Heart rate control: Betablockers or Ivabradine therapy before cardiac computed tomography

The primary objective is to determine which type and dose of medication – beta-blockers or ivabradine – most rapidly achieves a ≥10% reduction in heart rate in patients with a resting heart rate above 65 beats per minute undergoing evaluation for asymptomatic or symptomatic ischemic heart disease prior to cardiac CT. This objective addresses the clinical need for optimal heart rate control to improve image quality and diagnostic accuracy during cardiac computed tomography imaging.

The secondary objectives of the study are:

• To assess the development of heart rate reduction during the monitoring period from 0 to 120 minutes following oral tablet administration of the investigational drug.

• To assess the development of heart rate reduction during the monitoring period from 120 to 150 minutes following intravenous administration in patients who do not achieve a heart rate below 60 beats per minute after receiving the oral tablet or placebo.

• To evaluate the frequency and stability of heart rhythm during cardiac CT imaging, measured at the time of contrast administration.

• To monitor the development of adverse events related to the investigational drug.

The sponsor did not provide information regarding the total number of participants enrolled in this clinical trial. The study population includes both **male** and **female** adult and elderly patients diagnosed with **ischemic heart disease**. Participants are individuals scheduled for **cardiac CT scan** who present with **sinus rhythm** and a resting **heart rate** exceeding 65 beats per minute as documented by electrocardiogram. The trial population was selected based on the requirement for competent patients capable of providing written informed consent. The study focuses on patients undergoing evaluation for asymptomatic or symptomatic ischemic heart disease prior to cardiac computed tomography imaging. No information was provided by the sponsor regarding specific lifestyle considerations such as diet, physical activity, or habits of the participants.

This clinical trial investigates the efficacy of different medications in achieving heart rate reduction in patients undergoing evaluation for **ischemic heart disease** prior to **cardiac computed tomography**. The study compares **beta-blockers** (**atenolol** combined with **chlortalidone**, and **metoprolol succinate**) with **ivabradine** to determine which medication most rapidly achieves a reduction in heart rate of at least 10% from baseline. This is a low-intervention clinical trial utilizing medications already in routine clinical practice. All investigational products are administered via **oral use**. The maximum daily dose is 15 mg for ivabradine, 100 mg for atenolol with chlortalidone, and 200 mg for metoprolol succinate. The maximum treatment period for each medication is 1 day.

The primary objective is to determine which type and dose of medication most rapidly achieves a reduction of at least 10% in heart rate in patients with a resting heart rate above 65 beats per minute who have **sinus rhythm**. The primary endpoint measure is the time required to achieve a mean heart rate lowered by 10% from baseline following administration of the study drug. Principal inclusion criteria include patients scheduled for a cardiac CT scan, sinus rhythm with a heart rate exceeding 65 beats per minute documented by **electrocardiogram**, and competent patients who have provided written informed consent.

The estimated recruitment start date is September 2025, with an estimated study completion date of September 2028, indicating an overall trial duration of approximately three years. The expected length of participant involvement is limited to the acute intervention period required to achieve the target heart rate reduction prior to the cardiac CT procedure, with a maximum treatment period of one day per participant.

The clinical trial evaluates three experimental medications administered via oral route for heart rate control prior to cardiac computed tomography. All investigational products are administered orally with a maximum treatment period of one day.

**Ivabradine** is administered in tablet form via **oral route**. The maximum daily dose is **15 mg**, with a maximum total dose of 15 mg administered over the treatment period. The active substance is ivabradine, a chemical compound classified under ATC code C01EB17. This medication serves as one of the test products in the trial for achieving heart rate reduction in patients with resting heart rate above 65 beats per minute.

**Atenolol** in combination with **chlortalidone** is administered in tablet form via oral route. The maximum daily dose is **100 mg**, with a maximum total dose of 100 mg administered over the treatment period. The product contains two active substances: atenolol and chlortalidone, both of chemical origin. Atenolol is classified under ATC code C07AB03. This combination product serves as one of the **beta-blocker** comparator medications in the trial.

**Metoprolol succinate** is administered in prolonged-release tablet form via oral route. The maximum daily dose is **200 mg**, with a maximum total dose of 200 mg administered over the treatment period. The active substance is metoprolol succinate, a chemical compound classified under ATC code C07AB02. This medication serves as an additional beta-blocker comparator in the trial to determine which medication most rapidly achieves at least 10% reduction in heart rate.

The primary endpoint measure is the time to achieve a mean **heart rate** reduction of 10% from baseline following administration of study drug. This assessment will evaluate which type and dose of medication, either **beta-blockers** or **ivabradine**, most rapidly achieves a ≥10% reduction in heart rate in patients with a resting heart rate above 65 beats per minute who are undergoing evaluation for asymptomatic or symptomatic **ischemic heart disease** prior to cardiac computed tomography. Heart rate will be documented by electrocardiogram at baseline, with patients required to have sinus rhythm with a heart rate greater than 65 beats per minute confirmed by ECG prior to enrollment.