Injection of cold saline for diagnosis of intramural ventricular arrhythmias

Abstract

Background: The failure to identify a successful target site for catheter ablation despite extensive endocardial and epicardial mapping is a common feature for an intramural site of origin of a ventricular arrhythmia.

Objective: The purpose of this study was to assess whether transient suppression of premature ventricular complexes (PVCs) by injection of cold saline into the distal coronary venous system can identify an intramural focus.

Methods: Cold saline (room temperature) was injected through an irrigated-tip catheter into the distal coronary venous system in a consecutive series of 26 patients with frequent PVCs referred for catheter ablation.

Results: PVCs were temporarily suppressed in 11 of 26 patients during injection of cold saline. Extensive mapping suggested the presence of an intramural site of origin in 9 of 11 patients with PVC suppression by cold saline but in only 1 of 15 patients in whom PVCs were not suppressed. The suppression of PVCs by cold saline was associated with the presence of an intramural PVC focus with an accuracy of 88% (sensitivity 90%, specificity 88%, positive predictive value 82%, negative predictive value 93%, P = .0002).

Conclusion: Temporary suppression of PVCs by cold saline infused into the distal coronary venous system and the perforator veins strongly suggests the presence of an intramural septal focus of the PVCs.

Keywords: Diagnosis; Intramural; Premature ventricular complex; Suppression; Ventricular arrhythmia.