One way to assess for digoxin toxicity is by examining the patient’s electrocardiogram (ECG) for specific characteristics. In the case of digoxin toxicity, ECG findings may include downsloping ST depression, prolonged QT interval, tall tented T-waves, and possibly delta waves. However, a short PR interval (< 120ms) is not typically associated with digoxin toxicity. Further Reading: Digoxin is a medication used for rate control in atrial fibrillation and for improving symptoms in heart failure. It works by decreasing conduction through the atrioventricular node and increasing the force of cardiac muscle contraction. However, digoxin toxicity can occur, and plasma concentration alone does not determine if a patient has developed toxicity. Symptoms of digoxin toxicity include feeling generally unwell, lethargy, nausea and vomiting, anorexia, confusion, yellow-green vision, arrhythmias, and gynaecomastia. ECG changes seen in digoxin toxicity include downsloping ST depression with a characteristic Salvador Dali sagging appearance, flattened, inverted, or biphasic T waves, shortened QT interval, mild PR interval prolongation, and prominent U waves. There are several precipitating factors for digoxin toxicity, including hypokalaemia, increasing age, renal failure, myocardial ischaemia, electrolyte imbalances, hypoalbuminaemia, hypothermia, hypothyroidism, and certain medications such as amiodarone, quinidine, verapamil, and diltiazem. Management of digoxin toxicity involves the use of digoxin specific antibody fragments, also known as Digibind or digifab. Arrhythmias should be treated, and electrolyte disturbances should be corrected with close monitoring of potassium levels. It is important to note that digoxin toxicity can be precipitated by hypokalaemia, and toxicity can then lead to hyperkalaemia.

The majority of dissections happen in individuals between the ages of 40 and 70, with the highest occurrence observed in the age group of 50 to 65.

Further Reading:

Aortic dissection is a life-threatening condition in which blood flows through a tear in the innermost layer of the aorta, creating a false lumen. Prompt treatment is necessary as the mortality rate increases by 1-2% per hour. There are different classifications of aortic dissection, with the majority of cases being proximal. Risk factors for aortic dissection include hypertension, atherosclerosis, connective tissue disorders, family history, and certain medical procedures.

The presentation of aortic dissection typically includes sudden onset sharp chest pain, often described as tearing or ripping. Back pain and abdominal pain are also common, and the pain may radiate to the neck and arms. The clinical picture can vary depending on which aortic branches are affected, and complications such as organ ischemia, limb ischemia, stroke, myocardial infarction, and cardiac tamponade may occur. Common signs and symptoms include a blood pressure differential between limbs, pulse deficit, and a diastolic murmur.

Various investigations can be done to diagnose aortic dissection, including ECG, CXR, and CT with arterial contrast enhancement (CTA). CT is the investigation of choice due to its accuracy in diagnosis and classification. Other imaging techniques such as transoesophageal echocardiography (TOE), magnetic resonance imaging/angiography (MRI/MRA), and digital subtraction angiography (DSA) are less commonly used.

Management of aortic dissection involves pain relief, resuscitation measures, blood pressure control, and referral to a vascular or cardiothoracic team. Opioid analgesia should be given for pain relief, and resuscitation measures such as high flow oxygen and large bore IV access should be performed. Blood pressure control is crucial, and medications such as labetalol may be used to reduce systolic blood pressure. Hypotension carries a poor prognosis and may require careful fluid resuscitation. Treatment options depend on the type of dissection, with type A dissections typically requiring urgent surgery and type B dissections managed by thoracic endovascular aortic repair (TEVAR) and blood pressure control optimization.

Aortic stenosis can be identified through various clinical signs. These signs include a slow rising and low-volume pulse, as well as a narrow pulse pressure. The ejection systolic murmur, which is loudest in the aortic area (2nd intercostal space, close to the sternum), is another indicator. Additionally, a sustained apex beat and a thrill in the aortic area can be felt when the patient is sitting forward at the end of expiration. In some cases, a 4th heart sound may also be present. It is important to note that in severe cases of aortic stenosis, there may be reverse splitting of the second heart sound. However, fixed splitting of the 2nd heart sound is typically associated with ASD and VSD. Lastly, the presence of an ejection click can help exclude supra- or subaortic stenosis, especially if the valve is pliable.

The clinical symptoms of mitral stenosis include shortness of breath, which tends to worsen during exercise and when lying flat. Tiredness, palpitations, ankle swelling, cough, and haemoptysis are also common symptoms. Chest discomfort is rarely reported.

The clinical signs of mitral stenosis can include a malar flush, an irregular pulse if atrial fibrillation is present, a tapping apex beat that can be felt as the first heart sound, and a left parasternal heave if there is pulmonary hypertension. The first heart sound is often loud, and a mid-diastolic murmur can be heard best at the apex in the left lateral position during expiration using the bell of the stethoscope.

Mitral stenosis is typically caused by rheumatic heart disease, with about two-thirds of patients being female. During pregnancy, the increase in plasma volume can lead to elevated left atrial and pulmonary venous pressures. This can exacerbate any symptoms related to mitral stenosis and potentially result in pulmonary edema, as seen in this case.

This patient’s medical history suggests a diagnosis of acute coronary syndrome. It is important to provide pain relief as soon as possible. This can be achieved by administering GTN (sublingual or buccal), but if there is suspicion of an acute myocardial infarction (MI), intravenous opioids such as morphine should be offered.

Aspirin should be given to all patients with unstable angina or NSTEMI as soon as possible and should be continued indefinitely, unless there are contraindications such as a high risk of bleeding or aspirin hypersensitivity. A single loading dose of 300 mg should be given immediately after presentation.

For patients without a high risk of bleeding and no planned coronary angiography within 24 hours of admission, fondaparinux should be administered. However, if coronary angiography is planned within 24 hours, unfractionated heparin can be offered as an alternative to fondaparinux. For patients with significant renal impairment (creatinine above 265 micromoles per litre), unfractionated heparin should be considered, with dose adjustment based on clotting function monitoring.

Routine administration of oxygen is no longer recommended, but oxygen saturation should be monitored using pulse oximetry as soon as possible, preferably before hospital admission. Supplemental oxygen should only be given to individuals with an oxygen saturation (SpO2) below 94% who are not at risk of hypercapnic respiratory failure, aiming for an SpO2 of 94-98%. For individuals with chronic obstructive pulmonary disease at risk of hypercapnic respiratory failure, a target SpO2 of 88-92% should be achieved until blood gas analysis is available.

Bivalirudin, a specific and reversible direct thrombin inhibitor (DTI), is recommended by NICE as a potential treatment for adults with STEMI undergoing percutaneous coronary intervention.

For more information, refer to the NICE guidelines on the assessment and diagnosis of chest pain of recent onset.

A collapsing pulse, also known as a water hammer pulse, is a common clinical feature associated with aortic regurgitation (AR). In AR, the pulse rises rapidly and forcefully before quickly collapsing. This pulsation pattern may also be referred to as Watson’s water hammer pulse or Corrigan’s pulse. Heart sounds in AR are typically quiet, and the second heart sound (S2) may even be absent if the valve fails to fully close. A characteristic early to mid diastolic murmur is often present. Other typical features of AR include a wide pulse pressure, a mid-diastolic Austin-Flint murmur in severe cases, a soft S1 and S2 (with S2 potentially being absent), a hyperdynamic apical pulse, and signs of heart failure such as lung creases, raised jugular venous pressure (JVP), and tachypnea.

Further Reading:

Valvular heart disease refers to conditions that affect the valves of the heart. In the case of aortic valve disease, there are two main conditions: aortic regurgitation and aortic stenosis.

Aortic regurgitation is characterized by an early diastolic murmur, a collapsing pulse (also known as a water hammer pulse), and a wide pulse pressure. In severe cases, there may be a mid-diastolic Austin-Flint murmur due to partial closure of the anterior mitral valve cusps caused by the regurgitation streams. The first and second heart sounds (S1 and S2) may be soft, and S2 may even be absent. Additionally, there may be a hyperdynamic apical pulse. Causes of aortic regurgitation include rheumatic fever, infective endocarditis, connective tissue diseases like rheumatoid arthritis and systemic lupus erythematosus, and a bicuspid aortic valve. Aortic root diseases such as aortic dissection, spondyloarthropathies like ankylosing spondylitis, hypertension, syphilis, and genetic conditions like Marfan’s syndrome and Ehler-Danlos syndrome can also lead to aortic regurgitation.

Aortic stenosis, on the other hand, is characterized by a narrow pulse pressure, a slow rising pulse, and a delayed ESM (ejection systolic murmur). The second heart sound (S2) may be soft or absent, and there may be an S4 (atrial gallop) that occurs just before S1. A thrill may also be felt. The duration of the murmur is an important factor in determining the severity of aortic stenosis. Causes of aortic stenosis include degenerative calcification (most common in older patients), a bicuspid aortic valve (most common in younger patients), William’s syndrome (supravalvular aortic stenosis), post-rheumatic disease, and subvalvular conditions like hypertrophic obstructive cardiomyopathy (HOCM).

Management of aortic valve disease depends on the severity of symptoms. Asymptomatic patients are generally observed, while symptomatic patients may require valve replacement. Surgery may also be considered for asymptomatic patients with a valvular gradient greater than 40 mmHg and features such as left ventricular systolic dysfunction. Balloon valvuloplasty is limited to patients with critical aortic stenosis who are not fit for valve replacement.

For patients suspected of having acute coronary syndromes (ACS), it is recommended that they receive 300 mg of aspirin and pain relief in the form of glyceryl trinitrate (GTN) with the option of intravenous opioids such as morphine. However, if the patient is pain-free after taking GTN, there is no need to administer morphine. The next steps in medical management or intervention will be determined once the diagnosis is confirmed.

Further Reading:

Acute Coronary Syndromes (ACS) is a term used to describe a group of conditions that involve the sudden reduction or blockage of blood flow to the heart. This can lead to a heart attack or unstable angina. ACS includes ST segment elevation myocardial infarction (STEMI), non-ST segment elevation myocardial infarction (NSTEMI), and unstable angina (UA).

The development of ACS is usually seen in patients who already have underlying coronary heart disease. This disease is characterized by the buildup of fatty plaques in the walls of the coronary arteries, which can gradually narrow the arteries and reduce blood flow to the heart. This can cause chest pain, known as angina, during physical exertion. In some cases, the fatty plaques can rupture, leading to a complete blockage of the artery and a heart attack.

There are both non modifiable and modifiable risk factors for ACS. non modifiable risk factors include increasing age, male gender, and family history. Modifiable risk factors include smoking, diabetes mellitus, hypertension, hypercholesterolemia, and obesity.

The symptoms of ACS typically include chest pain, which is often described as a heavy or constricting sensation in the central or left side of the chest. The pain may also radiate to the jaw or left arm. Other symptoms can include shortness of breath, sweating, and nausea/vomiting. However, it’s important to note that some patients, especially diabetics or the elderly, may not experience chest pain.

The diagnosis of ACS is typically made based on the patient’s history, electrocardiogram (ECG), and blood tests for cardiac enzymes, specifically troponin. The ECG can show changes consistent with a heart attack, such as ST segment elevation or depression, T wave inversion, or the presence of a new left bundle branch block. Elevated troponin levels confirm the diagnosis of a heart attack.

The management of ACS depends on the specific condition and the patient’s risk factors. For STEMI, immediate coronary reperfusion therapy, either through primary percutaneous coronary intervention (PCI) or fibrinolysis, is recommended. In addition to aspirin, a second antiplatelet agent is usually given. For NSTEMI or unstable angina, the treatment approach may involve reperfusion therapy or medical management, depending on the patient’s risk of future cardiovascular events.

Anaphylaxis, also known as anaphylactic shock, is characterized by certain symptoms similar to other types of shock. These symptoms include low blood pressure (hypotension), rapid heart rate (tachycardia), irregular heart rhythm (arrhythmia), changes in the electrocardiogram (ECG) indicating reduced blood flow to the heart (myocardial ischemia), such as ST elevation, and in severe cases, cardiac arrest.

Further Reading:

Anaphylaxis is a severe and life-threatening hypersensitivity reaction that can have sudden onset and progression. It is characterized by skin or mucosal changes and can lead to life-threatening airway, breathing, or circulatory problems. Anaphylaxis can be allergic or non-allergic in nature.

In allergic anaphylaxis, there is an immediate hypersensitivity reaction where an antigen stimulates the production of IgE antibodies. These antibodies bind to mast cells and basophils. Upon re-exposure to the antigen, the IgE-covered cells release histamine and other inflammatory mediators, causing smooth muscle contraction and vasodilation.

Non-allergic anaphylaxis occurs when mast cells degrade due to a non-immune mediator. The clinical outcome is the same as in allergic anaphylaxis.

The management of anaphylaxis is the same regardless of the cause. Adrenaline is the most important drug and should be administered as soon as possible. The recommended doses for adrenaline vary based on age. Other treatments include high flow oxygen and an IV fluid challenge. Corticosteroids and chlorpheniramine are no longer recommended, while non-sedating antihistamines may be considered as third-line treatment after initial stabilization of airway, breathing, and circulation.

Common causes of anaphylaxis include food (such as nuts, which is the most common cause in children), drugs, and venom (such as wasp stings). Sometimes it can be challenging to determine if a patient had a true episode of anaphylaxis. In such cases, serum tryptase levels may be measured, as they remain elevated for up to 12 hours following an acute episode of anaphylaxis.

The Resuscitation Council (UK) provides guidelines for the management of anaphylaxis, including a visual algorithm that outlines the recommended steps for treatment.
https://www.resus.org.uk/sites/default/files/2021-05/Emergency%20Treatment%20of%20Anaphylaxis%20May%202021_0.pdf

Tricuspid regurgitation is characterized by a continuous murmur that spans the entire systolic phase of the cardiac cycle. This murmur is best audible at the lower left sternal edge and has a low frequency. Interestingly, the intensity of the murmur increases during inspiration and decreases during expiration, a phenomenon referred to as Carvallo’s sign.

Further Reading:

Tricuspid regurgitation (TR) is a condition where blood flows backwards through the tricuspid valve in the heart. It is classified as either primary or secondary, with primary TR being caused by abnormalities in the tricuspid valve itself and secondary TR being the result of other conditions outside of the valve. Mild TR is common, especially in young adults, and often does not cause symptoms. However, severe TR can lead to right-sided heart failure and the development of symptoms such as ascites, peripheral edema, and hepatomegaly.

The causes of TR can vary. Primary TR can be caused by conditions such as rheumatic heart disease, myxomatous valve disease, or Ebstein anomaly. Secondary TR is often the result of right ventricular dilatation due to left heart failure or pulmonary hypertension. Other causes include endocarditis, traumatic chest injury, left ventricular systolic dysfunction, chronic lung disease, pulmonary thromboembolism, myocardial disease, left to right shunts, and carcinoid heart disease. In some cases, TR can occur as a result of infective endocarditis in IV drug abusers.

Clinical features of TR can include a pansystolic murmur that is best heard at the lower left sternal edge, Carvallo’s sign (murmur increases with inspiration and decreases with expiration), an S3 heart sound, and the presence of atrial arrhythmias such as flutter or fibrillation. Other signs can include giant C-V waves in the jugular pulse, hepatomegaly (often pulsatile), and edema with lung crepitations or pleural effusions.

The management of TR depends on the underlying cause and the severity of the condition. In severe cases, valve repair or replacement surgery may be necessary. Treatment may also involve addressing the underlying conditions contributing to TR, such as managing left heart failure or pulmonary hypertension.

Pericarditis refers to the inflammation of the pericardium, which can be caused by various factors such as infections (typically viral, like coxsackie virus), drug-induced reactions (e.g. isoniazid, cyclosporine), trauma, autoimmune conditions (e.g. SLE), paraneoplastic syndromes, uremia, post myocardial infarction (known as Dressler’s syndrome), post radiotherapy, and post cardiac surgery.

The clinical presentation of pericarditis often includes retrosternal chest pain that worsens with lying flat and improves when sitting forwards, along with shortness of breath, rapid heartbeat, and the presence of a pericardial friction rub.

Characteristic electrocardiogram (ECG) changes associated with pericarditis typically show widespread concave or ‘saddle-shaped’ ST elevation, widespread PR depression, reciprocal ST depression and PR elevation in aVR (and sometimes V1), and sinus tachycardia is commonly observed.