The international medical team treating Venezuela ’s cancer-ridden leader Hugo Chávez believe that, absent a radical change in his condition, he is not likely to survive more than six months. According to sources that have provided me privileged information and documents from within the Venezuelan regime for many months, recent tests show that Chávez’s cancer is accelerating and his chances of surviving until the October 2012 presidential elections are worsening.

This sobering prognosis is a dilemma for Caracas, where Chavista leaders are afraid that their fiercest followers will feel betrayed when they learn his claim to be “cancer-free” turns out to be a big lie. Meanwhile, Washington policy makers appear unprepared to deal with the chaos that will ensue as the most corrupt members of the Chávez regime plot to retain power at all costs and as the state-run economy collapses.

Chávez wants his people to believe that he was “cured” months ago and that recent visits to Cuba have been to confirm his miraculous recovery. In fact, his physical deterioration is advancing faster than doctors had expected.

Despite this grave situation, Chávez has insisted on receiving only light doses of chemotherapy to avoid long absences from the political stage during this precarious period. Under his desperate plan, Chávez’s team will announce “short vacations” and “rest breaks,” during which he really will be receiving treatment at a specialized medical facility that has been installed recently at the presidential retreat on the island of La Orchila.

These latest revelations are consistent with months of reporting from inside sources. What began as an aggressive prostate cancer more than a year ago had spread to his lymphatic system, colon and bones even before Chávez agreed to seek treatment.

His body’s reaction to the first two rounds of chemo was so debilitating that he only received the third round during his most recent visit to Cuba. (On the two prior occasions when he was to undergo treatment, his medical team decided that his red cell count was too low and his condition so weak that chemotherapy would do more harm than good.)

Doctors believe that Chávez’s fateful decision to demand weaker doses of chemo so he can try to continue his public duties to be suicidal, but they have no choice but to go along with this desperate scheme. To make matters worse, the very painful radiological treatment of cancerous cells in his bones has yet to begin.

Chávez’s second dangerous decision has been to continue to deceive the Venezuelan people about his grave condition. His political advisors are worried that, in addition to hastening his own death, he will be leaving his successor with the impossible task of explaining why Chavista leaders deliberately deceived party loyalists. They believe that Chávez’s willful dishonesty will shatter the bond with his base and undermine their desperate bid to hold on to power just as they face an invigorated, unified opposition.

Chávez and his insiders, who have had months of advance-notice of the impending crisis, have concluded that foreign minister Nicolas Maduro has the best chance of appealing to their base as a substitute presidential candidate. Meanwhile, notorious Venezuelan narco-generals are determined to preserve their safe-haven even if it means scuttling elections.

U.S. diplomats have consciously averted attention from Venezuela for years to avoid having to confront the growing threat posed by a decade of Chávez’s conspiring with our enemies and rivals. According to sources, U.S. officials knew of Chávez’s cancer six months before his public admission, and they now know that he is not expected to stand for election next October.

A U.S. inter-agency task force is required to plan for the chaos that might ensue as Chavez loyalists and democratic leaders jockey for power. Diplomats must move quietly but quickly to coordinate a regional response to Chávez’s death that will press for a genuine democratic transition, and not the succession Chavistas have in mind.

After Chávez exits the stage, regional leaders should be mobilized to insist that the regime and its foreign backers respect the results free, fair, and internationally monitored elections in October. The inter-American community should pledge to assist the rehabilitation of the economy and the restoration of the rule of law.

There are some crucial issues where only leadership from Washington will suffice. For example, Venezuelan narco-generals must be isolated so they cannot thwart a peaceful transition, and those military officers loyal to the constitution must be bolstered. Havana, Beijing, Moscow, and Teheran must be put on notice to step aside as Venezuelans reclaim their future. And, U.S. planners must be prepared to deal with the short-term impact of unrest in a country where we import about 10 percent of our oil.

Washington also must develop a long-term plan to help Venezuelans clean up the toxic waste of terrorists, narcotraffickers, corruption, and Cuban agents that Chávez will leave behind.

Roger F. Noriega was Ambassador to the Organization of American States from 2001-03 and Assistant Secretary of State from 2003-05. He is a visiting fellow at the American Enterprise Institute and managing director of Vision Americas LLC, which represents U.S. and foreign clients, and he contributes to www.interamericansecuritywatch.com.