Troponin Release in Acute Pulmonary Embolism Correlates to Increased Right Heart Volumes on CT Pulmonary Angiography

Purpose: The release of troponin in patients with acute Pulmonary Embolism (PE) is assumed secondary to elevated intra-cardiac chambers` pressure. As the pressure is correlated with the dimensions of the heart, we hypothesized that troponin levels will raise as the right sided cardiac chambers` volumes enlarge.

Our study aim is to investigate the association between the volumes based on CT pulmonary angiography (CTPA) with cardiac troponin levels.

Methods: Patients who underwent CTPA and had a troponin test performed within 72 hours of the CTPA were included, and grouped by gender. Using automated software, the volumes of the four cardiac chambers indexed to body surface index (BSA) were calculated, and correlated to troponin after adjustment to age and creatinine clearance.

Results: The final cohort consisted of 183 patients` of whom 81 male patients.
Patients with troponin level at the upper tertile compared to the lower tertile, had larger volumes of their RV and RA:
RV volumes in females, 80.8 (milliliters/m²) vs. 50 P<0.001; males 79.8 vs. 62.0, P=0.005.RA volumes: females 64.5 vs. 40.3, P=0.001; males 53.4, vs. 42.3, P=0.044). Results were also significant when for comparison between the middle tertile of troponin level to the lower tertile.

Conclusion: This is the first study to show the association between increased volumes of both the RA and the RV, and elevated troponin levels among acute PE patients. The volumetric assessment of CTPA may help identify patients who are at increased risk in a quantitative and fast method, immediately following the diagnostic CTPA.