Does Lanreotide (Somatostatin analogue) cause bradycardia and is it dangerous?

From the Guidelines

Lanreotide can cause bradycardia (slow heart rate) as a side effect, but the provided evidence does not directly mention lanreotide as a cause of bradycardia, however, somatostatin analogues like octreotide are known to cause bradycardia in approximately 10% of patients taking the medication, as seen in the study 1. For most people, this slowing of the heart rate is mild and not dangerous. However, in certain individuals—particularly those with pre-existing heart conditions, those taking other medications that slow heart rate, or those with electrolyte abnormalities—the bradycardia could potentially become clinically significant. Lanreotide is a somatostatin analog used to treat conditions like acromegaly and neuroendocrine tumors, and it works by inhibiting the release of various hormones, which can affect the heart's electrical conduction system, leading to the decreased heart rate, as mentioned in the study 1. If you're taking lanreotide and experiencing symptoms like dizziness, fatigue, weakness, confusion, or fainting, you should contact your healthcare provider immediately as these could indicate problematic bradycardia. Regular monitoring of heart rate and rhythm is typically recommended for patients on lanreotide, especially when starting treatment or adjusting dosage, as bradycardia can be a symptom of an underlying condition, as discussed in the study 1. Your doctor may need to adjust your dose or consider alternative treatments if the bradycardia becomes significant. Some key points to consider:

• Lanreotide's effect on heart rate is not explicitly mentioned in the provided evidence, but somatostatin analogues are known to cause bradycardia.
• The mechanism of lanreotide can affect the heart's electrical conduction system, leading to decreased heart rate.
• Monitoring of heart rate and rhythm is crucial for patients on lanreotide.
• Symptoms like dizziness, fatigue, weakness, confusion, or fainting should be reported to the healthcare provider immediately.

From the FDA Drug Label

The most common overall cardiac adverse reactions observed in three pooled SOMATULINE DEPOT cardiac studies in patients with acromegaly were sinus bradycardia (12/217,5.5%), bradycardia (6/217,2.8%), and hypertension (12/217,5.5%) [see Adverse Reactions (6. 1)]. In 81 patients with baseline heart rates of 60 beats per minute (bpm) or greater treated with SOMATULINE DEPOT in Study 3, the incidence of heart rate less than 60 bpm was 23% (19/81) as compared to 16% (15/94) of placebo treated patients; 10 patients (12%) had documented heart rates less than 60 bpm on more than one visit The incidence of documented episodes of heart rate less than 50 bpm as well as the incidence of bradycardia reported as an adverse event was 1% in each treatment group. Initiate appropriate medical management in patients who develop symptomatic bradycardia In patients without underlying cardiac disease, SOMATULINE DEPOT may lead to a decrease in heart rate without necessarily reaching the threshold of bradycardia. In patients suffering from cardiac disorders prior to SOMATULINE DEPOT treatment, sinus bradycardia may occur. Care should be taken when initiating treatment with SOMATULINE DEPOT in patients with bradycardia.

Lanreotide can cause a slow heart rate, with the most common cardiac adverse reactions being sinus bradycardia (5.5%) and bradycardia (2.8%).

• The incidence of heart rate less than 60 bpm was 23% in patients treated with lanreotide, compared to 16% in placebo-treated patients.
• The incidence of documented episodes of heart rate less than 50 bpm was 1% in each treatment group.
• Symptomatic bradycardia can occur, and appropriate medical management should be initiated in such cases.
• Patients with underlying cardiac disease are at higher risk of developing sinus bradycardia.
• Care should be taken when initiating treatment with lanreotide in patients with bradycardia 2.

From the Research

Lanreotide and Heart Rate

• Lanreotide is a somatostatin analog used to treat acromegaly, a condition characterized by excessive growth hormone production.
• Studies have investigated the effects of lanreotide on cardiovascular risk factors and cardiac function in patients with acromegaly.
• One study found that lanreotide decreased heart rate in acromegalic patients, with a significant decrease in systolic blood pressure and heart rate at 7 and 14 days after injection 3.
• Another study found that lanreotide improved cardiac morphology and functional abnormalities in acromegaly, including a reduction in left ventricular mass index and an improvement in left ventricular diastolic function 4.

Bradycardia and Lanreotide

• Bradycardia is a heart rate lower than 60 beats per minute, which can be asymptomatic or symptomatic, with symptoms including syncope, dizziness, chest pain, dyspnea, or fatigue.
• Lanreotide has been shown to cause a decrease in heart rate in some studies, which may be a concern for patients with pre-existing bradycardia or those who are prone to developing bradycardia.
• However, the clinical significance of lanreotide-induced bradycardia is not well established, and further studies are needed to determine the risk of bradycardia associated with lanreotide treatment.
• According to recent guidelines, treatment of bradycardia should be based on symptoms and not solely on heart rate, and lanreotide-induced bradycardia should be evaluated and managed accordingly 5, 6.

Key Findings

• Lanreotide can cause a decrease in heart rate in some patients, which may be a concern for those with pre-existing bradycardia or those who are prone to developing bradycardia.
• The clinical significance of lanreotide-induced bradycardia is not well established, and further studies are needed to determine the risk of bradycardia associated with lanreotide treatment.
• Lanreotide has been shown to improve cardiac morphology and functional abnormalities in acromegaly, which may have beneficial effects on cardiovascular outcomes.