Argentine singer SERGIO DENIS is seriously ill in a Paraguayan hospital after suffering heart failure. The veteran star was taken to hospital in the capital Asuncion after collapsing in his hotel in the city at the weekend - ahead of a concert scheduled there for tonight (21May07). Doctor Hugo Gomez Fernandez, at the San Roque Hospital, says, "He suffered an apparently very delicate failure in the hotel where he was staying, and while being taken to the hospital, his heart stopped, and he arrived in that state at the emergency room, showing no signs of life, where they gave him CPR to revive him.” Denis was then taken to the intensive therapy unit where he underwent exploratory surgery. Cardiologist Gustavo Olmedo says, “We suspected a heart attack, but we ruled that out after a cardiac catheterization, at which point we also did a pulmonary study, which allowed us to rule out a pulmonary embolism. “We concentrated on the abdominal region again and confirmed that there was bleeding, apparently in the abdomen. We still don’t have a clear cause and the patient will undergo surgery. “The abdomen will be explored because it has been determined that his level of haemoglobin is falling and the scan detected blood in the abdomen, that’s why we’re doing the surgery. During the procedure we’ll determine the source of the bleeding." Doctors reveal that the singer is now breathing with the aid of a machine and is being given medication to increase his blood pressure.