Heart Failure- inability of CO --> physiologic demands


Atrial Fibrillation- chaotic, irregular atrial rhythm at 300-600bpm
uncoordinated atrial activity on surface ECG - temporal, paroxysmal, persistent, permanent

Epi

  • age - 2in 1000 UK - 23 mill worldwide

Signs/Symptoms

Left

  • SOB (orthopnea) - when supine (increased venous return from redistribution of blood - gravity effect - exacerabates pulmonary vascular congestion)
  • paroxysmal nocturnal dyspnea - breathless awakening from sleep - increased venous return from redistibution of blood, reabsorption of peripheral edema
  • cough
  • confusion
  • decreased urine output
  • nocturia
  • pulmonary edema- incresed pulmonary venous pressure --> pulmonary venous distention and transudation of fluid- presence of hemosiderin-laden macrophages (HF cells in lungs)
    Signs:
  • pul. crackles
  • accenuated P2
  • mitral regurgitaiton murmur
  • pulse alterations

Right

  • peripheral edema/sacral/ascites
  • hepatosplenomegaly - increased central venous pressure --> increased resistance to portal flow
  • anorexia
    Signs:
  • increased JVP/Kausmal signs (increased JVP with insipration)
  • tricuspid regurgitation
  • palpable right ventricle

Aetiology/Pathophysiology

Causes:
IHD, cardiomyopahty, hypertension, valvular HD- mitral/aortic/tricuspid

  • congenital HD
  • alcohol/drugs
  • hyperdynamic circulation
  • tricuspid incompetence
  • arrhythmias
  • pericardial disease

Systolic - inadequate myocardial contractile function - consequence of IHD/hypertension


Diastolic dysfunction - inability of heart to adequately relax and fill - massive left ventricular hypertrophy, myocardial fibrosis, amyloid deposition, contrictive pericarditis

Pathophysiology - compensate for reduced myocardial contractility:


Frank-Starling

  • increased EDV filling --> stretch cardiac myofiber --> increasing CO --> compensation
    • ventricular dilation - expense of increased wall tension --> amplifies o2 requirements --> decompensation

Activation of neurohumoral systems:

  • NE by ANS --> increase HR + contractility + vascular resistance
  • activation of RAAS --> water and salt retention --> increases vascular tone
  • release of ANP - acts to balance RAAS through diuresis ans vascular SM relaxation

Myocardial structural changes:

  • cardiac myocytes cannot proliferate --> adapt to increased work by increasing no. of sarcomeres (hypertrophy)
    • pressure overload states - hypertension or valvular stenosis - new sarcomeres added parallel to myocytes (concentric hypertrophy)
    • volume overload states - valvular regurgitation or shunts - new sarcomeres added in series with existing --> muscle fiber lenght increases - ventricle dilate - wall thickness - increased, normal or decreased

Diagnosis

  • serum BNP (100-400) or N-terminal pro-BNP (<300)

if BNP >400 - refer immediately

  • transthoracic doppler echo
  • ECG/CXR/blood - electrolytes/U&E/eGFR
  • TFT/LFT/fasting lipid/FBC

Management

Acute

  • diuretics
  • morphine
  • Nitrate (people with concomitant MI, severe HTN, regurgitant aortic or mitral valve disease)
  • oxygen

Chronic

  • lifestyle - exercise, smoking, alcohol, sexual activity, vaccination (influenza, pneumococcal disease), air travel, driving


  • ACEi + beta blockers

  • aldosterone antagonist
  • ARB
  • hydralazine + nitrate (African/Caribbean descent)
  • Digoxin - worsening or severe HF

All types:

  • diurectics (congestive symptoms and fluid retention)
  • CCB - amlodipine - comorbid HTN (avoid verapamil/dilitiazem or short acting dihydropyridine)
  • amiodarone
  • Anticoagulants - thromboembolism, LV aneurysm, intracardiac thrombus
  • Aspirin - HF + artherosclerosis (CAD)
  • inotropic agents - dobutamin, milrione, enoximone - short term treatment of acute decompensation of CHF

Epi/Risk factors

0.5-1% , increasing age,
HTN, CAD, CHF, age, DM
rheumatic valvular --> mitral stenosis
alcohol --> cardiomyopathy
arrhythmias --> reentrance
smoking
thyroid

Aetiology

HF, HTN, valve disease - mitral stenosis, regurg, hyperthyroidism, alcohol induced, familial, electrolytes

Signs/Symptoms

incidental/none, chest pain, palpitations, dyspnea, faintness, stroke/TIA, syncope/dizzyness


Signs- irregularly irregular pulse, apical pulse rate > radial, 1st HS- variable

Pathogenesis- pul veins --> dysfunction of cardiac electrical signalling, atria no longer in contract in coordinated manner, atria fall to empty adequately (no longer coordinated contraction)

Diagnosis

  • ECG- P waves - absent, irregular QRS complex (RR intervals), narrow QRS


  • Blood - U/E - cardiac enzymes, thyroid function, echo --> atrial enlargement/ mitral valve disease



Management

Thromboprophylaxis
Assessment of stroke: CHA2DS2VASc - age, sex, CHF, HTN, stroke hx, vascular disease hx, DM hx


Assessment for major bleeding risk - HAS BLED - HTN, Renal disease , Liver disease, stroke, prior major bleeding or predisposition to bleeding, age >65, medication (antiPLT/NSAIDs), alcohol or drug use > 8 drinks


  • Anticoagulation (men with score >1, people >1)


    • apixaban, dabigatran etexilate, rivaroxaban or Vit K antagonist
    • Apixaban (AF + 1 risk factor - stroke/TIA, >75, HTN, DM, HF)



      • Dabigatran etexilase - non valvular AF + 1 RF (previous stroke, TIA/embolism, LVEF <40%, class II HF, >75, >65 + DM, CAD, HTN)
    • Rivaroxaban - AF + 1 RF (CHF, HTN, >75, DM)


  • Vit K antagonists - calcular TTR



Rate and Rhythm Control
Rate (give as 1st line except when reversible, HF caused by AF, new onset AF, atrial flutter)

  • Beta blocker (except sotalol) or Rate limiting CCB
  • Digoxin - monotherapy with non paroxysmal AF + sedentary


  • Combination therapy (2 of)


    • beta blocker
    • diltiazem
    • digoxin

Rhythm - pharm/electrical- AF whose symptoms continue after HR controlled or rate control not successful

  • Cardioversion
    • AF > 48h
    • amiodarone - starting 4 weeks before and continuing upto 12 months after electrical cardioversion to maintain sinus rhythm
    • Transosophageal echocardiography (TOE) and conventional cardioversion
      -
  • Long term


    • beta blockers
  • Drondedarone (sinus rhythm after cardioversion in paroxysmal or persistent AF)