Patients with aortic stenosis (AS) who undergo surgical aortic valve replacement (SAVR) live on average 1.9 years less than the general population, according to a study published in the July issue of the Journal of the American College of Cardiology. The younger a patient was when they underwent SAVR, the worse they fared in the long term.
The latest analysis of the SWEDEHEART registry, led by Natalie Glaser, MD, PhD, of the Karolinska Institutet in Stockholm, studied long-term relative survival and loss in life expectancy in patients treated with SAVR. AVR—whether it’s SAVR or transcatheter AVR—is the standard treatment for AS, which is present in 3.4% of patients aged 75 and up and has a poor prognosis once symptoms develop. Without treatment, a patient with severe AS can expect to live two to three years.
“After AVR, the prognosis is believed to be excellent and similar to that of the general population, especially in older patients,” Glaser and colleagues wrote in JACC. “However, studies providing data regarding prognosis after AVR in relation to the general population are scarce, particularly in younger patients.”
Glaser et al.’s study included 25,528 patients from the SWEDEHEART cohort who underwent primary SAVR with or without concomitant coronary artery bypass grafting between 1995 and 2013. The researchers linked SWEDEHEART data to other national health registers to obtain patients’ baseline characteristics and vital status, and those life expectancies were compared with expected survival rates in the general Swedish population.
The authors followed up with patients for an average of 6.8 years. The 19-year observed, expected and relative survival rates were 21%, 34% and 63%, respectively. Participants lost an average 1.9 years of their lives after SAVR, and that estimated loss increased with younger age (0.4 years less in patients under 80; 4.4 years less in patients under 50).
In a related editorial, Andras P. Durko, MD, and Arie Pieter Kappetein, MD, PhD, both of Erasmus University Medical Center in Rotterdam, the Netherlands, said the marked loss in life expectancy in younger SAVR patients “is thought-provoking and needs explanation.” They said younger patients more frequently receive a mechanical valve prosthesis, which necessitates lifelong anticoagulation and could contribute to impaired long-term survival.
The editorialists also noted the fact that while comparing survival after SAVR with survival in a matched general population was “an elegant way to place to results in a proper perspective,” the groups are incomparable in certain ways. Different comorbidities, for one, could have different bearings on one’s life expectancy, and the etiology and morphology of AS aren’t uniform across all age groups. Younger patients tend to have congenitally bicuspid or unicuspid valves; patients over 70 years more often have degenerative AS with tricuspid valves.
“Can loss in life expectancy after SAVR be prevented?” Durko and Kappetein wrote. “Besides efforts to avoid complications during follow-up, optimizing the timing of valve replacement can also improve life expectancy after SAVR.
“The loss in life expectancy after SAVR reported by Glaser et al. can be considered substantial, and the reasons deserve further investigation. Optimizing the timing of intervention might be particularly important in younger patients with AS to minimize loss in life expectancy after aortic valve replacement.”