# Prospective Study on the Evaluation of Echocardiographic Parameters as Predictors of a Positive Response to Cardiac Resynchronization Therapy in a Tertiary Care Hospital in Mexico

## TL;DR

This study identifies two echocardiographic parameters that predict whether patients will benefit from cardiac resynchronization therapy for heart failure.

## Contribution

The study demonstrates that Global Longitudinal Strain and the Kapetanakis index are strong predictors of CRT response.

## Key findings

- 14 out of 33 patients (42%) responded positively to CRT based on a ≥15% reduction in left ventricular end-systolic volume.
- Baseline Global Longitudinal Strain and Kapetanakis index showed significant differences between responders and non-responders.
- A strong positive correlation (ρ = 0.663) was found between CRT response and improved quality of life.

## Abstract

Background/Objectives: Heart failure is a major global health problem. Among the available treatment options, cardiac resynchronization therapy (CRT) has been shown to improve both quality of life (QoL) and mortality; however, not all patients respond adequately. Our study aimed to identify echocardiographic parameters that predict a positive response to CRT. Methods: A total of 33 patients (10 women and 23 men) were prospectively recruited, all met the standard criteria for CRT implantation. Biochemical, clinical, QoL, 6 min walk test, and echocardiographic evaluations were performed prior to CRT implantation and reassessed after 6 months. A ≥15% reduction in left ventricular end-systolic volume was taken as the defining parameter of positive response. Based on response level, patients were divided into two groups: responders and non-responders. Results: Comparing the overall population before and after CRT, a positive impact was observed on biochemical, electrocardiographic, and echocardiographic parameters. Fourteen patients (42%) were classified as responders and nineteen (58%) as non-responders. Only two basal echocardiographic parameters showed significant baseline differences between groups: Global Longitudinal Strain (GLS) and the Kapetanakis index. ROC curve analysis showed that baseline GLS and Kapetanakis index had excellent discriminative ability for predicting CRT response. Also, binary logistic regression analysis identified the association of GLS and Kapetanakis index with CRT response. Finally, Rho Spearman analysis showed a positive correlation between the degree of response to CRT and the QoL, (ρ) of 0.663 with p = 0.001. Conclusions: Our findings confirm the overall clinical, biochemical, echocardiographic, and QoL benefits of CRT. In addition, two echocardiographic parameters proved to be potential response predictors.