Right ventricular echocardiographic predictors of postoperative supraventricular arrhythmias after thoracic surgery: a pilot study.

BACKGROUND

We used echocardiographically derived myocardial performance index (MPI) to assess changes in global right ventricular function with lung isolation. We hypothesized that changes in MPI with lung isolation may be related to the incidence of postoperative supraventricular tachycardia (SVT).

METHODS

Transesophageal echocardiographic examinations were performed after induction of general anesthesia in patients undergoing elective lung resections. Doppler tissue imaging was used to calculate MPI at baseline and 10 minutes after institution of one-lung ventilation (OLV). Arrhythmias occurring within the first 5 postoperative days were recorded.

RESULTS

Fifty-nine patients completed the study. Nineteen of 59 patients with a normal baseline MPI (<0.40) had a higher incidence of SVT as compared with patients with an abnormal baseline MPI (42% versus 10%; p = 0.012). The MPI worsened during OLV in 46 patients; a worsening of MPI with lung isolation that was normal at baseline was associated with higher incidence of SVT (57% versus 0%; p = 0.045) compared with a worsening of MPI in patients with an abnormal baseline MPI (13% versus 6%; p = 0.62). A normal baseline MPI value that worsened after OLV, left atrial dilation, and advanced age were identified as predictors of postoperative SVT.

CONCLUSIONS

Lung isolation is associated with acute changes in global right ventricular function. A normal baseline MPI that worsens after lung isolation is a better predictor of postoperative SVT as compared with baseline abnormal MPI that does not worsen after lung isolation. Myocardial performance index has a potential to be used as a right ventricular stress test to tolerate OLV before thoracic surgery.