What question did this study set out to answer?

The aim is to investigate how mechanical load changes affect the electrophysiological properties of the myocardium, particularly regarding arrhythmias.

September 1, 1996Circulation

Cycle Length Dependence of the Electrophysiological Effects of Increased Load on the Myocardium

View Full Paper

Ask AI

Bookmark

Why the study?

Does transiently increased myocardial load alter action potential duration and electrical restitution in a pig model?

Population

Anesthetized pigs with exposed hearts

Comparison

Transient aortic occlusion vs Normal loading (before aortic occlusion)

Design

Preclinical

Authors

SHS M HornerWhitchurch Hospital DDD J DickNorfolk and Norwich University Hospital CMConrad MurphyCharing Cross Hospital

Discussion

Member takes

Implication

Raises possibility of load-driven proarrhythmia; extends mechanoelectric feedback data but leaves human translation open.

Key Points

The aim is to investigate how mechanical load changes affect the electrophysiological properties of the myocardium, particularly regarding arrhythmias.
Pigs were anesthetized with exposed hearts; a snare was placed around the aorta.
Actions involved pacing the right atrium and recording monophasic action potentials and ventricular pressure during aortic occlusion.
Electrical restitution curves were constructed from data during normal and transient aortic loading.
Action potential duration shortened on aortic occlusion decreased with shorter steady-state intervals (P = .0008).
Increased load resulted in a decrease of 9.4 ms in action potential duration at the plateau of the restitution curve (P < .0001).
Maximum slope of electrical restitution curve increased by 32 ms/100 ms (P = .04) with increased load.

Structured PICO

Does transiently increased myocardial load alter action potential duration and electrical restitution in a pig model?

Population

Anesthetized pigs with exposed hearts

Intervention

Transient aortic occlusion (increased myocardial load)

Comparator

Normal loading (before aortic occlusion)

Outcome

Changes in steady-state action potential duration and electrical restitutionsurrogate

Transiently increased myocardial load alters rate-dependent electrophysiology, including steepening the electrical restitution curve, which may promote arrhythmogenesis through mechanoelectric feedback.

Cite This Study

Horner et al. (1996) studied this question.

synapsesocial.com/papers/6a208e89d763757abeb41a2e https://doi.org/10.1161/01.cir.94.5.1131

View Full Paper

Ask AI

Bookmark

Cycle Length Dependence of the Electrophysiological Effects of Increased Load on the Myocardium

Discussion

Member takes

Implication

Key Points

Structured PICO

Cite This Study

Cycle Length Dependence of the Electrophysiological Effects of Increased Load on the Myocardium

Discussion

Member takes

Implication

Key Points

Structured PICO

Cite This Study

Also Consider

Also Consider