Abstract 17232: Different Clinical Significance of Prolonged and Fragmented QRS in Hypertrophic Cardiomyopathy
Background: Prolonged QRS duration (pQRS) and fragmented QRS (fQRS) are reported to have associations with severe arrhythmia events or heart failure (HF). However, controversy exists regarding the clinical significance of pQRS or fQRS, particularly its relationship in HCM patients.
Objectives: We aimed to explore the clinical significance of pQRS and fQRS and their contribution to clinical outcomes using biomarkers and cardiac magnetic resonance (CMR) testing in HCM patients.
Methods: 137 HCM patients receiving regular outpatient treatment underwent 12-lead ECG and CMR (cine and late gadolinium enhancement imaging). QRS duration was measured by automatic analysis, and pQRS were defined as >120 msec. fQRS was defined as the presence of ≥1 additional R wave (R’) or notch on the R/S waves in ≥2 contiguous leads. Left ventricular (LV) mass and fibrosis was quantified and plasma BNP level was measured in a week around CMR testing.
Results: pQRS and fQRS were observed in 19 % and 50 % of HCM patients, respectively. fQRS was associated with longer QRS duration only in patients with non-pQRS (P<0.01). pQRS was associated with NYHA class ≥2, increased BNP level, or decreased ejection fraction (EF) (all, P <0.05). The correlation between QRS duration and LV end-diastolic volume index (EDVI) was also observed (R=0.276, P <0.01), and the both were independently associated with history of HF admission (P <0.01). In contrast, fQRS was not associated with increased EDVI, decreased EF, increased fibrosis mass, or NYHA class ≥2. Furthermore, in Kaplan-Meier survival analysis, the detection of fQRS did not predict the clinical outcomes during a median follow-up of 16.0 months.
Conclusions: Prolonged QRS duration was associated with LV remodeling and HF in patients with HCM. In contrast, fragmented QRS had limited values as the predictors of clinical manifestations and outcomes.
Author Disclosures: T. Nakamura: None. Y. Iwanaga: None. Y. Kagioka: None. T. Kawamura: None. M. Yasuda: None. R. Yasuoka: None. T. Kurita: None. S. Miyazaki: None.
- © 2016 by American Heart Association, Inc.