Cardiac Pathophysiology & Intervention II PDF

Cardiac Pathophysiology & Intervention II Heidi Tymkew PT, DPT, MHS, CCS Cardiomyopathy (CM) Cardiomyopathy (CM) 3 main types: Dilated Hypertrophic Restrictive  Dilated Cardiomyopathy (DCM) ▪ Characterized by enlargement of the heart chambers...

Cardiac Pathophysiology & Intervention II Heidi Tymkew PT, DPT, MHS, CCS Cardiomyopathy (CM) Cardiomyopathy (CM) 3 main types: Dilated Hypertrophic Restrictive  Dilated Cardiomyopathy (DCM) ▪ Characterized by enlargement of the heart chambers ▪ Impairs pumping ability -> Decreases SV and CO ▪ Possible causes of DCM: CAD/MI, ETOH abuse, systemic HTN, DM, viral infections, toxins, pregnancy, drugs ▪ Can be idiopathic (Merck Manual, 2021) Dilated Cardiomyopathy (DCM) Hypertrophic Cardiomyopathy (HCM) ▪ Characterized by LV hypertrophy and rigid ventricular wall, and reduction in chamber size ▪ Decreased stroke volume and cardiac output ▪ Often genetic ▪ Most common type of CM ▪ Often asymptomatic and undiagnosed ▪ Can cause sudden death in young athletes (Merck Manual, 2021)  Hypertrophic Cardiomyopathy (HCM) ▪ 2 Types Treatment: ▪ Obstructive HCM ▪ Medical: ▪ Nonobstructive HCM ▪ Mavacamten (Camzyos) – cardiac myosin inhibitor ▪ Symptoms ▪ Other cardiac meds ▪ Asymptomatic ▪ Surgical: ▪ Heart failure symptoms (SOB, ▪ Septal myectomy fatigue, LE edema etc) ▪ Alcohol septal ablation ▪ Implantation cardiac devices ▪ Heart transplant  Restrictive Cardiomyopathy ▪ Least common CM ▪ Characterized by marked endocardial scarring (fibrosis) → impairs diastolic filling (↓ CO) ▪ Unknown cause ▪ Risk factors ▪ Sarcoidosis ▪ Connective tissue disorders ▪ Some cancer treatments (XRT/chemo) ▪ Symptoms: Heart failure symptoms ▪ Treatments: No specific interventions, manage symptoms and treat underlying cause (Merck Manual, 2021) Heart Failure  Heart Failure Chronic, progressive condition in which the heart muscle is unable to pump enough blood to meet the body’s needs for blood and oxygen (↓ Cardiac Output) Often accompanied by shortness of breath and fatigue (Journal of Cardiac Failure 2023 291412-1451) (Journal of Cardiac Failure 2023 291412-1451)  Prevalence of Heart Failure in the US by Age Tsao et al. Circulation. Heart Disease and Stroke Statistics—2023 Update: A Report From the American Heart Association, Volume: 147, Issue: 8, Pages: e93-e621, DOI: (Journal of Cardiac Failure 2023 291412-1451)  Heart Failure Mechanisms of Heart Failure (Lilly L: Pathophysiology of heart disease, ed 6, Philadelphia, 2015, Lippincott Williams & Wilkins) Types of Heart Failure Right Heart Failure - Venous congestion - Systemic symptoms Left Heart Failure - Reduced cardiac output - Pulmonary symptoms Left HF often leads to Right HF  Jugular Venous Distention (JVD) ▪ Indication of increased volume in the venous system or right- sided heart failure ▪ In the supine position with head of bed at least 45 degrees and instruct them to turn their head to the left JVD is said to be present if the veins distend above the clavicles  Main Causes of Heart Failure Left-sided HF Right-sided HF ▪ CAD (Left ventricle MI) ▪ CAD (Right ventricle MI) ▪ HTN ▪ COPD ▪ Valvular heart disease ▪ Pulmonary HTN ▪ Cardiomyopathy ▪ Pulmonary valve stenosis ▪ Myocarditis ▪ PE ▪ Tricuspid regurgitation Ejection Fraction (EF) = percentage of blood that leaves the heart each time is contracts ▪ Normal EF 55-75% Systolic HF = HFrEF (reduced EF) ▪ Impaired contraction/pumping ▪ Enlarged dilated heart within the myocardium ▪ Often have EF < 40% Diastolic HF = HFpEF (preserved EF) ▪ Impaired filling/relaxation ▪ Ventricular wall hypertrophy ▪ Often have EF > 50%  Decompensated Heart Failure ▪ Sudden or gradual onset of the signs/symptoms of heart failure that requires an unplanned office visit, ER visit, or hospitalization ▪ Range from mild to life-threatening ▪ Increase in edema, dyspnea, and weight gain ▪ Most of the hospital admissions for heart failure are due to decompensated heart failure ▪ 40-50% of these hospitalization have no known cause, the remainder are due to noncompliance with medications or dietary restrictions, uncontrolled HTN, ischemia, arrhythmias or COPD  Diagnosis of Heart Failure ▪ Symptoms Clinical History Physical Assessment ▪ Lab findings ▪ BNP > 400 pg/mL3 EKG ▪ NT-ProBNP > 900 pg/mL Labs (BNP) ▪ Imaging – Chest x-ray, Echocardiogram Imaging - Chest x-ray, Echo, Stress Test ▪ EKG Dx with Heart Failure ▪ Stress test  New York Heart Association (NYHA) Stages ACC/AHA Classification Heart Failure  Treatment of Heart Failure Lifestyle modifications – Exercise, healthy diet (↓ sodium), ↓ water intake, weight loss Pharmacologic treatment ▪ ↓work of heart, reduce edema, increase CO ▪ Angiotensin system blockers (ACE Inhib/ARB) ▪ Diuretics ▪ Beta blockers ▪ Inotropes (more severe HF) Benefits of Exercise Training  PT Assessment (Specific for HF) Assess for symptoms of heart Assess vital signs at rest and failure with activity Fatigue, dyspnea, orthopnea, PND ↓ or blunted SBP response with JVD activity could indicate ↑ HF/LV Weight gain dysfunction Edema – LE/hands, abdominal ↓ HR with activity could indicate area ischemia or LV dysfunction Skin color Low pulse pressure (SBP-DBP) may indicate heart failure/low SV Lung auscultation – inspiratory crackles (pulmonary edema) Monitor for signs of exercise intolerance Heart Sounds – S3  PT Assessment (Specific for HF) Assessment of aerobic/exercise capacity Individuals with heart failure often have low aerobic capacity 6 Minute Walk Test Specific protocol - 30-meter hallway; Monitor HR, BP and SpO2 (ATS, 2002) Found to be a reliable and valid test for heart failure (Int J Cardiol, 2017) 6 MWD of < 300 meters → poor prognosis MCID = 32 meters (Cardiopulm Phys Ther, 2013) (PTJ, 2020)  Exercise and Heart Failure (Arch Phys Med Rehabil, 2018; JACC Heart Fail, 2019; Medicine 2021; JACC, 2021)  Frequency – Minimum 3 days/week, prefer 5 days FITT for Heart Failure Intensity – Start at 40-50% and progress to 70-80% of HHR – Aerobic Exercise - If exercise testing if not available, then target (ACSM, 11th Ed) HR should be set 20-30 beats above resting HR and a RPE of 11-14 - Titrate based on perceived exertion - If a-fib is present, use RPE 11-14 or talk test Time – Progressively increase to 20-60 min/day Type – Aerobic exercise, focusing on treadmill or overground walking, and stationary cycling as capable; Consider interval training with deconditioned patients FITT for Heart Failure ▪ Frequency – 1-2 nonconsecutive – Resistance Exercise days (ACSM, 11th Ed) ▪ Intensity – Begin at 40% 1RM for upper body and 50% 1RM for lower body exercises and gradually increase to 70% 1RM over several weeks to months ▪ Time – 1-2 sets of 10-15 reps focusing on major muscle groups ▪ Type – Weight machines, dumbbells, elastic bands and/or body weight can be used  Watch for weight gain > 2-3 pounds/day and note any LE edema Don’t exercise in supine Monitor vital signs, breath/heart sounds Tips for and notice any signs and symptoms of Treating intolerance Patients with HF Initiate exercise at a lower intensity 40- 50%, may need even a lower intensity for patients with very low EF Assess cognition and the patient’s self management skills Education for Heart Failure ▪ Disease process ▪ Benefits of exercise ▪ Self monitoring techniques ▪ Signs of exercise intolerance ▪ Positioning ▪ Energy conservation/Pacing ▪ Home exercise program How would you treat a patient with Heart Failure? Acute Care Setting Outpatient Setting What would you want to monitor closely? Medical Interventions Treatment for ▪ CABG/Valve surgery ▪ Cardiac Resynchronization Heart Failure Therapy (CRT) ▪ Mechanical Assist Devices ▪ Intra aortic balloon pump (IABP) ▪ Impella ▪ Ventricular Assist Device (VAD) ▪ Heart transplant ▪ ECMO Cardiac Resynchronization Therapy (CRT) ▪ Special type of PM that helps to treat HF ▪ Paces both ventricles, which helps to coordinate the myocardial contraction → stronger contraction/increase CO ▪ May help to improve symptoms (i.e. SOB) and decrease mortality ▪ Not all patients achieve the expected benefits Intra Aortic Balloon Pump (IABP) Inserted via a large artery into the descending aorta Lowers afterload Increases coronary blood flow If inserted into femoral artery - No hip flex >30 degrees in supine Maybe able to walk if inserted into axillary or subclavian artery; no shoulder flex > 90 Monitor vital signs and insertion site of IABP during mobility Impella Device Mini ventricular assist device that provides short term support of the left ventricle Continuously draws blood from the left ventricle then expels it into the ascending aorta ↓ LV work and myocardial demand ↑ MAP, CO, systematic perfusion and coronary flow  Mobilization on Impellas Patients are only in the ICU Type of impella dictates if the patient can be mobilized Limited evidence in the literature about mobilizing patients on Impellas Monitor vital signs pre and post mobility  Left Ventricular Assist Device (LVAD) Used for end stage HF that is unresponsive to medical intervention Performed via sternotomy or thoracotomy Continuous flow LVAD No pulses – unable to palpate HR or obtain manual BP readings Often low functioning but able to show improvement with rehab/exercise training  Indications ▪ Individuals with HFrEF (NYHA Class IV) Left Ventricular ▪ Bridge-to-transplant Assist ▪ Destination therapy Device ▪ Bridge-to-Recovery Functional Status post LVAD Exercise capacity remains low after LVAD placement Pre 3-6 months 1 year > 1 year (Leibner et al. ASAIO 2013)  Borg RPE 11-13 (6-20 scale) Dyspnea 3L/min ECG changes (ST shifts no > 1mm and/or increasing ventricular arrhythmias) (Scheiderer, 2013) Decreased SpO2 (if available) Watch for symptoms of exercise intolerance  Left Ventricular Assist Device (LVAD) Acute Care Setting Management of acute care factors Wound/skin integrity (driveline and use of abdominal binder) Pulmonary hygiene Progressive mobilization Monitor flow rate, MAP, HR, RPE Watch for signs of exercise intolerance Education How to hook/unhook LVAD to/from batteries Left Ventricular Assist Device (LVAD) Outpatient Setting Cardiac rehab (if available) or exercise training Goal 20-60 minutes RPE 11-13 Strength training after 4-8 weeks Heart Transplantation ▪ Surgery that replaces the diseased heart with a healthy heart ▪ Used for management of end stage heart failure ▪ Survival rate 85-90% ▪ Performed via sternotomy ▪ Results in a deinnervated heart Post-Transplantation Heart is denervated Loss of autonomic nervous system modulation Increase adrenal release of norepinephrine Resting HR 95-115 bpm Response to exercise is delayed and blunted Lower peak HR No angina (usually)  Heart Rate Response in the Transplanted Heart (Braith, 2000)  Post-Transplantation (Acute) Address any pulmonary issues Gradual progress patient’s mobility/activity tolerance Supine →Sitting →Standing → Walking **Need a warm-up and cool down Monitor HR but also watch BP, RPE and symptoms of fatigue Provide education Sternal precautions Denervated heart rate response HEP  Rejection Scale GRADE FINDINGS 0 No rejection 1 Mild rejection 1A Focal infiltrate without necrosis 1B Diffuse, sparse infiltrate, no necrosis 2 Moderate rejection, 1 focus, aggressive infiltrate and/or myocyte damage 3 Moderate rejection 3A Multi-focal, aggressive infiltrates and/ or myocyte damage 3B Diffuse inflammatory process with necrosis 4 Severe rejection  Exercise Capacity After Transplant (Williams, 2012) Out-Patient Cardiac Rehab Aerobic training Strength training Address any musculoskeletal problems Education/HEP/Self Monitoring  Aerobic Training ▪ Frequency – Minimum 3 days/week, prefer 5 days/wk ▪ Intensity – Use RPE only (11-14) or talk test ▪ Time – Progressively increase to 20-60 min/day ▪ Type – Aerobic exercise: walking, treadmill or cycle Heart Transplant Strength Training FITT ▪ Frequency – 1-2 days/week (nonconsecutive) (ACSM, 11th Ed) ▪ Intensity – Begin at 40% 1-RM and progress to 70% ▪ Time – 1-2 sets of 10-15 reps of major muscle groups ▪ Type – Weight machines, elastic bands, and/or body weight  ▪ Need a prolonged warm-up and cool-down Tips for ▪ Initial intensity may be at 40-50% Exercising a ▪ Monitor vital signs and watch for Patient after inappropriate responses Heart ▪ No exercise when rejection Transplantation reaches a level 3 ▪ Sternal precautions for 4-6 weeks ▪ Alternate between UE and LE exercise Heart Transplant Patient Completed 3 marathons, 4 half Ironman and 5 full Ironman competitions Normal/Above normal exercise capacity Extracorporeal Membrane Oxygenation (ECMO) ▪ Used to support patients with severe cardio- pulmonary dysfunction that is unresponsive to conventional treatment ▪ Cardiogenic shock ▪ Bridge to heart tx ▪ Cardiac arrest ▪ ARDS ▪ Bridge to lung tx ▪ COVID ▪ Due to the medical complexity of these patients, many are on prolonged bedrest ▪ Experience significant weakness and lower levels of mobility  Mobility on ECMO Determine Gather Progress Determine medical Gather team (RN, Slowly progress stability and obtain perfusionist, RT (if mobility as order needed), additional tolerated help to secure lines) Monitor vital signs and flows Monitor cannulas https://www.cpr.org/show-episode/june-22-2021-learning-to-breathe-again-colorados-1st-covid-19-lung-transplant-recipient / Tonna, Ann Am Thor Soc 2022 Implantable Cardiac Devices Pacemakers (PM) ▪ Produce an artificial action potential for controlling certain cardiac arrhythmias ▪ Indications ▪ Bradycardia ▪ Heart blocks ▪ Tachycardia ▪ May be combined with AICD ▪ PM programming mode can influence a patient’s exercise capacity ▪ Fixed rate ▪ Demand/inhibited mode ▪ Synchronized mode Permanent Pacemaker (PPM) ▪ Consists of implantable pulse generator and lead wires that connect to the myocardium ▪ Endocardial leads attached to the right atrium/ventricles with the generator placed below the clavicle ▪ PM Precautions (no shoulder flex/abd > 90; no extension; no lifting/pushing/pulling) x 4-6 weeks ▪ Groin precautions x 1 week if used to place the PM Leadless Pacemaker ▪ Newer device where all of the components of the PM are inside one device ▪ Placed in the right ventricle ▪ Doesn’t need leads or generator (no chest incision) ▪ Only able to pace one ventricle and unable to defibrillate ▪ No postop precautions Pacemaker Malfunction Can occur if there are cracks in the leads or if the equipment is not working properly Symptoms: ▪ Dizziness ▪ Syncope ▪ Shortness of breath ▪ Confusion ▪ Chest pain ▪ Cardiac arrest  Detects and corrects life-threatening arrhythmias by delivering an electrical shock Automatic Implantable Same post op precautions as a PM Cardioverter Defibrillator (ICD or AICD) Important to know at what rate the device will fire and keep the HR 10- 15 beats below this rate Wearable Cardioverter Defibrillator (Life Vest) ▪ Able to detect and defibrillate VT/VF ▪ Often used when AICD implantation has to be deferred (i.e. active infection)