Evaluation of QT/QTc ratio, laboratory parameters, pi (perfusion index) and pvi (pletismographic variability index) values for prognosis and mortality prediction in patients diagnosis of pulmonary emboli in the emergency service

Pulmonary embolism (PE) is the third most common cause of cardiovascular death. Ventilation/perfusion dysfunction occurs when the pulmonary artery and/or its branches are mechanically and functionally occluded, usually by a thrombus. The perfusion index (PI) indicates peripheral perfusion and the plethysmographic variability index (PVI) indicates the dynamic change in PI during a given respiratory cycle. Scoring and classification methods have been developed for diagnosis, treatment and mortality prediction. These include PESI and early mortality risk stratification. Glaskow coma scale (GCS), respiratory rate, laboratory, electrocardiography, computed tomography pulmonary angiography (CTPA) findings are also used. Long QT and QTc intervals, high lactate levels, low PaO2 and high right ventricular/left ventricular diameter ratio are indicators of poor prognosis. Our study is a prospective and single center study. The aim of our study was to evaluate the effect of QT/QTc ratio, laboratory parameters, PI and PVI values on mortality in PE patients. A total of 49 patients, 23 (46.9%) women and 26 (53.1%) men, who were diagnosed with PE by BTPA, were included in our study. While 24.4% of the patients died, 75.6% survived. Lactate and PI were successful in predicting PESI scoring, early mortality risk stratification and hospitalization status; PaO2 was successful in predicting early mortality risk stratification and hospitalization status; RV/LV ratio was successful in predicting PESI scoring. The highest AUC was lactate (0.827), the highest specificity (83.78%) and PPV (53.8%) was PVI, and the highest sensitivity (100%) and NPV (100%) was PESI. Each point below the PI cut-off (≤1.9) was associated with a 469% increase in mortality, each point above the PVI cut-off (>40) was associated with a 404% increase in mortality, and each point above the PESI cut-off (>60) was associated with a 2% increase in mortality (p: 0.023, 0.009, 0.019, respectively). PVI and PI were found to be effective in the one-year survey analysis (p: 0.001, 0.001, respectively). PI and PVI were correlated with GCS, respiratory rate and each other. PI is also correlated with PESI. In our study, PI and PVI measured at admission were found to be successful in predicting 1-year mortality in patients diagnosed with PE in the emergency department. Keywords: Pulmonary embolism, QT/QTc ratio, perfusion index, plethysmographic variability index, mortality