Cardiac Arrest: Prevention

To prevent cardiac arrest/sudden cardiac death, attention must be paid to reducing individual risk factors. Behavioral risk factors

  • Diet
    • Ingredients of energy drinks (prolongations of the QTc interval) ?
    • Micronutrient deficiency (vital substances).
      • Low potassium
      • Low magnesium
  • Stimulant consumption
    • Alcohol excesses at the weekend → accumulation of sudden deaths on Monday.
    • Tobacco (smoking)* – men with sudden cardiac death were about 60% more likely to be smokers
  • Drug use
    • Cocaine
  • Physical activity
    • Ambitious recreational athletes (average age: 47 years; for soccer and running); extremely rare professional competitive athletes.
    • Triathlon (fatal incidents: 1.47/100,000; marathons: 1.00/100,000):
      • Age
        • > 40 years: 6.08/100,000; up to 50 years: 9.61/100,000
        • 60 years and older 18.61/100,000)
      • Deaths and cardiac arrests occurred in.
        • 67% of those during swimming
        • 16% during cycling
        • 11 % while running
        • 6 % during the recovery phase after the competition

      In one study, evidence of myocardial fibrosis (muscle tissue of the heart is replaced by connective tissue) was found in nearly one in five male triathletes in a cardiac magnetic resonance imaging scan; in the long term, this results in ischemic cardiomyopathy (heart muscle disease that causes the heart and heart muscle to lack an adequate supply of blood and nutrients) and heart failure (cardiac insufficiency).

  • Psycho-social situation
    • Pessimism
  • Overweight (BMI ≥ 25; obesity)* .

Disease-related risk factors

  • Diabetes mellitus type 2 *
  • Hypercholesterolemia *
  • Hypertension*

* Most common risk factors of sudden cardiac death; men and women who had none of these risk factors had a very low risk of sudden cardiac death. Additional notes

  • To prevent sudden cardiac death, attention must be paid to typical cardiovascular risk factors, such as smoking, obesity, diabetes, hypertension, and hypercholesterolemia.In one study, the ECG before the event showed abnormal findings in almost all affected individuals (78%). The most common ECG findings were sinus tachycardia (39%), negative T wave (30%), and prolonged QT interval (26%).
  • In young competitive athletes, genetic disease such as hypertrophic obstructive cardiomyopathy (HOCM), arrhythmogenic right ventricular cardiomyopathy (ARVC), or ion channel disease should be excluded early.
  • Tight wetsuit (→ cardiac arrest during diving); attempt at explanation: possibly the wetsuit tightly fitting the patient’s neck led to irritation of the baroreceptors located in the carotid sinus during immersion in the water (carotid sinus syndrome: see below “Cardiac arrest/Pathogenesis – Etiology/Cardiovascular system“).
  • An ECG phenomenon may allow detection of high-risk patients. Scientists have shown that the repolarization (excitation regression) of the heart (T wave in the ECG) is subject to low-frequency modulations. They refer to the newly identified oscillations, which occur every 10 seconds to minutes, as Periodic Repolarization Dynamics (PRD).This procedure may in the future make a decisive contribution to the early detection of high-risk patients and preventive treatment, for example, by implanting a defibrillator (ICD, implantable cardioverter defibrillator).

Prevention factors (protective factors)

  • Omega-3 fatty acids – Regular consumption of fish (non-fried fish once or twice a week) may reduce the risk of sudden cardiac death.
    • Prefer: anchovies, herring, salmon, mackerel, sardines, tuna.
  • Moderate physical activity
    • 150 to 750 minutes of exercise per week, consuming an average of four metabolic equivalents (MET) (≡ exertion while doing light housework or climbing stairs slowly) → a 20 percent reduced mortality risk (risk of death) (hazard ratio 0.80; 0.74-0.87) compared with people who exercised less
    • Active 750 minutes per week or more with four MET → 35 percent reduced mortality risk (hazard ratio 0.65; 0.60-0.71)
  • Implantable cardioverter defibrillator (ICD) for prevention of sudden cardiac death (secondary prevention, if applicable).
  • Defibrillator vest for temporary protection against sudden cardiac death; insb. in the early phase of cardiomyopathies (heart muscle diseases) during the optimization of a heart failure therapy (therapy of a heart failure) indicated.