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Right ventricular diastolic relaxation in conscious dog models of pressure overload, volume overload, and ischemia
- Source :
- The Journal of Thoracic and Cardiovascular Surgery. 124(5):964-972
- Publication Year :
- 2002
- Publisher :
- Elsevier BV, 2002.
-
Abstract
- Objective: Limitations in clinical understanding of right ventricular relaxation can be attributed to the paucity of information from basic studies in animal models of right ventricular disease. This study examined, in the conscious state, right ventricular relaxation dynamics under normal conditions (n = 15) and in subacute (2-5 weeks) canine models of right ventricular pressure overload (n = 6), volume overload (n = 7), and free wall ischemia (n = 7). Methods: Right-heart micromanometric measurements were obtained by using multisensor catheters. A new algorithm was developed to obtain representative ensemble averages of hemodynamic waveform data sets. Right ventricular relaxation was analyzed by using an exponential model with 3 parameters: P 0 , τ, and P b . Significant changes versus control values were determined by means of analysis of variance and the Student unpaired t test with Bonferroni's adjustment. Results: In the state of pressure overload, right ventricular pressure decay exhibits an increased P 0 (56.2 ± 19.1 vs 13.1 ± 5.1 mm Hg [mean ± SD]) and prolonged τ (57.1 ± 2.8 vs 27.8 ± 3.9 ms); there is also a decreased P b (−7.9 ± 1.5 vs 0.28 ± 1.8 mm Hg). The only significant change in volume overload is an increased asymptote, P b (5.3 ± 2.9 mm Hg). In right ventricular ischemia, prolongation of τ (41.4 ± 13.0 ms) and decreased P b (−1.95 ± 1.1 mm Hg) attain high significance. Conclusions: Distinctive abnormalities in right ventricular relaxation dynamics accompany pressure overload, volume overload, and ischemia and may contribute to clinical right ventricular dysfunction. J Thorac Cardiovasc Surg 2002;124:964-72
- Subjects :
- Pulmonary and Respiratory Medicine
medicine.medical_specialty
Consciousness
Systole
Heart Ventricles
Muscle Relaxation
Ventricular Dysfunction, Right
Volume overload
Diastole
Myocardial Ischemia
030204 cardiovascular system & hematology
Article
03 medical and health sciences
0302 clinical medicine
Dogs
Internal medicine
medicine
Ventricular Pressure
Animals
030304 developmental biology
Pressure overload
0303 health sciences
business.industry
Models, Cardiovascular
Stroke Volume
Stroke volume
medicine.disease
Disease Models, Animal
Muscle relaxation
Heart failure
Ventricular pressure
Cardiology
Surgery
business
Cardiology and Cardiovascular Medicine
Subjects
Details
- ISSN :
- 00225223
- Volume :
- 124
- Issue :
- 5
- Database :
- OpenAIRE
- Journal :
- The Journal of Thoracic and Cardiovascular Surgery
- Accession number :
- edsair.doi.dedup.....b26c4c9408a00750704f47d7f4675bbc
- Full Text :
- https://doi.org/10.1067/mtc.2002.126677