May 25-26, 1922 – Lenin’s first stroke…
Was Stalin attempting to assassinate him, or delayed impact of Fanya Kaplan’s curare-laden bullet? http://nyti.ms/1KevvPB
Excerpt from Revolution from Within:
Lenin’s urgency that year  may be attributed to many causes, several of which reinforce why he found it necessary to expel these intellectuals and not stir international censure by applying a more direct, final solution:
First, thanks to the Rapallo treaty with Germany, the Bolsheviks were finally able to borrow from international banks and were heavily involved in loan negotiations. International censure of their government could interrupt such efforts or result in more unfavorable interest rates.
Second, the Bolsheviks needed to take advantage of strict deadlines set in the ARA relief and could not risk any action that could be used as an excuse to cancel the program ahead of time. Hoover had already threatened to stop ARA relief measures when just the VKPG leaders were sentenced to death; if Lenin had 160 of the most renowned intellectuals killed—including many members of the VKPG—he could well expect the ARA to withdraw its support.
Another cause for urgency may have been more personal to Lenin: his determination to see a removal of his lifelong adversaries from Russia before he died. When Lenin plotted their demise, he was still in Gorki recovering from the first of three strokes. Medical experts assessing his symptoms noted the calcification of his arteries: “When tapped with tweezers they sounded like stone.”
Lenin did not smoke and he drank only occasionally. He exercised regularly. Medically interesting were the seizures he experienced right before he died—unusual for stroke victims, but common in cases of toxic exposure. Some doctors hypothesize he was poisoned over many years through the use of arsenic or potassium cyanide, like Rasputin. Of course, Fanya Kaplan also shot Lenin in 1918 in an attempted assassination: “One bullet lodged in his collarbone after puncturing his lung. Another got caught in the base of his neck. Both bullets remained in place for the rest of his life.” The bullets apparently were poisoned by curare. Clearly, he was a sick man facing his own mortality.
 Gina Kolata, “Lenin’s Stroke: Doctor has a Theory (and a Suspect),” The New York Times, May 7, 2012. “In 1921 Lenin started complaining that he was ill. From then until his death in 1924, Lenin “began to feel worse and worse,” Dr. Lurie said. “He complained that he couldn’t sleep and that he had terrible headaches. He could not write, he did not want to work,” Dr. Lurie said. He wrote to Alexei Maximovich Gorky, “I am so tired, I do not want to do anything at all.” But he nonetheless was planning a political attack on Stalin, Dr. Lurie said. And Stalin, well aware of Lenin’s intentions, sent a top-secret note to the Politburo in 1923 claiming that Lenin himself asked to be put out of his misery. The note said: “On Saturday, March 17th in the strictest secrecy Comrade Krupskaya told me of ‘Vladimir Ilyich’s request to Stalin,’ namely that I, Stalin, should take the responsibility for finding and administering to Lenin a dose of potassium cyanide. I felt it impossible to refuse him, and declared: ‘I would like Vladimir Ilyich to be reassured and to believe that when it is necessary I will fulfill his demand without hesitation.’” Stalin added that he just could not do it: “I do not have the strength to carry out Ilyich’s request and I have to decline this mission, however humane and necessary it might be, and I therefore report this to the members of the Politburo.”