Premature Ventricular Complexes as a Trigger for Ventricular Fibrillation

Electrocardiographic Determinants of the Polymorphic QRS Morphology in Idiopathic Right Ventricular Outflow Tract Tachycardia

“…However, on the basis of our results and previously reported data, 5 the functional block or delayed conduction by rapid firing due to triggered activity or microreentry arising from a single focus led to chaotic conduction, causing PVT/VF without an organic delayed conduction zone. The findings of the shorter PI in the patients with PVT than in those with MVT and the shorter PI during VT than isolated PVCs in the same patients with PVT, both might result from complexes that are impinging on the ventricular refractoriness (producing dispersion of refractoriness) or may be related to a triggered mechanism of initiation 14,15 …”

“…The CI and PI are both well‐known ECG parameters for determining the initiation of VT 12 or a polymorphic QRS morphology 10,13,14 . Although a few studies have examined the relationship of the CI and PI to the initiation of PVT or VF, those results were inconsistent: some studies have demonstrated the importance of a short CI and/or small PI, 10,13 but another study did not find either of them to be important 14 . Recently, several studies also have examined the ECG characteristics of PVT (idiopathic PVT or VF which were triggered by PVCs arising from the RVOT), and attempted to differentiate these PVTs from MVTs 5,7,9 .…”

Psychological vulnerability, ventricular tachyarrhythmias and mortality in implantable cardioverter defibrillator patients: is there a link?

“…Patients with depression and anxiety tend to have impaired vagally mediated baroflex control of the heart and an increase in sympathetic tone, characterized by an increased level of norepinephrine [46], a decrease in heart rate variability [47,48] and abnormal heart rate turbulence [49]. These parameters that reflect imbalance in autonomic tone have been implicated in the onset of cardiac events, including ventricular fibrillation, ventricular arrhythmias and mortality in ICD patients [35,43,50], and in patients postmyocardial i nfarction [49,51].…”

Primary ventricular fibrillation in a patient with mild hypercalcemia

“…The authors report a case of electrical storm possibly related to SQTS taking into account the presence of short QT interval and isoproterenol and quinidine efficacy. 13 However, it is not clear why short QT interval was present only in the first ECG and secondary causes could not be completely ruled out since mild hypercalcemia was present.…”