Øyvind Haugen Lie has studied both benign and life-threatening arrhythmias of right ventricular origin in his PhD thesis.

MAIN RESULTS:

1. 8000 premature ventricular contractions each day could be enough to impair left ventricular function.
2. High exercise intensity predicts life-threatening arrhythmia in arrhytmogenic cardiomyopathy.
3. The combination of electrocardiography, echocardiography and assessment of exercise habits could identify high-risk patients with arrhytmogenic cardiomyopathy.

THESIS DEFENCE:

Thesis: Risk stratification and management of patients with right ventricular arrhythmias
Candidate: Øyvind Haugen Lie
Time: December 11, 2018 at 13:15
Place: Oslo University Hospital, Rikshospitalet: Red auditorium
Link to university website

SUMMARY:

(1) Frequent premature ventricular contractions can impair left ventricular function at a lower threshold than previously suggested. By using speckle tracking echocardiography, Haugen Lie and colleagues found 8000 or more daily premature ventricular contractions to be the optimal threshold to identify patients with reduced global longitudinal strain. This threshold is only one third of the threshold suggested to impair cardiac function in previous studies.

52 patients referred for ablation for benign outflow tract arrhythmia of right ventricular origin were included in the study.

(2) Higher exercise intensity is a strong and independent marker of adverse outcome for patients with arrhythmogenic cardiomyopathy. Patients with this inheritable heart disease could be advised to restrict their exercise intensity, the researchers conclude.

Exercise habits were recorded at the time the 173 patients in the study received the diagnosis of arrhythmogenic cardiomyopathy. Half of them reported high-intensity exercise. 74 % of this half experienced their first life-threatening ventricular arrhythmic event during the next four years, compared to only 20 % of patients who reported low-intensity exercise. Exercise duration was also linked to increased arrhythmia risk. However, exercise intensity was indepentendly associated with almost 4-fold increased risk also after controlling for the interaction with duration of exercise.

(3) Arrythmogenic cardiomyopathy patients with both T-wave inversions ≥V₃ on electrocariography, increased left ventricular mechanical dispersion on echocardiography, and a reported history of high-intensity exercise had a median of 1.2 years from diagnosis to their first life-threatening arrhythmic event. Patients with none of these predictors had minimal risk, whereas the risk was dramatically increased in those with two or three factors.

A total of 117 patients were included in the study and followed for a median of 4.2 years. The results could help identify patients who could benefit from preventive ICD therapy.

REFERENCES:

(1) Lie, Ø. H., Saberniak, J., Dejgaard, L. A., Stokke, M. K., Hegbom, F., Anfinsen, O. G., Edvardsen, T., & Haugaa, K. H. (2017). Lower than expected burden of premature ventricular contractions impairs myocardial function. ESC heart failure, 4(4), 585-594.

(2) Lie, Ø. H., Dejgaard, L. A., Saberniak, J., Rootwelt, C., Stokke, M. K., Edvardsen, T., & Haugaa, K. H. (2018). Harmful effects of exercise intensity and exercise duration in patients with arrhythmogenic cardiomyopathy. JACC: Clinical Electrophysiology, 4(6), 744-753.

(3) Lie, Ø. H., Rootwelt-Norberg, C., Dejgaard, L. A., Leren, I. S., Stokke, M. K., Edvardsen, T., & Haugaa, K. H. (2018). Prediction of life-threatening ventricular arrhythmia in patients with arrhythmogenic cardiomyopathy: a primary prevention cohort study. JACC: Cardiovascular Imaging, 11(10), 1377-1386.