Sa

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Related to sinoatrial: sinoatrial block

SA

The two-character ISO 3166 country code for SAUDI ARABIA.

Sa

1. ISO 3166-1 alpha-2 code for the Kingdom of Saudi Arabia. This is the code used in international transactions to and from Saudi bank accounts.

2. ISO 3166-2 geocode for Saudi Arabia. This is used as an international standard for shipping to Saudi Arabia. Each Saudi province has its own code with the prefix "SA." For example, the code for the Province of Riyadh is ISO 3166-2:SA-01.

3. An abbreviation for a number of corporate structures, including Sociedad Anonima (Spanish) and Societe Anonyme (French).
References in periodicals archive ?
Origin of the sinoatrial and atrioventricular nodal arteries in South Indians: an angiographic study.
Activation of adrenergic receptors located on the cells of the sinoatrial node and of the myocardium results in increased heart rate and contractility.
For over a decade, teams of researchers have worked to create a biological alternative that might help those kinds of patients, trying such approaches as using stem cells to spur the growth of a new sinoatrial node.
AF is defined as a phenomenon of rapid, chaotic electrical impulses in the atria, where the regular electrical impulses generated by the sinoatrial node are overwhelmed by rapid electrical discharges produced in the atria and adjacent pulmonary veins.
The heart's pacemaker, the sinoatrial node, regulates the timing of the phases by sending electrical impulses to the atria and ventricles.
Patients with DLB are frequently diagnosed with cardiovascular autonomic dysfunction and are more susceptible to the side effects of cholinesterase inhibitors, which can increase tremor and exert effects on the sinoatrial (SA) and atrioventricular nodes and result in atrioventricular block or bradycardia; given this, cholinesterase inhibitors should be used with caution (Ballard et al, 2006; Weintraub & Hurtig, 2007).
Among the different available noninvasive techniques used as markers of autonomic modulation of the heart, heart rate variability (HRV) is considered the best for evaluation of the sympatho-vagal balance at the sinoatrial level (7).
A new study by a group led by Catherine Proenza, PhD and Roger Bannister, PhD from the University of Colorado School of Medicine reports that one of the reasons for the age-dependent reduction in maximum heart rate is that aging depresses the spontaneous electrical activity of the heart's natural pacemaker, the sinoatrial node.
The heartbeat originates in the sinoatrial node of the heart's right upper chamber, where pacemaker cells are clustered.
2] (1,7), a disproportionate increase in respiratory frequency (1,5,7,26), and with the shift towards the predominance of the SNS on HR via the sinoatrial node automaticity (26).