Skeletal muscle ventricle aortic counterpulsation: function during chronic heart failure

Area of Science:

• Biomedical Engineering
• Cardiovascular Surgery
• Regenerative Medicine

Background:

• Skeletal muscle ventricles (SMVs) are engineered pumping chambers utilizing latissimus dorsi muscle.
• Previous studies confirmed SMV aortic counterpulsator stability and efficacy in normal canines.
• This research investigates SMV aortic counterpulsator performance in a chronic heart failure model.

Purpose of the Study:

• To evaluate the effectiveness of the SMV aortic counterpulsator in a canine model of chronic heart failure.
• To assess the impact of SMV counterpulsation on hemodynamic parameters in a failing heart.

Main Methods:

• Six dogs underwent creation of pericardium-lined SMVs from latissimus dorsi muscle, with electrical conditioning for fatigue resistance.
• SMVs were connected to the descending thoracic aorta, and rapid ventricular pacing induced chronic heart failure over 7 weeks.
• SMV stimulation during cardiac diastole was performed at a 1:2 to 1:3 ratio.

Main Results:

• SMV contraction increased diastolic pressure time-index by 12.1% at baseline and 33.6% after 7 weeks of heart failure.
• Counterpulsation led to significant afterload reduction, increasing peak left ventricular ejection velocity by 22.7% and stroke volume by 6.2%.
• Coronary blood flow augmentation averaged 47.6% in measurements taken at 7 weeks.

Conclusions:

• The SMV aortic counterpulsator demonstrates significant improvement in cardiac assistance for a failing heart.
• This technology shows promise as a viable option for advanced cardiac support in heart failure patients.