After Ramsey had given the Gunners a ninth-minute lead, they were then pegged back by Aleksandr Golovin's curled free-kick, before a Mesut Özil-inspired run of three goals gave Arsene Wenger's men a resounding lead to take to Moscow in a week's time.
Attack over defence
Within the opening minutes it was clear that is was set to be a battle of the two attacking units and not their defence.
The hosts offered a taste of their attacking threat early on after Henrikh Mkhitaryan slashed into the side netting, and after Aaron Ramsey thought he had given Arsenal the lead, the goal was ruled offside after Mesut Ozil was - incorrectly - flagged by the official.
Minutes later however, the Welshman did break the deadlock in the ninth minute. After Hector Bellerin found space on the right, the Spaniard's low driven cross found Ramsey and the midfielder lashed his shot high into the net pass CSKA stopper Igor Akinfeev.
Before the quarter-of-an-hour mark had passed however, the visitors were level. After Laurent Koscielny had clumsily fouled Aleksandr Golovin on the edge of the area, the Russian - who Arsenal had been tenuously linked with in recent months - stepped to curl his free-kick past Petr Cech to level the scores.
Gunners run riot
The goal perhaps predictably shook the hosts who should have then taken the lead through Leicester City loanee Ahmed Musa, but the Nigerian could only shy wide of the target.
Until then, a rather shaky and ageing back line had only been fleetingly tested, but in the space of 12 first-half minutes Arsenal threatened to put the tie to bed after just 90 minutes.
After Mesut Ozil scampered through the CSKA defence, the German was felled in the area. After careful consideration, referee Pavel Kralovec pointed to the spot. Lacazette stepped up to send Akinfeev the wrong way to re-assert the Gunners' lead.
A rampant home side them extended their lead in sumptuous fashion again though Ramsey. Ozil was continuing the pull the strings in midfield, but in typical style the Arsenal forward lofted a delightful ball over the Russian defence. The ball fell to Ramsey who then on the volley lofted a delightful chip over the 'keeper and into the net.
The North Londoners' dominance was then underlined ten minutes from the break as Ozil again provided the pass into the danger area, and after Vasily Berezutskiy failed to clear his lines, the prowling Lacazette composed himself and rifled his effort low into the net from 18 yards.
CSKA had been wasteful in pockets during the piece, and despite their lofty 4-1 lead at half-time, Arsenal could not yet rest on their laurels.
Hosts seek decisive lead
That was clearly the message at the break as Mkhitaryan could have made added a fifth inside a minute of restart but his side-foot effort skewed wide of the far post.
Ramsey also, in search of his second hat-trick of the season was denied his third by defender Sergei Ignashevich, who blocked his shot with the ball spinning wide of the far post.
The lively Welshman was then denied twice in quick succession by Akinfeev close in, after more slack work at the back by the visitors.
CSKA were still a threat on the counter-attack as the Russian sought what could yet prove to be a pivotal second away goal ahead on the return leg next week, but were again lacking a cutting edge up front, as a number of chances went by, often ballooned over Cech's crossbar and a bigger threat to the upper tiers of the stadium.
It was then Lacazette's chance to bag his triple but missed a golden opportunity to complete his hat-trick. As the entire CSKA back line stepped up, four men in red shirts were played on and as substitute Alex Iwobi fed Lacazette at the far stick, the French managed to miss an open goal, albeit from a tight angle.
Ozil was denied also by smart low save by Akinfeev, before Ramsey clattered the post from the edge of the box, as the Welshman was frustrated in his attempts grab his own triple.
For the most part CSKA were now reduced to spectators has the visitors clung on to take hope into the second leg.
Arsenal should have extended their lead further in the closing minutes, and may yet rue a handful of misses, but the Gunners will be confidence of converting their advantage in a seven days time in the Russian capital.