Mortality risk in patients undergoing surgery for infective endocarditis (IE) significantly increases with age, with a mortality of 20% in patients aged 75 years or older, and is further augmented by previous cardiac surgery, heart valve implantation prior to IE admission, and diabetes, according to a study recently published in BMC Infectious Diseases.
More patients with IE are now older at the time of diagnosis, are majority male, and are more likely to have a prosthetic heart valve. Previous analyses suggested that age and type of surgical intervention may be associated with mortality rate in patients with IE. This study examined how age and type of left-sided surgical intervention modified mortality in patients undergoing surgery for IE.
In total, 1767 patients with first-time IE undergoing surgical treatment from 2000 to 2017 were included from nationwide Danish registries. Patients were grouped by the following age categories: less than 60 years of age, 60 to 74 years of age, and 75 years of age or older. The primary outcome was 90-day all-cause mortality after valve surgery.
For the age groups less than 60 years of age, 60 to 74 years of age, and 75 years of age or older, the proportions of patients undergoing surgery were 35.3%, 26.9%, and 9.1%, respectively. The 90-day mortality was 7.5%, 13.9%, and 22.3% (P <.001), respectively. Patients 60 to 74 years of age (hazard ratio [HR], 1.84; 95% CI, 1.48-2.29) and 75 years of age or older (HR, 2.47; 95% CI, 1.88-3.24) experienced higher mortality compared to patients less than 60 years of age. When age was included as a continuous variable, each 1-year increase was associated with an increased risk of mortality (HR, 1.04; 95% CI, 1.02-1.05).
In-hospital mortality for patients undergoing aortic valve surgery increased with increasing age group (P <.001). Odds of in-hospital mortality were higher in patients undergoing isolated mitral valve surgery (odds ratio [OR], 2.15; 95% CI, 1.42-3.26) and combination of aortic and mitral valve surgery (OR, 2.99; 95% CI, 1.94-4.62) compared to aortic valve surgery. The 90-day mortality and 5-year mortality increased with higher age groups (P <.001; P =.07, respectively).
Other factors associated with higher 90-day mortality include diabetes and prosthetic heart valve implantation prior to IE admission. Among patients 75 years of age or older, 36% who were undergoing a combination of aortic and mitral valve surgery died within 90 days of surgery.
Limitations of the study include lack of echocardiography to characterize infectious spread on cardiac structures and lack of data on surgery indications and microbiological etiologies.
The study “showed that [in] patients 75 years [of age or older] who underwent surgery, the in-hospital and 90-day mortality was tripled compared with patients 60 years [of age or younger],” researchers concluded.
Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Østergaard L, Smerup MH, Iversen K, et al. Differences in mortality in patients undergoing surgery for infective endocarditis according to age and valvular surgery. BMC Infect Dis. 2020;20(1):705. doi: 10.1186/s12879-020-05422-8