…tone) and decreases during expiration (due to increased vagal tone). This results in a slightly irregular rhythm. Sinus arrhythmia occurs in the majority of healthy…

…rhythm except from the fact that the rhythm is slightly irregular ( Figure 1 ). This is mostly a normal (physiological) finding, particularly among young and healthy…

…of expiration. It provides an integrated view of ventilation , metabolism , and perfusion . Carbon dioxide, a byproduct of aerobic metabolism, is transported from the tissues back…

…at the level of the individual: it does not distinguish muscle from fat and takes no account of fat distribution. Waist circumference and the waist…

…only investigation that distinguishes obstructive from restrictive impairment of lung function, and COPD cannot be diagnosed without it . The quality of the test determines its…

…flow in the retrograde direction (from the atrium to the inferior vena cava). In constrictive pericarditis, the E wave velocity varies during inspiration and expiration…

…and clinically distinct complications of acute myocardial infarction (AMI): Early infarct associated pericarditis , which develops from several hours to approximately 4 days after infarction and…