cavotrikuspidalis

Cavotrikuspidalis is a term used to refer to the cavotricuspidisthmus (CTI) region of the right atrium. It denotes a narrow band of myocardial tissue between the ostium of the inferior vena cava and the tricuspid valve annulus. The CTI lies on the inferior portion of the right atrial wall and is bounded by surrounding anatomical landmarks such as the crista terminalis and the Eustachian ridge, separating the smooth posterior sinus venarum from the trabeculated anterior right atrial wall.

Clinical significance of cavotrikuspidalis centers on its role in typical atrial flutter. The CTI region can serve as a substrate for macroreentrant circuits that propagate around the tricuspid annulus. Diagnosis is typically established through electrophysiology studies or characteristic surface ECG findings of atrial flutter. Electrophysiologic mapping can identify CTI-dependent circuits and guide therapy.

Treatment often involves catheter ablation across the CTI to create bidirectional block between the tricuspid annulus and the inferior vena cava ostium, thereby interrupting the flutter circuit. CTI ablation is associated with high acute and long-term success rates and a favorable safety profile. In some cases, antiarrhythmic drugs may be used, but CTI ablation is commonly considered first-line therapy for CTI-dependent typical atrial flutter.

In summary, cavotrikuspidalis describes a key right atrial region implicated in a common form of arrhythmia and is a primary target for ablation in the management of typical atrial flutter. See also atrial flutter, right atrium, catheter ablation, and electrophysiology.