Diagnostic performance of echocardiography to predict cardiac tamponade after cardiac surgery.

OBJECTIVES: Cardiac tamponade is a life-threatening complication after cardiac surgery. Echocardiography, both transthoracic (TTE) and transesophageal (TEE), may help to identify cardiac tamponade after surgery, but its diagnostic value remains unverified after cardiac surgery. METHODS: This retrospective single-centre cohort study used the electronic medical record and echocardiography database of the Catharina Hospital Eindhoven, a tertiary referral cardiothoracic centre, to identify patients who received echocardiography because they were clinically suspected of having cardiac tamponade within the 4 weeks after cardiac surgery. Overall diagnostic accuracy of both TTE and TEE was calculated (sensitivity, specificity, positive predictive value, negative predictive value, and receiver operation characteristics curves). Subgroup analyses were performed based on the timing of the echocardiography after primary surgery (<24, 24-72, >72 h). RESULTS: The query identified 427 echocardiographs, 373 TTEs and 54 TEEs, being performed in 414 patients (65% males, mean age 67 years). Of them, 116 patients underwent surgical re-exploration in which a cardiac tamponade was determined in 105 patients with a 30-day mortality of 8.6%. The area under the receiver operation characteristics curve for echocardiography in the 4 weeks after cardiac surgery was 0.78 [95% confidence interval (CI): 0.72-0.84, P < 0.001]. In the first 24 h after surgery was the positive predictive value of echocardiography 58.3% (95% CI: 28.6-83.5) with an area under the curve of 0.64 (95% CI: 0.49-0.80, P = 0.06). The diagnostic accuracy improved over time for both TTE and TEE. CONCLUSIONS: Diagnostic accuracy of echocardiography in the 4 weeks after cardiac surgery for cardiac tamponade is acceptable and improves over time. However, in the early postoperative phase (<24 h), the diagnostic accuracy of echocardiography is poor.

Influence of introduction of positron emission tomography on adherence to mediastinal staging protocols and performance of mediastinoscopy.

PURPOSE: In this study, we investigated the impact of implementation of [(18)F] fluorodeoxyglucose positron emission tomography (FDG-PET) in daily practice on adherence to mediastinal staging protocols and performance of mediastinoscopy in non-small-cell lung cancer (NSCLC) patients who are possible candidates for surgical resection. Institutional review board approval was obtained. PATIENTS AND METHODS: From a nonuniversity teaching hospital and three surrounding community hospitals in Eindhoven, the Netherlands, we studied data from 143 patients with NSCLC who underwent mediastinoscopy and/or thoracotomy in three consecutive periods (1, 0 to 9 months; 2, 10 to 18 months; and 3, 19 to 31 months) after introduction of PET. Mediastinoscopy was indicated in case of enlarged and/or PET-positive nodes. Adherence to these surgical mediastinal staging guidelines and the performance of PET and mediastinoscopy were investigated and compared between the three periods and with our previous study before introduction of PET. RESULTS AND CONCLUSION: Guidelines for indicating mediastinoscopy were adequately followed in significantly more instances after introduction of PET (80%), compared with the period before PET (66%). Optimal yield (lymph node stations 4, right and left, and 7) of mediastinoscopy (in 27% of patients) was not significantly different from the period before PET (39% of patients). Compared with the historical data, the percentage of positive mediastinoscopies increased from 15.5 to 17.6 (not significant). We found no significant differences between the three consecutive periods with regard to adequacy of indicating and performance of mediastinoscopy. After introduction of PET, adherence to staging guidelines with respect to mediastinoscopy improved. Although fewer mediastinoscopies had an optimal yield, more proved to be positive for metastases. Nevertheless, when a mediastinoscopy is indicated, surgeons must be encouraged to reach an optimal yield because PET positive nodes might be false negative. This occurred in 5% to 6% of all patients.