Residual Pulmonary Obstruction Research Articles

Identification of outcomes in clinical studies of interventions for venous thromboembolism in non‐pregnant adults

Identification of outcomes in clinical studies of interventions for venous thromboembolism in non‐pregnant adults

Prognostic factors of clot resolution on follow‐up computed tomography angiography and recurrence after a first acute pulmonary embolism

Recent studies seem to confirm the relationship between residual pulmonary obstruction (RPO) in pulmonary embolism (PE) and risk of recurrent thrombosis and chronic thromboembolic pulmonary hypertension (CTEPH). However, the prognostic factors associated with PE resolution on follow-up computed tomography angiography (CTA) are not clear. To determine the prognostic factors of resolution of PE diagnosed and monitored by CTA and the impact of RPO on late complications. We retrospectively analyzed 241 patients with PE who had undergone a 12-month follow-up and CT scan evaluation at 6months. Factors related to resolution and the impact of RPO on the outcome were analyzed. Resolution was achieved in 74.3% of all cases after 6months of treatment. Absence of chronic obstructive pulmonary disease (COPD) (OR, 3.22 [1.35-7.71]; p=0.009), provoked PE (OR, 2.02 [1.08-3.79]; p=0.028), early initiation of treatment (<7days) (OR, 2.42 [1.22-4.78]; p=0.011), and degree of obstruction caused by the initial PE as indicated by a Qanadli score lower than 16 (OR, 2.12 [1.03-4.37]; p=0.043) were associated with complete resolution. RPO was associated with recurrent PE as well as the combined endpoint consisting of recurrent VTE and/or CTEPH (4.67 [95% CI, 1.26-17.26]; p=0.02) and (OR 6.4 [95% CI, 1.9-21.2]; p<0.005), respectively. Resolution of PE is associated with a lower risk of recurrent thrombosis. Earlier initiation of treatment improves prognosis as measured by resolution on follow-up CTA.

A significant decrease in D-dimer concentration within one month of anticoagulation therapy as a predictor of both complete recanalization and risk of recurrence after initial pulmonary embolism

BackgroundAbnormal D-dimer concentration measured during anticoagulation therapy (AT) or within one month of discontinuation, is associated with residual pulmonary obstruction (RPO) and risk of recurrent venous thromboembolism (VTE) after a first episode of pulmonary embolism (PE). We hypothesized that a significant decrease in D-dimer concentration within the first month of AT in patients with a first episode of PE may predict complete recanalization and a lower risk of recurrent VTE. MethodsOne hundred and fifty patients with PE received anticoagulation therapy for three or six months when control computed tomography angiography (CTA) was performed. D-dimer levels were measured at admission and at 1-, 3- and/or 6-month follow-ups after the initial event. Clinical, echocardiographic, CTA and analytical data were collected. Predictive factors of RPO and predictive ability of D-dimer concentration at 1- and 6-month follow-ups were evaluated. ResultsOf the 150 eligible patients, 33 (22%) had RPO in control CTA. Idiopathic PE, a delay of >7 days between symptom onset and diagnosis, and clinical PE severity determined by a s-PESI score ≥ 1 were associated with RPO. D-dimer concentration within a month of AT was significantly higher (823 [558–1259] vs 436 [243–934] ng/ml; p = 0.019) in patients with RPO; decrease (445 [35–1899] vs 912 [476–2858] ng/ml; p = 0.047) and decrease percentage (31.4% vs 76.6%; p < 0.005) in D-dimer concentrations were significantly lower. ROC analysis showed that decrease percentage in D-dimer concentration identified patients with complete recanalization (AUC 0.715, [95% CI, 0.611–0.819], p < 0.005). Decreases of >70% in initial D-dimer at 1-month (OR, 0.56, [95% CI, 0.45–0.70] p = 0.037) and 6-month follow-ups (OR, 0.31 [CI 95%, 0.15–0.66], p = 0.03) were associated with a lower risk of recurrent PE. ConclusionA significant decrease in D-dimer concentration within the first month of AT is associated with complete recanalization and could predict a lower risk of recurrent thrombosis after a first episode of PE.

Impact of residual pulmonary obstruction on the long-term outcome of patients with pulmonary embolism

The impact of residual pulmonary obstruction on the outcome of patients with pulmonary embolism is uncertain.We recruited 647 consecutive symptomatic patients with a first episode of pulmonary embolism, with or without concomitant deep venous thrombosis. They received conventional anticoagulation, were assessed for residual pulmonary obstruction through perfusion lung scanning after 6 months and then were followed up for up to 3 years. Recurrent venous thromboembolism and chronic thromboembolic pulmonary hypertension were assessed according to widely accepted criteria.Residual pulmonary obstruction was detected in 324 patients (50.1%, 95% CI 46.2-54.0%). Patients with residual pulmonary obstruction were more likely to be older and to have an unprovoked episode. After a 3-year follow-up, recurrent venous thromboembolism and/or chronic thromboembolic pulmonary hypertension developed in 34 out of the 324 patients (10.5%) with residual pulmonary obstruction and in 15 out of the 323 patients (4.6%) without residual pulmonary obstruction, leading to an adjusted hazard ratio of 2.26 (95% CI 1.23-4.16).Residual pulmonary obstruction, as detected with perfusion lung scanning at 6 months after a first episode of pulmonary embolism, is an independent predictor of recurrent venous thromboembolism and/or chronic thromboembolic pulmonary hypertension.

Functional status of patients with large ventricular septal defect and pulmonary vascular disease 6 to 16 years after surgical closure of their defect in childhood.

We have reviewed 27 patients now 6 to 16 years after closure of a ventricular septal defect at 3 to 12 years of age associated with pulmonary hypertension with a view to assessing their quality of life, respiratory function, and exercise performance. All the patients led normal unrestricted lives. Their subjective lack of symptoms was, in general, confirmed by the results obtained from assessment of lung function tests and two-stage exercise testing in 19 volunteers. Abnormal ventilation in relation to work load was noted in 5 patients and a slightly low exercise cardiac output in 6. Although the patients led normal lives and had a satisfactory response to exercise, measurement of pulmonary artery pressure showed striking pulmonary hypertension on effort. Despite the satisfactory progress of these patients their more long-term future must be one of conjecture and their residual pulmonary hypertension, indicative of residual pulmonary obstruction, must lend weight to arguments for earlier closure of ventricular septal defect before 1 to 2 years of age when changes in the pulmonary vascular bed may be reversed after closure of the defect.