Effects of Trypanocidal Treatment on Echocardiographic Parameters in Chagas Cardiomyopathy and Prognostic Value of Wall Motion Score Index: A BENEFIT Trial Echocardiographic Substudy

J Am Soc Echocardiogr. 2019 Feb;32(2):286-295.e3. doi: 10.1016/j.echo.2018.09.006. Epub 2018 Nov 9.

Abstract

Background: Serial echocardiographic studies in chronic Chagas cardiomyopathy are scarce. The aims of this study were to evaluate whether therapy with benznidazole modifies the progression of cardiac impairment and to identify baseline echocardiographic parameters related to prognosis.

Methods: A prospective substudy was conducted in 1,508 patients with chronic Chagas cardiomyopathy randomized to benznidazole or placebo, who underwent two-dimensional echocardiography at enrollment, 2 years, and final follow-up (5.4 years). Left ventricular (LV) ejection fraction, LV wall motion score index (WMSI), indexed left atrial volume, and chamber dimensions were collected and correlated to all-cause death and a composite hard outcome using univariate and multivariate analyses.

Results: At enrollment, most patients had normal chamber dimensions, and 70.5% had preserved LV ejection fractions. During follow-up, all chamber dimensions increased similarly in both treatment arms. LV ejection fraction was comparably reduced (55.7 ± 12.7% to 52.1 ± 14.6% vs 56.3 ± 12.7% to 52.8 ± 14.1%) and LV WMSI similarly increased (1.31 ± 0.41 to 1.49 ± 0.03 and 1.27 ± 0.38 to 1.51 ± 0.03) for the benznidazole and placebo groups, respectively (P > .05). A higher baseline LV WMSI was identified in subjects who died compared with those alive at final echocardiography (1.76 ± 0.517 vs 1.271 ± 0.393, P < .0001). There was a significant (P < .0001) graded increase in the risk for the composite outcome with worsening LV WMSI (hazard ratios, 2.27 [95% CI, 1.69-3.06] and 6.42 [95% CI, 4.94-8.33]) and also of death (hazard ratios, 2.45 [95% CI, 1.62-3.71] and 8.99 [95% CI, 6.3-12.82]) for 1 < LV WMSI < 1.5 and LV WMSI > 1.5, respectively. Both LV WMSI and indexed left atrial volume remained independent predictors in multivariate analysis.

Conclusions: Trypanocidal treatment had no effect on echocardiographic progression of chronic Chagas cardiomyopathy over 5.4 years. Despite normal global LV systolic function, regional wall motion abnormalities and indexed left atrial volume identified patients at higher risk for hard adverse clinical outcomes.

Keywords: Chagas cardiomyopathy; Echocardiography; Prognosis; Trypanocidal therapy.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Chagas Cardiomyopathy / diagnosis
  • Chagas Cardiomyopathy / drug therapy*
  • Chagas Cardiomyopathy / physiopathology
  • Echocardiography / methods*
  • Female
  • Follow-Up Studies
  • Heart Atria / diagnostic imaging*
  • Heart Atria / drug effects
  • Heart Atria / physiopathology
  • Heart Ventricles / diagnostic imaging*
  • Heart Ventricles / drug effects
  • Heart Ventricles / physiopathology
  • Humans
  • Male
  • Middle Aged
  • Nitroreductases / therapeutic use*
  • Prognosis
  • Prospective Studies
  • Stroke Volume / drug effects
  • Stroke Volume / physiology
  • Systole
  • Time Factors
  • Trypanocidal Agents / therapeutic use
  • Ventricular Function, Left / drug effects
  • Ventricular Function, Left / physiology*
  • Young Adult

Substances

  • Trypanocidal Agents
  • aromatic NADH-dependent nitroreductase
  • Nitroreductases