CV conditions Flashcards
define cardiac failure: diastolic vs systolic
heart can’t meet O2 demands
diastolic - impaired filling
systolic - impaired pumping
What are the main causes of heart failure?
Ischaemic heart disease Hypertension Cardiomyopathy Valve defects - aortic stenosis Arrhythmias Congenital defects
Describe how long term hypertension may lead to heart failure
long term hypertension leads to hypertrophy of myocardium in order to pump harder to overcome the increased arterial pressure in systemic circulation. These larger cells have greater metabolic demands for O2 and so contraction weakens (systolic L HF) *and there is less room for filling (diastolic)
Who is at risk of cardiac failure?
African descent Obese Previous MI Hypertension age 65+ Male
How may an individual with heart failure present?
SOB Fatigue Ankle swelling Dyspnoea Ascites Jugular venous distension Cyanosis
- depending on how far along and whether biventricular
What blood test is used in an individual with suspected heart failure?
If levels were elevated, what other test may you use?
Brain natriuretic peptide: levels correlate with severity.
If levels are raised and ECG is also abnormal, use echocardiography to confirm
Treatments for cardiac failure
- Lifestyle modification
- Meds:
Ace-i eg ramipril or ARB eg candesartan
Beta blocker eg bisoprolol
Digoxin/Inotropes
Diuretics for symptomatic treatment of congestion - furosemide
Aldosterone receptor antagonists eg spironolactone - Revascularisation, surgery eg if cause is valvular, heart transplant in some cases
Peripheral vascular disease cause risk presentation diagnosis treat
Organic (due to a blockage):
atherosclerosis, embolus
Functional (due to constriction)
vasospasm
Risk:
men, obese, smoking, hypertension, diabetes, hyperlipidaemia, age
Presents with intermittent claudication (cramping pain when exercising), elevation pallor/dependent rubor, ulcers that don’t heal normally. If progresses, individual develops critical limb ischaemia: rest pain typically nocturnal, relieved when foot lowered off bed, gangrene - tissue necrosis.
Diagnose
absent/whooshing femoral/popliteal/foot pulse, doppeler USS, ankle-brachial pressure index provides measure of severity and risk of critical limb ischaemia
Treat
lifestyle, underlying conditions
p2y12 inhibitor clopidogrel antiplatelet
Revascularisation in some cases by percutaneous transluminal angioplasty
describe the treatment steps for hypertension
- ACE-i such as ramipril (ARB if contraindicated), or Ca channel blocker such as amlodipine if over 55/afro-caribbean
- Ace-i (or ARB) + CCB
- ACE-I (or ARB) + CCB + thiazide-like diuretic such as bendroflumethiazide
- = resistant hypertension
add aldosterone antagonist/k+ sparing such as spironolactone, increase dose of thiazide-like, or add alpha/beta blocker
Atrial Fibrillation - what? Diagnosis Risk factors Symptoms Complications
Signals are disorganised and override the SAN leading to lots of mini contractions. Not all make it to the ventricles.Twitching, absent P wave and irregular QRS complex on ECG.
May be paroxysmal (lasts 48hrs), peristant (lasts 7 days), long standing persistant and permanent.
Common in individuals with other heart conditions - CAD, hypertension, valvular disease, obesity, diabetes, excessive alcohol. Could stress heart leading to tissue heterogeneity.
May be asymptomatic, or SOB, dizzy, palpitations, fatigue, syncope.
Complications: lots of mini contractions means blood stagnates and clots in the atria, from which they may be pumped to the body/brain causing stroke or embolism.
Treatment of AFib?
- Pharmacology: aim to control heartrate and reduce clotting
Amiodarone
Beta blocker (bisoprolol)
Ca channel blocker (amlodipine)
Digoxin
Warfarin/anticoagulant to reduce clotting risk - Cardioversion: controlled shock aims to return normal rhythm
- Catheter ablation: radiological destruction of diseased area to interrupt abnormal circuits
- Pacemaker
What is atrial flutter and how does it differ from AFib?
Atria contract at high, regular rates as opposed to the random contractions of fib.
Reentrant signal loops back and overrides SAN, starting continuous cycle of contraction.
Less common, associated with fib.
Cause of atrial flutter
Idiopathic (30%) • Coronary heart disease • Obesity • Hypertension • Heart failure • COPD • Pericarditis • Acute excess alcohol intoxication
Associated with atrial fibrillation.
What ECG is characteristic of an individual with atrial flutter?
Symptoms of atrial flutter
Treatment
Regular jagged P waves: sawtooth pattern.
Ratio of atrial : ventricular beats clearly visible.
SOB, dizzy, nausea, palpitations, syncope
Anticoagulate with low dose heparin
Cardioversion
Catheter ablation
amiodarone to restore sinus rhythm
bisoprolol to reduce strain on heart from ventricles decompensating
What is atrioventricular reentrant tachycardia? Most common example?
An accessory pathway in the heart allows signals which have passed through bundle of His to reenter atria and cause contraction before SAN has finished refractory period, leading to periods of tachycardia.
Individuals with Wolff Parkinson-White syndrome have an anatomical accessory pathway.
