Surgical Treatment of Acute Massive Pulmonary Embolism

Intraoperative circulatory arrest secondary to high-risk pulmonary embolism. Case series and updated literature review

BACKGROUND

Intraoperative pulmonary embolism (PE) with cardiac arrest (CA) represents a critical and potentially fatal condition. Available treatments include systemic thrombolysis, catheter-based thrombus fragmentation or aspiration, and surgical embolectomy. However, limited studies are focused on the optimal treatment choice for this critical condition. We present a case series and an updated review of the management of intraoperative CA secondary to PE.

METHODS

A retrospective review of patients who developed high-risk intraoperative PE was performed between June 2012 and June 2022. For the updated review, a literature search on PubMed and Scopus was conducted which resulted in the inclusion of a total of 46 articles.

RESULTS

A total of 196 174 major non-cardiac surgeries were performed between 2012 and 2022. Eight cases of intraoperative CA secondary to high-risk PE were identified. We found a mortality rate of 75%. Anticoagulation therapy was administered to one patient (12.5%), while two patients (25%) underwent thrombolysis, and one case (12.5%) underwent mechanical thrombectomy combined with thrombus aspiration. Based on the literature review and our 10-year experience, we propose an algorithm for the management of intraoperative CA caused by PE.

CONCLUSION

The essential components for adequate management of intraoperative PE with CA include hemodynamic support, cardiopulmonary resuscitation, and the implementation of a primary perfusion intervention. The prompt identification of the criteria for each specific treatment modality, guided by the individual patient's characteristics, is necessary for an optimal approach.

The Function of microRNAs in Pulmonary Embolism: Review and Research Outlook

Pulmonary embolism (PE) is a common pathologic condition that frequently occurs in patients with deep venous thrombosis. Severe PE may critically suppress cardiopulmonary function, thereby threatening the life of patients. Chronic pulmonary hypertension caused by PE may lead to deterioration of respiratory dysfunction, resulting in complete disability. MicroRNAs (miRNAs) are a group of abundantly expressed non-coding RNAs that exert multiple functions in regulating the transcriptome via post-transcriptional targeting of mRNAs. Specifically, miRNAs bind to target mRNAs in a matching mechanism between the miRNA seed sequence and mRNA 3ʹ UTR, thus modulating the transcript stability or subsequent translation activity by RNA-induced silencing complex. Current studies have reported the function of miRNAs as biomarkers of PE, revealing their mechanism, function, and targetome in venous thrombophilia. This review summarizes the literature on miRNA functions and downstream mechanisms in PE. We conclude that various related miRNAs play important roles in PE and have great potential as treatment targets. For clinical application, we propose that miRNA biomarkers combined with traditional biomarkers or miRNA signatures generated from microchips may serve as a great predictive tool for PE occurrence and prognosis. Further, therapies targeting miRNAs or their upstream/downstream molecules need to be developed more quickly to keep up with the progress of routine treatments, such as anticoagulation, thrombolysis, or surgery.

New guidelines for the diagnosis and management of pulmonary embolism: Key changes

Pulmonary embolism (PE) is an important public health problem. In August 2019, the European Society of Cardiology in collaboration with the European Respiratory Society released new guidelines for the diagnosis and management of PE. We discuss the basic changes between these recent guidelines and the previous guidelines that were published in 2014. Regarding diagnosis, the new guidelines propose the use of an age-adjusted cut-off level of D-dimers instead of a fixed cut-off value. A D-dimer test adapted to clinical possibility should also be considered instead of fixed cut-off level of D-dimer. Detailed recommendations for the diagnosis of PE during pregnancy are also provided. Regarding risk stratification, assessment of PE-related early mortality risk is recommended. Moreover, the importance of right ventricular dysfunction is emphasized in low-risk patients. For further risk stratification of the severity of PE in patients without hemodynamic instability, use of validated scores that combine clinical, imaging and laboratory PE-related prognostic factors might also be considered. Regarding treatment, the possibility of early discharge is mentioned in patients without severe comorbidities, who are not of high risk for sudden death and in whom proper medical management at home and proper medical follow up can be ensured. The new guidelines also suggest that pro-brain natriuretic peptide levels, right ventricular function and the presence of thrombus in the right heart could be useful for guiding the decision of early discharge. Overall, these new guidelines introduce several key changes and knowledge and adherence to them will improve the outcome of patients with PE.

Long-Term Outcome of Thrombolytic Therapy for Massive Pulmonary Embolism in Pregnancy

A 25-year-old pregnant woman presented at 12 weeks of gestation with syncope and shortness of breath caused by massive pulmonary embolism. Due to persistent shock, fibrinolytic therapy with rtPA was administered. After fibrinolysis, clinical and hemodynamic response was excellent. No bleeding and fetal complications were recorded.