Background & Aims: The most common diagnostic modality for pulmonary emboli is CT angiography (CTA). Because of the availability and inexpensiveness, taking an electrocardiogram (ECG) is the first step in patients suspicious to pulmonary emboli. However, ECG does not provide any sensitive or specific manifestations for diagnosis of pulmonary emboli. We aim to evaluate the correlation between severity of pulmonary emboli in CTA and ECG changes.

 Materials & Methods: In this study, 102 patients diagnosed with massive or submassive pulmonary emboli due to Qanadli index in CTA studies were evaluated. ECG was taking in all patients. There are 35 previously reported pathologic changes in ECG which were all evaluated in these patients. The correlation between ECG findings and pulmonary emboli severity in CTA was evaluated.

 Results: Massive emboli were present in 56.9% and submassive emboli in 43.1% of cases. In 76.5% of cases, pathologic changes in ECG considering emboli were present. In cases with massive emboli compared to submassive emboli, ECG changes (86.2% vs. 63.6%) and mean pathologic findings in ECG (5.82±2.95 vs. 4.25±2.84) were significantly higher. Prevalence of S1O3T3, S1&SaVL>1.5 mm, ST depression in V₁-V₃, ST elevation in V1-V3, Negative T wave in V₁-V₃, Right axis deviation, RVH criteria, P-pulmonale, QR pattern in V1 were significantly higher in massive emboli group.

 Conclusion: ECG changes and number of pathologic findings were higher in massive emboli group. Most significant changes were negative T and ST depression or elevation in V1-V3 and right heart involvement findings and could predict severity of pulmonary emboli.

  SOURCE: URMIA MED J 2015: 26(2): 165 ISSN: 1027-3727