Fig. 1. Rapid cardiac performance deterioration after CM-specific Lmna deletion.

(A) Tam dosing schedule. Red arrows denote days of Tam injection and blue arrows show 2 days of rest. “12w old” denotes 12-week-old mice. (B) Hearts excised from CM-CreTRAP:Lmna^flox/flox mice treated with vehicle (Veh) or Tam for 2 and 4 weeks. (C) Echo on CM-CreTRAP:Lmna^flox/+ (diamond) and CM-CreTRAP:Lmna^flox/flox (circle) at 2 and 4 weeks Tam treatment. *P = 0.015 and **P < 0.0001 using one-way analysis of variance (ANOVA), followed by Dunnett’s multiple comparison correction with the Veh group serving as comparison control. Error bars = SEM. Blue = male and red = female mice. (D) Tabulation of echo data ± SEM. FS, fractional shortening; EF, ejection fraction; LVESD, left ventricular end systolic dimension; LVEDD, left ventricular end diastolic dimension; LVESPW, left ventricular end systolic posterior wall; LVEDPW, left ventricular end diastolic posterior wall. Veh-treated mice at 2 and 4 weeks were measured together with the Tam-treated group but pooled and presented as a single Veh control group because no differences were noted between them.