Male Wistar rats (6-7 weeks old) with chronic heart failure (CHF), Iberiotoxin (0.125 nmol/nl, 1.25 nmol/nl and 12.5 nmol/nl) is infused into paraventricular hypothalamic nucleus (PVN) by osmotic minipumps. After perfusion of Iberiotoxin by microinjection of rAAV2-KCNMB4 shRNA virus, right ventricular weight/body weight and lung weight/body weight ratio as well as left ventricular end-diastolic diameter are increased and left ventricular ejection fraction is decreased.