Device-detected congestion is associated with worse patient-reported outcomes in heart failure

Background
Congestion is a common cause of symptoms in heart failure (HF). Yet, intrathoracic impedance, an objective marker of cardiopulmonary congestion, has not been examined in relation to HF symptoms.

Objective
To determine whether device-detected cardiopulmonary congestion is a predictor of physical and psychological symptoms and health-related quality of life (HRQOL) in adults with HF over 3 months.

Methods
Multivariate generalized linear modeling was used to quantify the association of cardiopulmonary congestion (Optivol® Index exceeding 60 Ω threshold) with HRQOL (12-item Kansas City Cardiomyopathy Questionnaire) and both physical symptoms (Functional Assessment of Chronic Illness Therapy-Fatigue Scale; HF Somatic Perception Scale Dyspnea and Early & Subtle Symptoms subscales) and affective symptoms (9-item Patient Health Questionnaire; 6-item Patient-Reported Outcomes Measurement Information System Anxiety Scale).

Results
The mean age of the sample (n = 49) was 62years old, 39% were women, and 63% had NYHA class III/IV HF. Participants who experienced threshold crossings in the previous 90days reported on average, 130% higher dyspnea (p = 0.017; confidence interval (CI) 10.2%, 437%), 40% higher early & subtle symptoms (p = 0.029; CI 3.4%, 89.7%), 106% higher depressive symptoms (p = 0.003; CI 19.1%, 257%) and 40% higher anxiety (p = 0.028; CI 3.7%, 89.1%). Threshold crossings in the previous 90days were also significantly associated with a clinically meaningful decrease in HRQOL (β = −16.16 ± 6.32; p = 0.01).

Conclusions
Intrathoracic impedance measured with the Optivol Index can provide additional information regarding the patient experience of hallmark physical and psychological HF symptoms and HRQOL over 3months.