Evaluation of Electrocardiogram Parameters and Heart Rate Variability During Blood Pressure Elevation by Phenylephrine in Cirrhotic Rats.
Cardiovasc Toxicol
; 24(3): 321-334, 2024 Mar.
Article
in En
| MEDLINE
| ID: mdl-38409566
ABSTRACT
Cirrhotic cardiomyopathy is a myocardial disease that may go undetected in the early stages due to peripheral vasodilatation. The aim of the study was to evaluate the electrocardiogram (ECG) and heart rate variability (HRV) after raising blood pressure by phenylephrine injection in rats with liver cirrhosis. Twenty male Sprague-Dawley rats were divided into the Sham and common bile duct ligation (CBDL) groups. After 44 days, animals were anesthetized and the right femoral artery and vein catheterized. After a steady-state period, a bolus injection of phenylephrine (PHE, 10 µg/µl/IV, baroreflex maneuver) was followed by a slow injection of PHE (100 µg/ml/5 min/IV, sustained maneuver). Rapid and slow injections of PHE resulted in a greater increase in mean arterial pressure (MAP) and a weaker bradycardia response in the CBDL group than in the Sham group. ECG analysis showed increased QT, QTc, JT, and T peak to T end in the CBDL group, which remained unchanged after PHE injection. On the other hand, the parasympathetic indices of the HF band and RMSSD, and the sympathetic index of the LF band after PHE injection were lower in the CBDL group than in the Sham group.ECG data indicated prolonged ventricular depolarization and repolarization, independent of blood pressure levels in cirrhosis. On the other hand, after PHE injection, the parasympathetic and sympathetic components of HRV decreased, regardless of the duration of elevated blood pressure. We suggest that HRV analysis can provide a useful approach to assess cardiac dysfunction associated with elevated blood pressure in cirrhosis.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Hypertension
Limits:
Animals
Language:
En
Journal:
Cardiovasc Toxicol
Journal subject:
ANGIOLOGIA
/
CARDIOLOGIA
/
TOXICOLOGIA
Year:
2024
Document type:
Article
Affiliation country:
Irán