LDL goal as a risk factor target in the post-intervention outpatient cardiology population
Authors: Mustafa M , Sanmugathas N , Mcintosh K , Kumar N 
Published: May 2022

Abstract

Funding Acknowledgements
Type of funding sources: None.

Background
The relationship between an acute coronary event and cholesterol levels has been immensely researched, specifically the low-density lipoprotein (LDL) component of cholesterol. According to the Canadian guidelines, LDL cholesterol should be below 1.8 mmol/L if the patient has suffered an acute cardiac event. The European guidelines suggests that LDL target concentration should be below 1.4 mmol/L if the patient has had a previous cardiac event. European guidelines also lowered the LDL recommendations to less than 1 mmol/L if the patient has had 2 previous cardiac event in the previous 2 years.

Purpose
Assess the concordance of one Canadian cardiology clinic to the European LDL guidelines in patients with coronary artery disease.

Methods
Patients were randomly selected from a single centre outpatient Cardiology practice between January and June 2021. All patients were selected by 1 researcher. The patients selected must have been diagnosed with coronary artery disease by Angiography and undergone intervention in the form of percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG). The blood cholesterol levels were evaluated before and after intervention.

Results
101 patients were randomly selected for this study. Data encompassed 83 males and 18 females ages 43 to 88. Before the intervention, 15 patients had an LDL level below 1.4 mmol/L, 29 patients had an LDL level below 1.8 mmol/L. After the intervention, the number of patients with LDL &lt;1.4 mmol/L was 50 and LDL&lt;1.8 was 85. This population was divided by risk factors and the LDL levels were compared before and after intervention. 9 patients were known to be smokers, their LDL levels were on average 2.73 mmol/L before intervention and 1.3 mmol/L after intervention. 31 patients were known diabetic, their LDL levels were on average 2.15 mmol/L before intervention and 1.43 mmol/L after intervention. 69 patients had hypertension, their LDL levels were 2.36 mmol/L before intervention and 1.46 mmol/L after intervention. Of the 30 patient who had a positive family history, the LDL on average was 2.39 mmol/L before intervention and 1.84 mmol/L after intervention. Positive family history was contingent on having an immediate female relative with age &lt;65 or immediate male relative with age &lt;55 having had a cardiac event or coronary intervention.

Conclusions
The number of individuals on appropriate cholesterol medications after intervention increased thereby reducing the LDL concentration. The data shows that in a sample of the typical Canadian population, 84% of patients were adequately managed after a coronary artery intervention according to the Canadian guidelines. According to the UK guidelines, only 29.5% are being adequately managed. The North American guidelines will likely incorporate the new LDL targets into upcoming revisions and therefore more aggressive risk factor management will be required to meet the new target goals.