Short-term results of retrograde pulmonary embolectomy in massive and submassive pulmonary embolism: a single-center study of 30 patients

Intermediate-Risk and High-Risk Pulmonary Embolism: Recognition and Management: Cardiology Clinics: Cardiac Emergencies

Pulmonary embolism (PE) is the third most common cause of cardiovascular death. Every specialty of medical practitioner will encounter PE in their patients, and should be prepared to employ contemporary strategies for diagnosis and initial risk-stratification. Treatment of PE is based on risk-stratification, with anticoagulation for all patients, and advanced modalities including systemic thrombolysis, catheter-directed therapies, and mechanical circulatory supports utilized in a manner paralleling PE severity and clinical context.

Value of retrograde pulmonary vein perfusion combined with pulmonary artery thrombectomy in acute pulmonary embolism: a protocol for a systematic review and meta-analysis

INTRODUCTION

Acute pulmonary embolism is a serious cardiovascular disease with high mortality. Surgery is an important therapeutic means. The traditional surgical method is pulmonary artery embolectomy with cardiopulmonary bypass, but there is a certain recurrence rate after surgery. Some scholars use retrograde pulmonary vein perfusion as an adjunct to conventional pulmonary artery embolectomy. However, whether this method can be used safely for acute pulmonary embolism and its long-term effects remains unclear. Therefore, we plan to conduct a systematic review and meta-analysis to investigate whether retrograde pulmonary vein perfusion combined with pulmonary artery thrombectomy can be safely used in acute pulmonary embolism.

METHODS AND ANALYSIS

We will search key databases (Ovid MEDLINE, PubMed, Web of Science, Cochrane Library, China Science and Technology Journals and Wanfang) for studies on acute pulmonary embolism treated with retrograde pulmonary vein perfusion from January 2002 to December 2022. The useful information will be consolidated into a piloting spreadsheet. The Cochrane Risk of Bias Tool will be used to assess the bias. Data will be synthesised and heterogeneity will be evaluated. The dichotomous variables will be determined by using risk ratio with 95% CI, and weighted mean differences (with 95% CI) or standardised mean differences (95% CI) will be used for continuous variables. Χ² test and I² test will be used to assess the statistical heterogeneity. Meta-analysis will be conducted when strong homogeneous data are accessible.

ETHICS AND DISSEMINATION

Approval of the ethics committee is not needed for this review. While results will be disseminated electronically, effective dissemination will be done through presentations and peer-reviewed publication.

PROSPERO REGISTRATION NUMBER

CRD42022345812; pre-results.

Interventional Treatment of Pulmonary Embolism

Pulmonary embolism (PE) is a serious and prevalent cause of vascular disease. Nevertheless, optimal treatment for many phenotypes of PE remains uncertain. Treating PE requires appropriate risk stratification as a first step. For the highest-risk PE, presenting as shock or arrest, emergent systemic thrombolysis or embolectomy is reasonable, while for low-risk PE, anticoagulation alone is often chosen. Normotensive patients with PE but with indicia of right heart dysfunction (by biomarkers or imaging) constitute an intermediate-risk group for whom there is controversy on therapeutic strategy. Some intermediate-risk patients with PE may require urgent stabilization, and ≈10% will decompensate hemodynamically and suffer high mortality, though identifying these specific patients remains challenging. Systemic thrombolysis is a consideration, but its risks of major and intracranial hemorrhages rival overall harms from intermediate PE. Multiple hybrid pharmacomechanical approaches have been devised to capture the benefits of thrombolysis while reducing its risks, but there is limited aggregate clinical experience with such novel interventional strategies. One method to counteract uncertainty and generate a consensus multidisciplinary prognostic and therapeutic plan is through a Pulmonary Embolism Response Team, which combines expertise from interventional cardiology, interventional radiology, cardiac surgery, cardiac imaging, and critical care. Such a team can help determine which intervention-catheter-directed fibrinolysis, ultrasound-assisted thrombolysis, percutaneous mechanical thrombus fragmentation, or percutaneous or surgical embolectomy-is best suited to a particular patient. This article reviews these various modalities and the background for each.

Surgical Embolectomy for Acute Pulmonary Thromboembolism

Acute pulmonary thromboembolism is a catastrophic event, especially for hospitalized patients. The prognosis of pulmonary thromboembolism depends on the degree of pulmonary arterial occlusion. The mortality of massive pulmonary embolism is reportedly as high as 25% without cardiopulmonary arrest and 65% with cardiopulmonary arrest. In patients with unstable hemodynamics due to pulmonary thromboembolism, surgical pulmonary embolectomy is indicated for patients with a contraindication to thrombolysis, failed catheter therapy, or failed thrombolysis. Thrombolytic therapy adds an additional burden on patients who are at risk of potential hemorrhagic complications. It is also indicated if patients are already on a veno-arterial extra-corporate membrane oxygenator for circulatory collapse or cardiopulmonary arrest. The outcome for patients who require cardiopulmonary resuscitation for longer than 30 minutes is poor. Therefore, early triage for massive and sub-massive pulmonary embolism is crucial. A team approach including a cardiovascular surgeon may be effective to save critically ill patients. Prompt removal of emboli reduces the right ventricular load with quick recovery of cardiopulmonary function in the early postoperative period. A recent series reported excellent results, with in-hospital mortality of less than 10%. Surgical pulmonary embolectomy is an effective, safe, and easy procedure to save critical patients due to pulmonary thromboembolism.

Surgical embolectomy versus thrombolytic therapy in the management of acute massive pulmonary embolism: Short and long-term prognosis

OBJECTIVE

Comparison between surgical embolectomy and thrombolytic therapy in patients suffering from acute massive pulmonary embolism (AMPE).

BACKGROUND

Prompt treatment of AMPE is necessary, although optimal management is a matter of debate.

METHODS

Patients with AMPE were assigned to either thrombolytic therapy or pulmonary surgical embolectomy. Early and late mortality, systolic pulmonary artery pressure (SPAP), right ventricular diameter (RVD) and bleeding complications were evaluated.

RESULTS

Seventy eight patients were treated with thrombolytic therapy and 30 patients underwent surgery. The difference between pre-intervention and third-day post-intervention in terms of RVD and SPAP was significantly greater in patients under surgical embolectomy (P < 0.001). There was a significant decline in RVD and SPAP in both groups during follow-up (P < 0.001). Mortality rate in the surgical embolectomy group was lower than the thrombolytic group although not significantly.

CONCLUSION

Early surgical treatment was associated with fewer complications in comparison to thrombolytic therapy.

Surgical Embolectomy for Acute Massive and Submassive Pulmonary Embolism in a Series of 115 Patients

BACKGROUND

Pulmonary embolectomy is often indicated for central pulmonary embolism (PE) with hemodynamic instability, but remains controversial for hemodynamically stable patients with signs of right ventricular dysfunction. Because thrombolytic therapy is often contraindicated postoperatively, we reviewed risk factors and outcomes of pulmonary embolectomy for stable and unstable central PE, particularly in the early postoperative period.

METHODS

Between October 1999 and September 2013, 115 patients underwent pulmonary embolectomy for central, hemodynamically unstable PE (49 of 115, 43%) or hemodynamically stable PE (56 of 115, 49%). Ten operations for alternate indications (right atrial mass, endocarditis) were excluded for comparison analysis, leaving 105 patients.

RESULTS

Mean age was 59 ± 13 years; 46 of 105 patients (44%) had recent surgery (within 5 weeks): orthopedic (12 of 46, 25%), neurosurgery (11 of 46, 24%), or general surgery (10 of 46, 22%). Preoperative demographics did not differ between groups, except for the frequency of cardiopulmonary resuscitation among unstable patients (11 of 49, 22%) versus stable patients (0 of 56, 0%; p < 0.001). Operative mortality for the combined groups was 6.6% (7 of 105): unstable 10.2% (5 of 49) versus stable 3.6% (2 of 56; p = 0.247). Of 11 patients requiring preoperative cardiopulmonary resuscitation, 4 died. Six-month, 1-year, and 3-year survival rates were, respectively, 75%, 68.4%, and 65.8% for unstable PE, and 92.6%, 86.7%, and 80.4% for stable PE (p = 0.018).

CONCLUSIONS

This large series of pulmonary embolectomies demonstrates excellent early and late survival rates for patients with stable PE and unstable PE. These findings confirm pulmonary embolectomy as a beneficial therapeutic option for central PE, especially during the postoperative period when thrombolytic therapy is often contraindicated.

Retrograde pulmonary perfusion as an adjunct to standard pulmonary embolectomy for acute pulmonary embolism

Mortality rates for pulmonary embolectomy in patients with acute massive pulmonary embolism have decreased in recent years. However, it still ranges from 30 to 45% when surgery is performed on critically ill patients, and the mortality rates reach 60% in patients who have experienced a cardiac arrest before the procedure. The causes of death in these patients are generally attributed to right heart failure due to persistent pulmonary hypertension, intractable pulmonary oedema, and massive parenchymal and intrabronchial haemorrhage. Clinical and experimental findings indicate that venous air embolism causes severe or even lethal damage to the pulmonary microvasculature and the lung parenchyma consequent to the release of endothelium-derived cytokines. These findings are similar to those observed when severely compromised patients undergo pulmonary embolectomy for air entrapped in the pulmonary artery during embolectomy, which may lead to fatal outcomes. Retrograde pulmonary perfusion (RPP), besides enabling the removal of residual thrombotic material from the peripheral branches of the pulmonary artery, fills the pulmonary artery with blood and prevents pulmonary air embolism. We believe that the use of RPP as an adjunct to conventional pulmonary embolectomy decreases the morbidity and mortality rates associated with pulmonary embolectomy in critically ill patients.

Residual pulmonary hypertension after retrograde pulmonary embolectomy: long-term follow-up of 30 patients with massive and submassive pulmonary embolism

OBJECTIVES

Pulmonary hypertension is a major cause of morbidity and mortality in patients following acute pulmonary embolism. Although thrombolytic therapy decreases pulmonary arterial pressure, compared with anticoagulation alone, it has the propensity for haemorrhagic complications, distal embolization and incomplete recanalization, with the potential risk of late pulmonary hypertension. Surgical embolectomy-once performed solely on critically-ill patients-has now gained favour in a wider range of patients. In this paper we present the outcomes of patients who underwent surgical embolectomy complemented with retrograde technique and follow-up systolic pulmonary arterial pressure (SPAP).

METHODS

From January 2004 to December 2010, 30 consecutive patients with a mean age of 58±15 years underwent pulmonary embolectomy at our centre. The patients were followed for a mean period of 30.5±12 months. Their New York Heart Association (NYHA) classifications were assessed and their SPAPs were measured by echocardiography.

RESULTS

The overall mortality rate was 13.2% (4/30). Of the remaining patients, 19 patients (73.1%) were in NYHA classes I and II, 7 patients (26.9%) in class III and no patient in class IV. The patients' preoperative and postoperative mean SPAPs were 44.9±5.7 and 34.9±7.1 mmHg, respectively, which showed a significant reduction (P<0.001). The mean SPAP in the follow-up was 29.4±11.5 mmHg, which again showed significant reduction compared with early postoperation values (P<0.001). No significant correlations were found between the level of SPAP reduction in patients' follow-up with age (P=0.727) and total days of ICU admission (P=0.700), but weak correlations with sex (P=0.016) and total intubation time were noticed (P=0.035).

CONCLUSIONS

This is the first series reporting the long-term outcome of patients undergoing surgical embolectomy complemented by retrograde embolectomy technique, demonstrating the safety and favourable long-term outcome of this technique. It is also a new element in the growing body of evidence regarding the relevance of surgical embolectomy in patients with acute pulmonary embolism. We concluded that, following surgery, not only does the pulmonary arterial pressure drop immediately, but also the trend toward normalization continues long after operation.

Case fatality rate with pulmonary embolectomy for acute pulmonary embolism

BACKGROUND

There are insufficient data to assess the potential role of pulmonary embolectomy in patients with acute pulmonary embolism.

METHODS

In-hospital all-cause case fatality rate with pulmonary embolectomy was assessed from the Nationwide Inpatient Sample from 1999 through 2008.

RESULTS

Among unstable patients (in shock or ventilator-dependent), case fatality rate with embolectomy was 380 of 950 (40%). Among stable patients, case fatality rate was lower: 690 of 2820 (24%) (P <.0001). Case fatality rate in unstable patients was 39% in 1999-2003 and 40% in 2004-2008 (not significant), and in stable patients it was 27% in 1999-2003 and 23% in 2004-2008 (P=.01). Case fatality rates were lower in patients with a primary diagnosis of pulmonary embolism and even lower in patients with a primary diagnosis who had none of the comorbid conditions listed in the Charlson Index. Within each stratified group, patients with vena cava filters had a lower case fatality rate.

CONCLUSIONS

Case fatality rate in unstable patients who underwent pulmonary embolectomy remained at 39%-40% from 1999-2003 to 2004-2008, and in stable patients it decreased only from 27% to 23%. Case fatality rates were lower in those with fewer comorbid conditions and in those who received a vena cava filter. Our data reflect average outcome in the US. It may be that experienced surgeons and an aggressive multidisciplinary team could obtain a lower case fatality rate.

Massive pulmonary embolism: surgical embolectomy versus thrombolytic therapy--should surgical indications be revisited?

OBJECTIVES

The treatment of massive pulmonary embolism (PE) is a matter of debate. We present our institutional experience of patients suffering from massive PE with the aim of comparing the early results, the outcome and quality of life (QoL) between patients primarily assigned to either pulmonary surgical embolectomy (SE) or thrombolytic therapy (TL). A subgroup of patients (TS) with failed responses to TL requiring SE was separately analysed.

METHODS

All consecutive patients (January 2001-December 2007) with computed tomography (CT)-scan-confirmed massive bilateral central or paracentral PE were reviewed. All clinical data were retrieved from our patients' registry and completed by the evaluation of the CT-scan-derived right ventricle/left ventricle ratio (RV/LV ratio). Follow-up focused on clinical outcome and QoL was obtained.

RESULTS

Eighty patients were analysed including 28 SE (35%) and 52 TL (65%), of whom 11 (21%) required TS. Demographics and preoperative characteristics were similar between SE and TL. Analysis of the RV/LV ratio revealed a ratio of 1.66 for SE and 1.44 for TL. The early mortality rate was not significantly different between the two groups (SE: 3.6% versus TL: 13.5%), whereas early mortality was 27% in those patients treated initially with thrombolysis and subsequently requiring SE (TS-group). Severe bleeding complications were lower in the SE-group (3.6% versus 26.5% P = 0.013). Intracerebral bleeding rates and neurological events were not statistically different. After a mean follow-up of 63 ± 21 months, the mortality rate was 17.9% in the SE-group and 23.1% in the TL-group.

CONCLUSIONS

SE is an excellent treatment option in massive PE with comparable early mortality rates and significantly less bleeding complications than TL. Patients having surgery after inefficient thrombolysis have the worst early outcome. The RV/LV CT-scan ratio might serve as a predictor to differentiate patients, who could profit from direct surgical intervention than thrombolytic treatment attempts. Further studies are required to confirm these results.