TY - JOUR
T1 - Electrocardiographic changes during sustained normobaric hypoxia in patients after myocardial infarction
AU - Kramer, Tilmann
AU - Hoenemann, Jan Niklas
AU - Weis, Henning
AU - Hoffmann, Fabian
AU - Rosenkranz, Stephan
AU - Baldus, Stephan
AU - Hellmich, Martin
AU - Levine, Benjamin D.
AU - Jordan, Jens
AU - Tank, Jens
AU - Limper, Ulrich
N1 - Publisher Copyright:
© 2023, Springer Nature Limited.
PY - 2023/12
Y1 - 2023/12
N2 - The safety of prolonged high-altitude stays and exercise for physically fit post-myocardial infarction (MI) patients is unclear. Myocardial tissue hypoxia and pulmonary hypertension can affect cardiac function and electrophysiology, possibly contributing to arrhythmias. We included four non-professional male athletes, clinically stable after left ventricular MI (three with ST-segment elevation MI and one with non-ST-segment elevation MI) treated with drug-eluting stents for single-vessel coronary artery disease. Oxygen levels were reduced to a minimum of 11.8%, then restored to 20.9%. We conducted electrocardiography (ECG), ergometry, and echocardiography assessments in normoxic and hypoxic conditions. With an average age of 57.8 ± 3.3 years and MI history 37 to 104 months prior, participants experienced a significant increase in QTc intervals during hypoxia using Bazett’s (from 402 ± 13 to 417 ± 25 ms), Fridericia’s (from 409 ± 12 to 419 ± 19 ms), and Holzmann's formulas (from 103 ± 4 to 107 ± 6%) compared to normoxia. This effect partially reversed during recovery. Echocardiographic signs of pulmonary hypertension during normobaric hypoxia correlated significantly with altered QTc intervals (p < 0.001). Despite good health and complete revascularization following MI, susceptibility to hypoxia-induced QTc prolongation and ventricular ectopic beats persists, especially during physical activity. MI survivors planning high-altitude activities should consult cardiovascular specialists with high-altitude medicine expertise.
AB - The safety of prolonged high-altitude stays and exercise for physically fit post-myocardial infarction (MI) patients is unclear. Myocardial tissue hypoxia and pulmonary hypertension can affect cardiac function and electrophysiology, possibly contributing to arrhythmias. We included four non-professional male athletes, clinically stable after left ventricular MI (three with ST-segment elevation MI and one with non-ST-segment elevation MI) treated with drug-eluting stents for single-vessel coronary artery disease. Oxygen levels were reduced to a minimum of 11.8%, then restored to 20.9%. We conducted electrocardiography (ECG), ergometry, and echocardiography assessments in normoxic and hypoxic conditions. With an average age of 57.8 ± 3.3 years and MI history 37 to 104 months prior, participants experienced a significant increase in QTc intervals during hypoxia using Bazett’s (from 402 ± 13 to 417 ± 25 ms), Fridericia’s (from 409 ± 12 to 419 ± 19 ms), and Holzmann's formulas (from 103 ± 4 to 107 ± 6%) compared to normoxia. This effect partially reversed during recovery. Echocardiographic signs of pulmonary hypertension during normobaric hypoxia correlated significantly with altered QTc intervals (p < 0.001). Despite good health and complete revascularization following MI, susceptibility to hypoxia-induced QTc prolongation and ventricular ectopic beats persists, especially during physical activity. MI survivors planning high-altitude activities should consult cardiovascular specialists with high-altitude medicine expertise.
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U2 - 10.1038/s41598-023-43707-5
DO - 10.1038/s41598-023-43707-5
M3 - Article
C2 - 37838799
AN - SCOPUS:85174237638
SN - 2045-2322
VL - 13
JO - Scientific reports
JF - Scientific reports
IS - 1
M1 - 17452
ER -