Analyses & Studies

Focus Healthcare: Blockages in the heart – Now what?

With CT coronary angiograms increasingly becoming the investigation of choice for screening in high-risk individuals and in the evaluation of patients with chest pain, it is useful to understand the implications of abnormal findings and the various management options.

Blockages in the coronary arteries come in various severity of narrowing, extent of distribution and composition of the plaque. An accompanying data included in the reports is the calcium score, a reflection of the hardening in the wall of the coronary artery.

Driving down cardiovascular risk factors

The key is to aggressively control the 4 main modifiable risk factors – smoking, high cholesterol, hypertension and diabetes. To prevent further progression of the disease process, stringent targets of control need to be met.

To achieve this, apart from the usual dietary control and regular physical activity recommendation, I advise the following 3 points to my patients.

1) The LDL-cholesterol targets are dynamic and different from patient to patient. With calcium and plaque disease that is already evident, the targets can be as low as 1.4mmol/l (55mg/dl). Patients can be misguided to just simply adhering to the refence ranges on the blood test results which are general and not individualized.

2) The benefits of medications to control cardiovascular risk factors far outweigh the minor risk posed. Patients do try to delay starting medications and use lifestyle modification to achieve the targets but this is often suboptimal and unsustainable in the long run.

3) Such medications do not pose a ‘chronic addiction’ risk and can be stopped anytime if the patient wishes. However, they do not cure but rather control the cardiovascular risk factors and cessation would mean getting exposed to the preexisting risks again.

Deciding if a stent intervention is needed

As a contemporary interventional cardiologist, the decision to intervene with angioplasty (often stenting) to open the blockages needs a careful discussion of the potential benefits with the patient. While those with severe disease who have angina symptoms or a weakened heart function benefit from such interventions, the role of preventive stenting in otherwise well patients with moderate to severe disease is not established. In such cases, optimal medical therapy as per the prior section is the mainstay of treatment.  The field of coronary interventions has advanced with modern tools to give further treatment directions with best long-term outcomes.

I discuss the following 3 points with my patients.

1) Coronary physiology is the use of a wire with sensors down the blockage to measure the significance of it to decide if an intervention now can reduce the need of an urgent unanticipated intervention downstream.  Such data has been well validated and replaces the visual estimations on angiograms.

2) Coronary imaging is the use of a catheter-based device down the blockage to analyze the characteristics of the plaque to determine the type of preparatory devices needed to modify it before stenting. It also allows for accurate stent diameter and length measurements to optimize the longevity of the stent.

3) Calcium modification tools are available to break up dense calcium rings to allow the stent to expand fully and reduce stent failure rates. These typically involve specialized equipment such as cutting blades and scoring elements mounted on balloons, intravascular lithotripsy balloons and atherectomy devices.

By Dr Pinakin V Parekh, Senior Consultant Cardiologist, The Harley Street Heart & Vascular Centre