Use of NOACS in high-risk patients with atrial fibrillation in Saudi Arabia: Perspectives on improving patient care.

BACKGROUND: Despite the widespread and increasing use of NOACs in Saudi Arabia, there is a lack of contemporary guidance specific to the region. In particular, guidance on NOAC use in high-risk patients who are more likely to experience bleeding with oral anticoagulant therapy is needed. There is an unmet need for a review of contemporary evidence coupled with expert insights on safe and effective NOAC use in high-risk patients with AF in Saudi Arabia. RESEARCH DESIGN AND METHODS: This article provides a detailed review of contemporary literature on NOAC use in high-risk patients with AF. Additionally, key gaps in the literature are identified and expert insights are shared to guide effective management of patients and the significance of local data is evaluated with respect to challenges in optimizing the use of NOACs. CONCLUSIONS: This article provides information that complements and expands on existing reviews and guidelines on NOAC use in patients with AF, with a focus on challenges specific to the Saudi Arabian context with the potential to make a positive contribution to the medical community in Saudi Arabia and in other nations.

Simultaneous antegrade dual AV node conduction initiates AV nodal re-entrant tachycardia (a rare initiation mechanism).

Typical atrioventricular nodal reentrant tachycardia (AVNRT) is the most common paroxysmal supraventricular tachycardia among adults. The concept of dual pathway physiology remains widely accepted, although this physiology likely results from the functional properties of anisotropic tissue within the triangle of Koch, rather than anatomically distinct tracts of conduction. AVNRT is typically induced with anterograde block over the fast pathway and conduction over the slow pathway, with subsequent retrograde conduction over the fast pathway. On rare occasions, anterograde AV node conduction occurs simultaneously through fast and slow pathways resulting in two ventricular beats in response to one atrial beat. We report a case of AVNRT where the tachycardia is always induced by the same mechanism described above. Successful ablation was achieved by slow pathway modification.

The practical approach to discerning between atrial lead displacement and reversal in dual chamber pacemakers.

We describe a 12-lead electrocardiogram image of a pacemaker malfunction due to atrial lead displacement. Facilitating the understanding of pacemaker timing cycles could explain the underlying mechanisms in this instance. This review utilizes the feature of the ventricular safety pacing interval to discern between atrial lead displacement and reversal.

The ECG role in identifying the etiology of tachycardia-induced cardiomyopathy (TIC).

Tachycardia-induced cardiomyopathy (TIC) is a well recognized entity of heart failure (HF) and various mechanisms due to tachyarrhythmias have been postulated to be responsible for impaired cardiac contractility. Previously reported cases showed reversibility of such disorders whenever stable cardiac rhythm is maintained adequately and we report on a 16-year-old boy who has been diagnosed to have TIC, which was misinterpreted initially as sinus tachycardia secondary to dilated cardiomyopathy and heart failure. A complete recovery of his left ventricular function was achieved by radiofrequency catheter ablation and highlights the importance of a 12-lead electrocardiogram (ECG) assessment in such patients.

Coronary sinus diverticulum as a cause of resistant posteroseptal pathway ablation.

Coronary sinus (CS) anomalies such as diverticulum, persistent left superior vena cava or CS ostium dilatation are predominantly found in patients with accessory pathway-related tachycardias. Diverticulum of the proximal CS found in 7-11% of patients with postero-septal or left posterior manifests accessory pathways. We reported a 28 year old gentleman with manifested postero-septal accessory pathway, who underwent repeat electrophysiological study (EPS) and radiofrequency ablation for previously failed ablation. Huge CS diverticulum was identified by angiography as a reason for resistant accessory pathway. Successful RF ablation was achieved at the neck of the diverticulum without complications. Other associated anomalies were ruled out by cardiac computerized tomography (CT) and trans-esophageal echocardiography.

The importance of utilizing 24-h Holter monitoring as a non-invasive method of predicting the mechanism of supraventricular tachycardia.

Despite the emergence of advanced invasive technology in identifying the various types of arrhythmia mechanisms, 24-h ambulatory electrocardiogram monitoring as a non-invasive method remains an invaluable informative tool in delineating such mechanisms. Furthermore, one observational study has supported the utilization of 24-h Holter monitoring in exploring AV Node (AVN) characteristics sufficiently in correlation with invasive studies when limited to patients without Wolf Parkinson White syndrome showing a positive predictive value of 98% in their supraventricular tachycardia (SVT) assessment (Fukuda et al., 2005). We describe in this report suspected tachycardia initiation mechanism in three SVT cases based on 24-h Holter recordings. Premature atrial contraction with subsequent AVN fast pathway conduction block initiated the common type AVN re-entrant tachycardia (AVNRT). Dual AVN physiology was documented during the electrophysiological studies in all three cases and a definitive therapy was achieved by the AVN slow pathway modification.

Controlling rate and rhythm increases feasibility of CT angiography in atrial fibrillation.

A woman, aged 48 years, with severe rheumatic mitral stenosis and uncontrolled permanent atrial fibrillation (AF) underwent preoperative assessment of coronary arteries. Invasive coronary angiography was not possible because of occluded common iliac artery and bilateral radial spasm. Transesophageal echocardiogram showed a very large mobile left atrial appendage clot, precluding cardioversion. The severe motion artifacts during cardiac CT angiography (64 slices) due to atrial fibrillation were overcome by controlling rhythm and rate through insertion of a temporary pacemaker via right femoral vein, and slowing heart rate below 65 beats per minute by intravenous metoprolol (25 mg) and verapamil (5 mg). Clear pictures of all coronary arteries as well as the left atrial appendage clot were obtained. The temporary pacemaker was removed after eight hours. Uneventful mechanical mitral valve replacement and maze procedure were performed and the patient was discharged in a stable condition.