Ischemic Heart Disease and Atherosclerosis Prevention

ICD 10 code = I20-I25.

Major risk factors for ischaemic cardiovascular and cerebrovascular disease are:

• Diabetes mellitus.
• Hypertension.
• Central obesity (waist circumference): men ≥102 cm, women ≥88 cm.
• Smoking.
• Dyslipidaemia:
  • Total cholesterol >5.0 mmol/L, or
  • LDL >3 mmol/L, or
  • HDL <1 mmol/L in men and <1.2 mmol/L in women.
• Family history of premature cardiovascular disease in first degree male relatives <55 years and in first degree female relatives <65 years.
• Age: men >55 years, women >65 years.
• Psychological stress.

General Measures

Lifestyle modification, especially smoking cessation, is essential and often has greater beneficial impact on prognosis than vascular interventions and medications.

All persons should be encouraged to make the following lifestyle changes as appropriate:

1. Smoking cessation.
2. Weight reduction in overweight patients, i.e. BMI >25 kg/m2.
3. Maintain ideal weight, i.e. BMI <25 kg/m2.
4. Reduce alcohol intake to no more than 2 standard drinks/day
5. Follow a prudent eating plan i.e. low saturated fat, high fibre and unrefined carbohydrates, with adequate fresh fruit and vegetables.
6. Moderate aerobic exercise, e.g. 40 minutes brisk walking at least 3 times a week.

Calculation of Risk of Developing Cardiovascular Disease in 10 years

(in the absence of cardiovascular disease)

Quick Online Calculator

Use our free online calculator to calculate cardiovascular disease risk in the next 10 years.

To derive the absolute risk as the percentage of patients who will have a myocardial infarction over 10 years “manually”, add the points for each risk category (Section A). The risk associated with the total points is then derived from Section B.

S E C T I O N A

Section B

See image below for calculating 10 year risk manually:

Medicine Treatment

Indications for lipid lowering medicine therapy

Patients with any of the following factors are at a relatively high risk for a cardiovascular event and should receive lipid lowering therapy:

• Ischemic Heart Disease
• Peripheral vascular disease
• Atherothrombotic stroke
• Type 2 diabetes with age >40
• Diabetes for >10 years.
• Diabetes with chronic kidney disease (eGFR <60 mL/minute).

Patients with any of the following factors are also potentially at risk for cardiovascular disease (other than the categories above):

• Diabetes mellitus
• Hypertension
• Central obesity: waist circumference ≥94 cm (men) and ≥80 cm (women)
• Smoking
• Age: men >55 years of age, women >65 years of age

These patients should be managed according to their 10–year risk of a cardiovascular event.

Management is based on the patient’s 10-year risk of a cardiovascular event:

• <10% risk: lifestyle modification and risk assess patient every 5 years
• 10–20% risk: lifestyle modification and risk assess patient annually
• ≥20% risk: lifestyle modification and start statin treatment

Lipid lowering medicines should be given to those with a high risk of CVD even if cholesterol is within the desirable range.

HMGCoA reductase inhibitors (statins), as follow

Primary prevention

These are patients with no existing CVD.

Statins indicated if the patient has any of the following:

• Type 2 diabetes with age > 40 years
• Diabetes for > 10 years
• Diabetes with chronic kidney disease
• ≥ 20% 10-year risk of cardiovascular event.

Give: Simvastatin, oral, 10 mg at night.

For patients on protease inhibitors:

• Atorvastatin, oral, 10 mg at night.

Secondary Prevention

These are patients with existing CVD.

Statins indicated if the patient has any of the following:

• Ischaemic heart disease.
• Atherothrombotic stroke.
• Peripheral vascular disease.

Give Simvastatin, oral, 40 mg at night.

If on protease inhibitors:

• Atorvastatin, oral, 10 mg at night.

For patients on Amlodipine (and not protease inhibitors):

• Simvastatin, oral, 10-20 mg at night.

If the patient complains of muscle pain, reduce the dose of simvastatin to 10 mg at night or consult specialist for further management.

Note: Lipid-lowering medicines must always be used in conjunction with ongoing lifestyle modification.

Protease inhibitor-induced dyslipidaemia

Certain antiretroviral medication, particularly protease inhibitors, can cause dyslipidaemia. Fasting lipid levels should be done 3 months after starting lopinavir/ritonavir.

Lopinavir/ritonavir is associated with a higher risk of dyslipidaemia (specifically hypertriglyceraemia) than atazanavir/ritonavir.

Patients at high risk (>20% risk of developing a CVD event in 10 years) should switch to atazanavir/ritonavir and repeat the fasting lipid profile in 3 months.

Patients with persistent dyslipidaemia despite switching, qualify for lipid lowering therapy. Criteria for initiating lipid lowering therapy are the same as for HIV-uninfected patients.

Many statins (including simvastatin) cannot be used with protease inhibitors, as protease inhibitors inhibit the metabolism of the statin resulting in extremely high blood levels.

Patients who fail to respond to lifestyle modification and have dyslipidaemia treat with:

Atorvastatin, oral, 10 mg at night.

Referral

• Random Cholesterol > 7.5 mmol/L.
• Fasting (14hours) triglycerides > 10mmol/L.