Relation of T-wave alternans to mortality and nonsustained ventricular tachycardia in patients with non-ST-segment elevation acute coronary syndrome from the MERLIN-TIMI 36 trial of ranolazine versus placebo.
We explored the utility of T-wave alternans (TWA) in predicting mortality in patients with non-ST-segment elevation acute coronary syndrome (NSTEACS). Maximum TWA was calculated using Modified Moving Average method from continuous electrocardiographic recordings in patients with left ventricular ejection fraction <40% and ventricular tachycardia (VT) ≥4 beats during index hospitalization or sudden cardiac death during the follow-up year and age- and sex-matched controls in the Metabolic Efficiency with Ranolazine for Less Ischemia in Non-ST Elevation Acute Coronary Syndrome-Thrombolysis In Myocardial Infarction (MERLIN-TIMI) 36 trial. All patients received standard therapy for NSTEACS plus ranolazine (n = 109) or placebo (n = 101). Median follow-up was 1 year. Baseline clinical characteristics did not differ between patients with elevated TWA (≥47 μV) compared with lower levels. Patients with TWA ≥47 μV at admission had increased risk of total mortality (adjusted odds ratio [ORadj] 2.35, p = 0.04) during follow-up and VT ≥4 beats (ORadj 2.70, p = 0.01) during hospitalization with a trend toward increased cardiovascular death risk (ORadj 2.18, p = 0.07) during follow-up. In patients receiving placebo, TWA ≥47 μV on day 6 was associated with increased risk of total mortality (OR 4.12, 95% confidence interval 1.25 to 13.64, p = 0.02) and cardiovascular death (OR 4.73, p = 0.01) during follow-up. No deaths occurred among patients with TWA ≥47 μV assigned to ranolazine. In conclusion, in patients with NSTEACS and left ventricular ejection fraction <40%, TWA ≥47 μV early after admission is associated with increased risk of mortality at 1 year and with nonsustained VT during hospitalization. TWA may be useful in risk estimation in patients with NSTEACS. The possibility that TWA may serve as a therapeutic target deserves further exploration.
University of Helsinki and Department of Cardiology, Helsinki University Central Hospital, Helsinki, Finland; Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts; Harvard Medical School, Boston, Massachusetts.
Tuomo
T
Nieminen
Harvard Medical School, Boston, Massachusetts; Thrombolysis in Myocardial Infarction (TIMI) Study Group and Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
Benjamin M
BM
Scirica
Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts; Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
Jose R M
JR
Pegler
Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts; Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
Caio
C
Tavares
Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts; Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
Vitor P F
VP
Pagotto
Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts; Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
Alexandre F
AF
Kanas
Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts; Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil.
Marcel F
MF
Sobrado
Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts; Harvard Medical School, Boston, Massachusetts.
Bruce D
BD
Nearing
Thrombolysis in Myocardial Infarction (TIMI) Study Group and Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
Amarachi A
AA
Umez-Eronini
Harvard Medical School, Boston, Massachusetts; Thrombolysis in Myocardial Infarction (TIMI) Study Group and Cardiovascular Division, Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
David A
DA
Morrow
Gilead Sciences, Foster City, California.
Luiz
L
Belardinelli
Division of Cardiovascular Medicine, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts; Harvard Medical School, Boston, Massachusetts. Electronic address: rverrier@bidmc.harvard.edu.
Richard L
RL
Verrier
D000083:Acetanilides / Q000627:therapeutic use; D054058:Acute Coronary Syndrome / Q000188:drug therapy / Q000401:mortality* / Q000503:physiopathology*; D000368:Aged; D001145:Arrhythmias, Cardiac / Q000188:drug therapy / Q000401:mortality* / Q000503:physiopathology*; D053840:Brugada Syndrome; D000075224:Cardiac Conduction System Disease; D016757:Death, Sudden, Cardiac; D004562:Electrocardiography; D004791:Enzyme Inhibitors / Q000627:therapeutic use; D005260:Female; D006329:Heart Conduction System / Q000002:abnormalities* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000627:therapeutic use; D010919:Placebos; D011237:Predictive Value of Tests; D000069458:Ranolazine; D012307:Risk Factors; D017180:Tachycardia, Ventricular / Q000188:drug therapy / Q000401:mortality* / Q000503:physiopathology*; D016896:Treatment Outcome
D000083:Acetanilides; D004791:Enzyme Inhibitors; D010879:Piperazines; D010919:Placebos; D000069458:Ranolazine