What question did this study set out to answer?

To evaluate the specific role of adrenoceptor subtypes in the development and severity of early ventricular arrhythmias triggered by acute coronary artery occlusion.

July 1, 2002Cardiovascular ResearchOpen Access

Noradrenaline, infused locally, reduces arrhythmia severity during coronary artery occlusion in anaesthetised dogs

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Why the study?

Does intracoronary noradrenaline reduce ventricular arrhythmias during coronary artery occlusion in anaesthetised dogs?

Population

Mongrel dogs anaesthetised with chloralose and urethane undergoing coronary artery occlusion

Comparison

Intracoronary infusion of noradrenaline… vs Intracoronary saline infusion for the same period

Design

Preclinical

Follow-up

25-min occlusion period and following reperfusion

Authors

AVA VéghUniversity of Szeged

Discussion

Member takes

Implication

May attenuate canine reperfusion arrhythmias via alpha-adrenoceptors; leaves open translation to human trials.

Key Points

To evaluate the specific role of adrenoceptor subtypes in the development and severity of early ventricular arrhythmias triggered by acute coronary artery occlusion.
Chloralose- and urethane-anaesthetised mongrel dogs received intracoronary infusions of noradrenaline (100 ng kg⁻¹ min⁻¹), phenylephrine (200 ng kg⁻¹ min⁻¹), isoprenaline (12.5 ng kg⁻¹ min⁻¹), or saline into a branch of the LAD starting 10 min prior to and lasting through a 25-min occlusion.
An additional group received intravenous noradrenaline (1 to 2 µg kg⁻¹ min⁻¹ for 60 min) 24 hours prior to coronary artery occlusion.
Haemodynamics, coronary flow, epicardial ST-segments, electrical inhomogeneity, and incidences of ventricular tachycardia and ventricular fibrillation during occlusion and reperfusion were continuously recorded.
Intracoronary noradrenaline markedly reduced occlusion-induced ventricular arrhythmia severity and increased post-reperfusion survival to 40%, whereas saline controls experienced 0% survival.
Intracoronary phenylephrine also conferred protection by reducing occlusion-induced ventricular fibrillation from 80% in controls to 20% and yielding 42% survival, whereas isoprenaline aggravated arrhythmias (5 of 7 dogs fibrillated within 10 min; 0% survival).
Endogenous noradrenaline release via guanethidine or intravenous noradrenaline pre-treatment 24 hours prior to occlusion significantly reduced electrical inhomogeneity and reperfusion arrhythmias.

Structured PICO

Does intracoronary noradrenaline reduce ventricular arrhythmias during coronary artery occlusion in anaesthetised dogs?

Population

Mongrel dogs anaesthetised with chloralose and urethane undergoing coronary artery occlusion

Intervention

Intracoronary infusion of noradrenaline (100 ng/kg/min), phenylephrine (200 ng/kg/min), or isoprenaline (12.5 ng/kg/min) commencing 10 min prior to occlusion and throughout the 25-min occlusion period; or intravenous noradrenaline (1-2 microg/kg/min) 24 h prior to occlusion

Comparator

Intracoronary saline infusion for the same period

Outcome

Ventricular arrhythmias (ventricular premature beats, tachycardiac episodes, incidence of VT and VF) during occlusion and following reperfusion, and survivalsurrogate

Exogenously administered or endogenously released noradrenaline reduces the severity of ischemia- and reperfusion-induced ventricular arrhythmias in a canine model, likely mediated by alpha-adrenoceptors.

Cite This Study

A Végh (2002) studied this question.

synapsesocial.com/papers/6a6f75e65671bbf00bc29269 https://doi.org/10.1016/s0008-6363(02)00342-5

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Noradrenaline, infused locally, reduces arrhythmia severity during coronary artery occlusion in anaesthetised dogs

Discussion

Member takes

Implication

Key Points

Structured PICO

Cite This Study

Noradrenaline, infused locally, reduces arrhythmia severity during coronary artery occlusion in anaesthetised dogs

Discussion

Member takes

Implication

Key Points

Structured PICO

Cite This Study

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