To study preliminary severe prognostic risk factors related to mortality immediately during the first 24 hours of Percutaneous Coronary Intervention (PCI). Object and research methodology: from 08/2008 to 02/2009, 511 patients underwent PCI at the Vietnam Heart Institute. Some severe risk factors involving death prognostic during the first 24 hours were used for analysis. Results: Mortality rate during the first 24 hours of procedures constituted 2,2 percent, mortality rate in female is 2,6 percent and 2 percent in male, the average age of patients death was 68,91 + or - 10,23. Mortality of urgent procedures was higher than mortality of elective procedures (3,7 percent 0,4 percent) with P 0,05. Some severe prognostic risk factors involving: cardiogenic shock (p 0,001), heart failure Killip level III (p 0,05), heart failure NYHA level III-IV (p 0,001), left ventricular ejection fraction 29 percent (p 0,001), renal disease (p 0,05), left main disease (p 0,01), triple vessel disease (p 0,001).