Cardiac Overview Flashcards
What is Heart Failure?
Heart failure is a progressive clinical syndrome caused by a structural or functional abnormalities of the heart, resulting in reduced cardiac output. In essence the heart can’t keep up with demands
How does the heart adapt to reduced cardiac output
- Enlarging: the heart stretches to contract more strongly and keep up with the body’s demand to pump more blood. Over time, this causes the heart to enlarge
- Developing more muscle mass: the increase in muscle mass occurs because the contracting cells of the heart get bigger. This lets the heart pump more strongly, at least initially
Pumping faster: this helps increase the hearts output
- Developing more muscle mass: the increase in muscle mass occurs because the contracting cells of the heart get bigger. This lets the heart pump more strongly, at least initially
Other ways the heart compensates for reduced cardiac output in heart failure
- The blood vessels narrow to keep blood pressure up, trying to make up for the heart’s loss of power
The kidney’s retain more salt and water rather than excrete it through urine. This creates increased volume of blood, which helps maintain blood pressure and allows the heart to pump stronger. But overtime this extra volume can overtask the heart, making heart failure worse.
Common causes of heart failure
- Ischaemic heart disease
- Arrhythmias
- Hypertension
- Valve disease
- Sepsis
- Stress
- Alcohol/substance misuse
- Myocarditis/pericarditis
- Cardiomyopathies
- Dilated
- Hypertrophic
- Congenital
Symptoms of decompensated heart failure
- Breathlessness (often on minimal exertion)
- Struggle getting themselves ready in the morning
- Unable to talk in full sentences
- Orthopnoea/PND
- Often sleep in a chair
- Palpitations
- Tiredness
- Low Mood
- Cardiac Wheeze
- Increasing weight
- Dizziness/lightheaded
- Body oedema
Acute heart failure treatment
- Acute Heart Failure treatment:
- Loop diuretics
- Oral Vs IV
- Bolus Vs Infusion
- Weighing the patient daily
- Monitoring biochemistry
- Thiazide like diuretic for resistant oedema
- Bendroflumethiazide or metolazone
Powerful synergistic effect!
- Bendroflumethiazide or metolazone
Treatment of heart failure
ACEi/ARB
Beta blockers
Mineralocorticoid Receptor Antagonist
Sacubitril/Valsartan
SGLT2i
Other medications in heart failure
- Digoxin:
- DIG study – reduction in hospitalisations. No reduction in mortality
- Low dose : 62.5-125mcg. AF or sinus rhythm. Positive inotrope. Not often used (for HF Tx)
- Monitor K+ and renal function
- Nitrate + Hydralazine:
- Trials: V-HeFT + A-HeFT
- Used in those patients who cannot tolerate ACEi/ARB/ARNI
- Benefit mainly seen in black patients. Not often used * Ivabradine:
- Trial: SHIFT – reduced hospital admissions mainly * Only Sinus rhythm. Used if HR not controlled on beta blocker. HR >75BPM to initiate
- Negative outcomes in patients with low HR
- Monitor QTc, lots of interactions!
- IV Iron
- Trial: FAIR-HF / AFFIRM-AHF (ferinject) / Ironman (ferric derisomaltose)
- Symptomatic benefit / some reduction in hospitalisation
What is an arrythmia
- An arrhythmia is an abnormal heart rhythm. Your heart is controlled by a conduction system which sends out electrical impulses. This causes a heartbeat.
- Arrhythmias are caused by a problem in this conduction system, which can make your heart beat too slowly, too quickly, or in an irregular way.
Main types of arrythmias
- Atrial Fibrillation
- Atrial flutter
- Heart block (1st degree, 2nd degree, 3rd degree – CHB)
- Ventricular Tachycardia
- Ventricular Fibrillation
Main causes of arrythmias
- Older age
- Blocked heart arteries
- Previous heart attack
- Smoking
- Illicit drug use
- High blood pressure
- Structural heart disease – cardiomyopathy
- Heart abnormality at birth
- Previous heart surgery
- Having previous arrhythmias
- Stress
- Medications
Medications that cause arrythmias
- Ivabradine / ranolazine
- Amiodarone / Dronedarone
- Flecainide
- Antidepressants
- Antipsychotics
- Antibiotics / Antifungals
- Cancer treatments
Medications used to treat arrythmias with a FAST ventricular rate
Main medications seen in practice
* Beta blockers – most commonly used
* Rate limiting calcium channel blockers – not in patients with HFrEF (negative inotrope)
* Digoxin – narrow therapeutic index
* Amiodarone
* Flecainide
Amiodarone
➢ Powerful anti-arrhythmic medication
➢ Oral Loading regime: 200mg TDS 7/7, 200mg BD 7/7, 200mg OD maintenance. ~50 days half life
➢ Biochemistry to check: LFTs, TFTs – baseline and every 6 months
Amiodarone counselling
Yearly eye test, wear at least SPF 30 sun cream
Risk of stratifying likelihood of stroke and major bleeding
- Offer anticoagulation to people with a CHA2DS2 -VASc score of 2 or above, taking bleeding risk into account.
- Consider anticoagulation for men with a CHA2DS2 -VASc score of 1, taking the bleeding risk into account.
- Do not offer an anticoagulant to women with a CHA2DS2 -VASc ≤ 1 or men with a CHA2DS2 -VASc score of zero; Review these patients at age 65 or if develop diabetes or cardiovascular comorbidities
- The ORBIT score should be used to help make an informed decision about the risk of bleeding and should not be used to exclude patients from oral anticoagulation
DOAC monitoring
Check FBC , U+Es, LFTs
* Annual minimum
* Crcl 30-60ml/min; >75ys or fragile: 6 monthly U&Es
* Crcl 15-30ml/min 3 monthly U&Es. Perform additional tests if other illness that may have impact
* Or if Crcl <60ml/min divide by 10 to give frequency of monitoring in months
ACS
‘Acute coronary syndromes’ - a spectrum of conditions that share a common causation and includes:
* Unstable Angina
* Non-ST elevation myocardial infarction (NSTEMI)
* ST- elevation myocardial infarction (STEMI)
Unstable angina
- Arteries are partially blocked
- Cardiac function is compromised and patient is at risk of MI
Patient experience severe, unpredictable chest pain not associated with exertion
- Cardiac function is compromised and patient is at risk of MI
NSTEMI
- Arteries are substantially blocked
Platelet aggregates may cause embolization of smaller arteries downstream
STEMI
- Arteries are completely blocked
Heart muscle is extensively damaged putting the patient at risk of a fatal heart attack
Modifiable risk factors ACS
- Smoking
- High blood cholesterol
- High blood pressure
- Physical inactivity
- Obesity
- Diabetes Mellitus
Non modifiable risk factors ACS
- Increased age
- Male sex
- Family history
- Race
ACS symptoms
- Chest Pain – crushing, dull
- Pain that originates in the centre of the chest & radiates to the arms, neck or jaw
- Sweating
- Shortness of breath
- Nausea
- Some patients have no symptoms
