Mapping arrhythmias in the failing heart: from Langendorff to patient

Joseph G. Akar, Fadi G. Akar

Research output: Contribution to journalArticle

Abstract

Sudden cardiac death due to ventricular arrhythmias is a major cause of mortality in patients with heart failure (HF). As HF develops, a host of changes occur at multiple levels, spanning the spectrum from subcellular/molecular to organ-system levels. These changes, collectively referred to as "cardiac remodeling," predispose to electrical disturbances via multiple mechanisms. In humans, most arrhythmias are reentrant by nature, involving circulatory wavefront(s) that excite the heart in rapid, irregular succession. Hence, by definition, reentrant excitation occurs at the multicellular intact tissue level, and therefore, a complete understanding of its dynamics and underlying mechanisms requires investigation of electrophysiological properties (such as action potentials and calcium transients) in intact tissue preparations where cells are electrically coupled to one another. While molecular and cellular studies are critical for identifying changes in individual myocytes, only recently have we begun to understand how these complex changes can create an environment ripe for arrhythmias. In particular, the integrative technique of optical action potential mapping was used in recent years to address key questions regarding changes in network electrical properties of the failing myocardium. In the present manuscript, we review recent findings from mapping studies in the experimental laboratory as they relate to the characterization of the arrhythmic substrate of the failing heart, followed by a discussion of clinical mapping approaches used to identify key characteristics of atrial and ventricular arrhythmias in patients with HF.

Original languageEnglish (US)
JournalJournal of Electrocardiology
Volume39
Issue number4 SUPPL.
DOIs
StatePublished - Oct 2006

Fingerprint

Cardiac Arrhythmias
Heart Failure
Voltage-Sensitive Dye Imaging
Manuscripts
Sudden Cardiac Death
Muscle Cells
Action Potentials
Myocardium
Calcium
Mortality

Keywords

  • Arrhythmias
  • Gap junctions
  • Heart failure
  • Radiofrequency ablation
  • Repolarization

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine

Cite this

Mapping arrhythmias in the failing heart : from Langendorff to patient. / Akar, Joseph G.; Akar, Fadi G.

In: Journal of Electrocardiology, Vol. 39, No. 4 SUPPL., 10.2006.

Research output: Contribution to journalArticle

Akar, Joseph G. ; Akar, Fadi G. / Mapping arrhythmias in the failing heart : from Langendorff to patient. In: Journal of Electrocardiology. 2006 ; Vol. 39, No. 4 SUPPL.
@article{c8e2859c437042fa911601adb3f3ae4e,
title = "Mapping arrhythmias in the failing heart: from Langendorff to patient",
abstract = "Sudden cardiac death due to ventricular arrhythmias is a major cause of mortality in patients with heart failure (HF). As HF develops, a host of changes occur at multiple levels, spanning the spectrum from subcellular/molecular to organ-system levels. These changes, collectively referred to as {"}cardiac remodeling,{"} predispose to electrical disturbances via multiple mechanisms. In humans, most arrhythmias are reentrant by nature, involving circulatory wavefront(s) that excite the heart in rapid, irregular succession. Hence, by definition, reentrant excitation occurs at the multicellular intact tissue level, and therefore, a complete understanding of its dynamics and underlying mechanisms requires investigation of electrophysiological properties (such as action potentials and calcium transients) in intact tissue preparations where cells are electrically coupled to one another. While molecular and cellular studies are critical for identifying changes in individual myocytes, only recently have we begun to understand how these complex changes can create an environment ripe for arrhythmias. In particular, the integrative technique of optical action potential mapping was used in recent years to address key questions regarding changes in network electrical properties of the failing myocardium. In the present manuscript, we review recent findings from mapping studies in the experimental laboratory as they relate to the characterization of the arrhythmic substrate of the failing heart, followed by a discussion of clinical mapping approaches used to identify key characteristics of atrial and ventricular arrhythmias in patients with HF.",
keywords = "Arrhythmias, Gap junctions, Heart failure, Radiofrequency ablation, Repolarization",
author = "Akar, {Joseph G.} and Akar, {Fadi G.}",
year = "2006",
month = "10",
doi = "10.1016/j.jelectrocard.2006.03.011",
language = "English (US)",
volume = "39",
journal = "Journal of Electrocardiology",
issn = "0022-0736",
publisher = "Churchill Livingstone",
number = "4 SUPPL.",

}

TY - JOUR

T1 - Mapping arrhythmias in the failing heart

T2 - from Langendorff to patient

AU - Akar, Joseph G.

AU - Akar, Fadi G.

PY - 2006/10

Y1 - 2006/10

N2 - Sudden cardiac death due to ventricular arrhythmias is a major cause of mortality in patients with heart failure (HF). As HF develops, a host of changes occur at multiple levels, spanning the spectrum from subcellular/molecular to organ-system levels. These changes, collectively referred to as "cardiac remodeling," predispose to electrical disturbances via multiple mechanisms. In humans, most arrhythmias are reentrant by nature, involving circulatory wavefront(s) that excite the heart in rapid, irregular succession. Hence, by definition, reentrant excitation occurs at the multicellular intact tissue level, and therefore, a complete understanding of its dynamics and underlying mechanisms requires investigation of electrophysiological properties (such as action potentials and calcium transients) in intact tissue preparations where cells are electrically coupled to one another. While molecular and cellular studies are critical for identifying changes in individual myocytes, only recently have we begun to understand how these complex changes can create an environment ripe for arrhythmias. In particular, the integrative technique of optical action potential mapping was used in recent years to address key questions regarding changes in network electrical properties of the failing myocardium. In the present manuscript, we review recent findings from mapping studies in the experimental laboratory as they relate to the characterization of the arrhythmic substrate of the failing heart, followed by a discussion of clinical mapping approaches used to identify key characteristics of atrial and ventricular arrhythmias in patients with HF.

AB - Sudden cardiac death due to ventricular arrhythmias is a major cause of mortality in patients with heart failure (HF). As HF develops, a host of changes occur at multiple levels, spanning the spectrum from subcellular/molecular to organ-system levels. These changes, collectively referred to as "cardiac remodeling," predispose to electrical disturbances via multiple mechanisms. In humans, most arrhythmias are reentrant by nature, involving circulatory wavefront(s) that excite the heart in rapid, irregular succession. Hence, by definition, reentrant excitation occurs at the multicellular intact tissue level, and therefore, a complete understanding of its dynamics and underlying mechanisms requires investigation of electrophysiological properties (such as action potentials and calcium transients) in intact tissue preparations where cells are electrically coupled to one another. While molecular and cellular studies are critical for identifying changes in individual myocytes, only recently have we begun to understand how these complex changes can create an environment ripe for arrhythmias. In particular, the integrative technique of optical action potential mapping was used in recent years to address key questions regarding changes in network electrical properties of the failing myocardium. In the present manuscript, we review recent findings from mapping studies in the experimental laboratory as they relate to the characterization of the arrhythmic substrate of the failing heart, followed by a discussion of clinical mapping approaches used to identify key characteristics of atrial and ventricular arrhythmias in patients with HF.

KW - Arrhythmias

KW - Gap junctions

KW - Heart failure

KW - Radiofrequency ablation

KW - Repolarization

UR - http://www.scopus.com/inward/record.url?scp=33749047247&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33749047247&partnerID=8YFLogxK

U2 - 10.1016/j.jelectrocard.2006.03.011

DO - 10.1016/j.jelectrocard.2006.03.011

M3 - Article

C2 - 16920143

AN - SCOPUS:33749047247

VL - 39

JO - Journal of Electrocardiology

JF - Journal of Electrocardiology

SN - 0022-0736

IS - 4 SUPPL.

ER -