cardiac failure and associated notes.pptx

Notes

1. CONGESTIVE CARDIAC FAILURE Dr.okuku

2. Outline Introduction Pathophysiology Aetiology Clinical presentation Management Cardiac Failure in Children

3. Important definitions Cardiac output = stroke volume X heart rate. Stroke volume = amount of blood ejected from the ventricle in each cardiac cycle. Preload = tension on the muscle as it begins to contract. Quantity of blood in the ventricle at systole. Afterload =resistance against which the heart has to pump. Will determine the end-systolic volume. Cardiac Failure in Children

4. Introduction Syndrome of ventricular dysfunction xterized by inadequate cardiac output to meet the metabolic demands of the body Left ventriculr failure causes shortness of breath and fatigue whereas right ventricular failure causes peripheral and abdominalfluid accumulation However both are involved to some extent Because of an inherited or acquired abnormality of cardiac structure and/or function, Patient develops a constellation of clinical symptoms (dyspnea and fatigue) and signs (edema and rales) Cardiac Failure in Children

5. epidemiology more than 20 million people affected. prevalence of 2% in adult population in developed countries prevalence follows an exponential pattern, rising with age, and affects 6–10% of people over age 65 relative incidence is lower in women, but half of the cases seen are female patients The overall prevalence of HF is thought to be increasing, in part because current therapies for cardiac disorders HF patients are now broadly categorized into one of two groups: Cardiac Failure in Children

6. Etiology Any condition that leads to an alteration in LV structure or function can predispose a patient to developing HF Coronary artery disease (CAD) -60-75%, HTN in 75% of the cases incuding CAD The exact etiologic basis is unknown in 20-30% of cass These patients are referred to as having nonischemic, dilated, or idiopathic cardiomyopathy if the cause is unknown Rheumatic heart disease remains a major cause of HF in Africa and Asia, especially in the young. Cardiac Failure in Children

7. Cardiac Failure in Children

8. Prognosis Symptomatic HF still carries a poor prognosis despite advances in mgt 30–40% of patients die within 1 year of diagnosis, 60–70% die within 5 years, Worsening HF or as a sudden event (probably because of a ventricular arrhythmia) are responsible for most of the deaths Patients with symptoms at rest ( [NYHA] class IV) have a 30–70% annual mortality rate, whereas patients with symptoms with moderate activity (NYHA class II) have an annual mortality rate of 5–10%. Therefore unctional status is an important predictor of patient outcome Cardiac Failure in Children

9. Cardiac Failure in Children

10. Pathogenesis HF may be viewed as a progressive disorder that is initiated after an index event either damages the heart muscle, with a resultant loss of functioning cardiac myocytes, or, alternatively, disrupts the ability of the myocardium to generate force, Thereby preventing the heart from contracting normally. Index event may have an abrupt onset e.g. an MI; or gradual or insidious onset , as in hemodynamic pressure or volume overloading; or hereditary, as in genetic cardiomyopathies May go asymptomaticor minimally symptomaticfor a while due to compensatory mechanisms (RAAS, adrenergic system and increasedcontractility) Cardiac Failure in Children

11. Cardiac Failure in Children

12. Pathophysiology Reduced cardiac output leads to tissue hypoxia Hypoxia results into local vaso -dilatation and reduced blood pressure This activates the sympathetic nervous system and the renin-aldosterone - angiotensin system (RAAS) Cardiac Failure in Children

13. Pathophysiology These result into: Increased HR Enhanced myocardial contractility Vaso -constriction Sodium and water retention Initially this improves cardiac output and maintains BP for some time If sustained, there’s more demand on cardiac muscle and myocardial oxygen needs Cardiac Failure in Children

14. Pathophysiology This leads to cardiac remodeling to meet the demands: Expansion of myocytes Resultant myocardial hypertrophy with no accompanying capillary formation Leads to myocardial ischemia and worsens cardiac output. There’s congestion of the heart with blood Less functional heart, leading to chronic form and death Cardiac Failure in Children

15. Clinical manifestations Cardinal symptoms of HF are fatigue and shortness of breath Orthopnea PND Chyne stokes breathing (diminished sensitivity of the respiratory center to arterial Pco2) Other symptoms include Anorexia, nausea, and early satiety associated with abdominal pain and fullness are common (edema of the bowel wall and/or a congested liver) Cerebral symptoms such as confusion, disorientation, and sleep and mood disturbances (cerebral hypoperfusion) Cardiac Failure in Children

16. Clinical manifestations Neonates and infants Poor activity Dyspnea Feeding difficulties (short breastfeeding times) Poor somatic growth Profuse perspiration Recurrent pulmonary infections Cardiac Failure in Children

17. Physical exam findings General appearance: distress, cyanosis, cold extremities, elevated or low BPs, increased JVP (>8cm) pulmonary exam: rales or crepitations, wheezing, pleural effusions cardiac exam: murmurs, displacement of PMI, abdomen: RUQ tenderness, hepatomegaly, ascitis, jaundice extrmities: edema Cardiac Failure in Children

18. Signs Tachypnea , dyspnea and grunting Tachycardia Gallop, murmur Hepatomegaly , oedeema Cardiac Failure in Children

19. Older children Exercise intolerance Samnolence Anorexia Cough, wheeze, crackles Plus the signs of infants Cardiac Failure in Children

20. routine work up Complete blood count, a panel of electrolytes, blood urea nitrogen, serum creatinine, hepatic enzymes, and a urinalysis. Selected patients should have assessment for diabetes mellitus (fasting serum glucose or oral glucose tolerance test), dyslipidemia (fasting lipid panel), and thyroid abnormalities (thyroid-stimulating hormone level) Cardiac Failure in Children

21. Work up Pulse oximetry to detect oxygen saturation ECG - cardiac rhythm and determine the presence of LV hypertrophy or a prior MI (presence or absence of Q waves) as well as to determine QRS width to ascertain whether the patient may benefit from resynchronization therap Chest radiography: hypertrophy, pulmonary oedeema , pleural effusion Echo- cause. Cardiac markers: BNP, ANP, troponin T and I, C-reactive protein, TNF receptors, and uric acid Cardiac Failure in Children

22. Management General measures: Bed rest, limit activities and interferance Sitting up, cardiac bed Control fever, infections (pneumonia, sepsis) Tube feeding in small infants Correct acidosis, anemia, hypoglycemia, hypocalcemia Give supplemental oxygen Cardiac Failure in Children

23. Cardiac Failure in Children

24. Management Treat specific cause, eg anaemia , sepsis, arrthymias , fliud overload Surgical correction of malformations Medical mgt Aims at maximizing cardiac output while minimizing myocardial stress and oxygen needs Aims at reducing preload and afterload Cardiac Failure in Children

25. Cardiac failure pharmatherapy Duiretics Increase water and sodium loss Reduce preload R educe systemic and pulmonary oedeema First step in treatment Mainly loop diuretics, but also thiazides and metolazone Cardiac Failure in Children

26. Digoxin Inotropic effects Slows heart rate reducing cardaic muscle oxygen demands Inhibits sympathetic nervous system Inhibits renin release Cardiac Failure in Children

27. ACEI Reduce vaso -constriction, leading to reduction in afterload Dumpens sympathetic activity and aldosterone release, hence reduction in preload too. Captopril , enalapril , etc Angiotensin receptor blockers As ACEI, but not superior Little evidence Lorsatan Cardiac Failure in Children

28. Aldosterone antagonists Spiranolactone Reduce effects of RAAS, hence reduced sodium and water retension Reduced myocardial fibrosis (useful for long term use) Cardiac Failure in Children

29. Beta-blockers Block sympathetic nervous system Slows heart rate ( decresing it’s oxygen demands and allowing it diastolic filling) Reduces myocardial apoptosis and fibrosis Anti- arrthymic effects Synergism with ACEI Cardiac Failure in Children

30. Summary Pharmacotherapy of heart failure Severe acute cases: loop diuretic, ACEI, spiranolactone +/- digoxin ( depending on the cause and underlying disease condition ) Combining 3-4 drugs Mild acute cases : diuretics + ACEI or Digoxin Stable cases Loop diuretics, spironolactone , B-blockers or digoxin . Cardiac Failure in Children

31. References Harrison’s Cardiovascular Medicine 2nd edition-Joseph Loscalzo Merck Manual of medicine Uptodate 26.1 Cardiac Failure in Children

32. “Live as if you were to die tomorrow. Learn as if you were to live forever”. (Mahatma Gandhi) End Cardiac Failure in Children