cardiovascular disorders
Cardiovascular Examination
Veins
The peripheral veins are observed for Varicose Veins , arteriovenous malformations (AVMs), and shunts, and for overlying inflammation and tenderness due to thrombophlebitis. An AVM or a shunt produces a continuous murmur (heard on auscultation) and often a palpable thrill (because resistance is always lower in the vein than in the artery during systole and diastole). The neck veins are examined to estimate venous wave height and waveform. Height is proportional to right atrial pressure, and waveform reflects events in the cardiac cycle; both are best observed in the internal jugular vein. . The top of the venous column is normally just above the clavicles (upper limit of normal: 4 cm above the sternal notch in a vertical plane). The venous column is elevated in Heart Failure (HF) , 3 cm) during abdominal pressure in disorders that cause a dilated and poorly compliant RV or in obstruction of RV filling by Tricuspid Stenosis or right atrial tumor. Normally, the venous column falls slightly during inspiration as lowered intrathoracic pressure draws blood from the periphery into the vena cava. A rise in the venous column during inspiration (Kussmaul sign) occurs typically in chronic Pericarditis , right ventricular Jugular vein waves (see figure Normal jugular vein waves ) can usually be discerned clinically but are better seen on the screen during central venous pressure monitoring. Theawave is caused by right atrial contraction (systole) and is followed by thexdescent, which is caused by atrial relaxation. Thecwave, an interruption of thexdescent, is caused by the transmitted carotid pulse; it is seldom discerned clinically. Thevwave is caused by right atrial filling during ventricular systole (tricuspid valve is closed). Theydescent is caused by rapid filling of the right ventricle during ventricular diastole before atrial contraction. waves disappear in atrial fibrillation and are accentuated when RV compliance is poor (eg, in Pulmonary Hypertension or 