Patients with an infection of the inner lining on the left side of the heart (endocarditis) who were switched from intravenous to oral antibiotic therapy had better long-term survival and fewer complications than similar patients who remained on conventional intravenous antibiotic therapy, according to research presented at the American College of Cardiology’s 68th Annual Scientific Session.

Therapeutic approach

While initial six-month data is shows that partial treatment with oral antibiotics is similar in efficacy and safety to conventional intravenous therapy for left-sided infectious endocarditis, longer follow-up (median of 3.5 years) demonstrates this therapeutic approach is better for patients; said Henning Bundgaard, MD, PhD, DMSc, professor of cardiology at the Heart Center at the National University Hospital in Copenhagen, Denmark, and the study’s lead author.

“In stabilized patients with left-sided infectious endocarditis, a switch from intravenous to oral antibiotic therapy showed superior efficacy and safety compared with continued intravenous treatment,” he said. “These findings clearly support a change in the standard of care for this condition.”

Infectious endocarditis

People with pre-existing heart valve disease, previous endocarditis; prosthetic heart valves or other implanted cardiac devices have an elevated risk for infectious endocarditis. The condition most often occurs on the left side of the heart in the mitral or aortic valve. Men are diagnosed with infectious endocarditis about twice as often as women.

The current study, known as POET, is the largest randomize trial of patients with infectious endocarditis, and was design to test whether oral antibiotic therapy for left-sided infectious endocarditis was at least as effective and safe as intravenous treatment. Clinical guidelines from several professional organizations currently recommend treating left-sided infectious endocarditis with intravenous antibiotics for up to six weeks.

During the initial treatment phase, patients often need intensive care and close monitoring. Because intravenous antibiotics are logistically difficult to administer outside of a hospital; most patients remain in the hospital for the duration of their treatment. Studies have suggested that intravenous treatment during long hospital stays may put patients at increased risk for complications.

Completed antibiotic therapy.

Oral antibiotics would allow patients to leave the hospital sooner and complete their treatment at home. Studies in other conditions have shown that patients with shorter hospital stays generally had better outcomes. A total of 400 patients (average age 67 years; 77 % male) with left-side infectious endocarditis are enroll in the study.
Study participants had to be in stable condition and to have had a satisfactory response to at least 10 days of intravenous antibiotic treatment before randomization. They are then randomly assign to either continue with ; intravenous antibiotics or ;switch to oral treatment for an average of 17 days after they are diagnose. Intravenously-treated patients remain in the hospital until they complete antibiotic therapy. Patients who switch to oral treatment are discharge from the hospital a median of three days after making the switch.