title: Impact of marathon running on cardiac structure and function in recreational runners.
abstract: The present study examined the relationship between LV (left ventricular) function, markers of cardiac-specific damage and markers of oxidative stress in recreational runners following a marathon. Runners (n=52; 43 male and nine female; age, 35+/-10 years; height, 1.74+/-0.08 m; body mass, 75.9+/-8.9 kg) were assessed pre- and immediately post-marathon. LV function was assessed using standard M-mode two-dimensional Doppler echocardiography and TDI (tissue-Doppler imaging) echocardiography. Serum was analysed for cTnT (cardiac troponin-T), TEAC (Trolox equivalent antioxidant capacity; a measure of total antioxidant capacity), MDA (malondealdehyde) and 4-HNE (4-hydroxynonenal). A strong relationship was observed between standard and TDI echocardiography for all functional measures. Diastolic function was altered post-marathon characterized by a reduction in E (peak early diastolic filling: 0.79+/-0.11 compared with 0.64+/-0.16 cm/s; P<0.001), an increase in A (peak late diastolic filling: 0.48+/-0.11 compared with 0.60+/-0.12 cm/s; P<0.001) and a resultant decrease in E/A (ratio of E to A; 1.71+/-0.48 compared with 1.10+/-0.31; P<0.001). Ejection fraction remained unchanged post-marathon. Thirty-two runners presented with cTnT values above the lower limit of detection for the assay (0.01 microg/l), and 20 runners presented post-marathon with cTnT values above the acute myocardial infarction cut-off value (0.05 microg/l). No significant correlations were observed between cTnT and any functional measurements. MDA (2.90+/-1.58 compared with 3.59+/-1.47 micromol/l) and TEAC (1.80+/-0.12 compared with 1.89+/-0.21 mmol/l) were significantly increased post-marathon, but were unrelated to changes in function or cTnT. In conclusion, the present study demonstrated a reduction in diastolic function and widespread evidence of minimal cardiac damage following a marathon in recreational runners. The mechanism(s) underpinning the altered function and appearance of cTnT appear unrelated to reactive oxygen species.
authors.affiliation: Olympic Medical Institute, Northwick Park Hospital, Watford Road, Harrow HA1 3UJ, UK. greg.whyte@eis2win.co.uk
authors.forename: Gregory
authors.initials: G
authors.lastname: Whyte
authors.forename: Keith
authors.initials: K
authors.lastname: George
authors.forename: Robert
authors.initials: R
authors.lastname: Shave
authors.forename: Ellen
authors.initials: E
authors.lastname: Dawson
authors.forename: Claire
authors.initials: C
authors.lastname: Stephenson
authors.forename: Ben
authors.initials: B
authors.lastname: Edwards
authors.forename: David
authors.initials: D
authors.lastname: Gaze
authors.forename: David
authors.initials: D
authors.lastname: Oxborough
authors.forename: Jan
authors.initials: J
authors.lastname: Forster
authors.forename: Rickie
authors.initials: R
authors.lastname: Simspon
mesh_terms: D000293:Adolescent; D000328:Adult; D000447:Aldehydes / Q000097:blood; D000975:Antioxidants / Q000032:analysis; D002839:Chromans / Q000097:blood; D003971:Diastole; D015150:Echocardiography, Doppler; D005260:Female; D006801:Humans; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D008875:Middle Aged; D012420:Running; D020107:Troponin T / Q000097:blood; D016277:Ventricular Function, Left
chemical_list: D000447:Aldehydes; D000975:Antioxidants; D002839:Chromans; D020107:Troponin T; D008315:Malondialdehyde; C027576:4-hydroxy-2-nonenal; C010643:6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid