were seen nationwide, the biggest increase was in the Midwest. There, the rate increased nearly 5% each year, Harb's team found.
The investigators also found that white men, median age 38, were most affected. Also, these drug-using patients were poorer: 42% had incomes in the bottom quarter of the population, and almost half relied on Medicaid for their health care.
The drug users with endocarditis stayed in the hospital longer and were more likely to need heart surgery. But because most were young, they were less likely to die, the researchers noted.
Dr. Gregg Fonarow is a professor of cardiology at the University of California, Los Angeles. He said that infective endocarditis "is a serious, potentially life-threatening condition that results in substantial morbidity and health care expenditures."
Concerns have been raised about the increase over the last decade brought on by the opioid epidemic, Fonarow added.
"The substantial rise in drug abuse associated with infective endocarditis further highlights the devastating effects the opioid epidemic has had in the United States, and why intensive efforts are needed to further address this serious public health issue," Fonarow said.
The report was published online Sept. 18 in the Journal of the American Heart Association.