Management of Heart Failure In Cardiac Amyloidosis Using An Ambulatory Diuresis Clinic: An Analysis of Safety And Health Care Utilization

Abstract

Background Restrictive cardiomyopathy in cardiac amyloidosis (CA) mainly occurs due to light chain (AL) or transthyretin (ATTR) protein deposition in the myocardium. Recurrent congestion related to HF can be challenging to manage in CA, often requiring high dose diuretics and frequent hospitalizations. Though therapies are available for CA that may prolong survival, these do not reverse the cardiomyopathy that may be present at time of diagnosis. Innovative outpatient strategies are needed to effectively manage HF in patients with CA. Methods The Johns Hopkins Heart Failure Bridge Clinic is an outpatient HF disease management clinic with the ability to administer intravenous (IV) diuretics. We retrospectively studied patients with CA seen in the clinic in 2017 for 1) safety outcomes of IV diuresis visits and 2) health care utilization at 30, 90, and 180 days pre- vs. post-index clinic visit. Results Forty-four patients with CA (mean age 71.3±9.7 yrs, 17 AL, 27 ATTR; 75% male, 48% AA) had 203 clinic visits (56 for IV diuresis) over 6 months. Oral diuretic dosage was decreased at 29 (14%) visits and increased at 67 (33%) visits. There was no severe acute kidney injury or symptomatic hypotension with IV diuresis. Eight (14%) IV diuretic visits resulted in asymptomatic hypotension, with 4 events in 1 AL patient (Table 1). There was a large decrease in ED and inpatient visits and associated charges when comparing pre- to post-index visit time periods (Figure 1). The proportion of days hospitalized/1000 patient days of follow-up decreased as early as 30 days (147.3 vs 18.1/1000 patient days of follow-up, p<0.001) and persisted through 180 days (33.6 vs 22.9/1000 patient days of follow-up, p<0.001) pre- vs. post-index clinic visit (Figure 1). Conclusion This is the first description of the use of an outpatient diuresis clinic to manage HF in cardiac amyloidosis. Outpatient IV diuretic administration is safe and HF management in this setting reduces acute care utilization in a patient population that contributes to a high health care burden. Restrictive cardiomyopathy in cardiac amyloidosis (CA) mainly occurs due to light chain (AL) or transthyretin (ATTR) protein deposition in the myocardium. Recurrent congestion related to HF can be challenging to manage in CA, often requiring high dose diuretics and frequent hospitalizations. Though therapies are available for CA that may prolong survival, these do not reverse the cardiomyopathy that may be present at time of diagnosis. Innovative outpatient strategies are needed to effectively manage HF in patients with CA. The Johns Hopkins Heart Failure Bridge Clinic is an outpatient HF disease management clinic with the ability to administer intravenous (IV) diuretics. We retrospectively studied patients with CA seen in the clinic in 2017 for 1) safety outcomes of IV diuresis visits and 2) health care utilization at 30, 90, and 180 days pre- vs. post-index clinic visit. Forty-four patients with CA (mean age 71.3±9.7 yrs, 17 AL, 27 ATTR; 75% male, 48% AA) had 203 clinic visits (56 for IV diuresis) over 6 months. Oral diuretic dosage was decreased at 29 (14%) visits and increased at 67 (33%) visits. There was no severe acute kidney injury or symptomatic hypotension with IV diuresis. Eight (14%) IV diuretic visits resulted in asymptomatic hypotension, with 4 events in 1 AL patient (Table 1). There was a large decrease in ED and inpatient visits and associated charges when comparing pre- to post-index visit time periods (Figure 1). The proportion of days hospitalized/1000 patient days of follow-up decreased as early as 30 days (147.3 vs 18.1/1000 patient days of follow-up, p<0.001) and persisted through 180 days (33.6 vs 22.9/1000 patient days of follow-up, p<0.001) pre- vs. post-index clinic visit (Figure 1). This is the first description of the use of an outpatient diuresis clinic to manage HF in cardiac amyloidosis. Outpatient IV diuretic administration is safe and HF management in this setting reduces acute care utilization in a patient population that contributes to a high health care burden.