Long-term effects of dynamic aortomyoplasty

Area of Science:

• Cardiovascular Surgery
• Biomedical Engineering
• Regenerative Medicine

Background:

• Aortomyoplasty aims to create diastolic counterpulsation by wrapping the latissimus dorsi muscle (LDM) around the ascending aorta.
• The ascending aorta is intended to function as an ectopic neo-ventricle, compressed during diastole to augment circulation.

Purpose of the Study:

• To evaluate the long-term hemodynamic effects and structural integrity of aortomyoplasty.
• To assess the efficacy of aortomyoplasty in improving myocardial perfusion and cardiac output, particularly during heart failure.

Main Methods:

• The right latissimus dorsi muscle (LDM) was transferred and wrapped around an enlarged ascending aorta in 5 goats.
• Postoperative electrostimulation was applied in a counterpulsating manner, with hemodynamic assessments at 12 and 24 months.
• The subendocardial viability index was calculated in basal conditions and after induced heart failure using propranolol hydrochloride.

Main Results:

• Aortomyoplasty led to significant long-term improvement in the subendocardial viability index, both in basal states and after induced heart failure.
• During induced heart failure, the procedure increased cardiac output and decreased systemic vascular resistance.
• Histopathology confirmed aortic wall integrity, absence of thromboembolism, and stable aortic diameters up to 24 months, with robust LDM-aortic adhesions.

Conclusions:

• Aortomyoplasty effectively provides chronic diastolic augmentation and supports circulation during heart failure.
• The procedure demonstrates long-term preservation of aortic structure and function.
• Aortomyoplasty represents a promising strategy for circulatory support in cardiac conditions.