LVAD Unloading on Ischemic and Nonischemic Cardiomyopathy

The Effect of LVAD Unloading on Cardiac Recovery in Patients with Ischemic and Nonischemic Cardiomyopathy

May 17, 2017

Key Takeaways

  • Myocardial function improvement following mechanical unloading with durable LVADs may occur in patients with chronic ischemic cardiomyopathy, but at a much lower rate than those with nonischemic cardiomyopathy (21% vs 5%).
  • Little is known about the effect of LVADs on myocardial structure and function following treatment for ischemic cardiomyopathy (ICM).
  • Peak LVEF can be achieved 6 months after LVAD support.
  • Patient characteristics dictate the most favorable duration of mechanical unloading in patients with ICM.
  • This study showed that chronic mechanical unloading can improve myocardial structure and function in both nonischemic cardiomyopathy (NICM) and ICM patients.

Left ventricular assist devices (LVADs) have become increasingly prevalent tools used in the treatment of heart failure (HF) patients. Reverse remodeling as well as myocardial function improvement may occur in HF patients receiving LVAD support.

Although previous studies have focused on nonischemic cardiomyopathy (NICM) etiology regarding the results of LVAD therapy for heart function improvement, there is currently little evidence demonstrating the effects of ischemic cardiomyopathy (ICM) on myocardial structure and function following LVAD therapy.

A study from the Journal of the American College of Cardiology evaluated the etiology of ICM HF on heart structure and function improvement in patients receiving LVAD support.1 Examination of heart recovery was performed using transthoracic echocardiograms prior to LVAD implantation and during implantation at 1, 2, 3, 4, 6, 9, and 12 months. To accurately assess the impact LVADs had on heart recovery, patients with acute MI, postcardiotomy cardiogenic shock, and acute myocarditis were excluded.

Figure 1.Cardiac Recovery in ICM and NICM Patients Following LVAD Unloadinga
Cardiac Recovery in ICM and NICM Patients
aData from Wever-Pinzon J, Selzman CH, Stoddard G, et al1

Patients were divided into two groups: ICM and NICM (control). The use of right heart catheterization allowed researchers to identify the sufficiency of LV pressure unloading. Findings showed no significant difference between the two groups in terms of the degree of LV unloading after LVAD implantation.

In the ICM group, LVEF increased from 20% to 24% in 6 months, and LV mass index decreased from 133 g/m2 to 92 g/m2. Overall, 21% of NICM patients and 5% of patients with ICM achieved a LVEF ≥40 with LVAD at 6 months. Thus, researchers concluded that peak LVEF can be achieved 6 months after LVAD support.

References:

  1.  Wever-Pinzon J, Selzman CH, Stoddard G, et al. Impact of Ischemic Heart Failure Etiology on Cardiac Recovery During Mechanical Unloading. J Am Coll Cardiol. . 2016;68(16):1741-1752.

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