A Novel and Simple Exercise Test Parameter to Assess Responsiveness to Cardiac Resynchronization Therapy

• Published in: Diagnostics (Basel) Vol. 10; no. 11; p. 920
• Main Authors: Cozlac, Alina-Ramona, Petrescu, Lucian, Crisan, Simina, Luca, Constantin Tudor, Vacarescu, Cristina, Streian, Caius Glad, Lazar, Mihai-Andrei, Gurgu, Andra, Dragomir, Angela, Goanta, Emilia Violeta, Vatasescu, Radu, Chahine, Kandara Mohamed, Rachieru, Ciprian, Cozma, Dragos
• Format: Journal Article
• Language: English
• Published: MDPI 09.11.2020; MDPI AG
• Subjects: cardiac resynchronization therapy; exercise test; heart rate recovery index; non-responder; responder
• DOI: 10.3390/diagnostics10110920
• ISSN: 2075-4418

This study assessed the value of heart rate recovery index (HRRI), a new parameter of an exercise test, as the predictor of response to cardiac resynchronization therapy (CRT). Methods: Consecutive patients receiving a CRT device were followed up after implantation and every 6 months. An effort test (ET) was quantified by minimum heart rate/maximum heart rate, as well as acceleration and deceleration times. HRRI was calculated as the ratio between acceleration and deceleration time (AT/DT) and compared to outcome. We used logistic regression to assess the predictive value of HRRI for responders and non-responders to CRT. The area under the curve (AUC) was computed to distinguish between positive and negative outcomes. Results: A total of 109 patients (74 men, mean age 63.3 ± 9.8 years) were analyzed; permanent long-term fusion CRT pacing was possible in 65 patients. Patients were assigned to two groups: responders and non-responders (98/11 patients). During a mean follow-up of 36 months, 545 ETs were performed. HRRI was significantly higher in responders versus non-responders (3.16 ± 2 vs. 1.4 ± 0.5, p < 0.001). The optimal cutoff value for HRRI as a predictor of CRT response was 1.51 (area under the receiver operating characteristic (ROC) curve = 0.844). Responders had significant left-ventricular (LV) reverse remodeling (LV end-diastolic volume = 240 ± 90 mL vs. 217 ± 89 mL, p < 0.001) and higher LV ejection fraction (26 ± 5.8% vs. 35 ± 8.7%, p < 0.001). Conclusions: HRRI computation during routine ET is useful for the evaluation of responsiveness to CRT.