QRS complex changes in the V5 ECG lead during cardiac surgery
H Tsuda1, H Tobata, S Watanabe
1Department of Anesthesiology, Kurume University School of Medicine, Fukuoka, Japan.
Journal of Cardiothoracic and Vascular Anesthesia
|December 1, 1992
Summary
Monitoring R wave amplitude in lead V5 during cardiac surgery helps assess left ventricular free wall recovery. Poorer R wave recovery in coronary artery disease patients and nonsurvivors highlights its prognostic value.
Area of Science:
- Cardiology
- Cardiac Surgery
- Electrophysiology
Background:
- The QRS complex in lead V5 reflects left ventricular (LV) free wall activation.
- Changes in the QRS complex during cardiac surgery can indicate myocardial stress and recovery.
Purpose of the Study:
- To investigate the changes in R wave amplitude of the QRS complex in lead V5 during cardiac surgery.
- To correlate these changes with patient outcomes and underlying cardiac conditions.
Main Methods:
- Continuous monitoring of the QRS complex in lead V5 during cardiac surgery.
- Analysis of R wave amplitude changes from pre-anesthesia through cardiopulmonary bypass (CPB) and sternal closure.
- Comparison of R wave recovery between patients with coronary artery disease and valvular heart disease, and between survivors and nonsurvivors.
Main Results:
- R wave amplitude significantly decreased after anesthesia induction and before CPB (P < 0.001).
- QRS configuration changed post-cardioversion and aortic declamping, with gradual R wave recovery.
- Patients with coronary artery disease showed poorer R wave recovery compared to valvular heart disease patients (P < 0.05).
- Nonsurvivors exhibited significantly smaller R waves than survivors (P < 0.001).
Conclusions:
- R wave amplitude monitoring in lead V5 is crucial for assessing LV free wall electrophysiologic recovery during cardiac surgery.
- Changes in R wave amplitude can detect regional ischemia and predict patient outcomes.
- The findings emphasize the importance of monitoring QRS complex changes, particularly during weaning from CPB.
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