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Updated: Aug 19, 2026
Ascending Aortic Constriction in Rats for Creation of Pressure Overload Cardiac Hypertrophy Model
Published on: June 29, 2014
Effects of cardiomyoplasty on cardiac growth in rats
C A van Doorn1, M S Bhabra, R M el Oakley
1Department of Cardiothoracic Surgery, Wythenshawe Hospital, Manchester, United Kingdom.
Insights
Cardiomyoplasty (CMP) in juvenile rats did not further restrict cardiac growth beyond general surgical effects. Further studies on stimulated muscle wraps are needed before pediatric CMP application.
Area of Science:
- Pediatric cardiology
- Surgical innovation
- Animal models in research
Background:
- Cardiomyoplasty (CMP) is a proposed treatment for pediatric patients.
- Concerns exist regarding potential cardiac growth restriction from the muscle wrap in CMP.
- This study investigates the impact of CMP on cardiac development in an immature animal model.
Purpose of the Study:
- To investigate the potential for cardiac growth restriction caused by cardiomyoplasty (CMP) in a juvenile animal model.
- To assess the impact of CMP on cardiac development compared to sham surgery and controls.
- To evaluate the safety and feasibility of CMP in immature subjects.
Main Methods:
- Six-week-old rats underwent either CMP with left thoracotomy or thoracotomy alone (sham).
- A control group received no surgery.
- Measurements were taken 20 weeks post-surgery after body weight stabilization.
Main Results:
- Surgical procedures, including CMP, resulted in significantly reduced overall body weight compared to controls.
- Cardiac ventricular weights in the CMP group were significantly lower than controls but not different from the sham group.
- Left ventricular end-diastolic volumes remained similar across all groups, indicating no additional restriction from CMP.
Conclusions:
- Major surgery in juvenile rats impairs overall growth.
- This study found no evidence that cardiac wrapping in CMP causes additional cardiac development restriction.
- Further research involving stimulated muscle wraps is necessary before considering CMP for pediatric patients.
Background And Aim Of The Study:
Cardiomyoplasty (CMP) has been proposed as a treatment for pediatric patients, but restriction of cardiac growth by the muscle wrap is a potential source of concern. This possibility was investigated in an immature animal model.
Methods:
Six-week-old rats (body weight 203.8 +/- 5.4 g, mean +/- SEM) underwent either left thoracotomy with CMP (group I, n = 7), or thoracotomy without CMP (group II, n = 8). A third group (group III, n = 7) served as untreated controls. Final measurements were made 20 weeks later after body weights had reached a plateau.
Results:
Preoperative body weights were not significantly different between the groups. At elective sacrifice, the body weights of animals that underwent surgery did not differ significantly (group I, 558.0 +/- 21.5 g and group II, 617.3 +/- 20.3 g), but were significantly less than those of control animals (727.6 +/- 13.3 g, p < 0.001 and p < 0.01, respectively). Cardiac ventricular weights in the CMP group were significantly less than those of control animals (group I, 1.21 +/- 0.06 g; group III 1.45 +/- 0.04 g; p < 0.01), but were not statistically different from those of the sham thoracotomy group (group II, 1.36 +/- 0.05 g). Mean left ventricular end-diastolic volumes were similar in all groups (group I, 0.67 +/- 0.07 mL; group II, 0.66 +/- 0.07 mL; and group III, 0.69 +/- 0.10 mL; p = ns).
Conclusions:
A major surgical procedure impairs growth in juvenile rats. no evidence emerged from this study for additional restriction of cardiac development due to cardiac wrapping. However, studies that include stimulated muscle wraps are needed before CMP should be considered for the pediatric age group.
