Wide Variation in TAVI Readmission Rates Among US Hospitals

Despite documented declines in 30-day readmission rates after TAVI, there is considerable variation across centers in the United States that is not explained by hospital characteristics alone, a new study suggests.

In fact, the likelihood of being readmitted at 30 days was roughly 60% higher when patients were treated at a hospital that was 1 standard deviation (SD) above the national average for readmission rates versus 1 SD below the national average, report investigators.

Lead author Dhaval Kolte, MD, PhD (Massachusetts General Hospital, Boston), explained that 85% of the variation they saw could not be attributed to differences in patient characteristics, length of stay, and discharge disposition. “What we concluded was that the unexplained variation in the hospital readmission rates was not explained internally by the hospital-level practices, so there likely are other unmeasured variables that could include patient-level factors such as social determinants of health, which are not captured in these databases, as well as certain hospital practices that also are difficult to capture,” Kolte told TCTMD.

Contemporary data suggest that 30-day all-cause readmission rates for TAVI patients range from 16% to 21%, and that rates have been on the decline overall, he added. In the new study, readmission rates ranged dramatically from zero to 40%. Kolte said in order to get at what is going on in the outlier hospitals—those with either above- and below-average post-TAVI readmission rates—future research should be directed at qualitative/mixed-method studies to understand programs or practices that help or hinder prevention of readmissions.

In the paper, published in the Journal of the American Heart Association ahead of a planned presentation at the upcoming American College of Cardiology 2021 Scientific Session, Kolte and colleagues examined data from the Nationwide Readmissions Database on 325 hospitals that performed five or more TAVIs that year. The total number of procedures included was 27,091.

After multivariable adjustment for patient characteristics, the median risk-standardized readmission rate was 11.9% (ranging from 8.8% to 16.5), with a predicted odds ratio of 1.59 (95% CI; 1.39-1.77) if treated at a hospital 1 SD above the average compared with a hospital 1 SD below the average.

Searching for Reasons for Readmission

Only 15% of the between-hospital variation was attributable to differences in length of stay and discharge disposition, despite some prior studies showing those factors to be among the potential contributors to readmission. After adjusting for patient characteristics, there was no significant correlation between 30-day readmissions and hospital bed size, control/ownership, teaching status, location, or TAVI volume. However, weak statistical significance was seen between 30-day readmission and having SAVR or PCI, as well as having other conditions such as acute MI, heart failure, or pneumonia.

Compared with the top 5% of hospitals, those in the middle 90% and those in the bottom 5% had fewer  cardiac readmissions and more noncardiac readmissions, particularly those related to gastrointestinal, renal, and endocrine causes. Cardiac readmissions were predominantly conduction disorders and dysrhythmias, which Kolte and colleagues say “may reflect a trend toward early discharge after TAVR, and is consistent with findings from a recent study that showed an increase in the proportion of permanent pacemaker implantations during a subsequent hospitalization after the index TAVR.”

Kolte said most of the data on methods for reducing high rates of readmissions have come from the acute MI and HF literature and show that medication reconciliation and discharge planning and transition teams may be helpful. Additionally, hospital characteristics specific to TAVI, such as availability of stroke neurology, electrophysiology, and vascular surgery services, may be more-important factors in improving postprocedural care, especially for patients with complications.

Another possibility is lack of communication and understanding about when TAVI patients need to be readmitted. For example, Kolte said it’s possible that some patients with noncardiovascular emergency department presentations are readmitted out of misplaced caution.

“In [some of] the bottom 5% hospitals, it may be that the emergency physicians are just more inclined to admit patients because they recently had a TAVR, versus some of the top 5% hospitals where they may have pathways so the emergency physicians can get in touch with the TAVR operator or team to discuss the disposition of the patient rather than having to readmit,” he said. “I think we need to look more closely at the reasons and ways that patients get readmitted after TAVR at low-performing hospitals.”