From the FDA Drug Label
CLINICAL PHARMACOLOGY Mechanism of Action Metoprolol is a beta 1-selective (cardioselective) adrenergic receptor blocker.
Clinical pharmacology studies have demonstrated the beta-blocking activity of metoprolol, as shown by (1) reduction in heart rate and cardiac output at rest and upon exercise, (2) reduction of systolic blood pressure upon exercise, (3) inhibition of isoproterenol-induced tachycardia, and (4) reduction of reflex orthostatic tachycardia
Animal and human experiments indicate that metoprolol slows the sinus rate and decreases AV nodal conduction
The best beta blocker for sinus tachycardia is metoprolol 1, as it has been shown to slow the sinus rate and decrease AV nodal conduction, thus reducing heart rate.
- Metoprolol is a beta 1-selective adrenergic receptor blocker, which means it primarily affects the heart rate and cardiac output.
- It has been demonstrated to reduce heart rate and cardiac output at rest and upon exercise, making it a suitable option for treating sinus tachycardia.
- Atenolol 2 also has a negative chronotropic effect due to beta blockade of the SA node, but the information provided does not directly compare the two drugs in the context of treating sinus tachycardia.
From the Research
For sinus tachycardia, ivabradine is a more effective treatment option than beta blockers, such as metoprolol, due to its ability to reduce heart rate without compromising hemodynamics, as shown in a study published in 2013 3. When considering treatment options for sinus tachycardia, it's essential to weigh the benefits and risks of each medication.
- Ivabradine has been shown to be effective in reducing heart rate and alleviating symptoms in patients with inappropriate sinus tachycardia, with a significant reduction in resting heart rate and an even larger decrease in heart rate during daily activity 3.
- Metoprolol, a beta blocker, can also reduce heart rate, but it may not be as effective in relieving symptoms during exercise or daily activity, and it can cause hypotension or bradycardia in some patients 3.
- A study published in 2016 found that ivabradine is effective and safe in the short- and medium-term treatment of inappropriate sinus tachycardia, with a significant reduction in heart rate and symptoms 4.
- Another study published in 2021 reviewed the pathophysiological basis of inappropriate sinus tachycardia and its management options, including ivabradine, beta blockers, and calcium channel blockers, highlighting the importance of individualized treatment approaches 5.
- While metoprolol may be effective in some cases, the most recent and highest-quality evidence suggests that ivabradine is a better treatment option for sinus tachycardia, particularly in patients who are unresponsive to beta blockers or have contraindications to their use 6.