T Wave Alternans is a Predictor of Death in Patients with Congestive Heart Failure
Simona Sarzi Braga, MD,
Raffaella Vaninetti*, MD, Antonio Laporta, MD, Anna Picozzi, MD, and
Roberto FE Pedretti, MD.
IRCCS Fondazione
Salvatore Maugeri, Divisione di Cardiologia, Istituto Scientifico di Tradate,
Tradate (VA), Italy.
* Ospedale di Circolo di
Varese, Università degli Studi dell’Insubria, Varese (VA), Italy.
Running head: T wave alternans in congestive heart failure
ABSTRACT
Few data are
available about the prognostic role of T wave Alternans in patients with
congestive heart failure. To assess the ability of T wave Alternans, used alone
or in combination with other risk markers, to predict cardiac death in
decompensated patients, we enrolled 46 patients, mean age 59 ± 9, males 89 %,
ischemic etiology 61 %, NYHA class III 35 %, left ventricular ejection fraction 29 ± 7 %.
After 1.6 years follow-up, 7 patients died from cardiac death (16 %), non
sudden in 6 (86 %) and sudden in 1 (14 %). T wave Alternans was positive in 24
(52 %), negative in 13 (28 %), indeterminate in 9 patients (20 %). T wave
Alternans was positive in all patients with events (100 %) but only in 16 of 37
patients without (41 %) (p = 0.02). Other predictors of cardiac death were O2
consumption at the peak of exercise (p = 0.03), standard deviation of all
NN intervals (p = 0.05) and Wedge pressure (p = 0.03). When Receiver Operator
Characteristics curves were calculated, the highest area (0.73) was found for O2
consumption at the peak of exercise considering the single variables and for O2
consumption at the peak of exercise plus T wave Alternans (0.79) for
combination of them; the comparison of the two Receiver Operator
Characteristics curves did not reach statistical difference (p = 0.5). In
conclusion, this is the first study reporting that T wave Alternans can predict
cardiac death, with a marginal additional prognostic power when used in
combination with measurement of O2 consumption at the peak of
exercise.
KEYWORDS
T wave Alternans; congestive heart failure; cardiac death; risk stratification