Coronary artery narrowings interfere with blood flow to the heart which can cause chest pain and heart attacks. Cardiologists can treat these narrowings with balloons and stents. However, some narrowings can become very calcified and hard making treatment with balloons and stents difficult. Rotational atherectomy is a tool to treat calcific coronary disease. It uses an ablative drill to break down the hardened plaques inside the coronary arteries facilitating subsequent treatment with balloons and stents. However, during this procedure patients can experience a slow heart rate which may compromise procedural safety. Cardiologists may use a temporary pacemaker that is inserted by separately accessing the heart through a large vein usually from the leg. This maintains a safe heart rate throughout the procedure. However, inserting the temporary pacemaker is associated with additional complications. We have developed and propose an alternative strategy to provide a temporary safety pacemaker during rotational atherectomy without the need for inserting an additional pacemaker.

Inclusion Criteria:

• Age 18-90 years
• Undergoing percutaneous coronary intervention for angina or acute coronary syndrome.
• Calcific coronary disease requiring rotational atherectomy

Exclusion Criteria:

• Pre-existing pacemaker or implantable cardioverter defibrillator.
• Mobitz II heart block or complete heart block.

Patients undergoing rotational atherectomy for calcific coronary disease without any exclusion criteria