Tag Archives: CHD

Translation of PQRST wave

  • P wave shows atrial depolarisation as the atria contract
  • QRS complex shows ventricular depolarisation as the ventricles contract and electrical impulse is conducted from the sinoatrial node, down the bundle of His, into the right and left bundle branches and Purkinje fibres.
  • T wave is the repolarisation of the ventricles as the ventricles relax.

Post-MI Care in Primary Care

Patients with a history of myocardial infarction will need appropriate follow-up in primary care to manage risk factors as far as possible, provide patient education and ensure patients are on correct medication.

Patient education to reduce risks of further MIs is important. In particular, patients should be advised to increase their fruit and vegetable intake to at least 5 portions daily, reducing salt and fat intake, adopting a Mediterranean-style diet including consumption of oily fish. Additional supplements of beta carotene, vitamin C or E are not connected with improving outcomes and reducing cardiac risks. NICE guidelines recommend post-MI patients to consume at least 7g of omega-3 fatty acids per week (2-4 portions of oil fish). For patients unable to achieve this, 1g daily omega-3 ester (Omacor) can be prescribed for up to four years for patients who have had an MI in the previous 3 months. Patients should also be advised to reduce their alcohol consumption to low-moderate levels (less than 21 units per week for men and 14 for women).

Obesity needs to be monitored and managed, as this will not only reduce lipid levels as well as blood pressure but also other conditions such as diabetes.

Smoking cessation help should be offered if appropriate. Nicotine replacement therapy is not advised immediately after an MI, but in the long-term continuing to smoke is a serious risk factor.

All post-MI patients should be offered cardiac rehabilitation with an emphasis on exercise. NICE guidelines recommend moderate exercise for 20-30 minutes (enough to feel lightly breathless) five times per week. Brisk walking is ideal. Sexual activity poses no more risk of a further MI, than in a person who had not had an MI. Although when treating erectile dysfunction it is important to remember that PDE5 (phosphodiesterase 5) inhibitors should be avoided in patients using nicorandil, but can be considered in stable patients six months post-MI.

The optimum lipid target is a total cholesterol of <4mmol/l, LDL cholesterol of <2mmol.

A brief anxiety and depression assessment may be required – referring on to mental health services if necessary.

Air travel can be considered three weeks post-MI, and although the DVLA need not necessarily be notified, it is inadvisable to drive in the four weeks immediately post-MI.

Optimum prescribing for post-MI patients includes:

Daily aspirin (proven to reduce death rate by 25%). This is a lifelong treatment and is a first-line drug. Clopidogrel may be prescribed instead of aspirin if a patient has a well-documented hyper-sensitivity. Clopidogrel may be prescribed alongside aspirin for 12 months in patients with non-ST segment elevation acute coronary syndrome.

ACE inhibitors (particularly in patients with left ventricular dysfunction or heart failure), although current NICE guidelines recommend all patients post-MI should be prescribed ACE inhibitors, after checking renal function. If the patient develops a severe cough or oedema, this would need to be reassessed.

Beta-blockers are responsible for a reduction in mortality of up to 25%. New patients may need to be informed that beta blockers can cause lethargy, but this should resolve after a few weeks.

Statins help reduce lipid levels, and it has been found that after five years’ use they prevent further cardiovascular events in 10% of patients. Statins can be started after liver function and CK has been measured to determine the patient’s baseline, although raised liver enzymes should not necessarily rule out the patient from statin therapy. A statin may be augmented by ezetimibe to reduce LDL and total cholesterol.

A low HDL cholesterol (<1mmol/l) is of particular risk to patient with type II diabetes. Fibrates are effective at raising HDL cholesterol.

Particular attention needs to be paid to the patient’s blood pressure – for post-MI patients the target is <130/80mmHg. To achieve this the beta blocker dose may need to be increased or the patient may also require a diuretic or calcium channel blocker.

UK Guidance on Diet could save around 33,000 Lives annually

A study has found if people adhered to the recommended 5 portions of fruit and vegetables each day and reduced their daily intake of salt to 3.5g as well as their saturated fat intake to 3% of their daily energy intake, this could prevent around 33,000 deaths each year. It was calculated that 20,800 coronoary artery disease deaths, 5,876 stroke deaths, amd 6,481 cancer deaths could be prevented each year by following such guidance. Around 12,500 deaths would be in the 75 years and under category.

Scarborough P et al (2010) Modelling the impact of a healthy diet on cardiovascular disease and cancer mortality Journal of Epidemiology and Community Health. Doi:10.1136/jech.2010.114520

Solar UV and Cardiovascular Disease in Women

A study has found that women who had exposure to solar UV light were at reduced risk of developing cardiovascular disease. The study also found that exposure to non-solar UV light increased a woman’s overall risk of dying from cancer.

Yang, L. et al. (2011) Ultraviolet exposure and mortality among women in Sweden. Cancer Epidemiology, Biomarkers and Prevention. 20, 4, 683-690.

Summary of Chest Pain Triage in Primary Care

Urgent referral to A&E is needed for patients presenting with:

  • ACS: crushing/squeezing chest pain at rest, possibly accompanied by nausea, sweating, shortness of breath or dizziness, pain radiation from left arm to jaw may be present.
  • Aortic aneurysm dissection – symptoms include sharp tearing pain, dyspnoea, syncope, a feeling of impending doom.
  • PE – includes symptoms of sharp sudden pain in a patient with a history of recent inactivity/stasis – perhaps recent long-haul travel, recent surgical procedure under general anaesthetic or hospital admission which has restricted normal level of activity, breathlessness.

Chest pain not necessarily requiring urgent transfer to A&E:

  • Angina – similar symptoms to ACS, but pain experienced on exertion and relieved at rest (possibly with a history of CVD). If the patient is unstable patient should be treated along the lines of ACS. Treat initially with GTN.
  • Chest infection/pleurisy; patient will present with pain on moving or breathing, presents as sharp central pain. Patient may also have a fever. This can be safely treated in primary care setting.
  • Pericarditis; again, symptoms as pleurisy, to be treated with NSAIDs if suitable for patient, consider outpatient ECG.
  • GORD – burning pain, retrosternal. May have a long history, possibly associated with particular foods. Not particularly urgent unless presenting with malaena or haematemesis. Patient may require gastroscopy; primary care may involve PPIs or H2 blockers.

It is vital to take a detailed history, as well as appropriate observations (BP, ECG, pulse, respiratory rate, temperature).

P – Provocation/palliation – what triggers the pain? What relieves it?

Q – Quality – what is the pain like? Stabbing, crushing, aching, dull, tearing. Also use pain scale.

R – Radiation – where does the pain begin, and where does it radiate to?

S – Site – what’s the location of the pain?

T – Timing – when did the pain start? What was the duration? How many episodes have there been? When did the episodes start? Is it getting better or worsening?

Also, record any accompanying symptoms such as dizziness, nausea/vomiting/burping, feeling of impending doom, syncope.

Symptoms suggesting ACS need urgent referral to hospital. If this is the case, the patient should be given 300mg aspirin and high-flow oxygen.

Care of the Post-MI Patient in Primary Care

According to the British Heart Foundation (BHF) in 2006 about 1.3 million people in the UK have had an MI, about 4% of men and 2% of women. Because of their medical history, they will need following up in the primary care setting to help reduce the risk of further events; this is done by a combination of patient education, modification of diet and lifestyle as well as regular checks and medication or further interventions.

In primary care, the major risk factors will therefore be addressed; for example, smoking, obesity, diet, inactive lifestyle, hypertension, dyslipidaemia, poorly-controlled diabetes, as well as ensuring the recommended MI prophylactic medications are prescribed.

Many of these interventions are under QOF with points awarded for specific interventions (such as regular blood pressure checks, blood lipid checks, identification of depression, anxiety or related mental illness, as well as therapies such as ACE inhibitors, beta blockers, aspirin, or angiotensin receptor blockers). It is important for all primary care settings to have robust policies in place for the care of post-MI patients as not all standard therapies are covered by QOF.

Because many of the cardiovascular risk factors are reversible, there needs to be an emphasis on patient education and empowerment. This is the most effective intervention and yet, according to the BHF, less than 40% of post-MI patients have access to this. Primary care nurses are well-placed to provide this.