Mitigating cardiac dysfunction by TOE-guided cardioplegia and mitral valve repair

Area of Science:

• Cardiovascular Surgery
• Cardiac Anesthesia
• Echocardiography

Background:

• 15-20% of patients develop left ventricular dysfunction post-mitral valve repair despite normal baseline ejection fraction.
• Standard ejection fraction cutoffs have limited sensitivity for early systolic impairment in mitral regurgitation.
• Mitral regurgitation induces mitochondrial oxidative stress, increasing myocardial susceptibility to ischemia-reperfusion injury.

Purpose of the Study:

• To reconcile theories of pre-existing myocardial disease versus suboptimal intraoperative protection.
• To investigate the role of transesophageal echocardiography-guided cardioplegia delivery in mitigating postoperative cardiac dysfunction.
• To emphasize the importance of precise surgical strategies informed by pre-operative assessment.

Main Methods:

• Utilized transesophageal echocardiography (TEE) for guided cardioplegia delivery during mitral valve repair.
• Monitored intramyocardial flow via TEE to ensure adequate subendocardial protection.
• Systematic pre-operative TEE assessment to define mitral regurgitation mechanisms and guide surgical repair.

Main Results:

• Postoperative left ventricular dysfunction is linked to reduced myocardial contractility and stroke volume.
• TEE-guided cardioplegia delivery aims to mitigate myocardial reperfusion injury.
• Mild aortic regurgitation necessitates direct ostia cardioplegia due to left ventricular dilatation and diminished myocardial flow.

Conclusions:

• Optimizing cardioplegia delivery and surgical technique is crucial for preventing myocardial reperfusion injury.
• TEE-guided cardioplegia offers potential benefits for myocardial protection during mitral valve repair.
• Further clinical trials are warranted to establish TEE-guided cardioplegia as a standard surgical practice.