TOPIC 5 Ventricular function Topic Contents Chamber dimensions 36 Ventricular wall thickness and mass 39 Athlete’s heart 39 Cardiac cycle 41 Haemodynamics 42 Invasive measurements 42 Pressure–volume analysis 44 Non-invasive measurements 45 Echo 45 Diastolic function 46 Left ventricular isovolumic relaxation time (IVRT) 49 PCWP estimation 49 Tei Index 49 Colour M-mode Doppler 49 Tissue Doppler 49 Left atrial parameters 51 Right atrial and right ventricular function 51 In vivo haemodynamic monitoring 52 Intrathoracic impedance monitoring 52 Radionuclide parameters of normal diastolic function 52 MVO2 exercise testing 52 Serum natriuretic peptides 53 Dilated cardiomyopathy 53 Chamber dimensions M-mode echo (parasternal short axis): Left ventricular internal diameters (LVIID): End diastole (LVIDd): 3.5–5.6 cm End systole (LVIDs): 1.9–4.0 cm Left atrial diameter (end systole): 1.9–4.0 cm Right ventricle: 0.7–2.3 cm IVC: <1.5 cm Table 5.1 Chamber volumes: Echocardiography and cardiac magnetic resonance Ventricular wall thickness and mass Echo (parasternal long axis M-mode – see Figures 5.1 and 5.2) Left ventricle (LV) Posterior LV wall thickness (PWT) in systole (cm) 0.6–1.2; Hypertrophy ≥1.2 Interventricular septum (IVS) thickness in systole (cm) 0.6–1.2; Hypertrophy ≥1.2 LV mass (g) = 1.04 x [(IVS + LVEDD + PWT)3 – LVEDD3] – 13.6 LV mass index = LV mass corrected for BSA (g/m2) Mean (95%CI) = 87 (64–109) Men > 102 g/m2 = LVH Women > 88 g/m2 = LVH RV wall thickness in systole (cm) 0.2–0.5; Hypertrophy ≥0.5 RV mass index g/m2 26 (17–34); Hypertrophy ≥35 Figure 5.1 Parasternal long-axis echocardiogram demonstrating measurement of LV septal and posterior wall thickness and end diastolic diameter. Figure 5.2 LV biometric data from normal (blue) and dilated cardiomyopathy (purple) hearts. Athlete’s heart It should be noted that highly trained athletes, particularly those competing in endurance sports, have cardiac measurements that fall outside the normal ranges quoted above. Studies suggest the majority of athletes’ measurements fall within the following values, although a small proportion of athletes have greater values, and exclusion of underlying heart disease must be determined. LA diameter: <4.5 cm LVEDD: <6.0 cm Posterior LV thickness: <1.3 cm Cardiac cycle Time intervals (see Figure 5.3) Figure 5.3 The normal cardiac cycle. (A) Schematic demonstrating the temporal relations of aortic pressure, left ventricular pressure, left atrial pressure, the phonocardiogram, the jugular venous pressure and the surface electrocardiogram during the cardiac cycle. (B) A schematic representation of left ventricular filling, ejection and isovolumic phases during the cardiac cycle. The time intervals for the cardiac cycle are sensitive to heart rate. The following values are based upon a heart rate of 70 beats per minute: Single complete cardiac cycle – duration ~ 0.9 s with HR = 70 bpm Diastole: • Isovolumic relaxation 0.08 s • Ventricular filling 0.5 s • Rapid passive filling 0.15 s • Slow passive filling 0.22 s • Atrial systole 0.13 s • Isovolumic contraction 0.05 s Systole: • Ventricular ejection 0.3 s Haemodynamics Invasive measurements Table 5.2 Intracardiac pressures Figure 5.4 Schematic of the normal pressure tracings during cardiac catheterization of the right heart (above) and left heart (below). Cardiac output calculations – Fick method Figure 5.5 The Fick equation for calculation of cardiac output from arteriovenous oxygen gradient and VO2. Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related Related posts: 10: Systemic vascular disease 9: Pulmonary vascular disorders 3: Preventative cardiology 6: Cardiac valvular structure and function Stay updated, free articles. Join our Telegram channel Join Tags: Cardiology Churchills Ready Reference Jun 5, 2016 | Posted by admin in CARDIOLOGY | Comments Off on 5: Ventricular function Full access? Get Clinical Tree
TOPIC 5 Ventricular function Topic Contents Chamber dimensions 36 Ventricular wall thickness and mass 39 Athlete’s heart 39 Cardiac cycle 41 Haemodynamics 42 Invasive measurements 42 Pressure–volume analysis 44 Non-invasive measurements 45 Echo 45 Diastolic function 46 Left ventricular isovolumic relaxation time (IVRT) 49 PCWP estimation 49 Tei Index 49 Colour M-mode Doppler 49 Tissue Doppler 49 Left atrial parameters 51 Right atrial and right ventricular function 51 In vivo haemodynamic monitoring 52 Intrathoracic impedance monitoring 52 Radionuclide parameters of normal diastolic function 52 MVO2 exercise testing 52 Serum natriuretic peptides 53 Dilated cardiomyopathy 53 Chamber dimensions M-mode echo (parasternal short axis): Left ventricular internal diameters (LVIID): End diastole (LVIDd): 3.5–5.6 cm End systole (LVIDs): 1.9–4.0 cm Left atrial diameter (end systole): 1.9–4.0 cm Right ventricle: 0.7–2.3 cm IVC: <1.5 cm Table 5.1 Chamber volumes: Echocardiography and cardiac magnetic resonance Ventricular wall thickness and mass Echo (parasternal long axis M-mode – see Figures 5.1 and 5.2) Left ventricle (LV) Posterior LV wall thickness (PWT) in systole (cm) 0.6–1.2; Hypertrophy ≥1.2 Interventricular septum (IVS) thickness in systole (cm) 0.6–1.2; Hypertrophy ≥1.2 LV mass (g) = 1.04 x [(IVS + LVEDD + PWT)3 – LVEDD3] – 13.6 LV mass index = LV mass corrected for BSA (g/m2) Mean (95%CI) = 87 (64–109) Men > 102 g/m2 = LVH Women > 88 g/m2 = LVH RV wall thickness in systole (cm) 0.2–0.5; Hypertrophy ≥0.5 RV mass index g/m2 26 (17–34); Hypertrophy ≥35 Figure 5.1 Parasternal long-axis echocardiogram demonstrating measurement of LV septal and posterior wall thickness and end diastolic diameter. Figure 5.2 LV biometric data from normal (blue) and dilated cardiomyopathy (purple) hearts. Athlete’s heart It should be noted that highly trained athletes, particularly those competing in endurance sports, have cardiac measurements that fall outside the normal ranges quoted above. Studies suggest the majority of athletes’ measurements fall within the following values, although a small proportion of athletes have greater values, and exclusion of underlying heart disease must be determined. LA diameter: <4.5 cm LVEDD: <6.0 cm Posterior LV thickness: <1.3 cm Cardiac cycle Time intervals (see Figure 5.3) Figure 5.3 The normal cardiac cycle. (A) Schematic demonstrating the temporal relations of aortic pressure, left ventricular pressure, left atrial pressure, the phonocardiogram, the jugular venous pressure and the surface electrocardiogram during the cardiac cycle. (B) A schematic representation of left ventricular filling, ejection and isovolumic phases during the cardiac cycle. The time intervals for the cardiac cycle are sensitive to heart rate. The following values are based upon a heart rate of 70 beats per minute: Single complete cardiac cycle – duration ~ 0.9 s with HR = 70 bpm Diastole: • Isovolumic relaxation 0.08 s • Ventricular filling 0.5 s • Rapid passive filling 0.15 s • Slow passive filling 0.22 s • Atrial systole 0.13 s • Isovolumic contraction 0.05 s Systole: • Ventricular ejection 0.3 s Haemodynamics Invasive measurements Table 5.2 Intracardiac pressures Figure 5.4 Schematic of the normal pressure tracings during cardiac catheterization of the right heart (above) and left heart (below). Cardiac output calculations – Fick method Figure 5.5 The Fick equation for calculation of cardiac output from arteriovenous oxygen gradient and VO2. Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window) Related Related posts: 10: Systemic vascular disease 9: Pulmonary vascular disorders 3: Preventative cardiology 6: Cardiac valvular structure and function Stay updated, free articles. Join our Telegram channel Join Tags: Cardiology Churchills Ready Reference Jun 5, 2016 | Posted by admin in CARDIOLOGY | Comments Off on 5: Ventricular function Full access? Get Clinical Tree
