Relationship of plasma neuropeptide y with angiographic, electrocardiographic and coronary physiology indices of reperfusion during ST elevation myocardial infarction

Objectives: The co-transmitter neuropeptide Y (NPY) is released during high levels of sympathetic stimulation and is a potent vasoconstrictor. We defined the release profile of plasma NPY during acute ST elevation myocardial infarction, and tested the hypothesis that levels correlate with reperfusion measures after treatment with primary percutaneous coronary intervention (PPCI). Design: Prospective observational study. Setting: University hospital heart centre. Patients: 64 patients (62.6±11.7 years-old, 73% male) presenting throughout the 24-h cycle of clinical activity with ST elevation myocardial infarction. Interventions PPCI. Main outcome measures: NPY was measured (ELISA) in peripheral blood taken before and immediately after PPCI and at 6, 24 and 48 h post-PPCI. Reperfusion was assessed by angiographic criteria, ST segment resolution, invasive measurement of coronary flow reserve and the index of microcirculatory resistance. Results: Plasma NPY levels were highest before PPCI (17.4 (8.8-42.2) pg/ml, median (IQR)) and dropped significantly post-PPCI (12.4 (6.5-26.7) pg/ml, p2, n=16) or no electrocardiographic ST resolution (33 also had significantly higher plasma NPY levels pre-PPCI and post-PPCI. Conclusions: Plasma NPY levels correlate with indices of reperfusion and coronary microvascular resistance