Cardiac Pump Failure and Hemodynamics PDF

Cardiac Pump Failure and Hemodynamics Lecture prepared by : Ricardo Rodriguez-Millan M.D. Harvey Mayrovitz PhD Assistant Professor Professor Department of Med...

Cardiac Pump Failure and Hemodynamics Lecture prepared by : Ricardo Rodriguez-Millan M.D. Harvey Mayrovitz PhD Assistant Professor Professor Department of Medical Education Department of Medical Education [email protected] [email protected]  Pump Failure à Heart Failure: Overview PUMP FAILURE May develop rapidly (‘Acute’) Systolic M.I. Failure Infection Myocardial Post bypass surgery Damage May develop over Time (‘Chronic’) Coronary Pressure overload as with: Artery hypertension (HTN) aortic Disease stenosis (AS) Can’t Fill Volume Overload as with: Ischemia aortic regurgitation (AR) Enough mitral regurgitation (MR) Necrosis/ Diastolic Fibrosis Failure Adaptive Remodeling Ventricular Hypertrophy Diminished Chamber Dilation Function Failure to relax properly Structural Stiffness Functional Decline Low Chamber Compliance Dr HN Mayrovitz 2 of 29 Cardiac Valve Conditions Affecting Pump Function Aortic Stenosis Pressure “overload” Mitral Stenosis LVP LAP Aortic Insufficiency (Regurgitation) Volume “overload” Mitral Insufficiency (Regurgitation) LV LA PA = Pulmonary artery pressure PV = Pulmonary vein pressure MAP = Mean aortic pressure CVP = Central venous pressure RAP = Right atrial pressure LAP = Left atrial pressure LVP = Left ventricular pressure RVP = Right ventricular pressure Dr HN Mayrovitz 3 of 29  Aortic Stenosis Outflow obstruction Systolic Velocity Increase + Ventricle Pressure Systolic + Pressure Loss Murmur Decreased Gradient=LVP-ABP Stroke Volume Outflow obstruction summary Older Age Aortic Stenosis (+) Valve Resistance and (+) LVP Calcification Increased Resistance (-) SV and (-) SBP and (-) d(ABP)/dt Rheumatic LA During Systole + LVP predisposes to LVH Fibrosis RA Slowed Peripheral pulse weak and non- Calcification LV rate of RV of rise crisp on palpation Reduced valve area with high flow Stenotic (CO) causes high Reynold’s number Q à systolic murmur DP LARGE High flow combined with small orifice causes high velocity and turbulence Dr HN Mayrovitz 4 of 29  Aortic Stenosis: Mild vs. Severe LVP LVP (+) LVP (-) ABP (+) Gradient ABP (-) d(ABP)/dt ABP Mild Severe Dr HN Mayrovitz 5 of 29 Interactive Question In the early stages of a hemodynamically significant aortic stenosis, which one of the following pressures increases first? A) RAP B) CVP C) MAP D) LAP E) PA Dr HN Mayrovitz 6 of 29 Interactive Question In the presence of a hemodynamically significant aortic stenosis, which one of the following pressures would decrease? A) RAP B) CVP C) MAP D) LAP E) PA Dr HN Mayrovitz 7 of 29 Interactive Question Bill is a 72-year-old gentleman with a history of aortic stenosis and significant arterial hypertension. He is complaining of breathing difficulties. An elevation in which one of the following pressures most directly contributes to his symptom? A) RAP B) CVP C) MAP D) LVP E) PV Dr HN Mayrovitz 8 of 29  Mitral Stenosis Inflow obstruction Diastolic velocity increase Mitral Stenosis Diastolic Increased Inflow obstruction summary LA R During Murmur Diastole + Valve resistance and + LAP Rheumatic Carditis RA + LAP predisposes to Fibrosis LV Calcification à LA enlargement and RV volume increase à Atrial Arrhythmias à Pulmonary edema Severity measurable via the LAP – LVP gradient Since ventricular filling is during diastole, the stenosis causes a diastolic murmur + LAP to overcome +R Dr HN Mayrovitz 9 of 29  Aortic Insufficiency – Regurgitation (AR) Low R 1) If aortic valve is normal and closes normally what determines: how fast ABP falls? to what level it falls? Normal AR TPR and C are main factors affecting ABP fall 3) What happens if the valve fails to close normally? 2) If TPR increases, what would you expect to happen to diastolic pressure? 4) What accounts for the increased Systolic Pressure? +Preload→ + SV 80 mmHg Low TPR Higher TPR Dr HN Mayrovitz 10 of 29 Aortic Insufficiency – Regurgitation: Summary Diastolic backflow Diastolic velocity increase Diastolic Murmur Aortic Insufficiency summary Aortic valve does not close fully during diastole Backflow from aorta to LV as long as ABP >LVP Backflow During This low resistance pathway LA Diastole causes a rapid decline in ABP Effective SV is compromised RA LV Ventricle will hypertrophy (LVH) as it tries to RV compensate for “lost” effective SV Reduced valve area causes increased NR during backflow Diastolic murmur! Dr HN Mayrovitz 11 of 29  Mitral Insufficiency - Regurgitation Systolic backflow Systolic Murmur Aorta Aorta ~Normal High LAP LAP Mitral Insufficiency Summary Effect depends on if acute or slowly developing Acute Chronic Acute (e.g. rupture of the chordae tendineae) causes volume to enter atrium during systole Result is increase in LAP since no adaption of atrial size to accommodate increased volume Causes LAP Chronic, that develops over time permits to increase atrium to adjust to accommodate added volume with a lessor increase in LAP Dr HN Mayrovitz 12 of 29  Interactive Question The figure shows hemodynamic measurements in a 62-year-old patient with a childhood history of rheumatic fever. 1) Which of the following cardiac valve conditions is most likely present? A) Mitral stenosis B) Aortic stenosis 2) His gradient is closest to which of the C) Aortic regurgitation following values in mmHg? D) Aortic insufficiency A) 50 E) Mitral regurgitation B) 75 C) 100 D) 150 E) 200 Dr HN Mayrovitz 13 of 29 Interactive Question Jill is a 68-year-old retired nurse who presents with significant bilateral ankle edema (swelling) and breathing difficulties on exertion. An elevation in which one of the following pressures most directly contributes to her ankle edema? A) LAP B) CVP C) MAP D) LVP E) PV Dr HN Mayrovitz 14 of 29 Impact of Valve Dysfunction on P-V Loops Dr HN Mayrovitz 15 of 29  Aortic Stenosis: P-V LOOPS Aortic Stenosis Increased No change in Resistance LA During contractility Systole RA in this example LV 200 RV LVP greater To sustain AORTIC STENOSIS LV Pressure (mmHg) Blood flow Increased outflow R causes increase in effective afterload 100 LVP greater To open SV & EF are reduced Aortic Valve LV pressures are elevated and don’t Can’t empty represent aortic Normal as much pressure as they 0 normally would 0 50 100 150 LV Volume (ml) 16 of 29 Dr HN Mayrovitz  P-V LOOPS: Mitral Stenosis (MS) Mitral Stenosis Increased LA R During 200 Diastole MITRAL STENOSIS RA Reduced LV filling LV Pressure (mmHg) LV due to increased R RV Decreased EDV Decreased EDV 100 Decreased ESV But reduced SV and reduced EF 0 0 50 100 150 200 LV Volume (ml) Dr HN Mayrovitz 17 of 29  P-V LOOPS: Mitral Regurgitation (MR) 200 Systolic backflow MITRAL REGURGITATION into Left Atrium (LA) During ventricle LV Pressure (mmHg) Elevated LAP contraction transmitted to LV some LV volume during filling lost to atrium EDV is increased 100 Adaptation over time to compensate Aorta Aorta ~Normal for lost EFFECTIVE High LAP LAP SV further increases EDV Acute Chronic No isovolumic contraction or relaxation 0 0 50 100 150 200 During relaxation LV Volume (ml) Looks like greater SV MV not fully closed It is – but not into aorta Some LV volume lost to LA Dr HN Mayrovitz 18 of 29  P-V LOOPS: Aortic Regurgitation (AR or AI) AORTIC REGURGITATION Regurge during diastole 200 increases EDV and ESV Chronic To LV Pressure (mmHg) Backflow During CHF Diastole LA RA Until LV 100 LVP > ABP RV Backflow Into LV Relaxation & Contraction NOT isovolumic Normal Acute Remodeling over time adds to EDV increase 0 Prior cycle (eccentric hypertrophy) 0 Backflow 50 100 150 Regurgitation creates Volume LV Volume (ml) abnormally Enters LV large EDV ABP > LVP Dr HN Mayrovitz 19 of 29 Adaptations and Remodeling Dr HN Mayrovitz 20 of 29  Adaptations / Remodeling + Afterload HYPERTROPHY + Preload more force chamber expands needed to to accommodate overcome larger volume greater load Concentric Normal Eccentric + Muscle Mass Mass & + Chamber Size AS or HTN Volume MR or AR Dr HN Mayrovitz 21 of 29  Summary of Systolic Dysfunction Systolic Dysfunction -Myocardial Contractility Impaired Contraction -SV Intrinsic dysfunction Loss of Viable of contractile Contracting apparatus Muscle +EDV e.g. - inotropy e.g. M.I. +EDP IF LV involved: à initially pulmonary congestion & edema IF RV involved:à initially peripheral edema and ascites Dr HN Mayrovitz 22 of 29  Summary of Diastolic Dysfunction Diastolic Dysfunction -Ventricle Compliance Reduced removal rate - EDV + EDP Reduced lusitropy or amount of Ca++ from SR during diastole Hypertrophy Pulmonary - SV Structural Changes + Muscle mass Congestion + Wall Thickness + Tissue fibrosis Dr HN Mayrovitz 23 of 29 Interactive Hemodynamic Questions Dr HN Mayrovitz 24 of 29  Interactive Questions: What is Cardiac Valve Condition? A. Normal B. Mitral Stenosis C. Mitral Regurgitation D. Aortic Regurgitation E. Aortic Stenosis LVP ABP Dr HN Mayrovitz 25 of 29  Interactive Questions: What is Cardiac Valve Condition? A. Normal B. Mitral Stenosis C. Mitral Regurgitation D. Aortic Regurgitation E. Aortic Stenosis LVP LAP Dr HN Mayrovitz 26 of 29  Interactive Questions: What is Cardiac Valve Condition? A. Normal B. Mitral Stenosis C. Mitral Regurgitation D. Aortic Regurgitation LVP E. Aortic Stenosis LAP Dr HN Mayrovitz 27 of 29  Interactive Questions: What is Cardiac Valve Condition? A. Normal B. Mitral Stenosis C. Mitral Regurgitation D. Aortic Regurgitation LVP E. Aortic Stenosis LAP Dr HN Mayrovitz 28 of 29  Interactive Questions: What is Cardiac Valve Condition? A. Normal B. Mitral Stenosis C. Mitral Regurgitation D. Aortic Regurgitation E. Aortic Stenosis LVP ABP Dr HN Mayrovitz 29 of 29