Percutaneous Thrombus Removal in COVID-19–Infected Patient with Pulmonary Embolism

We present a case describing the use of the AngioVac system (AngioDynamics, Inc.) and SENTINEL™ cerebral protection system (SCPS; Boston Scientific) in a patient with COVID-19 who initially presented with a large deep-vein thrombosis of the left lower extremity, complicated by a pulmonary embolism. Although he initially improved with systemic alteplase, he later developed a second large clot diagnosed in transit in the right atrium. Within 12 hours from initial thrombolysis, this large clot wedged across an incidental patent foramen ovale (PFO), the atrial septum, and the cavotricuspid annulus. We emergently performed a percutaneous clot extraction with preemptive placement of the SCPS in anticipation of cardioembolic phenomenon. A large (> 10 cm) clot was extracted without complication, and the patient was discharged home. The combined use of SCPS and AngioVac in this case suggests a potential role for percutaneous treatment of severe and consequential thromboembolic disease, especially in patients with a PFO, and may be considered as an alternative and less-invasive option in patients with COVID-19. While cerebral embolic protection devices are approved for and widely used in transcatheter aortic valve replacement procedures, there is a theoretical benefit for use in percutaneous thrombolectomies as well.

Thrombolytic therapy in acute venous thromboembolism

Although anticoagulation remains the mainstay of treatment of acute venous thromboembolism (VTE), the use of thrombolytic agents or thrombectomy is required to immediately restore blood flow to thrombosed vessels. Nevertheless, systemic thrombolysis has not clearly been shown to improve outcomes in patients with large clot burdens in the lung or legs as compared with anticoagulation alone; this is in part due to the occurrence of intracranial hemorrhage in a small percentage of patients to whom therapeutic doses of a thrombolytic drug are administered. Algorithms have been developed to identify patients at high risk for poor outcomes resulting from large clot burdens and at low risk for major bleeding in an effort to improve outcomes in those receiving thrombolytic therapy. In acute pulmonary embolism (PE), hemodynamic instability is the key determinant of short-term survival and should prompt consideration of immediate thrombolysis. In hemodynamically stable PE, systemic thrombolysis is not recommended and should be used as rescue therapy if clinical deterioration occurs. Evidence is accumulating regarding the efficacy of administering reduced doses of thrombolytic agents systemically or via catheters directly into thrombi in an effort to lower bleed rates. In acute deep venous thrombosis, catheter-directed thrombolysis with thrombectomy can be used in severe or limb-threatening thrombosis but has not been shown to prevent postthrombotic syndrome. Because the management of acute VTE can be complex, having a rapid-response team (ie, PE response team) composed of physicians from different specialties may aid in the management of severely affected patients.

ECG in suspected pulmonary embolism

ObjectiveTo establish the diagnostic value of prespecified ECG changes in suspected pulmonary embolism (PE).MethodsRetrospective case–control study in a district general hospital setting. We identified 189 consecutive patients with suspected PE whose CT pulmonary angiogram (CTPA) was positive for a first PE and for whom an ECG taken at the time of presentation was available. We matched these for age±3 years with 189 controls with suspected PE whose CTPA was negative. We considered those with large (n=76) and small (n=113) clot load separately. We scored each ECG for the presence or absence of eight features that have been reported to occur more commonly in PE.Results20%–25% of patients with PE, including those with large clot load, had normal ECGs. The most common ECG abnormality in patients with PE was sinus tachycardia (28%). S1Q3T3 (3.7%), P pulmonale (0.5%) and right axis deviation (4.2%) were infrequent findings. Right bundle branch block (9.0%), atrial dysrhythmias (10.1%) and clockwise rotation (20.1%) occurred more frequently but were also common in controls. Right ventricular (RV) strain pattern was significantly more commonly in patients than controls, 11.1% vs 2.6% (sensitivity 11.1%, specificity 97.4%; OR 4.58, 95% CI 1.63 to 15.91; p=0.002), particularly in those with large clot load, 17.1% vs 2.6% (sensitivity 17.1%, specificity 97.4%; OR 7.55, 95% CI 1.62 to 71.58; p=0.005).ConclusionAn ECG showing RV strain in a breathless patient is highly suggestive of PE. Many of the other ECG changes that have been described in PE occur too infrequently to be of predictive value.

Containing a Clot in the Mid-Basilar Artery Using a Self-Expandable Stent to Prevent Distal Clot Migration during Intra-Arterial Thrombolysis

During local intra-arterial thrombolysis (LIT), management of the secondary embolization of a fragmented or dislodged clot can be cumber-some. The fate could be dismal if without pursuit and lysis of the migrated clot. Recently, we successfully managed a patient with acute ischemia due to a large clot impinged in the mid basilar trunk while avoiding distal migration of the clot by containing the impinged clot using a self-expandable stent during LIT.