Page 28 - Clinical Pearls in Cardiology

16 Clinical Pearls in Cardiology

25. What are the common nonsystemic causes of bilateral
pedal edema?
Bilateral pedal edema usually signifies a systemic cause
like cardiac or renal failure, hypothyroidism, etc. The
common nonsystemic causes of bilateral pedal edema
are the following:
• Obesity: Due to obstructed lymphatics or deep
venous insufficiency.
• Idiopathic edema: In young females
• Tight undergarments
• Lipid edema: Fat deposition in the ankles (seen in
obese women)
• Pelvic tumors: Centrally located tumors obstruct the
venous return from both the lower limbs (fibroid
uterus, bladder neoplasms, etc.).
26. What is the pathophysiology behind paroxysmal
nocturnal dyspnea?
Paroxysmal nocturnal dyspnea (PND) is the occurrence
of dyspnea at night during sleep. It commonly occurs
after two to three hours of sound sleep (unlike the more
severe orthopnea, in which dyspnea occurs immediately
on lying down). PND is usually associated with sweating,
wheezing and coughing. PND is relieved by assuming
upright position for about 5 to 15 minutes.
The blood that is accommodated in the large
capacitance vessels of the lower extremities is
redistributed to the cardiopulmonary system upon
assuming the recumbent position. This redistributed
blood increases the end diastolic volume. A normal heart
can handle this extra volume by increasing the force of
cardiac contraction according to the Frank–Starling law
(the Frank–Starling law states that the force of cardiac
contraction is directly proportional to the end diastolic