Stockholders' Equity - Additional Information (Detail) - $ / shares	1 Months Ended	6 Months Ended
	Oct. 18, 2012	Sep. 30, 2015	Mar. 31, 2015	Jul. 21, 2014	Apr. 29, 2013
Stockholders Equity Note [Line Items]
Equity incentive plan, shares available for future grant		90,000
Common Stock, shares authorized		100,000,000	100,000,000
Expected dividend rate		0.00%
Class of Warrant or Right, Number of Securities Called by Warrants or Rights				100,000
Price Per Share Level For Future Issuance Of Common Shares		$ 9.00
Note warrant
Stockholders Equity Note [Line Items]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		300,000
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 10.00
Placement agent warrants
Stockholders Equity Note [Line Items]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights		200,000
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 20.00
9% Notes Payable
Stockholders Equity Note [Line Items]
Convertible notes, interest rate		9.00%
Southern California Heart Centers [Member]
Stockholders Equity Note [Line Items]
Class of Warrant or Right, Exercise Price of Warrants or Rights				$ 10.00
2010 Equity Incentive Plan
Stockholders Equity Note [Line Items]
Equity incentive plan, additional shares authorized for issuance	9,000,000
Issuance of common stock for services (shares)		1,200,000
2013 Equity Incentive Plan
Stockholders Equity Note [Line Items]
Equity incentive plan, shares authorized for issuance					500,000
Equity incentive plan, shares available for future grant		90,000