Table 1. IVCT Results of Muscle Biopsies from Six MHS Individuals and Averages for Control Individuals (n = 4)

IVCT =in vitro  caffeine and halothane contracture test. MHS = malignant hyperthermia susceptible; a caffeine threshold concentration at 2.0 mm or less, and  a halothane threshold concentration at 0.44 mm (2.0% v/v) or less; the threshold concentration is the lowest concentration which produces a sustained increase of at least 2 mN (0.2 g) in baseline force. 8