12.11.21 Cardiac

Heart failure basics

• • Definition

    • Inability of the heart to provide oxygen requirements of tissue

    • Or only at the expense of raised LV filling pressure

  • Causes

    • 50% CAD

    • Idiopathic 25%

    • Valve disease 10%

    • HTN 4%

    • Alcohol 4%

  • Survival varies depending on aetiology

    • But pooled 5-year survival is <50%

  • Signs

    • Raised JVP

    • Hepatojugular reflex

    • 3rd heart sound

    • Displaced apical impulse

    • Murmur

  • CXR

    • A - Alveolar oedema

    • B - B lines

    • C - Cardiomegaly

    • D - Diversion to upper lobe

    • E - Effusion

  • BNP

    • False positive if old, female, AF, LVH, renal or resp failure, PE ...

  • Drugs with survival benefit

    • ACE inhibitor

    • Beta blocker

    • Spironolactone

  • Calcium channel blockers in heart failure

    • NOT diltiazem or verapamil as they decrease contractility

    • Dihydropyridines (e.g. nifedipine) are OK as they have peripheral action

  • Pacing

    • Can help heart failure

    • DON'T put pacing leads, or anything else, in the left heart!

      • cf thrombosis

    • If you need LV pacing, thread it round the veins, on the outside

Angina

• • Definition

    • Chest pain described as constriction/discomfort in chest, +/- radiation

    • Brought on by exercise or emotion

    • Relieved by rest or GTN

  • Not all 3?

    • Only 2 out of 3 = Atypical angina pain

    • 0 or 1 out of 3 = Non-anginal pain

  • Most common cause

    • Atherosclerotic narrowing of coronary arteries

    • Symptomatic if >70%

  • Risk factors

    • Fixed

      • Age

      • Male

      • Genetics

    • Modifiable

      • Tobacco

      • HTN

      • DM

      • Hypercholesterolaemia

      • Depression

      • Obesity

  • Treatment options

    • Lifestyle modification

    • Pharmacotherapy

    • PCI

    • Surgical revascularisation

  • ECG features

    • T wave inversion

    • ST depression

    • LVH

    • LBBB

  • Exercise stress test

    • Very poor specificity

    • Therefore only useful when PPV is high

      • i.e. Previous Hx of CVD

  • Investigation based on risk

    • <10% => Consider non-cardiac cause

    • 10-30% => Do CT calcium score

    • 30-60% => Do functional test

      • Myoperfusion scan

      • Dobutamine stress echo

      • Stress MRI

    • 60-90% => Straight to coronary angiogram

  • CT calcium score interpretation

    • 0 => Consider other causes

    • 1-400 => 64-slice CT coronary angiography

    • >400 => Invasive angiography as you won't see shit on a CT angiogram

  • Treatment

    • Symptoms

      • Start with a beta blocker

      • Add a CCB if still symptomatic

        • Use a non-dihydropyridine (diltiazem, verapamil)

          • Block the AV node and slow rate

      • Then add ranolazine if still symptomatic

        • Sodium channel blocker

      • Plus PRN GTN

    • Secondary prevention

      • B - Beta blocker

      • A - Aspirin

      • S - Statin

      • I - ACEi

      • C - Control risk factors

  • Checkups

    • Glucose

    • Lipids

    • Hb

    • TFTs

    • U+Es

  • Indications for surgery over PCI

    • Disabled

    • > 65

    • Complex 3-vessel disease

    • Left main stem disease

ACS

• • Subtypes

    • STEMI

    • NSTEMI

    • Unstable angina

  • The 11 Ps

    • Pain relief

      • Morphine + cyclizine

    • Paralyse the platelets

      • Aspirin, clopidogrel, LMWH

    • Pacify the plaque

      • High-dose statin

    • Perfuse the myocardium

      • PCI

    • Prevent adverse remodelling

      • ACEi, Beta blocker

    • Predict risk of sudden death

      • GRACE, Echo

    • Protect from sudden death

      • Aldosterone receptor antagonist (eplerenone)

        • NB less anti-androgen effects than spironolactone

    • Promote exercise

    • Prevent smoking

    • Praise health

    • Permit sex after 2 weeks

  • Other things causing a trop rise

    • Myocarditis

    • Tachyarrhythmia

    • DC cardioversion

    • Sepsis

    • Trauma

    • CPR

    • Renal failure

    • Cardiomyopathy

    • PE

Arrhythmias

• • Types and causes

    • Brady

      • Sinoatrial node disease

      • Conduction disease

    • Tachy

      • AF/flutter

      • SVT

        • AVNRT

        • AVRT

        • Atrial tachyarrhythmia

      • VT

      • VF

  • Sinus node disease - subtypes

    • Slow rate

    • Occasional failure

    • Exit failure

    • Tachy-Brady syndrome

  • LBBB

    • Supraventricular origin

    • QRS ≥ 120 ms

    • QS or rS complex in V1

    • RsR' wave in V6

  • Wenkiebach

    • Progressively longer PR, then dropped beat

  • Mobitz II

    • Regular dropped beats

  • Escape

    • Infranodal

      • Broad QRS, as not using normal pathway

    • High junctional

      • Uses His-Purkinje system => Narrow QRS

  • Junctional bradycardia

    • Retrograde P waves

    • Weird STs

    • May see in a paced rhythm

  • AF

    • May be coarse or fine

    • Often originates in areas round the pulmonary vein

    • Bigger heart => Predisposition to AF

      • And AF => Bigger heart, so AF BEGETS AF

  • Atrial flutter

    • Dependent on a SLOW ZONE for re-entry round the circuit

      • So can fix by ablation of this zone

    • Conduction through the AV node may be regular or variable

  • Atrial tachycardia

    • Due to enhanced automaticity

    • With AV block, can look like flutter

  • AVNRT

    • Suspect AVNRT if there's an unexplained tachycardia

    • Dependent on the slow and fast pathways through the AV node

      • Can set up a self-propagating loop

      • This then spreads out to the ventricles and sometimes to the atria too

        • => Retrograde P waves

    • P waves may be buried in other stuff, making it all look weird

  • AVRT

    • Orthodromic

    • Normal pathway carries impulse to ventricles

      • Uses bundle of His => Narrow QRS complexes

    • Impulse retrogradely re-enters the atrium via the accessory pathway

      • P waves follow QRS complexes

    • Antidromic

    • Accessory pathway carries impulse down into ventricles

      • • Outside of the bundle of His => Wide QRS, maybe with delta wave

    • Impulse re-enters the atrium retrogradely via the AV node

    • Pathway: Posterioseptal or right-sided

  • Pre-excitation

    • WPW

    • Delta waves

  • VT

    • Types

      • Polymorphic

      • Monomorphic

    • Check the axis to see if it could be coming from the AV node

    • Broad-complex tachycardia is VT until proven otherwise

Notes

• • ACS stats

    • 40% of A&E admission are for chest pain

    • 40% of STEMIs die within minutes

  • LBBB causes

    • Underlying CVD

    • Underlying heart muscle disorder

    • Congenital conduction disorder

    • Calcific aortic stenosis

  • Key drugs for management of angina: BETA BLOCKER AND CALCIUM CHANNEL BLOCKER

  • Normal sinus rhythm vs Atrial premature depolarisations vs SVT

  • Epsilon wave

    • Small positive deflection (‘blip’) buried in the end of the QRS complex

    • Characteristic finding in arrhythmogenic right ventricular dysplasia (ARVD)