TY - JOUR
T1 - Impact of Myocardial Salvage Assessed by 99mTc-Sestamibi Scintigraphy on Cardiac Autonomic Function in Patients Undergoing Mechanical Reperfusion Therapy for Acute Myocardial Infarction
AU - Bauer, Axel
AU - Mehilli, Julinda
AU - Barthel, Petra
AU - Müller, Alexander
AU - Kastrati, Adnan
AU - Ulm, Kurt
AU - Schömig, Albert
AU - Malik, Marek
AU - Schmidt, Georg
N1 - Funding Information:
Dr. Schmidt holds patents on Heart Rate Turbulence and Deceleration Capacity, and has received grants from the Bundesministerium für Bildung, Wissenschaft, Forschung und Technologie (13N/7073/7), the Kommission für Klinische Forschung, and the Deutsche Forschungsgemeinschaft (SFB 386).
PY - 2009/4
Y1 - 2009/4
N2 - Objectives: The purpose of this study was to analyze the impact of myocardial salvage on cardiac autonomic function in patients undergoing mechanical reperfusion therapy for acute myocardial infarction (MI). Background: Heart rate deceleration capacity (DC) and heart rate turbulence slope (TS) are strong predictors of post-MI mortality. Salvage of jeopardized myocardium is the main mechanism by which patients benefit from reperfusion therapy. The impact of myocardial salvage on DC and TS is unknown. Methods: The study enrolled 854 consecutive patients undergoing mechanical reperfusion therapy for first MI. Paired 99mTc-sestamibi scintigraphy studies (acute and 7 to 14 days after reperfusion) were used to calculate myocardial salvage index. DC and TS were assessed from Holter recordings 7 to 14 days after reperfusion. Patients were categorized into 3 groups by salvage index: <30% (n = 244), 30% to 60% (n = 257), and ≥60% (n = 353). Results: In the 3 groups, DC was 5.2 (interquartile range 3.5 to 7.1) ms, 5.7 (4.1 to 7.3) ms, and 6.4 (5.0 to 8.0) ms, whereas TS was 5.3 (2.6 to 8.4) ms/R-R interval, 6.9 (3.2 to 11.7) ms/R-R interval, and 7.8 (4.1 to 13.2) ms/R-R interval, respectively (p < 0.0001 for both). After adjustment for left ventricular ejection fraction (LVEF), initial perfusion defect, creatine kinase, age, diabetes mellitus, sex, and medical therapy, patients with salvage index <30% had a 2.6-fold risk (95% confidence interval: 1.8 to 3.9, p < 0.001) of having abnormal DC (≤4.5 ms) or TS (≤2.5 ms/R-R interval) compared with patients with salvage index ≥60%. However, patients who had autonomic dysfunction defined by abnormal DC and TS had a poor prognosis independent of whether or not the salvage index was <30% (5-year mortality rates of 16.5% and 17.3%, respectively). In contrast, prognosis was excellent when both factors were normal (5-year mortality rates of 2.9% and 4.0%, respectively). Predictive value of impaired LVEF (≤40%) was also independent of salvage index. Multivariably, both autonomic dysfunction and impaired LVEF were independent predictors of 5-year mortality. Conclusions: In patients undergoing mechanical reperfusion therapy for acute MI, salvage index is an independent predictor of autonomic dysfunction but does not affect its prognostic value.
AB - Objectives: The purpose of this study was to analyze the impact of myocardial salvage on cardiac autonomic function in patients undergoing mechanical reperfusion therapy for acute myocardial infarction (MI). Background: Heart rate deceleration capacity (DC) and heart rate turbulence slope (TS) are strong predictors of post-MI mortality. Salvage of jeopardized myocardium is the main mechanism by which patients benefit from reperfusion therapy. The impact of myocardial salvage on DC and TS is unknown. Methods: The study enrolled 854 consecutive patients undergoing mechanical reperfusion therapy for first MI. Paired 99mTc-sestamibi scintigraphy studies (acute and 7 to 14 days after reperfusion) were used to calculate myocardial salvage index. DC and TS were assessed from Holter recordings 7 to 14 days after reperfusion. Patients were categorized into 3 groups by salvage index: <30% (n = 244), 30% to 60% (n = 257), and ≥60% (n = 353). Results: In the 3 groups, DC was 5.2 (interquartile range 3.5 to 7.1) ms, 5.7 (4.1 to 7.3) ms, and 6.4 (5.0 to 8.0) ms, whereas TS was 5.3 (2.6 to 8.4) ms/R-R interval, 6.9 (3.2 to 11.7) ms/R-R interval, and 7.8 (4.1 to 13.2) ms/R-R interval, respectively (p < 0.0001 for both). After adjustment for left ventricular ejection fraction (LVEF), initial perfusion defect, creatine kinase, age, diabetes mellitus, sex, and medical therapy, patients with salvage index <30% had a 2.6-fold risk (95% confidence interval: 1.8 to 3.9, p < 0.001) of having abnormal DC (≤4.5 ms) or TS (≤2.5 ms/R-R interval) compared with patients with salvage index ≥60%. However, patients who had autonomic dysfunction defined by abnormal DC and TS had a poor prognosis independent of whether or not the salvage index was <30% (5-year mortality rates of 16.5% and 17.3%, respectively). In contrast, prognosis was excellent when both factors were normal (5-year mortality rates of 2.9% and 4.0%, respectively). Predictive value of impaired LVEF (≤40%) was also independent of salvage index. Multivariably, both autonomic dysfunction and impaired LVEF were independent predictors of 5-year mortality. Conclusions: In patients undergoing mechanical reperfusion therapy for acute MI, salvage index is an independent predictor of autonomic dysfunction but does not affect its prognostic value.
KW - autonomic function
KW - myocardial infarction
KW - myocardial salvage
KW - reperfusion
UR - http://www.scopus.com/inward/record.url?scp=64149123173&partnerID=8YFLogxK
U2 - 10.1016/j.jcmg.2008.12.018
DO - 10.1016/j.jcmg.2008.12.018
M3 - Article
C2 - 19580728
AN - SCOPUS:64149123173
SN - 1936-878X
VL - 2
SP - 449
EP - 457
JO - JACC: Cardiovascular Imaging
JF - JACC: Cardiovascular Imaging
IS - 4
ER -