Bangladesh Crit Care J March 2020; 8 (1): 61-63

Clinical Image

Saddle Embolism in the Pulmonary Artery Bifurcation:

Massive Pulmonary Embolism
Md Atiquzzaman1*, Mohammad Omar Faruq2, Kazi Nuruddin Ahmed3, Md Ashikuzzaman Sohan4, Rifat
Zaman4, Farzana Akhtar5

A 60-year-old smoker, hypertensive and diabetic male

presented to the emergency department of a multidisciplinary
hospital in Dhaka with complaints of severe shortness of
breath for 2 hours and chest pain for 3 hours. Initial clinical
examination revealed respiratory rate–28/min,
pulse–120/min, blood pressure–80/50 mm of Hg, SpO2–88%
with O2 10 L/min and bilateral scattered wheeze in both lung
field. No other significant finding was noted, and he was
immediately shifted to intensive care unit (ICU) for further
management. Immediate chest X-ray was normal, hematology
& biochemistry were non-remarkable, ECG–sinus
tachycardia with right ventricular strain pattern. Cardiac
bio-markers were also normal, there was metabolic acidosis
and respiratory alkalosis with moderate hypoxemia in arterial
blood gas (ABG) analysis, D-dimer was elevated (positive in
qualitative measurement). Based on these, with a presumed
diagnosis of pulmonary embolism, computed tomographic
pulmonary angiography (CTPA) was done which reveled
almost total occlusion at pulmonary artery bifurcation (Image
1 & 2). Color Doppler echocardiogram showed dilated right Image 1: Arrows in 2D axial CTPA images point to a saddle
ventricle and moderate pulmonary arterial hypertension. embolism in the pulmonary artery bifurcation.
Immediate anticoagulation with unfractionated heparin
followed by streptokinase thrombolysis owing to
hemodynamic instability (requiring inotrope support). He also
required mechanical ventilation. The patient expired on the
following day.

1. Senior Clinical Staff, General ICU, Asgar Ali Hospital,

Dhaka-1204, Bangladesh.
2. Professor & Chief Consultant, General ICU and Emergency, United
Hospital Ltd., Dhaka-121, Bangladesh.
3. Specialist, General ICU, Asgar Ali Hospital, Dhaka-1204,
Bangladesh.
4. Senior Resident Medical Officer, General ICU, Asgar Ali Hospital,
Dhaka-1204, Bangladesh.
5. Senior Medical Officer, Department of Obst. & Gynae, OGSB
Hospital & Institute of Reproductive & Child Health, Dhaka,
Bangladesh. Image 2 A, B & C: Arrows in 2D CTPA images showing
*Corresponding Author:
filling defect (large thrombus) in the pulmonary artery.
Dr. Md. Atiquzzaman
MBBS
DISCUSSION
Senior Clinical Staff, General ICU, Asgar Ali Hospital
111/1/A, Distillery Road, Gandaria, Dhaka-1204, Bangladesh. Pulmonary embolism (PE) is a common and potentially fatal
E-mail: drazrinku@gmail.com disease, especially among the elderly but is still
Contact: +8801711939036
underdiagnosed1,2,6. Incidence rate increases exponentially

Received : December 10, 2019; Accepted : February 20, 2020 61

Bangladesh Crit Care J March 2020; 8 (1): 61-63
with age for both men and women. The overall age-adjusted observed morphological and Doppler abnormalities may
incidence rate is higher for men (114 per 100000) than women result from acute pulmonary hypertension: dilatation of the
(105 per 100000), male: female sex ratio is 1.2:1. Incidence right heart chambers, a very sensitive and reliable sign of
rate is somewhat higher in women during the childbearing severe pulmonary embolism when the ratio of the right/left
years. For almost one-quarter of PE patients, the initial ventricular dimension > 0.6, abnormal interventricular septal
clinical presentation is sudden death1. The majority of PE contraction, a very specific sign of massive pulmonary
arise from the propagation of lower limb deep vein embolism, and increased systolic pulmonary artery pressure.
thrombosis. Rare causes include septic emboli (from Echocardiography is extremely helpful in differential
endocarditis affecting the tricuspid or pulmonary valves), diagnosis and assessment of circulatory collapse3,11. CTPA is
tumor (especially choriocarcinoma), fat emboli following the gold standard diagnostic test 6,7. Nephrotoxicity and
fracture of long bones, air, and amniotic fluid - which may history of allergy to contrast media limits it’s use. In these
enter mother’s circulation following delivery3,7. Risk factors cases, ventilation–perfusion (V/Q) scanning or
convincingly demonstrated include male gender, increasing ventilation-perfusion single photon emission computed
patient age and body mass index, major surgery, prolonged tomography (V/Q SPECT) may be considered. Duplex
immobility, hospital or nursing home confinement, active ultrasound or Venogram of leg veins may demonstrate the
cancer with or without concurrent chemotherapy, multiple source3,7. Prompt recognition and treatment potentially
trauma, chronic heart failure, central vein catheterization or life-saving. Adequate oxygenation, maintenance of
transvenous pacemaker, prior thrombosis, varicose veins, circulation with intravenous fluids or plasma expander and
neurological disease with leg paresis and few hematological alleviation of symptoms with opiates is immediate focus.
conditions; patients with chronic liver disease have a reduced Main principle of treatment is anticoagulation. Inferior vena
risk1,5. A recognized risk factor is present in 80-90% 3. Clinical caval filters may be used in patients in whom anticoagulation
presentation is non-specific, depends on number, size and is contraindicated or recurrent thromboembolism despite
distribution of emboli and on underlying cardiorespiratory anticoagulation. Thrombolysis or surgical pulmonary
reserve3,7. Most patients with PE feature at least one of four embolectomy is indicated in patients with acute massive PE
symptoms which, in decreasing order of frequency, are accompanied by cardiogenic shock3. The risk of recurrence is
sudden onset dyspnea, chest pain, fainting (or syncope), and high. So, persons at risk for venous thromboembolism must
hemoptysis. The occurrence of such symptoms, if not first be identified1,3.
explained otherwise, should alert the clinicians to consider PE
PE remains a disease which requires high clinical suspicion.
in differential diagnosis, and order the appropriate objective
Unlike other conditions, no specific symptoms, signs or
test6. The patients with suspected pulmonary embolism must
investigations reflect a disease process immediately. Hence
undergo some diagnostic tests until the diagnosis is
patients presenting with acute onset of dyspnea should be
ascertained or eliminated or an alternative diagnosis is
evaluated for common cause of dyspnea but pulmonary
confirmed. The simplified Well’s pre-test probability scoring
embolism should be kept in mind, so as not to miss this fatal
algorithm for pre-investigation evaluation of PE is a
disease.
commonly utilized and validated assessment tool4. An
elevated D-dimer is of limited value, as it may be raised in a
variety of other conditions, including myocardial infarction,
pneumonia and sepsis. However, low levels, particularly in
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