ICDs are primarily life saving devices.Whether single or dual chamber it does this function effectively.They will also take care of bradycardia by default back up pacing .For most indications single chamber ICDs are good enough.
My professor used to tell us , dual lead means , dual expertise , dual cost , dual caution and dual set of complication . One should avoid it whenever possible. Make things as simple as it could be , without compromising the main goal (Here prevention of SCD) . The incidence of inappropriate shocks being lesser with dual chamber ICD has not been truly realised in real world scenario.
Recent studies tend to give credence to this perception .(Peterson JAMA 2013)
Dual Chamber ICDs may have an edge only in few situations .
- When there are both indication for pacing as well as ICD like heart block and LV dysfunction.
- In extreme LV dysfunction were benefits of dual chamber pacing may have advantage.(If CRT is not an option )
Reference.
Dr.S.Venkatesan MD 