Diagnosis and management of out-of-hospital cardiac arrest secondary to coronary artery spasm.

OBJECTIVE: The clinical features of coronary artery spasm as a cause of cardiac arrest were determined in a prospective study on out-of-hospital cardiac arrest (OHCA).
METHODS: Coronary angiography was performed at admission in 300 consecutive patients with no obvious non-cardiac cause of OHCA. In survivors with no or minimal coronary artery stenosis, a second angiography with provocation test and electrophysiological testing were performed at 1 month.
RESULTS: Spasm was demonstrated in ten patients. Diagnosis was based upon (1) spontaneous spasm on the admission angiogram (3 patients), (2) transient significative ST-segment elevation at follow-up in patients with no or non-significant coronary artery lesions (4 patients) and (3) spasm during the 1 month provocation test (3 patients). Six patients survived at 1 month; spasm occurred during a new provocation test in five despite treatment with high dosage calcium channel blockers leading to coronary stenting in two, an internal cardiovertor defibrillator in one, and increased drug therapy with prolonged hospitalization in the remainder. At a mean follow-up of 55+/-27 months, no recurrent cardiac arrest occurred.
CONCLUSION: Systematic coronary angiograms and provocation tests in survivors of OHCA allow prompt diagnosis of coronary artery spasm. Residual spasm despite treatment with calcium channel blockers is frequent. Therapy should therefore be guided by repetitive provocation tests, and seems to avoid recurrence of cardiac arrest.