Heart Failure Implant Therapy Shows Early Promise, but Skepticism Remains
At the HFSA annual meeting, researchers presented early evidence on cardiac microcurrent therapy for heart failure, including a post hoc analysis of the C-MIC II trial. The analysis showed better exercise capacity measures with the implant than in controls, though one discussant called the magnitude of benefit hard to believe. The therapy is designed to alter electrical fields and fibroblast activity, and investigators said larger randomized trials are needed.
At the HFSA meeting, researchers rechecked six-month exercise-test data from C-MIC II using a masked central laboratory. The implant group outperformed controls on peak metabolic equivalents and percent-predicted peak oxygen uptake, but the absolute peak oxygen uptake difference fell short of significance.
C-MIC II originally randomized 65 people with hard-to-treat, non-ischemic heart failure with reduced ejection fraction and used a surgically placed epicardial device. One discussant doubted the size of the benefit, and investigators called for bigger randomized trials. A newer under-the-skin version, tested in C-MIC III, puts the generator and lead beneath the skin and can be implanted by a heart rhythm specialist in the catheterization laboratory.
If validated, cardiac microcurrent therapy could offer another option for people with refractory heart failure, a group with limited treatments and substantial symptom burden. A subcutaneous implant may be easier to place than a surgical epicardial device, potentially broadening access to less stable patients. Yet uncertain effect sizes and the need for larger randomized trials may temper adoption. Patients, clinicians, and device developers could face decisions about waiting for stronger evidence versus pursuing early experimental care.