• Patients resuscitated from sudden cardiac arrest having normal ECG, echo and coronary angiogram.
  • Further evaluated by cardiac MRI, SAECG, exercise testing and provocative drug testing with adrenaline and procainamide. Selected patients underwent EP study and genetic studies.
  • Out of 68 patients who were evaluated, in 35 cases (56%) a cause could be found out.
  • The commonest cause found was LQTS.
  • Other causes in descending order – CPVT, ARVC, early repolarization, coronary spasm, Brugada syndrome and myocarditis.
  • The test with maximum yield was provocative drug testing. This led to diagnoses of LQTS, CPVT or ARVC.
  • Thus further evaluation by these tests can identify the cause of sudden cardiac arrest in around half of cases with normal ECG, echo and CAG.
  • Circulation 2009;120:278-285.