Abstract 14418: Microvolt T-wave Alternans in the Management of Adults With Congenital Heart Diseases
Purpose: Sudden cardiac death (SCD) in adults with congenital heart diseases (CHD) is usually caused by ventricular arrhythmia (VA). Microvolt T-wave alternans (MTWA) proved its role in SCD risk stratification. Aim of study: evaluation of spectral MTWA incidence in patients (P) with CHD and determination its association with VA and SCD risk factors.
Methods: Study group: 204P (93men), aged 33,8±11,4yrs with CHD (TGA, UVH, Ebstein, ccTGA, Eisenmenger, DORV, CAT, unoperated and operated ToF) underwent MTWA, ECG, 24h-Holter-ECG, BNP and cardiopulmonary exercise test. Control group:45 adults. MTWA classification: normal: negative(-) and abnormal: positive(+) and indeterminate(ind). Due to similar prognostic significance MTWA(+) and MTWA(ind) were combined into non-negative group(non-).
Results: 31P were MTWA(+), 53P MTWA(ind) and 120P MTWA(-). Due to MTWA(ind-technical reasons) 25P were excluded. MTWA(non-) was more frequent in study group vs. controls (p=0,000001). The highest ratio of MTWA(non-)(87,5%) was in Eisenmenger syndrome. Among patients with MTWA(non-) malignant and potentially malignant VA was more frequent compared to MTWA(-) (p=0,003;p=0,02). Male gender and pulmonary hypertension (PH) were more often in MTWA(non-) vs. MTWA(-)(p=0,005;p=0,00007). MTWA(non-) compared to MTWA(-) had lower: blood saturation (p=0,0003), max oxygen consumption (peakVO2)(p=0,002) and VE/VCO2slope (p=0,01). MTWA(non-) vs. MTWA(-) had higher: BNP (p=0,03) and NYHA (p=0,007). Factors increasing MTWA(non-) incidence are: in univariate logistic regression: PH (OR=24,29), sVT (OR=7,31), VA (OR=3,01), male gender (OR=2,61), NYHA>I (OR=2,06), worse VE/VCO2slope (OR=1,07) and peakVO2 fall (OR=0,92); in multivariate logistic regression: PH (OR=14,16), male gender (OR=10,2), worse VE/VCO2slope (OR=1,06) and peakVO2 fall (OR=0,89).
Conclusions: In adults with CHD abnormal MTWA occurs more often than in healthy population. Probability of this phenomenon increases with malignant ventricular arrhythmia and its fatal risk factors: advanced heart failure and pulmonary hypertension. Incidence of abnormal MTWA is higher in men. MTWA might be of potential role in SCD risk stratification in adults with congenital heart diseases.
- © 2013 by American Heart Association, Inc.