Kahane was already forced to cancel last month's concerts due to hypertension; his condition has not worsened but his doctor reportedly wants him to have additional time to recuperate.
Kahane is now scheduled to return to the podium on May 25, and is still planning to serve as both pianist and conductor during a major Beethoven festival in early June, where he will play all the composer's concertos.
The April 13-14 concerts in Boettcher Hall that Kahane was scheduled to conduct will instead be led by associate conductor Scott O'Neil. The program, featuring Ravel's Piano Concerto for the Left Hand, the CSO premiere of Bright Sheng's Tibetan Swing and Rachmaninoff's Piano Concerto No. 2 with pianist Christopher O'Riley, remains unchanged. O'Neil and pianist Jeffrey Lee will then join O'Riley in the originally scheduled multi-keyboard family program on April 15.
Nicholas Carthy, a faculty member at the University of Colorado and music director of the school's opera program, will conduct the April 20-21 concerts, featuring violinist Lindsay Deutsch, tenor Thomas Glenn and CSO principal horn Michael Thornton.
Symptoms of severe hypertension can include confusion, headaches and vision irregularities. The Post quoted cardiologist Darren Mitchell as saying that it wasn't surprising that Kahane canceled all his performances, as even modest activity can elevate blood pressure and complicate treatment.