A case of long-acting heart ventricle tachycardia which recognized a slow conduction site with a stimulus in sinus rhythm.

Slow conduction velocities play a role in pulsus alternans and digitalis intoxication and possibly in the arrhythmia due to a rapidly discharging atrial aconitine focus. In the ventricle mephentermine increases conduction velocity, shortens refractory period and A-V conduction time. The present study investigates the usefulness of mephentermine in these conditions. Pulsus alternans was reverted to a normal series of mechanical contractions by mephentermine. The same agent provided periods of regular rhythm during the presence of an atrial aconitine focus; in two cases a permanent sinus rhythm was established. The prolonged P-R interval due to intoxication with acetyl strophanthidin was restored to normal by mephentermine. The action of mephentermine is specific since compounds with addition or subtraction of one methyl group or the hydroxy-mephentermine were ineffective against a circus flutter.

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Autoradiographic distribution in rat tissues of binding sites for endothelin: a neuropeptide?

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1989.256.4.r858 ◽

1989 ◽

Vol 256 (4) ◽

pp. R858-R866 ◽

Cited By ~ 18

Author(s):

C. Koseki ◽

M. Imai ◽

Y. Hirata ◽

M. Yanagisawa ◽

T. Masaki

Keyword(s):

Binding Sites ◽

Rat Tissues ◽

Binding Assays ◽

Heart Ventricle ◽

High Affinity ◽

Long Acting ◽

Porcine Endothelial Cells ◽

Vasoconstrictor Peptide ◽

The Brain

Endothelin (ET) is a potent and long-acting vasoconstrictor peptide consisting of 21 amino acids and recently isolated from a medium of cultured porcine endothelial cells. To determine the possible sites of ET action, we have conducted autoradiography and receptor binding assays with 125I-labeled ET in rat tissues. The displaceable binding sites of the ligand were widely distributed, not only in the arteries and heart but also in various other organs, e.g., brain, kidney, lung, adrenal gland, and intestine. The systemically injected ET did not cross the blood-brain barrier, whereas the ligand, applied in vitro, was mainly located in the hypothalamic and thalamic areas, lateral ventricular region, subfornical organ, globus pallidus, and caudate putamen. Both membrane preparations from the brain stem including diencephalon and from the heart ventricle had similar, specific, and high-affinity binding sites for 125I-ET. We suggest that ET is involved in the regulation of a large variety of organ functions and may also act as a neuropeptide.

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A Patchwork Inverse Method in Combination with the Activation Time Gradient to Detect Regions of Slow Conduction in Sinus Rhythm

2020 Computing in Cardiology Conference (CinC) ◽

10.22489/cinc.2020.108 ◽

2020 ◽

Author(s):

Oumayma Bouhamama ◽

Mark Potse ◽

Remi Dubois ◽

Lisl Weynans ◽

Laura Bear

Keyword(s):

Sinus Rhythm ◽

Inverse Method ◽

Activation Time ◽

Slow Conduction

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Comparative efficacy of short-acting and long-acting quinidine for maintenance of sinus rhythm after electrical conversion of atrial fibrillation.

Heart ◽

10.1136/hrt.38.4.381 ◽

1976 ◽

Vol 38 (4) ◽

pp. 381-387 ◽

Cited By ~ 13

Author(s):

J P Normand ◽

M Legendre ◽

J C Kahn ◽

J P Bourdarias ◽

A Mathivat

Keyword(s):

Atrial Fibrillation ◽

Sinus Rhythm ◽

Comparative Efficacy ◽

Short Acting ◽

Long Acting

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Ventricular Tachycardia With Participation of the Left Bundle-Purkinje System in Patients With Structural Heart Disease: Identification of Slow Conduction During Sinus Rhythm

Journal of Cardiovascular Electrophysiology ◽

10.1111/j.1540-8167.2007.00880.x ◽

2007 ◽

Vol 18 (8) ◽

pp. 808-817 ◽

Cited By ~ 10

Author(s):

CHRISTOPHER REITHMANN ◽

ANTON HAHNEFELD ◽

THOMAS REMP ◽

GERHARD STEINBECK

Keyword(s):

Heart Disease ◽

Ventricular Tachycardia ◽

Sinus Rhythm ◽

Structural Heart Disease ◽

Purkinje System ◽

Disease Identification ◽

Slow Conduction

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A new approach to atrial flutter ablation using functional substrate mapping with wavefront discontinuity during sinus rhythm

EP Europace ◽

10.1093/europace/euab116.099 ◽

2021 ◽

Vol 23 (Supplement_3) ◽

Author(s):

D Valbom Mesquita ◽

L Parreira ◽

J Farinha ◽

R Marinheiro ◽

P Amador ◽

...

Keyword(s):

Sinus Rhythm ◽

Atrial Flutter ◽

Small Area ◽

Low Voltage ◽

Categorical Variables ◽

Accurate Identification ◽

Funding Sources ◽

Slow Conduction ◽

Voltage Mapping ◽

Conduction Zone

Abstract Funding Acknowledgements Type of funding sources: None. Background Ultra high-density (UHD) mapping allows accurate identification of local abnormal electrograms and low voltage within a small area range, allowing precise identification of reentry circuits. Areas with high isochronal density in a small area known as deceleration zones (DZ) are responsible for reentry. Purpose Identify the DZ and areas of low voltage in sinus rhythm (SR) and evaluate the feasibility of performing atrial flutter (AFL) ablation by targeting those zones. Methods We prospectively enrolled patients in SR referred for AFL ablation (either typical or atypical). An isochronal late activation mapping (ILAM) during SR with UHD catheter was performed, annotating latest deflection of local electrograms. DZ were defined as areas with >3 isochrones within 1cm radius, prioritizing zones with maximal density. Atrial flutter was then induced and ILAM during flutter was performed for comparison. Voltage mapping was also assessed (0.1-0.5mV). Ablation targeted DZ in SR that displayed the higher voltage. DZ in SR were compared to DZ in AFL. Number of radiofrequency (RF) applications needed to terminate AFL were assessed. After AFL termination, complete line of the slow conduction zone was completed, and pulmonary vein isolation (PVI) was done in case of left AFL. Categorical variables are presented in absolute and relative values and median and interquartile range were used for numerical variables, as well t-student test for correlation of numerical variables. Results We studied 6 AFL (4 atypical, 66.7%) in 5 patients, 2 male (40%), median age 70 (64- 72). UHD ILAM in SR with 2195 points (1212-2865) and 2197 points (1356-3102) in AFL (p = 0.62). The UHD ILAM identified a median of (QR) DZ in SR, that colocalized with AFL isthmus and DZ in AFL in 100%. DZ were not always located in low voltage areas. Aiming at the higher voltage in the DZ terminated the AFL in all cases, with a median RF time of 38 (25-58) seconds and AFL was no longer inducible. However, according to protocol, the complete line of slow conduction zone was done, with a median RF time of 1049.5 (274-1194) seconds (p = 0,009). Conclusions Isochronal mapping in sinus rhythm with UHD catheters can display the functional substrate for reentry in AFL, allowing a substrate guided ablation in case of non-inducible AFL. Targeting the areas of high isochronal density, is effective in terminating AFL, obviating the need for extensive ablation. Abstract Figure.

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