Abstract 13605: Papillary Muscle Hypertrophy is Possibly Associated With the Genesis of J-waves
Background: While the J-waves were associated with vulnerability to ventricular fibrillation, its mechanisms are still under investigation. On the other hand, potential arrhythmogenic roles for the papillary muscle (PM) and false tendon have been discussed and these structures were recognized as the target sites of radiofrequency ablation for ventricular arrhythmias. We recently reported the close relationship between the false tendon and J-waves (Heart Rhythm, 2012). In the present study we investigated the electrocardiographic characteristics in the patients with PM hypertrophy.
Methods: We studied 101 patients with PM hypertrophy detected by echocardiography (PMH group, 66.4±15.0 years, 65 males) and 159 age- and sex- matched control subjects without PMH (control group, 67.4±8.1 years, 104 males). PM hypertrophy was defined as PM with the minimum diameter >10mm in the short axis view at the endodiastole. The patients with organic heart diseases or left ventricular hypertrophy were excluded. The heart rate and PQ, QRS, QTc and JTc intervals were automatically measured and the presence of J-wave was determined in the 12-leads ECGs. The J-wave was defined as terminal QRS notching or slurring with amplitude of over 0.1 mV in at least 2 leads. The left ventricular mass index (LVMI) was calculated by echocardiography.
Results: The incidence of J-wave was significantly higher in PMH group than control group (45% vs 25%, p<0.001). QRS duration (95.1±15.8 vs 89.2±8.8 msec, p<0.0001), QTc (422±17 vs 410±17 msec, p<0.0001) and JTc intervals (322±20 vs 317±21 msec, p<0.05) were significantly longer in PMH group than control group. LVMI was significantly greater in PMH group than control group (103±26 vs 90±21, p<0.0001). Only the presence of PMH was an independent predictive value of the presence of J-waves between age, male sex, LVMI and PMH by multivariate logistic regression analysis (Odds Ratio 2.30, 95%CI 1.31-4.06, p<0.005).
Conclusions: These results suggested that PMH was related to the genesis of J-waves and may have a potential arrhythmogenic property with both conduction and repolarization abnormalities.
- © 2013 by American Heart Association, Inc.