Differential effects of adrenergic antagonists (Carvedilol vs Metoprolol) on parasympathetic and sympathetic activity: a comparison of clinical results
Background. Cardiovascular autonomic neuropathy (CAN) is recognized as a significant health risk, correlating
with risk of heart disease, silent myocardial ischemia or sudden cardiac death. Beta-blockers are often prescribed
to minimize risk.
Objectives. In this second of two articles, the effects on parasympathetic and sympathetic activity of the alpha/ beta-adrenergic blocker, Carvedilol, are compared with those of the selective beta-adrenergic blocker, Metoprolol. Methods: Retrospective, serial autonomic nervous system test data from 147 type 2 diabetes mellitus patients from eight ambulatory clinics were analyzed. Patients were grouped according to whether a beta-blocker was (1) introduced, (2) discontinued or (3) continued without adjustment. Group 3 served as the control.
Results. Introducing Carvedilol or Metoprolol decreased heart rate and blood pressure, and discontinuing them had the opposite effect. Parasympathetic activity increased with introducing Carvedilol. Sympathetic activity increased more after discontinuing Carvedilol, suggesting better sympathetic suppression. With ongoing treatment, resting parasympathetic activity decreased with Metoprolol but increased with Carvedilol.
Conclusion. Carvedilol has a more profound effect on sympathovagal balance than Metoprolol. While both suppress sympathetic activity, only Carvedilol increases parasympathetic activity. Increased parasympathetic activity may underlie the lower mortality risk with Carvedilol.
Beta-blocker, Cardiovascular autonomic neuropathy, Heart rate variability, Patient outcomes, Respiratory analysis, Sympathovagal imbalance
Financial support: None.
Dr. Joe Colombo 240 South Eighth Street Philadelphia, PA, USA 19107 firstname.lastname@example.org
Share this Article
Related Content In Arrhythmia
Bradycardia, Renal Failure, Atrioventricular Nodal Blockade, Shock and Hyperkalaemia Syndrome Involving Digoxin Toxicity: A Case Report
Heart International. 2023;17(1):Online ahead of journal publication
Bradycardia, renal failure, atrioventricular nodal blockade, shock and hyperkalemia (BRASH) syndrome is a rare, often unrecognized but potentially life-threatening clinical entity that is characterized by the pentad of symptoms after which it is named. BRASH syndrome is seen most commonly in the setting of atrioventricular nodal-blocking medications such as beta-blockers and calcium channel blockers.1,2 The synergistic interplay of […]
Radiofrequency Lesion Quality Markers: Current State of Knowledge
European Journal of Arrhythmia & Electrophysiology. 2022;8(1):2-6 DOI: https://doi.org/10.17925/EJAE.2022.8.1.2
Radiofrequency (RF) ablation involves delivering medium-to-high-frequency alternating current, which is electrically conducted to cardiac tissue that constitutes a part of the circuit. The unipolar circuitry contains the generator, transmission lines, catheter, cardiac tissue, interposed tissue and dispersive electrode (ground pad/indifferent electrode). Bipolar systems, whereby the RF current flows between two electrodes, either on the same […]
Remote Monitoring of Cardiac Arrhythmias Using Wearable Digital Technology: Paradigm Shift or Pipe Dream?
European Journal of Arrhythmia & Electrophysiology. 2022;8(1):7-12 DOI: https://doi.org/10.17925/EJAE.2022.8.1.7
Several smart, connected and direct-to-consumer wearable devices capable of detecting cardiac arrhythmias have proliferated in the marketplace in the last decade. Increasingly, these devices are being marketed as “medical grade” in addition to “wellness” devices.1 New iterations of smartwatch and smartphone technology incorporate biosensors and advanced artificial intelligence (AI) algorithms equipped to diagnose cardiac arrhythmias; examples […]
Journal articles and more to your inbox
Get the latest clinical insights from touchCARDIOSign me up!