Clot-in-transit: A ticking time bomb in the heart with serious consequences

Clot-in-transit and pulmonary embolism: an urgent call for awareness and action

Patients with acute pulmonary embolism (PE) have a wide spectrum of clinical presentations, from incidental findings to sudden cardiac death. Management and treatment recommendations in currently available guidelines vary according to patient risk and haemodynamic profile. A clot-in-transit (CiT) in the right heart chambers may be occasionally identified and is, therefore, an under-recognised but challenging condition, often preceding an abrupt clinical deterioration, and associated with increased mortality. Data on the detection of a CiT are sparse but consistent in attributing negative prognostic relevance, and therefore the presence of CiT should be systematically investigated and recorded in the setting of PE.In this review, the challenges related to the identification of a CiT are highlighted. Here, we propose an algorithm where the role of the Pulmonary Embolism Response Team (PERT) is reinforced. The PERT should convene once the CiT is suspected, to define the timeline for the diagnostic steps and subsequent management on a case-by-case basis. A patient with PE and CiT requires close bedside monitoring and rapid escalation therapy in case of clinical deterioration. Beyond anticoagulation alone, more aggressive strategies can be considered, including systemic thrombolysis, surgical pulmonary embolectomy and the currently emerging catheter-directed therapies. PROSPERO registration number: CRD42024493303.

Dizziness, Light-Headedness or A Clot-In-Transit: Obtaining a History and Physical Examination is Both a Science and an Art

Introduction

Venous thromboembolism (VTE) rarely presents with dizziness as the primary complaint, which can delay diagnosis. We report a rare case of dizziness as the chief complaint for a clot-in-transit and extensive bilateral pulmonary emboli.

Case description

A 70-year-old woman presented to the emergency room (ER) with dizziness and a fall, without reporting loss of consciousness. Her symptoms included positional dizziness, tinnitus and visual darkness, alongside prior exertional fatigue and dull chest pressure. Despite a history of left leg oedema and inconsistent use of medications for hypertension and diabetes, initial examinations suggested vestibular neuritis and decompensated heart failure, confirmed by echocardiogram findings and response to prednisone. While hospitalised, she experienced pre-syncope after showering, initially deemed vasovagal. However, exertional hypotension led to further investigation, revealing right heart strain. Ultrasound identified a left popliteal deep vein thrombosis, and a computed tomography (CT) angiogram confirmed extensive bilateral pulmonary emboli with right heart strain. Cardiology discovered large, mobile thrombi in transit in the heart, necessitating an urgent mechanical thrombectomy. Following treatment, her pulmonary pressure improved, and she was discharged on anticoagulation medicine. One month later, an echocardiogram showed normalised heart function.

Conclusion

This case highlights the importance of differentiating dizziness from pre-syncope, as exertional pre-syncope can indicate an obstructive physiology such as VTE. Cognitive bias can obscure diagnosis in atypical presentations. A pulmonary embolism response team could improve management of these cases, where prompt diagnosis and treatment are essential for favourable outcomes.

LEARNING POINTS

Cognitive bias should be consistently challenged while ruling out pulmonary emboli based on the absence of typical signs.It is essential to differentiate vertigo from light-headedness or pre-syncope in patients presenting with a complaint of dizziness.Pre-syncope can be an important presenting complaint of haemodynamically significant pulmonary emboli and clots in transit.

Successful surgical treatment of impending paradoxical embolism with pulmonary embolism and myocardial infarction

BACKGROUND

Paradoxical embolism is a rare cause of acute arterial occlusion. This phenomenon arises when embolic material travels from the venous system crosses an abnormal shunt such as patent foramen ovale, atrial septal defects, ventricular septal defects, or pulmonary arteriovenous malformations, into the arterial system. Impending paradoxical embolism refers to the presence of an entrapped thrombus in the patent foramen ovale.

CASE PRESENTATION

We report a case of a 68-year-old female patient who presented with an impending paradoxical embolism, alongside both concomitant pulmonary embolism and myocardial infarction with ST-segment elevation. Swiftly addressed through emergency cardiac surgery and systemic anticoagulation, the patient's condition was effectively treated.

CONCLUSIONS

While the ideal treatment strategy for impending paradoxical embolism remains a topic of debate due to limited and inconclusive evidence, emergent open surgery should be contemplated in patients as it signifies a critical clinical emergency.