**1. Introduction**

214 Venous Thrombosis – Principles and Practice

Warkentin, T.E., Sikov, W.., & Lillicrap, D.P. (1999). Multicentric warfarin-induced skin

Weismann, R.E. & Tobin, R.W. (1958). Arterial embolism occurring during systemic heparin therapy. *AMA Archives of Surgery*, vol.76, no.2, (February 1958), pp.219–225. Yamamoto, S., Koide, M., Matsuo, M. Suzuki, S., Ohtaka, M., Saika, S., & Matsuo, T. (1996).

Yoon, J.H. & Jang, I.K. (2011). Heparin-induced thrombocytopenia in cardiovascular

*Hematology,* vol.62, no.1, (September 1999), pp.44-48.

*Kidney Diseases*, vol.28, no.1, (July 1996), pp.82-85.

no.3, (May-June 2011), pp.143-153.

necrosis complicating heparin-induced thrombocytopenia. *American Journal of* 

Heparin-induced thrombocytopenia in haemodialysis patients. *American Journal of* 

patients: Pathophysiology, diagnosis, and treatment. *Cardiology in Review*, vol.19,

Pulmonary infarction is localized destruction (necrosis) of lung tissue by blocking (obstruction of) the arterial blood supply. It follows an embolic event in ~10% of cases. Blockage of pulmonary artery by a clot or air bubble or other particle (called pulmonary embolism) leads to localized damage of lung tissue which results in pulmonary infarction (1, 2). The reasons for this low incidence of pulmonary infarct are the dual blood supply systems, as well as oxygenation of the lung tissues via ventilation (3).

The predisposing factors for pulmonary infarct include congestive heart failure, pleural effusion, pulmonary infection, atelectasis, hypotension, positive-pressure ventilation, chronic lung disease, central venous catheterization and an immunocompromised state. It is more common in people with chronic heart and lung diseases. Infarction condition may be mild and can be rapidly fatal (4).

Common symptoms include chest pain which may be because of difficulty in breathing, high pulse rate, mild fever, developing of fluid in the lungs, a productive cough (sputum may be blood-tinged). Blockage may also result into circulatory breakdown, like low blood pressure, presence of very little oxygen in the blood. Also, swelling of neck vein and leg, weakness, restlessness, and fainting. In the case of infection as developing complication, there is worsening of the clinical status, persistent fever, malaise, sweating, increasing pulse rate and leukocytosis (usually more than 20 x 109/l) (5).

Diseases that should be listed in the differential diagnosis include bacterial pneumonia, aspergillosis, tuberculosis, norcardia, actinomycosis, and granulomatous vasculitis. Other unusual etiologies that should be listed in the differential diagnosis include primary or metastatic angiosarcoma or leomyosarcoma and lung cancer invading the main pulmonary arteries (6,7).
