The main aim of cardiac screening in athletes is to reduce the prevalence of sudden cardiac death. Electrocardiography (ECG) is a diagnostic tool to detect athletes at increased risk, but “abnormal” ECG findings related to training are common in athletes, and a challenge to distinguish from pathological ECG findings. Blood pressure (BP) is recorded during screening examinations, and high BP accounts for the highest prevalence of abnormal findings. This has neither been emphasized as an isolated finding, nor in association to other cardiovascular risk factors.
In 2008, 595 professional soccer players in Norway underwent cardiac screening. By applying the new Seattle criteria for abnormality, the prevalence of abnormal ECGs was reduced to 11%. Abnormal ECG findings were more common after computer-based vs visual measurements both according to the ESC recommendations (51% vs 29%), and the Seattle criteria (22% vs 11%). Every fourth player had high normal BP, and there was a significant association between increasing BP, and subclinical organ damages. High daytime ambulatory BP was estimated in every third player and high nighttime ambulatory BP in every second player. Echocardiography alone did not detect important abnormality. All players, except two with hypertension and left ventricular hypertrophy, got medical clearance.
The Seattle criteria for interpreting ECG in athletes reduced the need for follow-up investigations, and based on echocardiographic evaluations this reduction increased the specificity of the Seattle criteria, without increasing the number of false negative ECGs. We experienced several difficulties when trying to decide the prevalence of abnormal ECGs in athletes, and revealed a need for new definitions of “standard” methodology. The novel findings of masked hypertension and high nighttime BP are surprising, and the associations between BP and hypertensive subclinical organ damages emphasize the need for closer focus on BP measurements.
This thesis is based on the following original research papers (papers I., II. & IV. are removed due to publisher copyright restrictions):
I. Berge HM, Gjerdalen GF, Andersen TE, Solberg EE, Steine K. Blood pressure in professional male football players in Norway. J Hypertens 2013;31:672-679. doi:10.1097/HJH.0b013e32835eb5fe.
II. Berge HM, Andersen TE, Solberg EE, Steine K. High ambulatory blood pressure in male professional football players. Br J Sports Med 2013;47:521-525. doi:10.1136/bjsports-2013-092354
III. Berge HM, Gjesdal K, Andersen TE, Solberg EE, Steine K. Prevalence of abnormal ECGs in male soccer players is still high, but decreases with the Seattle criteria. Submitted to Scand J Med Sci Sports. Article first version [24 June 2014] doi:10.1111/sms.12274
IV. Berge HM, Steine K, Andersen TE, Solberg EE, Gjesdal K. Visual or computer-based measurements: Important for interpretation of athletes’ ECG. Br J Sports Med Published Online First: [22 February 2014] doi:10.1136/bjsports-2014-093412