cardio

• IV adrenaline and CPR are not necessary if not currently in cardiac arrest.
• IV adenosine is used in the management of narrow complex tachycardias such as supraventricular tachycardias
• IV amiodarone is used after a DC shock has been given in unstable patients. It is also given in stable patients in VT.
• Contrast-enhanced CT coronary angiogram is the first line investigation for stable chest pain of suspected coronary artery disease aetiology
• prolonged QT interval - hypokalaemia, hypothermia, and tricyclic antidepressants
• S1Q3T3 pattern and sinus tachycardia are diagnostic of a pulmonary embolism (PE)
• Drug-eluting stents are now the preferred stent type for primary PCI, and used in a left bundle branch block (MI)
• Aortic stenosis management: aortic valve replacement (AVR) if symptomatic, otherwise cut-off is gradient of 40 mmHg
• Sotalol is known to cause long QT syndrome
• Tricyclic antidepressants, selective serotonin uptake inhibitors and haloperidol are psychiatric drugs known to cause QTc prolongation
• myocardial infarction can lead to an acute mitral regurgitation, causing flash pulmonary oedema
• Marfan's syndrome is a connective tissue disorder associated with mitral valve prolapse.
• Rheumatic fever could result in mitral regurgitation
• Adenosine is given as the first-line pharmacological agent when treating atrioventricular nodal re-entry tachycardia (AVNRT). Adenosine has multiple adverse effects including chest pain, impending feeling of doom, bronchospasm, and transient flushing.
• Cardiac tamponade most commonly has a cause, such as cardiac surgery, trauma, or malignancy
• All thiazide-related diuretics commonly result in hyponatraemia, hypokalaemia, hypercalcaemia, and hypocalciuria.
• ACE inhibitors are known to cause hyperkalaemia.
• Spironolactone is a potassium-sparing diuretic, known to cause hyperkalaemia.
• Dextrocardia is a rare cardiac condition where the heart's apex is located on the right side of the body. Lead I looks right to left, and as the heart is now is essence 'flipped' in this plane, the electric waveform is reversed, this leads to inversion of the P wave, QRS complex and T wave. Loss of R wave progression is also seen in dextrocardia.
• The most common finding in pulmonary emboli (PE) is that of a sinus tachycardia. Right axis deviation can occur. Other ECG features of PE include right bundle branch block and if the clot is large a right ventricular strain pattern can be seen - T wave inversion in V1-4.
• Right ventricular hypertrophy is also associated with right axis deviation
• Myocardial infarcts typically affect the ST segment, T waves and the Q waves.
• Wolff-Parkinson-White syndrome is a condition caused by an accessory conducting pathway, allowing electric activity to bypass the atrioventricular node. In an ECG this is demonstrated by a slurred upstroke of the QRS complex - called a delta wave.
• In general, a bisferiens pulse is a sign of problems with the aortic valve, such as aortic stenosis and aortic regurgitation. Hypertrophic obstructive cardiomyopathy (HOCM) is an autosomal dominant disorder associated with a double pulse. While it is often symptomatic it is a differential for sudden death in younger people.
• Pericarditis - A sharp central chest pain which eases on sitting up and leaning forward and is exacerbated when lying flat or inhaling deep breaths. Systemic lupus is associated. On auscultation, rubbing S1 and S2 sounds. ECG findings - saddle shaped ST elevation is a hallmark of pericarditis.

  Other possible causes of ST elevation could be a STEMI and left bundle branch block.
• In atrial pacing, the ECG would show pacing spikes preceding some or all p-waves.
• Pericarditis, or inflammation of the pericardium, may produce changes consistent with pericardial effusion, such as low QRS voltages or electrical alternans (consecutive QRS complexes will alternate in height as the heart swings in a pendulous motion due to the fluid-filled pericardium), or widespread ST changes - characteristically described as 'saddle-shaped ST-elevation' - due to involvement of the epicardium.
• A ventricular-paced strip will show a pacing spike preceding some or all QRS complexes.
• rheumatic fever - presentation of a preceding sore throat, migratory joint pains involving large joints such as knees, hips and ankles, pink ring-shaped lesions on the trunk (erythema marginatum), and jerking movements of the face and hands (Sydenham chorea) are all characteristic features.

  Rheumatic fever is an inflammatory disease that can develop as a complication of inadequately treated group A streptococcal pharyngitis (Streptococcus pyogenes). It affects multiple organ systems including the joints, skin, heart, and nervous system.
• Lyme disease is caused by the bacterium Borrelia burgdorferi, transmitted to humans through the bite of infected black-legged ticks. 
• Infective endocarditis is an infection of the inner lining of the heart chambers or valves (endocardium), usually caused by bacteria entering the bloodstream. Although it may cause joint pain due to immune complex deposition in some cases, it typically presents with other signs such as fever, heart murmur, petechiae or splinter haemorrhages under nails.
• Polyarticular juvenile idiopathic arthritis is a chronic autoimmune condition characterized by inflammation in five or more joints within the first six months after onset.
• Still's disease, also known as systemic-onset juvenile idiopathic arthritis, is another autoimmune condition that can cause joint pain, fever, and rash.
• Shortness of breath, peripheral oedema, and paroxysmal nocturnal dyspnoea (waking up at night short of breath) suggest heart failure. The initial first-line step in managing heart failure is prescribing an ACE inhibitor and beta-blocker. next step would be to add an aldosterone antagonist (e.g. spironolactone or eplerenone). Aldosterone antagonists decrease the morbidity and mortality associated with symptomatic chronic heart failure by reducing the risk of volume overload and increased strain on the heart.
• NICE recommends that calcium channel blockers (except amlodipine) should be avoided in heart failure as they can further depress cardiac function and worsen symptoms by reducing cardiac contractility.
• Mechanical heart valves have a high propensity for clot formation, particularly mitral valves. The patient, therefore, requires dual anticoagulation and antiplatelet. The only drugs licensed for anticoagulation in mechanical heart valves are warfarin and low molecular weight heparin (LWMH).
• A single episode of paroxysmal atrial fibrillation, even if provoked, should still prompt consideration of anticoagulation, due to the risk of another episode occurring and causing a clot, using the CHA 2DS 2-VASc score, due to the risk of recurrence. Direct oral anticoagulants are offered as the first line for reducing this risk e.g. apixaban.
• fondaparinux - low molecular weight heparin used to prevent the development of deep vein thrombosis
• warfarin - now used second-line in the prevention of stroke in atrial fibrillation where a direct oral anticoagulant is contraindicated or not tolerated
• Current NICE guidance recommend 2 weeks of aspirin 300mg OD before consideration of anti-coagulation in cases of ischaemic stroke and atrial fibrillation. Patients would then require lifelong anti-coagulation with either warfarin or a direct oral anti-coagulant to prevent the risk of further strokes.