Left ventricular unloading in nonischemic dilated cardiomyopathy improves coronary haemodynamic reserve

Background: The Impella CP is a catheter‐based ventricular assist device used in the management of cardiogenic shock and to support high‐risk percutaneous coronary interventions (PCI). Despite its growing use, the effects of Impella CP on coronary flow dynamics as measured by intracoronary continuous thermodilution have not been fully quantified.

Aims: This study aimed to evaluate the impact of percutaneous ventricular unloading (PVU) with Impella CP on coronary flow reserve (CFR) and microvascular resistance reserve (MRR) in patients with severe nonischemic dilated cardiomyopathy undergoing intracoronary infusion of autologous bone‐marrow derived mononuclear cells (BMMNCs).

Methods: Coronary flow (Q) was assessed using intracoronary continuous thermodilution both at rest (Qrest) and during hyperemia (Qhyper) before and after PVU with the Impella CP. Measurements were performed in the left anterior descending (LAD) artery using a dedicated pressure/thermistor coronary guidewire. CFR and MRR were calculated post‐hoc.

Results: Nine patients underwent investigation with continuous thermodilution. Initiation of LV unloading with Impella CP resulted in a significant increase in CFR (from 2.72 ± 0.76, to 3.9 ± 1.84, p = 0.049) and MRR (from 3.09 ± 0.97, to 4.50 ± 1.93 p = 0.022). A decrease in mean Qrest and an increase in mean Qhyper was also noted.

Conclusions: PVU with Impella CP led to a significant increase CFR and MRR, suggesting an improvement in coronary haemodynamic reserve. Further studies are needed to validate these findings in a larger patient population.

Trial Registration: Clinicaltrials. org: DCM Support NCT03572660.