Non-reentrant Ventricular Arrhythmias in Patients with Structural Heart Disease Unrelated to Abnormal Myocardial Substrate: Non-reentrant VT in Structural Heart Disease.

Heart rhythm : the official journal of the Heart Rhythm Society

PubMedID: 24607914

Ellis ER, Shvilkin A, Josephson ME. Non-reentrant Ventricular Arrhythmias in Patients with Structural Heart Disease Unrelated to Abnormal Myocardial Substrate: Non-reentrant VT in Structural Heart Disease. Heart Rhythm. 2014;.
BACKGROUND
Ventricular arrhythmias in the absence of structural heart disease are commonly referred to as "idiopathic". Patients with structural heart disease have ventricular arrhythmias with the same mechanisms and sites of origin as "idiopathic" ventricular arrhythmias but the prevalence of such arrhythmias is not well defined.

OBJECTIVE
To identify the prevalence of non-reentrant ventricular arrhythmias unrelated to abnormal myocardial substrate in patients with structural heart disease and compare these arrhythmias to ventricular arrhythmias in patients with structurally normal hearts.

METHODS
Of 249 consecutive patients referred for ablation of ventricular arrhythmias, 97 patients had non-reentrant arrhythmias unrelated to underlying structural heart disease. Fifty-five patients had structurally normal hearts and forty-two had underlying structural heart disease.

RESULTS
Compared to patients with structurally normal hearts, patients with structural heart disease were more likely to have non-reentrant ventricular arrhythmias unrelated to underlying abnormal myocardial substrate originating from the aortic cusps and LVOT whereas patients without structural heart disease more often had arrhythmias originating in the RVOT. There was a significant increase in the average left ventricular ejection fraction following ablation in patients with structural heart disease.

CONCLUSIONS
Non-reentrant ventricular arrhythmias unrelated to abnormal myocardial substrate are common in patients with structural heart disease and sites of origin differ from those seen in patients with structurally normal hearts. When managing structural heart disease patients with ventricular arrhythmias, a focus on arrhythmia mechanism, origin, and relationship to underlying myocardial substrate may have important implications for future treatment options and patient outcomes.