Factors determining altered perfusion after acute pulmonary embolism assessed by quantified single-photon emission computed tomography-perfusion scan

Abstract

AIM OF THE STUDY:The aim of the study was to analyze the evolution of perfusion (Q)-defects in patients treated for acute pulmonary embolism (PE), correlation with baseline parameters and evaluation of recurrence risk.METHODS:This is a single-center prospective observational cohort study in symptomatic normotensive PE. Comparison of the ventilation/perfusion single-photon emission computed tomography (V/Q-SPECT) acquired at baseline with a quantified SPECT (Q-SPECT) repeated at 1 week and 6 months. The Q-defect extent (percentage of total lung volume affected) was measured semiquantitatively. Data collected at baseline were age, gender, body mass index (BMI), history of previous venous thromboembolism (HVTE), Charlson's Comorbidity Score (CcS), plasma troponin-T and D-dimer levels, PE Severity Index, and tricuspid regurgitation jet (TRJ) velocity.RESULTS:Forty-six patients (22 men/24 women, mean age 61.7 years (± standard deviation 16.3)) completed the study. At 1 week, 13/46 (28.3 %) and at 6 months 22/46 (47.8%) patients had completely normalized Q-SPECT. Persistence of Q-defects was more frequent in female patients in univariate and multivariate analysis. We found no correlation between the persistence of Q-defects on Q-SPECT and HVTE, BMI, plasma troponin-T, and CcS. However, lower TRJ and younger age were statistically significantly linked to normalization of Q-scans after 6 months of treatment only in univariate analysis. There is no difference in the frequency of recurrent PE in relation to the persistence of Q-defects.CONCLUSION:Acute PE patients of female, older age, and higher TRJ in univariate analysis and patients of female in multivariate analysis seem to have a higher risk of persistent Q-defects after 6 months treatment. The presence of residual Q-abnormalities at 6 months was not associated with an increased risk for recurrent PE.

Risk of recurrent venous thromboembolism after acute pulmonary embolism: Role of residual pulmonary obstruction and persistent right ventricular dysfunction. A meta‐analysis

“…Overall, 192 of 1294 patients with RPO had recurrent VTE (14.8%; 95% CI 13.0‐16.8), as compared with 176 of 2178 without RPO (8.1%; 95% CI 7.0‐9.3). The presence of RPO, either on CT angiography or on lung scan, was associated with an increased risk of recurrent VTE without significant heterogeneity (16 studies; 3472 patients; OR according to the random‐effects model, 2.22; 95% CI 1.61‐3.05; I 2 = 26%) (Figure ) . The association was confirmed after amending for zero cells (OR 2.13; 95% CI 1.56‐2.90) and after excluding from the analysis the study by Meneveau et al, in which RPO was assessed at an early stage (OR 2.11; 95% CI 1.52‐2.93).…”

“…The association between RPO and recurrent VTE was confirmed in studies assessing RPO on lung scan (11 studies; 2916 patients; OR 2.21; 95% CI 1.63‐3.01; I 2 = 16%), but not in studies assessing RPO on CT angiography, although there was significant heterogeneity (five studies; 556 patients; OR according to the random‐effects model, 2.56; 95% CI 0.82‐7.94; I 2 = 52%) …”

“…Overall, 538 papers were found, of which 16 met the inclusion criteria (the flow diagram is shown in Figure S1). In one study, the numbers of patients with or without RPO who had recurrent VTE events were obtained after the authors had been contacted . The agreement between reviewers for study selection was good (kappa statistic of 0.85).…”

Development of early reperfusion after the first episode of acute pulmonary embolism

“…V práci Meysmana a spol. [5] byly reziduální perfuzní defekty u 52,2 % nemocných vyšetřených perfuzním plicním skenem po šesti měsících adekvátní terapie.…”

“…[4], Meysman a spol. [5] zjistili, že pacienti s perzistujícími perfuzními defekty byli starší než ti s kompletní reperfuzí. V práci Meysmana a spol.…”