Pulmonary thromboembolism with computed tomography defined chronic thrombus is associated with higher mortality

Sequelae of Acute Pulmonary Embolism: From Post-Pulmonary Embolism Functional Impairment to Chronic Thromboembolic Disease

Among survivors of acute pulmonary embolism (PE), roughly half report persistent dyspnea, impaired functional status, and decreased quality of life. Post-pulmonary embolism syndrome (PPES) is a broad condition which has been increasingly recognized in recent years and may be due to post-pulmonary embolism functional impairment, chronic thromboembolic disease, or the most severe long-term complication of PE, chronic thromboembolic pulmonary hypertension. Despite guideline recommendations for appropriate follow-up for post-pulmonary embolism patients, PPES remains underrecognized and diagnostic testing underutilized. Patients with symptoms suggestive of PPES at follow-up should undergo a transthoracic echocardiogram to screen for the presence of pulmonary hypertension; additional testing, such as a ventilation/perfusion scan, right heart catheterization, and cardiopulmonary exercise testing may be indicated. The pathophysiology of post-pulmonary embolism syndrome is complex and heterogeneous. In chronic thromboembolic pulmonary hypertension, the pathophysiology reflects persistent pulmonary arterial thrombi and a progressive small vessel vasculopathy. In patients with chronic thromboembolic disease or chronic thromboembolic pulmonary hypertension, medical therapy, balloon pulmonary angioplasty, or pulmonary thromboendarterectomy should be considered, and in cases of chronic thromboembolic pulmonary hypertension, pulmonary thromboendarterectomy significantly improves mortality. In all causes of post-pulmonary embolism syndrome, rehabilitation is a safe treatment option that may improve quality of life.

Chronic thromboembolic disease among patients undergoing surgical pulmonary embolectomy for acute pulmonary embolism

BACKGROUND

This study aimed to assess the prevalence of chronic thromboembolic lesions in the pulmonary arteries among patients undergoing pulmonary embolectomy for acute pulmonary embolism and their impact on treatment outcomes.

METHODS

We conducted a retrospective, single-center analysis of consecutive patients undergoing emergency pulmonary embolectomy for acute pulmonary embolism between 2013 and August 2021. According to European Society of Cardiology guidelines, the diagnosis was based on clinical presentation, imaging studies and laboratory tests. Surgery was selected as the optimal treatment modality within the Pulmonary Embolism Response Team. Based on the intraoperatively identified chronic lesions patients were divided into two groups: acute only and acute/chronic. The analysis comprised history, laboratory and imaging studies, early and long-term mortality, and postoperative complications. We determined predictive factors for chronic thromboembolic lesions and risk factors for death.

RESULTS

The analysis included 33 patients. Intraoperatively, 42% (14) of patients had chronic lesions. Predictive factors for these lesions are the duration of symptoms >1 week (OR=13.75), pulmonary artery dilatation >3.15 cm (OR=39.00) and right ventricle systolic pressure >52 mmHg (OR=29.33). No hospital deaths occurred in the acute only group and two in the acute/chronic group (0% vs. 14.3%; P=0.172). Risk factors for death are the duration of symptoms >3 weeks (HR=7.35) and postoperative use of extracorporeal membrane oxygenation (HR=7.04).

CONCLUSIONS

Acute thromboembolic disease overlapping chronic clots is relatively common among patients undergoing pulmonary artery embolectomy. A detailed evaluation of the patient's medical history and imaging studies can identify these patients, as they require special attention when making treatment decisions. Surgical treatment in a center of expertise in pulmonary endarterectomy seems reasonable.

Evolutionary changes in thrombus features on computed tomography: An effective approach for identifying subacute pulmonary embolism

OBJECTIVE

Thrombus features on computed tomography (CT) play a key role in distinguishing between acute and chronic pulmonary embolisms (PEs). However, the thrombus features of subacute PE are largely unknown.

METHODS

This retrospective study included 358 patients (age, 65 ± 16 years; percentage of men, 38%) diagnosed with PE from 2008 to 2019. The patients were divided into a study group and a verification group. Thrombus features that changed over time were determined in the study group according to the time of PE occurrence. Next, we determined the thrombus features of subacute PE and verified them in the verification group. Finally, we compared clinical deterioration and the 1-month mortality rate between the patients with acute and subacute PEs.

RESULTS

The main feature of eccentric thrombi that changed over time was the angle with the arterial wall, whereas those of centric thrombi were recanalization and heterogeneity. Taken together, the features of subacute PE were determined to be an obtuse angle with the arterial wall, recanalization, and heterogeneity. The accuracy of these features in identifying subacute PE was 94% during verification. Between the patients with acute and subacute PEs, there was no significant difference in clinical deterioration (19% vs 14%; P = .32) or the 1-month mortality rate (15% vs 8%; P = .11). With multivariate analysis, subacute events were also not associated with clinical deterioration (P = .8) or the 1-month mortality rate (P = .11).

CONCLUSIONS

We determined the time trend of thrombus features on CT in patients with PE and found that these features can improve the identification of subacute events. Patients with acute and subacute PEs do not have different risks of clinical deterioration and 1-month mortality.

Features and incidence of thromboembolic disease: A comparative study between high and low altitude dwellers in Saudi Arabia

To estimate and compare the incidence of thromboembolic disease among patients who are clinically suspected for VTE among high and low altitude dwellers in Saudi Arabia. A prospective study conducted over two years (2011–2013) conducted in two different geographical areas in Saudi Arabia; Abha City and Riyadh City. Patients clinically suspected with deep vein thrombosis and pulmonary embolism was recruited to the study. A detailed social, medical and laboratory investigations were taken from all patients including lifestyle, occupation and smoking. A total of 234 patients participated in the study. There were 146 (62.4%) females and 88 (37.6%) males. Mean age was 51.7 years. A 56.8% incidence of DVT was seen among high altitude dwellers compared to 13.0% among low altitude dwellers. Also, a 12.6% incidence of PE was documented among high altitude dwellers, compared to 4.1% of the low altitude dwellers. VTE was significantly more among high altitude dwellers (81.9%) compared to low altitude dwellers (21.9%). Mean WBC count was significantly higher among the high altitude dwellers (10.8 ± 9.7 vs. 8.2 ± 3.4, p = 0.043). Mean platelet count was significantly higher among the high altitude dwellers compared to the low altitude dwellers (327.4 ± 162.4 vs. 212.0 ± 158.9, p = 0.005). The likelihood of developing VTE is greater among people who resided at moderate to high altitude for prolonged periods of time. The changes in the factors for coagulation including platelet counts may not reflect the true status of hypercoagulability especially if patients have stayed longer in high altitudes because of physiological adaptation to the environment.