Double cardiomyoplasty: acute versus chronic results

Area of Science:

• Cardiovascular Surgery
• Surgical Innovation
• Cardiac Physiology

Background:

• Previous studies demonstrated acute double cardiomyoplasty using latissimus dorsi muscles improved cardiac output and pressures.
• Muscle conditioning is crucial for flap viability and function in cardiomyoplasty procedures.

Purpose of the Study:

• To evaluate the hemodynamic effects of double cardiomyoplasty using conditioned latissimus dorsi muscle flaps in dogs.
• To compare the functional outcomes of conditioned versus unconditioned muscle flaps in a cardiac surgery model.

Main Methods:

• Ten dogs underwent double cardiomyoplasty with latissimus dorsi muscle flaps.
• Seven dogs completed an 8-week muscle conditioning period post-surgery.
• Hemodynamic parameters were measured before and after conditioning, and during individual and bilateral muscle stimulation.

Main Results:

• Conditioned muscle flaps failed to contract in 2 out of 7 dogs.
• In the remaining 5 dogs, cardiac output and stroke volume decreased, while peak left ventricular pressure showed a non-significant increase.
• Peak right ventricular pressure significantly increased by 31.3% (p < 0.05) after conditioning.
• Bilateral muscle stimulation resulted in a greater percentage increase in peak right ventricular pressure compared to individual muscle stimulation (p < 0.05).

Conclusions:

• Double cardiomyoplasty with conditioned latissimus dorsi muscle flaps leads to reduced cardiac output and stroke volume.
• Conditioned muscle flaps can significantly increase peak right ventricular pressure.
• The functional capacity of conditioned muscle flaps for cardiac support requires further investigation.