Radionuclide Assessment of Cardiac Function and Dyssynchrony in Children with Idiopathic Ventricular Tachycardia

Phase analysis for ventricular arrhythmia prediction: A retrospective monocentric cohort study

BACKGROUND

Prediction of ventricular arrhythmias (VA) mostly relies on left ventricular ejection fraction (LVEF), but with limited performance. New echocardiographic parameters such as mechanical dispersion have emerged, but acoustic window sometimes precludes this measurement. Nuclear imaging may be an alternative. We aimed to assess the ability of mechanical dispersion, measured with phase standard deviation (PSD) on radionuclide angiocardiography (RNA), to predict VAs.

METHODS

This retrospective monocentric observational study included all patients who underwent a tomographic RNA from 2015 to 2019. Phase analysis yielded PSD and follow-up was examined to identify VAs, heart transplantation, and death.

RESULTS

The study population consisted of 937 patients, mainly with LVEF ≤ 35% (425, 45%). Most had ischemic (334, 36%) or dilated cardiomyopathies (245, 26%). We identified 86 (9%) VAs. PSD was strongly associated with the occurrence of VA [hazard ratio per 10 ms increase (HR10) 1.12 (1.09-1.16)], heart transplantation [HR10 1.09 (1.06-1.12)], and death [HR10 1.03 (1.00-1.05)]. The association between PSD and VA persisted after adjustment for age, sex, QRS duration, LVEF, global longitudinal strain (GLS), and echocardiography-assessed mechanical dispersion.

CONCLUSION

The occurrence of ventricular arrhythmias was predicted by mechanical dispersion assessed by RNA, even after adjustment for LVEF and GLS.

Efficacy and Safety of Anticoagulant Therapy in Patients With Various Forms of Atrial Fibrillation After Interventional Treatment. Results of a Three-Year Follow-up

Aim      To evaluate efficacy and safety of the anticoagulant therapy in patients with atrial fibrillation (AF) during a 36-month follow-up after an interventional treatment.Material and methods  This study included 302 patients aged 29 to 81 years with various forms of AF. Catheter ablation (CA) of AF foci was performed for all patients. The patients were divided into 3 groups: group 1 with paroxysmal AF, group 2 with persistent AF, and group 3 with longstanding persistent AF. Two subgroups were isolated in each group, with effective and ineffective CA. Results of the follow-up were analyzed at 12, 24, and 36 months after discharge from the hospital. The follow-up interview recorded complaints of palpitation attacks, effectiveness of administered CA, compliance with the treatment, adverse clinical outcomes, including thromboembolic complications (TEC), bleeding, and hospitalizations.Results Efficacy of the interventional treatment for 36 months was 65.3 % in patients with paroxysmal AF, 59.7 % in patients with persistent AF, and 57.1 % in patients with longstanding persistent AF. Patients with paroxysmal AF and effective CA had no adverse events throughout the same period during the antithrombotic treatment (ATT). In contrast, the group with ineffective ablation had both TEC and hemorrhagic complications during the ATT. In the group with persistent AF and effective CA throughout the follow-up period, TECs were less frequent than in the group of ineffective ablations during the ATT treatment. Patients with longstanding persistent AF and effective CA throughout the follow-up period, had no TECs in contrast to patients with ineffective ablation during the ATT treatment. There were no fatal outcomes in patients with effective procedure.Conclusion      A successful CA procedure for AF provides a significant decrease in the risk of ischemic stroke. Furthermore, the invasive strategy does not increase the risk of major and minor bleedings.

NUCLEAR IMAGING IN SUDDEN CARDIAC DEATH RISK ASSESSMENT

Sudden cardiac death is a cause of fatal outcomes in large proportion of cardiovascular patients. Left ventricle ejection fraction at the moment is the main criteria for sudden cardiac death risk stratification, however the parameter is not enough reliable. Nuclear imaging methods make it to visualize finer pathophysiological processes representing the probability of the life threatening ventricular arrhythmias development. The review is focused on recent data on nuclear imaging for cellular perfusion assessment, transient ischemia, vitality of myocardium and myocardial blood flow, metabolic disorders and sympathetic innervation.