ST-Segment Alterations in the Electrocardiogram of Acute Pulmonary Thromboembolism: A Rabbit Model.

In this study, we investigated the mechanism underlying electrocardiogram (ECG) alterations in a rabbit model of acute pulmonary thromboembolism (PTE). Twelve healthy adult New Zealand white rabbits were used, with eight in the experimental group (PTE group) and four in the control group. After developing the rabbit model of acute PTE, ECG and coronary angiography were performed. HE staining was conducted on the right and left ventricular tissues, and polymerase chain reaction (PCR) was used to determine brain natriuretic peptide (BNP), tumor necrosis factor-alpha (TNF-?), and Troponin I (TNI) mRNA expression in the myocardium. There were considerable changes in the ST segment of the ECG in the PTE group. Coronary angiography revealed the absence of spasm, stenosis, and occlusion. In the plasma of the PTE group, the levels of D-dimer, BNP, TNF-?, and TNI were significantly elevated, and these changes were statistically significant (P<0.05). PCR analysis of ventricular myocardial tissue indicated significantly higher levels of BNP, TNF-?, and TNI mRNA in the PTE group than in the control group. These differences were statistically significant (P<0.05). The ST-T variations on the ECG of rabbits with acute PTE correlate strongly with the temporary changes in right heart volume caused by acute PTE. Keywords: Animal model of pulmonary embolism, B-type natriuretic peptide, Electrocardiogram, Pulmonary thromboembolism, Troponin I, Tumor necrosis factor-alpha.

ECG changes following balloon pulmonary angioplasty in patients with chronic thromboembolic pulmonary hypertension: a retrospective study.

PURPOSE: This research evaluates the effect of balloon pulmonary angioplasty (BPA) on cardiac electrophysiological changes in patients with chronic thromboembolic pulmonary hypertension (CTEPH). METHODS: Involving a retrospective analysis of 39 CTEPH patients (average age 61 ± 11), who had at least two BPAs and paired ECGs pre- and post-surgery, we examined changes in ECG indicators of right ventricular hypertrophy and their correlation with hemodynamic results. RESULTS: BPA yielded marked improvements in cardiac function and hemodynamics. ECG parameters, specifically the Lewis criteria and Butler-Leggett score, correlated strongly with hemodynamics and were predictive of a mean pulmonary arterial pressure (mPAP) ≥ 35mmHg. Notably, QRS complex axis normalization was observed in 25 patients, with 14 fully normalizing (range - 30° to + 90°). The qR pattern in V1 vanished in 9 cases, and 75% of the patients in qR pattern in V1 group had QRS complex electrical axis completely returned to normal range. The qR V1 group had higher mPAP and pulmonary vascular resistance (PVR), and lower cardiac output and index compared to the non-qR V1 group, alongside a higher Butler-Leggett score. CONCLUSIONS: BPA enhances cardiac function and hemodynamics in CTEPH patients, with certain ECG measures such as Lewis criteria and Butler-Leggett score reflecting the severity of hemodynamic impairment. The reversal of QRS axis deviation and the disappearance of the qR pattern in lead V1 may serve as valuable indicators for assessing post-BPA satisfaction in CTEPH patients.

Effects of Ranolazine and Ivabradine on Pulmonary Microhemodynamics in Experimental Model of Pulmonary Thromboembolism.

We studied changes of pulmonary microhemodynamics when modeling pulmonary artery thromboembolism on perfused isolated rabbit lungs after pretreatment with ranolazine and ivabradine. The increase in pulmonary artery pressure, pulmonary vascular resistance, and pre- and postcapillary resistance was less pronounced than in control animals, but was close to that in case of pulmonary thromboembolism after pretreatment with voltage-gated Na+ channel blockers lidocaine and ropivacaine. The increase of capillary filtration coefficient inversely correlated with values of capillary hydrostatic pressure. Thus, ranolazine and ivabradine exhibit the properties of voltage-gated Na+ channel blockers mainly in smooth muscles of pulmonary arterial vessels and promote the decrease in endothelial permeability.

Extracorporeal Mechanical Circulatory Support after Pulmonary Thromboendarterectomy: Experience of One Center.

PURPOSE: Pulmonary thromboendarterectomy (PTE) is the treatment for patients with chronic thromboembolic disease. In the immediate postoperative period, some patients may still experience life-threatening complications such as reperfusion lung injury, airway bleeding, and persistent pulmonary hypertension with consequent right ventricular dysfunction. These issues may require support with extracorporeal membrane oxygenation (ECMO) as a bridge to recovery or lung transplantation. This study aims to analyze our series of PTEs that require ECMO. METHODS: A descriptive and retrospective analysis of all PTE performed at the Favaloro Foundation University Hospital was conducted between March 2013 and December 2023. RESULTS: A total of 42 patients underwent PTE with a median age of 47 years (interquartile range: 26-76). The incidence of patients with ECMO was 26.6%, of which 53.6% were veno-venous (VV) ECMO. Preoperatively, a low cardiac index (CI), high right and left filling pressures, and high total pulmonary vascular resistances (PVRs) were associated with ECMO with a statistically significant relationship. The hospital mortality was 11.9%, and the mortality in the ECMO group was 45.5%, with a statistically significant relationship. Veno-arterial ECMO has a worse prognosis than VV ECMO. CONCLUSIONS: Preoperatively, a low CI, high right and left filling pressures, and high total PVRs were associated with ECMO after PTE.

Cardiac Arrhythmias in Pulmonary Arterial Hypertension and Chronic Thromboembolic Pulmonary Hypertension: Mechanistic Insights, Pathophysiology, and Outcomes.

Arrhythmias are increasingly recognized as severe complications of precapillary pulmonary hypertension, encompassing pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH). Despite their significant contribution to symptoms, morbidity, in-hospital mortality, and potentially sudden death in PAH/CTEPH, there remains a lack of comprehensive data on epidemiology, pathophysiology, and outcomes to inform the management of these patients. This review provides an overview of the latest evidence on this subject, spanning from the molecular mechanisms underlying arrhythmias in the hypertrophied or failing right heart to the clinical aspects of epidemiology, diagnosis, and treatment.

Low nailfold capillary density in patients with pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension: biomarker of clinical outcome?

Nailfold capillary density is lower in patients with pulmonary arterial hypertension (PAH). It is unclear whether this observation signifies a unique systemic manifestation of PAH, or reflects microcirculatory dysfunction secondary to pulmonary hypertension (PH). Capillary density and loop dimensions were measured by nailfold-capillaroscopy (NC) in 30 PAH (23 idiopathic, or iPAH, 7 hereditary, or hPAH), 17 chronic thromboembolic PH (CTEPH) patients and 48 controls. NC-Measurements were repeated after pulmonary endarterectomy (PEA) or balloon pulmonary angioplasty (BPA) in CTEPH patients. We examined whether NC-measurements were related to markers of disease severity and predictive of time to clinical worsening (TTCW) as tested by univariate linear/logistic regression and cox-regression analysis, respectively. Capillary density was significantly lower in PAH (7.5 ± 1.1, p < 0.001) and in CTEPH (8.4 ± 1.5, p < 0.001) compared to asymptomatic controls (10.3 ± 1.0 capillaries/mm). Capillary density was similar in iPAH and hPAH and unrelated to hemodynamics in either PAH or CTEPH. A lower capillary density was predictive of clinical worsening in PAH (p 0.05). After normalization of pulmonary artery pressures by PEA or BPA, capillary density remained reduced in CTEPH patients. Capillary loop apex, capillary and venous- and arterial limb diameter were increased in patients with PAH and CTEPH compared to controls. Nailfold capillary density is reduced to a similar extent in iPAH, hPAH and CTEPH. Normalization of hemodynamics by PEA or BPA does not lead to a restoration of capillary density in CTEPH. Capillary dimensions were increased in both patients with PAH and CTEPH. Lower capillary density was predictive of clinical worsening in PAH. Our findings indicate that a loss of peripheral capillaries is not specific to PAH and is not related to the hemodynamic disturbance per se, but that shared mechanisms may account for a simultaneous development of a systemic microangiopathy and pulmonary vascular remodeling.

Post-pulmonary embolism syndrome: A reminder for clinicians.

Acute pulmonary embolism (APE) is one of the leading causes of cardiovascular emergencies and the third leading cause of death. Although efforts focus on treating the acute event, patients who survive APE may develop long-term sequelae. Research reveals that approximately half of patients who have suffered an APE do not regain their previous level of function and experience a reduction in their quality of life for several years after the episode. Acute pulmonary embolism can be classified according to the risk of short-term mortality, with most mortality and morbidity concentrated in high-risk and intermediate-risk cases. The first-line treatment for APE is systemic anticoagulation. However, identifying and more aggressively treating people with intermediate to high risk, who have a more favorable risk profile for reperfusion treatments, could reduce short-term mortality and mitigate post-pulmonary embolism syndrome (PPES). Post-pulmonary embolism syndrome refers to a variety of persistent symptoms and functional limitations that occur after an APE. The presence of persistent dyspnea, functional limitations, and/or decreased quality of life after an APE has been recently termed "PPES," although this entity encompasses different manifestations. The most severe cause of persistent dyspnea is chronic thromboembolic pulmonary hypertension, where increased pulmonary artery pressure is due to the fibrotic organization of unresolved APE. Post-PE Syndrome is not always systematically addressed in management guidelines, and its prevalence may be underestimated. More research is needed to fully understand its causes and risk factors. Interventions such as cardiopulmonary rehabilitation have been suggested to improve the quality of life of patients with PPES. A comprehensive, evidence-based approach is essential to effectively prevent and manage PPES and improve the long-term outcomes and well-being of affected patients.

Differential effects of balloon pulmonary angioplasty on chronic thromboembolic pulmonary disease.

BACKGROUND: Decreased diffusing capacity of the lungs for carbon monoxide (DLco) is associated with microvascular damage in chronic thromboembolic pulmonary hypertension (CTEPH). Balloon pulmonary angioplasty (BPA) is an effective treatment for CTEPH, but the efficacy of BPA in patients with CTEPH with low DLco remains unclear because BPA does not directly address microvascular damage. This study investigates the influence of microvasculopathy on BPA in CTEPH according to DLco. METHODS: We retrospectively analysed data from patients with inoperable CTEPH who underwent BPA at the University of Tokyo Hospital from July 2011 to August 2023. The patients were classified into two groups based on their preprocedural DLco (normal DLco (ND) and low DLco (LD) groups), with a DLco cut-off value of 80%. We compared the patient characteristics and effectiveness of BPA between the groups. RESULTS: Among the 75 patients, 36 were in the LD group. The LD group had a shorter 6-minute walking distance (324±91 vs 427±114 m) than the ND group but the mean pulmonary artery pressure (mPAP) was similar (38.9±7.3 vs 41.1±9.2 mm Hg) before BPA. BPA improved the haemodynamic status and exercise tolerance in both groups. The LD group exhibited a higher mPAP (25.1±7.4 vs 21.5±5.6 mm Hg) and required more sessions of BPA (median 6 vs 4). Based on the analysis of covariance adjusted for baseline values, low DLco significantly correlated with mPAP (sß=-0.304, 95% CI -7.015 to -1.132, p=0.007) and pulmonary vascular resistance (sß=-0.324, 95% CI -141.0 to -29.81, p=0.003). CONCLUSIONS: BPA was associated with an improvement in the haemodynamic status and exercise tolerance in patients with CTEPH even with low DLco. However, low DLco may attenuate the effect of BPA on mPAP and pulmonary vascular resistance and require more treatment sessions.

Percutaneous pulmonary aspiration thrombectomy in an adolescent fontan patient using a large-bore system.

We describe the safe and effective percutaneous pulmonary thrombectomy in an 18-year-old female with a Fontan circulation using the FlowTriever® device (Inari Medical®, Irvine, US). Aspiration thrombectomy of both pulmonary arteries was performed using 24 and 16 F FlowTriever® catheters retrieving large amounts of thrombus material resulting in near total angiographic recanalization.

Composite Pulmonary Embolism Shock Score and Risk of Adverse Outcomes in Patients With Pulmonary Embolism.

BACKGROUND: In hemodynamically stable patients with acute pulmonary embolism (PE), the Composite Pulmonary Embolism Shock (CPES) score predicts normotensive shock. However, it is unknown if CPES predicts adverse clinical outcomes. The objective of this study was to determine whether the CPES score predicts in-hospital mortality, resuscitated cardiac arrest, or hemodynamic deterioration. METHODS: Patients with acute intermediate-risk PE admitted from October 2016 to July 2019 were included. CPES was calculated for each patient. The primary outcome was a composite of in-hospital mortality, resuscitated cardiac arrest, or hemodynamic decompensation. Secondary outcomes included individual components of the primary outcome. The association of CPES with primary and secondary outcomes was evaluated. RESULTS: Among the 207 patients with intermediate-risk PE (64.7% with intermediate-high risk PE), 29 (14%) patients had a primary outcome event. In a multivariable model, a higher CPES score was associated with a worse primary composite outcome (adjusted hazard ratio [aHR], 1.81 [95% CI, 1.29-2.54]; P=0.001). Moreover, a higher CPES score predicted death (aHR, 1.76 [95% CI, 1.04-2.96]; P=0.033), resuscitated cardiac arrest (aHR, 1.99 [95% CI, 1.17-3.38]; P=0.011), and hemodynamic decompensation (aHR, 1.96 [95% CI, 1.34-2.89]; P=0.001). A high CPES score (≥3) was associated with the worse primary outcome when compared with patients with a low CPES score (22% versus 2.4%; P=0.003; aHR, 6.48 [95% CI, 1.49-28.04]; P=0.012). CPES score provided incremental prognostic value for the prediction of primary outcome over baseline demographics and European Society of Cardiology intermediate-risk subcategories (global Χ2 value increased from 0.63 to 1.39 to 13.69; P=0.005). CONCLUSIONS: In patients with acute intermediate-risk PE, the CPES score effectively risk stratifies and prognosticates patients for the prediction of clinical events and provides incremental value over baseline demographics and European Society of Cardiology intermediate-risk subcategories.

Plasma Deoxycholic Acid Levels are Associated with Hemodynamic and Clinical Outcomes in Acute Pulmonary Embolism Patients.

This study aimed to evaluate the correlation of plasma deoxycholic acid (DCA) levels with clinical and hemodynamic parameters in acute pulmonary embolism (APE) patients. Total 149 APE adult patients were prospectively recruited. Plasma DCA levels were measured using rapid resolution liquid chromatography-quadrupole time-of-flight mass spectrometry. Baseline clinical and hemodynamic parameters were evaluated according to plasma DCA levels. The plasma DCA levels were significantly lower in APE patients than in those without APE (P < 0.001). APE patients with adverse events had lower plasma DCA levels (P < 0.001). Low DCA group patients presented more adverse cardiac function, higher NT-proBNP levels (P = 0.010), and higher WHO functional class levels (P = 0.023). Low DCA group also presented with an adverse hemodynamic status, with higher pulmonary vascular resistance levels (P = 0.027) and lower cardiac index levels (P = 0.024). Both cardiac function and hemodynamic parameters correlated well with plasma DCA levels. Kaplan-Meier survival analysis demonstrated that APE patients with lower plasma DCA levels had a significantly higher event rate (P = 0.009). In the univariate and multivariate Cox regression analyses, the plasma DCA level was an independent predictor of clinical worsening events after adjusting for age, sex, WHO functional class, NT-proBNP level, pulmonary vascular resistance, and cardiac index (HR 0.370, 95% CI 0.161, 0.852; P = 0.019). Low plasma DCA levels predicted adverse cardiac function and hemodynamic collapse. A low DCA level was correlated with a higher clinical worsening event rate and could be an independent predictor of clinical outcomes in multivariate analysis.

Electrocardiographic abnormalities and NT-proBNP levels at long-term follow-up of patients with dyspnea after pulmonary embolism.

OBJECTIVES: Electrocardiogram (ECG) and measurement of plasma brain natriuretic peptides (BNP) are established markers of right ventricular dysfunction (RVD) in the setting of acute pulmonary embolism (PE) but their value at long-term follow-up is largely unknown. The purpose of this prospective study was to determine the prevalence of ECG abnormalities, describe levels of N-terminal proBNP (NT-proBNP), and establish their association with dyspnea at long-term follow-up after PE. DESIGN: All Swedish patients diagnosed with acute PE in 2005 (n = 5793) were identified through the Swedish National Patient Registry. Surviving patients in 2007 (n = 3510) were invited to participate. Of these, 2105 subjects responded to a questionnaire about dyspnea and comorbidities. Subjects with dyspnea or risk factors for development of chronic thromboembolic pulmonary hypertension were included in the study in a secondary step, which involved collection of blood samples and ECG registration. RESULTS: Altogether 49.3% had a completely normal ECG. The remaining participants had a variety of abnormalities, 7.2% had atrial fibrillation/flutter (AF). ECG with any sign of RVD was found in 7.2% of subjects. Right bundle branch block was the most common RVD sign with a prevalence of 6.4%. An abnormal ECG was associated with dyspnea. AF was associated with dyspnea, whereas ECG signs of RVD were not. 61.2% of subjects had NT-proBNP levels above clinical cut-off (>125 ng/L). The degree of dyspnea did not associate independently with NT-proBNP levels. CONCLUSIONS: We conclude that the value of ECG and NT-proBNP in long term follow-up after PE lies mostly in differential diagnostics.

Antegrade and Retrograde Approaches with a Mechanical Thrombectomy Device for the Treatment of Acute Lower Limb Deep Vein Thrombosis.

OBJECTIVE: To examine the efficacy of antegrade and retrograde approaches with the AngioJet thrombectomy device for the treatment of acute lower limb deep vein thrombosis (DVT) and to evaluate the necessity of filter placement. METHODS: The clinical data of patients with acute lower limb DVT treated with the AngioJet device from January 2021 to June 2023 were retrospectively analyzed. The patients were divided into the antegrade and retrograde treatment groups according to the surgical approach and the direction of valve opening. The thrombosis interception rate of the filter, incidence of pulmonary embolism (PE), thrombectomy effectiveness, venous obstruction rate, and thrombosis recurrence rate of each treatment group were evaluated. In addition, factors affecting patency were analyzed. RESULTS: AngioJet was employed for 84 patients with acute lower limb DVT, treating a total of 88 limbs. The thrombosis interception rate of the filter was 35.7% (30 patients). The incidence of new PE or PE exacerbation was 6.0% (5 patients), and a filter retrieval rate of 97.6% (82 patients) was detected. Thrombus removal of grade III occurred in 35 (64.8%) of the 54 limbs (61.4%) in the antegrade treatment group versus 13 (38.2%) of the 34 limbs (38.6%) in the retrograde treatment group (P < 0.05). At 3 months, venous patency and bleeding events involved 52 (96.3%) and 4 (7.4%) limbs in the antegrade treatment group, respectively, versus 29 (85.3%) and 2 (5.9%) in the retrograde treatment group, respectively (P > 0.05). Regression analysis was performed to determine factors that may affect 3-month patency in both groups. Statistically significant linear relationships were found between 3-month patency and thrombus removal rate [odds ratio [OR] = 0.546 (0.326, 0.916)], thrombus formation time [OR = 1.018 (1.002, 1.036)], and preoperative thrombosis score [OR = 1.012 (1.002, 1.022)] in the antegrade treatment group, as well as thrombus removal rate [0.473 (0.229, 0.977)] in the retrograde treatment group. In regression analysis of factors affecting patency in both groups and the venous clinical severity score/Villalta score, a statistically significant linear relationship was found between thrombus formation time and the venous clinical severity score in the antegrade treatment group [0.576 (0.467, 0.710)]. CONCLUSIONS: Both antegrade and retrograde approaches are safe and effective for the treatment of acute lower limb DVT. There are no differences in 3-month deep vein patency and post-thrombotic syndrome (PTS) incidence rates. Individuals with acute lower limb DVT are at high risk of thrombus shedding after treatment with AngioJet thrombectomy, and placement of a vena cava filter (VCF) is recommended for effective interception.

Identification of hemodynamically stable patients with acute pulmonary embolism at high risk for death: external validation of different models.

BACKGROUND: The optimal strategy for identification of hemodynamically stable patients with acute pulmonary embolism (PE) at risk for death and clinical deterioration remains undefined. OBJECTIVES: We aimed to assess the performances of currently available models/scores for identifying hemodynamically stable patients with acute, symptomatic PE at risk of death and clinical deterioration. METHODS: This was a prospective multicenter cohort study including patients with acute PE (NCT03631810). Primary study outcome was in-hospital death within 30 days or clinical deterioration. Other outcomes were in-hospital death, death, and PE-related death, all at 30 days. We calculated positive and negative predictive values, c-statistics of European Society of Cardiology (ESC)-2014, ESC-2019, Pulmonary Embolism Thrombolysis (PEITHO), Bova, Thrombo-embolism lactate outcome study (TELOS), fatty acid binding protein, syncope and tachicardia (FAST), and National Early Warning Scale 2 (NEWS2) for the study outcomes. RESULTS: In 5036 hemodynamically stable patients with acute PE, positive predictive values for the evaluated models/scores were all below 10%, except for TELOS and NEWS2; negative predictive values were above 98% for all the models/scores, except for FAST and NEWS2. ESC-2014 and TELOS had good performances for in-hospital death or clinical deterioration (c-statistic of 0.700 and 0.722, respectively), in-hospital death (c-statistic of 0.713 and 0.723, respectively), and PE-related death (c-statistic of 0.712 and 0.777, respectively); PEITHO, Bova, and NEWS2 also had good performances for PE-related death (c-statistic of 0.738, 0.741, and 0.742, respectively). CONCLUSION: In hemodynamically stable patients with acute PE, the accuracy for identification of hemodynamically stable patients at risk for death and clinical deterioration varies across the available models/scores; TELOS seems to have the best performance. These data can inform management studies and clinical practice.

Optimal hemodynamic parameters for risk stratification in acute pulmonary embolism patients.

Hemodynamic assessment of patients with pulmonary embolism (PE) remains a fundamental component of early risk stratification that in turn, influences subsequent monitoring and therapeutic strategies. The current body of literature and international evidence-based clinical practice guidelines focus mainly on the use of systolic blood pressure (SBP). The accuracy of this single hemodynamic parameter, however, and its optimal values for the identification of hemodynamic instability have been recently questioned by clinicians. For example, abnormal SBP or shock index may be a late indicator of adverse outcomes, signaling a patient in whom the cascade of hemodynamic compromise is already well underway. The aim of the present article is to review the current evidence supporting the use of SBP and analyze the potential integration of other parameters to assess the hemodynamic stability, impending clinical deterioration, and guide the reperfusion treatment in patients with PE, as well as to suggest potential strategies to further investigate this issue.

Clinical, Functional, and Quality-of-Life Outcomes after Computer Assisted Vacuum Thrombectomy for Pulmonary Embolism: Interim Analysis of the STRIKE-PE Study.

PURPOSE: To report the first interim analysis of the STRIKE-PE study, evaluating the safety and effectiveness of computer assisted vaccum thrombectomy (CAVT) for the treatment of acute pulmonary embolism (PE). MATERIALS AND METHODS: This prospective, international, multicenter study will enroll 600 adult patients with acute PE of ≤14 days and a right ventricle (RV)-to-left ventricle (LV) ratio of ≥0.9 who receive first-line endovascular treatment with CAVT using the Indigo Aspiration System (Penumbra, Alameda, California). Primary endpoints are change in RV/LV ratio and incidence of composite major adverse events (MAEs) within 48 hours. Secondary endpoints include functional and quality-of-life (QoL) assessments. RESULTS: The first 150 consecutive patients were treated with 12F catheter CAVT. Mean age was 61.3 years, 54.7% were men, 94.7% presented with intermediate-risk PE, and 5.3% presented with high-risk PE. Median thrombectomy and procedure times were 33.5 minutes and 70.0 minutes, respectively, resulting in a mean reduction in systolic pulmonary artery pressure of 16.3% (P < .001). Mean RV/LV ratio decreased from 1.39 to 1.01 at 48 hours, a 25.7% reduction (P < .001). Four (2.7%) patients experienced a composite MAE within 48 hours. At 90-day follow-up, patients exhibited statistically significant improvements in the Borg dyspnea scale score and QoL measures, and the New York Heart Association class distribution returned to that reported before the index PE. CONCLUSIONS: Interim results from the STRIKE-PE study demonstrate a significant reduction in pulmonary artery pressure and RV/LV ratio, a median thrombectomy time of 33.5 minutes, a composite MAE rate of 2.7%, and significant improvements in 90-day functional and QoL outcomes.

Prognostic value of the echocardiographic ratio tricuspid annular plane systolic excursion / pulmonary arterial systolic pressure in acute pulmonary embolism.

INTRODUCTION: The occurrence of death from acute pulmonary embolism (PE) is often linked to right ventricular (RV) failure, arising from an imbalance between RV systolic function and heightened RV afterload. In our study, we posited that an echocardiographic ratio derived from this disparity [RV systolic function assessed by tricuspid annular plane systolic excursion (TAPSE) divided by pulmonary arterial systolic pressure (PASP)] could offer superior predictive value for adverse outcomes compared to individual measurements of TAPSE and PASP alone. METHODS: We conducted a retrospective analysis using data from a University Hospital Centre spanning from 2017 to 2023. All individuals with confirmed PE and a formal transthoracic echocardiogram within 7 days of diagnosis were included. The primary endpoint was a composite outcome of death, hemodynamic deterioration needing introduction of inotropes or thrombolysis within 30 days. Secondary endpoints included 6 months all-cause mortality and onset of right-sided heart failure. RESULTS: Thirty-eight patients were included. Mean age was 58 ±15 years old. A male predominance was noted: 23 male patients (60.5%) and 15 female patients (39.5%). Eight patients met the primary composite endpoint while nine patients met the secondary composite endpoint. In multivariate analysis, the TAPSE/PASP ratio was independently associated with the primary outcome (OR=2.77, 95% CI 1.101-10.23, P=0.042). A TAPSE/PASP ratio <0.3 was independently associated with the secondary outcome (OR=3.07, 95% CI 1.185-10.18, P=0.034). CONCLUSION: This study suggests that a combined echocardiographic ratio of RV function to afterload is effective in predicting adverse outcomes in acute PE.

Immediate cardiopulmonary responses to consecutive pulmonary embolism: a randomized, controlled, experimental study.

BACKGROUND: Acute pulmonary embolism (PE) induces ventilation-perfusion mismatch and hypoxia and increases pulmonary pressure and right ventricular (RV) afterload, entailing potentially fatal RV failure within a short timeframe. Cardiopulmonary factors may respond differently to increased clot burden. We aimed to elucidate immediate cardiopulmonary responses during successive PE episodes in a porcine model. METHODS: This was a randomized, controlled, blinded study of repeated measurements. Twelve pigs were randomly assigned to receive sham procedures or consecutive PEs every 15 min until doubling of mean pulmonary pressure. Cardiopulmonary assessments were conducted at 1, 2, 5, and 13 min after each PE using pressure-volume loops, invasive pressures, and arterial and mixed venous blood gas analyses. ANOVA and mixed-model statistical analyses were applied. RESULTS: Pulmonary pressures increased after the initial PE administration (p < 0.0001), with a higher pulmonary pressure change compared to pressure change observed after the following PEs. Conversely, RV arterial elastance and pulmonary vascular resistance was not increased after the first PE, but after three PEs an increase was observed (p = 0.0103 and p = 0.0015, respectively). RV dilatation occurred following initial PEs, while RV ejection fraction declined after the third PE (p = 0.004). RV coupling exhibited a decreasing trend from the first PE (p = 0.095), despite increased mechanical work (p = 0.003). Ventilatory variables displayed more incremental changes with successive PEs. CONCLUSION: In an experimental model of consecutive PE, RV afterload elevation and dysfunction manifested after the third PE, in contrast to pulmonary pressure that increased after the first PE. Ventilatory variables exhibited a more direct association with clot burden.