<prompt> Answer this question truthfullyIn what type of patients is Ivabradine indicated for the treatment of chronic stable angina, and what medication is it used as an alternative to?  <response>: <reason> Ivabradine is indicated for the treatment of chronic stable angina in patients who cannot take β-blockers. Ivabradine is a medication that works by selectively inhibiting the If current in the sinoatrial node of the heart, which leads to a reduction in heart rate. This can help to reduce the workload of the heart and improve symptoms of angina, such as chest pain or discomfort. However, β-blockers are typically the first-line treatment for chronic stable angina, as they have been shown to reduce mortality and morbidity in patients with this condition. Ivabradine may be used as an alternative to β-blockers in patients who cannot tolerate these medications due to side effects or other contraindications. 