Cardiac arrest at rest and during sport activity: causes and prevention

Abstract

In the Western Countries, cardiovascular diseases are still the most frequent cause of death, which is often sudden. Sudden death (SD) in the young population occurs at a rate of 1/100 000/year and carries a profound social impact both for the young age of the victims and the unanticipated occurrence. Physical effort is a triggering risk factor, in fact SD occurs three times more frequently in athletes than in non-athletes. The screening for sport activity fitness can identify apparently healthy subjects carrying a silent abnormality able to trigger sudden cardiac death during sport activity, thus the fitness screening could be lifesaving. The spectrum of cardiovascular conditions identified at post-mortem examination is quite extensive, and include: coronary, myocardial, valvular diseases, as well as conduction system abnormalities. In 20% of the cases, the heart is normal, and sudden cardiac death is ascribed to ionic channel disease. The diagnosis of cardiomyopathy is possible with the integration of electrocardiogram and echography, thus decreasing significantly the occurrence of SD of athletes in Italy, but early diagnosis of coronary artery disease still remains challenging. The best strategy to further decrease sudden cardiac death during sport activities consists in combining early diagnosis with widespread availability of defibrillators on site.

Keywords: Autopsy; Screening; Sudden cardiac death.

Figure 1

Coronary artery disease causing sudden death under stress in the athlete (negative competitive fitness test). (A) Coronary atherosclerosis of the first section of the anterior descending branch. (B) Normal effort ECG trace (same patient in A). (C) Anomalous origin of the right from the left coronary sinus of Valsalva; (D) normal effort ECG trace (same patient in C).

Figure 2

Arrhythmogenic cardiomyopathy of the right ventricle vs. left form. While the identification of the classical variant (A, B) with transmural fibroadipose substitution and aneurysms, with typical ECG alterations, is today possible at screening for agonistic suitability. The identification of the left forms (C, D) with subepicardial fibroadiposis, without thinning and aneurysms, and often normal ECG remains difficult.