Noncardioplegic myocardial preservation.

Area of Science:

• Cardiology
• Cardiac Surgery
• Cardiovascular Physiology

Background:

• The optimal method for intraoperative myocardial preservation during cardiac surgery is debated.
• Potassium (K+) cardioplegia is widely used but its efficacy and safety are continually assessed.
• Alternative preservation techniques are explored to minimize myocardial damage.

Purpose of the Study:

• To evaluate the efficacy of cold-blood perfusion without K+ cardioplegia for myocardial preservation.
• To assess ultrastructural changes and cellular damage following this preservation technique.
• To analyze long-term clinical and angiographic outcomes in patients undergoing myocardial revascularization.

Main Methods:

• Description of a cold-blood perfusion technique used in over 3,500 patients since 1975.
• Quantitative ultrastructural analysis of myocardial tissue in four patients before and after cardiopulmonary bypass.
• Clinical and angiographic follow-up for up to 6 years in 157 patients.

Main Results:

• Ultrastructural analysis revealed minimal cellular damage associated with the technique.
• In 100 patients with multiple vessel bypass, graft patency was confirmed, ruling out technical failure.
• Postoperative global left ventricular function remained unchanged in 80% and improved in 19% of patients.
• Left ventricular function deteriorated in only one patient.

Conclusions:

• Intraoperative oxygenation via cold-blood perfusion is a successful and safe method for myocardial preservation.
• This technique demonstrates excellent long-term preservation of left ventricular function.
• Cold-blood perfusion offers a viable alternative to K+ cardioplegia in myocardial revascularization.