Intramyocardial delivery of PDGF with peptide nanofibers reduced infarcted myocardial volume (12.0% vs 34.0% in MI controls; P<0.001) and improved ventricular function without pulmonary toxicity.
RCT (n=127)
blinded
randomized
Does intramyocardial delivery of PDGF-BB with self-assembling peptide nanofibers improve ventricular function without pulmonary toxicity in rats post-myocardial infarction?
Local intramyocardial delivery of PDGF-BB via self-assembling peptide nanofibers improves long-term cardiac performance and reduces infarct size in a rat model of MI without causing pulmonary toxicity.
Absolute Event Rate: 12% vs 34%
p-value: p=<0.001
BACKGROUND: Local delivery methods can target therapies to specific tissues and potentially avoid toxicity to other organs. Platelet-derived growth factor can protect the myocardium, but it also plays an important role in promoting pulmonary hypertension. It is not known whether local myocardial delivery of platelet-derived growth factor during myocardial infarction (MI) can lead to sustained cardiac benefit without causing pulmonary hypertension. METHODS AND RESULTS: We performed a randomized and blinded experiment of 127 rats that survived experimental MI or sham surgery. We delivered platelet-derived growth factor (PDGF)-BB with self-assembling peptide nanofibers (NFs) to provide controlled release within the myocardium. There were 6 groups with n > or = 20 in each group: sham, sham+NF, sham+NF/PDGF, MI, MI+NF, and MI+NF/PDGF. Serial echocardiography from 1 day to 3 months showed significant improvement of ventricular fractional shortening, end-systolic dimension, and end-diastolic dimension with local PDGF delivery (P < 0.05 for MI+NF/PDGF versus MI or MI+NF). Catheterization at 4 months revealed improved ventricular function in the controlled delivery group (left ventricular end-diastolic pressure, cardiac index, +dP/dt, -dP/dt, and time constant of exponential decay all P < 0.05 for MI+NF/P versus MI or MI+NF). Infarcted myocardial volume was reduced by NF/PDGF therapy (34.0 +/- 13.3% in MI, 28.9 +/- 12.9% in MI+NF, and 12.0 +/- 5.8% in MI+NF/PDGF; P < 0.001). There was no evidence of pulmonary toxicity from the therapy, with no differences in right ventricular end-systolic pressure, right ventricular dP/dt, bromodeoxyuridine staining, or pulmonary artery medial wall thickness. CONCLUSIONS: Intramyocardial delivery of PDGF by self-assembling peptide NFs leads to long-term improvement in cardiac performance after experimental infarction without apparent pulmonary toxicity. Local myocardial protection may allow prevention of heart failure without systemic toxicity.
Hsieh et al. (Tue,) conducted a rct in myocardial infarction (n=127). Platelet-derived growth factor (PDGF)-BB with self-assembling peptide nanofibers (NFs) vs. MI alone or MI+NF was evaluated on Infarcted myocardial volume (p=<0.001). Intramyocardial delivery of PDGF with peptide nanofibers reduced infarcted myocardial volume (12.0% vs 34.0% in MI controls; P<0.001) and improved ventricular function without pulmonary toxicity.