Figure 1.

Electrophysiological abnormalities in very long-chain acyl-CoA dehydrogenase deficiency (VLCADD) human induced pluripotent stem cell- cardiomyocytes (hiPSC-CMs). (A) Increased C14/C2 carnitine and C16/C2 carnitine ratio in medium of iVLCADD1-CMs and iVLCADD2-CMs compared to control cardiomyocytes (iCTRL-CM) after 96 h culturing with palmitate loading. Data expressed as mean + SD (n = 3). Statistical analysis was performed using a two-way ANOVA with Sidaks multiple comparisons test. * = p < 0.05. (B) Analyzed action potential (AP) parameters. (C) Representative APs paced at 1 Hz. (D) Average AP parameters. (E) Typical delayed afterdepolarizations (DADs) measured during an 8 s pause after fast pacing (3 Hz). After this pause, a single AP was evoked to confirm that no early afterdepolarizations occurred. (F) Average number of DADs. Electrophysiology data are expressed as mean+SEM of individual measured cells (n = 11–13). (G) Analyzed parameters in Ca²⁺ transients. (H) Representative Ca²⁺ transients of Indo-1 loaded hiPSC-CMs paced at 1 Hz. (I) Average [Ca²⁺]i (mean+SEM) * = p < 0.05. Statistical analysis was assessed with one-way ANOVA with Tukey’s multiple comparisons test.