biostudies-literatureMaruyama MNHLBI NIH HHS399-408https://www.ebi.ac.uk/biostudies/studies/S-EPMC2818796biostudies-literatureUnknown106(2)<h4>Rationale</h4>Recurrent ventricular arrhythmias after initial successful defibrillation are associated with poor clinical outcome.<h4>Objective</h4>We tested the hypothesis that postshock arrhythmias occur because of spontaneous sarcoplasmic reticulum Ca release, delayed afterdepolarization (DAD), and triggered activity (TA) from tissues with high sensitivity of resting membrane voltage (V(m)) to elevated intracellular calcium (Ca(i)) (high diastolic Ca(i)-voltage coupling gains).<h4>Methods and results</h4>We simultaneously mapped Ca(i) and V(m) on epicardial (n=14) or endocardial (n=14) surfaces of Langendorff-perfused rabbit ventricles. Spontaneous Ca(i) elevation (SCaE) was noted after defibrillation in 32% of ventricular tachycardia/ventricular fibrillation at baseline and in 81% Circulation researchDiastolic intracellular calcium-membrane voltage coupling gain and postshock arrhythmias: role of purkinje fibers and triggered activity.PMC2818796R01 HL071140-06R01 HL071140-03R01 HL071140-04R01 HL071140-01R01 HL078932R01 HL071140-02R01 HL071140-05A1P01 HL78931R01 HL071140P01 HL078931-020003R01 HL78932R01 HL078932-02R01 HL078932-01R01 HL71140R01 HL078932-04R01 HL078932-03P01 HL078931-050003P01 HL078931P01 HL078931-040003R01 HL071140-07S1R01 HL071140-06S1R01 HL078932-05A1P01 HL078931-030003R01 HL071140-07P01 HL078931-01A10003Joung BKim DHShen MJChoi EKTang LShinohara TMaruyama MOn YKWeiss JNLin SFHan SChen PSfalseDiastolic intracellular calcium-membrane voltage coupling gain and postshock arrhythmias: role of purkinje fibers and triggered activity.<h4>Rationale</h4>Recurrent ventricular arrhythmias after initial successful defibrillation are associated with poor clinical outcome.<h4>Objective</h4>We tested the hypothesis that postshock arrhythmias occur because of spontaneous sarcoplasmic reticulum Ca release, delayed afterdepolarization (DAD), and triggered activity (TA) from tissues with high sensitivity of resting membrane voltage (V(m)) to elevated intracellular calcium (Ca(i)) (high diastolic Ca(i)-voltage coupling gains).<h4>Methods and results</h4>We simultaneously mapped Ca(i) and V(m) on epicardial (n=14) or endocardial (n=14) surfaces of Langendorff-perfused rabbit ventricles. Spontaneous Ca(i) elevation (SCaE) was noted after defibrillation in 32% of ventricular tachycardia/ventricular fibrillation at baseline and in 81% 2010-01-01T00:00:00Z2010 Feb2025-05-31T23:56:52.139Z2025-05-31T23:56:52.139ZS-EPMC28187961992687110.1161/circresaha.109.21129210.1161/CIRCRESAHA.109.211292