Chapter 9 The Cardiovascular System

1. Chapter 9The Cardiovascular System

2. The Cardiovascular System:Examining the Heart and Blood Vessels • Overview • Anatomy of the heart and great vessels • The heart as a pump; blood pressure • Beginning the examination with the vital signs: blood pressure and heart rate • Jugular venous pressure (JVP) and pulsations; carotid pulse • Chest wall and apical impulse/PMI • Auscultation: S1 and S2; S3 and S4 • Auscultation: describing cardiac murmurs

3. The Heart and Great Vessels: Anatomy

4. Know Your Surface Landmarks • Count interspaces • Identify your ... • Midsternal line • Midclavicular line • Anterior axillary line • Midaxillary line

5. Visualize the Chambers of the Heart and Important Great Vessels • Visualize the circulation through the: • Superior and inferior vena cavas • Right atrium and the right ventricle • Pulmonary arteries • Left atrium and left ventricle • Aorta and the aortic arch

6. The Heart as a Pump:Key Points for Examining the Heart • Note the heart chambers and valves and the forward flow of blood from the right side of the heart through the pulmonary arteries and veins to the left side of the heart • Combine this knowledge with careful examination and systematic clinical reasoning • This will lead you to correct identification of valvular and congestive heart disease

7. The Heart as a Pump: The Cardiac Cycle of Systole and Diastole • Systole: the ventricles contract • The right ventricle pumps blood into the pulmonary arteries (pulmonic valve is open) • The left ventricle pumps blood into the aorta(aortic valve is open) • Diastole: the ventricles relax • Blood flows from the right atrium → right ventricle (tricuspid valve is open) • Blood flows from the left atrium → left ventricle (mitral valve is open)

8. The Heart as a Pump: Important Concepts • Preload volume overload • Contractility: ventricles contract during systole • Afterload pressure overload • Cardiacoutput: stroke volume x heart rate • Blood pressure: cardiac output x systemic vascular resistance

9. Blood Pressure • Systolic blood pressure • Pressure generated by the left ventricle (LV) during systole, when the LV ejects blood into the aorta and the arterial tree • Pressure waves in the arteries create pulses • Diastolic blood pressure • Pressure generated by blood remaining in the arterial tree during diastole, when the ventricles are relaxed

10. Beginning the Examination:The Vital Signs • First, observe the patient, then begin assessing the vital signs • Blood pressure • Select the proper size cuff • Position the patient properly • Make sure there is a brachial pulse • Apply the cuff correctly • Assess blood pressure for hypertension • Heart rate: radial vs. apical

11. Jugular Venous Pressure (JVP)and Pulsations • Recall that jugular veins reflect right atrial pressure • Steps for examination • Raise the head of the bed or examining table to 30° • Turn the patient’s head gently to the left • Identify the topmost point of the flickering venous pulsations • Place a centimeter ruler upright on the sternal angle • Place a card or tongue blade horizontally from the top of the JVP to the ruler, making a right angle • Measure the distance above the sternal angle in centimeters: a 3- to 4-centimeter elevation is normal

12. Assessing the Carotid Pulse • Keep the patient’s head elevated to 30° • Place your index and middle fingers on the right then the left carotid arteries, and palpate the carotid upstroke • Never palpate right and left carotid arteries simultaneously • The upstroke may be: • Brisk – normal • Delayed – suggests aortic stenosis • Bounding – suggests aortic insufficiency • Listen with the stethoscope for any bruits

13. Palpating the Chest Wall • Using the finger pads, palpate for heavesor lifts from abnormal ventricular movements • Using the ball of the hand, palpate for thrills, orturbulence transmitted to the chest wall surface by a damaged heart valve • Palpate the chest wall in the aortic, pulmonic, left parasternal, and apical areas

14. Assessing the Point of Maximal Impulse (PMI) • Inspect the left anterior chest for a visible PMI • Using your finger pads, palpate at the apex for the PMI • The PMI may be: • Tapping — normal • Sustained — suggests LV hypertrophy from hypertension or aortic stenosis • Diffuse — suggests a dilated ventricle from congestive heart failure or cardiomyopathy • Locate the PMI by interspace and distance in centimeters from the midsternal line • Assess location, amplitude, duration, and diameter

15. Question When examining a patient for the apical impulse (PMI), which of the following is LEAST important to assess? • Location • Amplitude • Rhythm • Diameter

16. Answer • Rhythm • Assess location, amplitude, duration, and diameter

17. Listening to the Heart — Auscultation • Listen in all 6 listening areas for S1 and S2 using the diaphragm of the stethoscope • Then listen at the apex with the bell • The diaphragm and the bell ... • The diaphragm is best for detecting high-pitched sounds like S1, S2, and also S4 and most murmurs • The bell is best for detecting low-pitched sounds like S3 and the rumble of mitral stenosis

18. Question The bell of the stethoscope is most useful for auscultating: • Diastolic murmurs • High-pitched heart sounds • Low-pitched heart sounds • Systolic clicks • Systolic murmurs

19. Answer • Low-pitched heart sounds • The bell is best for detecting low-pitched sounds like S3 and the rumble of mitral stenosis

20. Describing Heart Murmurs: Timing and Duration • Identify and describe any murmurs • Timing: are the murmurs systolic or diastolic? • Tip: palpate the carotid upstroke (occurs in systole) as you listen • If the murmur coincides with the carotid upstroke, it is systolic • Duration • Early / mid / or late systolic • Early / mid / or late diastolic

21. Describing Heart Murmurs: Shape and Intensity • Shape • Crescendo, decrescendo, or both (sometimes called diamond-shaped) • Example, crescendo-decrescendo systolic murmur of aortic stenosis Crescendo Decrescendo Both

22. Describing Heart Murmurs: Shape and Intensity (cont.) • Shape • Plateau ... machinery • Example, holosystolic murmur of mitral regurgitation • Intensity: grade the murmur on a scale of 1 to 6 • Grades 4 through 6 must have accompanying thrill Plateau Machinery

23. Describing Heart Murmurs:Quality, Pitch, and Location • Quality • Apply terms like harsh, musical, soft, blowing, or rumbling • Pitch • Apply terms like high-, medium-, or low-pitched • Examples • Harsh 2/6 medium-pitched holosystolic murmur best heard at the apex describes mitral regurgitation • Soft, blowing 3/6 decrescendo diastolic murmur best heard at the lower left sternal border describes aortic regurgitation