Relationship Between Fragmented QRS Complex and Left Ventricular Fibrosis and Function in Patients With Danon Disease

Jiajun Xie; Yang Liu; Xiaoyu Wei; Weitao Ye; Zelan Ma; Guanyu Lu; Zekun Tan; Tingyu Li; Yining Wang; Lei Zhao; Minjie Lu; Xiaohu Li; Yucheng Chen; Hui Liu

doi:10.3389/fcvm.2022.790917

Relationship Between Fragmented QRS Complex and Left Ventricular Fibrosis and Function in Patients With Danon Disease

Front Cardiovasc Med. 2022 Feb 21:9:790917. doi: 10.3389/fcvm.2022.790917. eCollection 2022.

Authors

Jiajun Xie^{1

2}, Yang Liu³, Xiaoyu Wei⁴, Weitao Ye², Zelan Ma⁵, Guanyu Lu², Zekun Tan^{1

2}, Tingyu Li³, Yining Wang⁶, Lei Zhao⁷, Minjie Lu⁸, Xiaohu Li⁹, Yucheng Chen¹⁰, Hui Liu^{1

2

11}

Affiliations

¹ The Second School of Clinical Medicine, Southern Medical University, Guangzhou, China.
² Department of Radiology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.
³ Guangdong Cardiovascular Institute, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.
⁴ Department of Radiology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.
⁵ Department of Radiology, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.
⁶ Department of Radiology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China.
⁷ Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China.
⁸ Department of Magnetic Resonance Imaging, Fuwai Hospital and National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China.
⁹ Department of Radiology, The First Affiliated Hospital of Anhui Medical University, Hefei, China.
¹⁰ Department of Cardiology, West China Hospital, Sichuan University, Chengdu, China.
¹¹ Guangdong Provincial Key Laboratory of Artificial Intelligence in Medical Image Analysis and Application, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China.

Abstract

Background: Fragmented QRS (f-QRS) complex on the surface ECG is a cardiac conduction abnormality that indicates myocardial scarring. The relationship between the f-QRS complex and cardiac status in patients with Danon disease (DD) remains unclear and will be explored in this study.

Methods: Patients with genetically confirmed DD and cardiac magnetic resonance imaging (CMR) examinations were recruited from multiple centers. The number of leads, pattern, score, and segmental distribution of the f-QRS complex were assessed by surface 12-lead ECG. Cardiac status, such as left ventricular (LV) volume, function, and extent of late gadolinium enhancement (LGE), was demonstrated by CMR. The segmental distribution of LGE was also assessed. Correlations between the f-QRS and cardiac status were assessed.

Results: Fifteen patients (14 men) with DD who underwent 12-lead ECG and CMR imaging were included. The f-QRS complex was documented in all patients (n = 15, 100%). Three patterns of f-QRS were found, with the notched R/S pattern (74%) being the most common, followed by fragmented QRS (16%) and various RSR' (11%). The fragmented QRS pattern showed an association with a higher level of myocardial fibrosis (LGE > 35%). The burden of f-QRS in each patient was assessed by the number of leads with f-QRS (median 7, range 2-12) and the f-QRS score (median 9, range 2-33). In the correlation analysis, the f-QRS score was positively correlated with LGE% (r = 0.726, p = 0.002), negatively correlated with LV ejection function (LVEF; r = -0.617, p = 0.014) as evaluated by CMR. In the local distribution, f-QRS score and LGE% were both predominant in the LV free wall but did not correlate well among the anterior, lateral, and inferior segments.

Conclusion: In this DD cohort, the quantitative f-QRS was correlated well with myocardial fibrosis burden and LV dysfunction in general. This finding suggests that f-QRS can be used as a simple screening tool to assess cardiac status in patients with DD.

Keywords: Danon disease; cardiac magnetic resonance imaging (CMR); electrocardiography; fragmented QRS; myocardial fibrosis.