The Toffees reached agreement with the Hammers over Heitinga, but in a statement released by his agents on Thursday, the Holland international said he had not been convinced that transfer would be right for him and had therefore called it off.
He added that he was confident, with the interest being shown in him, that he would be able to join another side before the end of the January transfer window.
For the time being, though, Martinez has stressed Heitinga is still part of the Everton squad.
And it remains to seen whether or not the 30-year-old plays in Saturday's FA Cup third-round home clash with QPR, which, after two run-outs in the Capital One Cup, would be only his third appearance of the season.
Asked on Friday at his press conference to preview the QPR game if there had been any further developments in terms of Heitinga, Martinez said: "No. Johnny is coming back today and is going to train and is going to be part of the squad again.
"We agreed terms with West Ham, but obviously it is down to the player feeling it is the right move for his career."
Heitinga has spoken about his desire to play for his country at this summer's World Cup, a goal he is convinced he will need to find regular first-team football in order to achieve.
Another Everton player who has had limited game time this season and is hoping to feature at the tournament in Brazil is striker Nikica Jelavic.
The Croatia international - also the subject of interest from other clubs - could make his first start since September in the QPR match and Martinez insists Jelavic is still a "very important player in our team".
But asked if he would consider offers for 28-year-old, the Spaniard said: "If it is a situation where Niki can play football and it could prepare his World Cup campaign, and as a football club we get a deal which allows us to move on, we would look into it and consider it. I think we have been very open with that.
"It is only fair that we are open and we need to try to see every situation that is on the table for the future of the two players.
"Niki and Johnny are in a very similar situation, but until that changes, I consider them to be two massive players in the squad and day-to-day, for me they are very important."
Meanwhile, Martinez has expressed his surprise at the controversy surrounding referee Mark Clattenburg and the Premier League game between Everton and Southampton that he oversaw on December 29.
Press Association Sport understands the Saints lodged a complaint with Professional Game Match Officials Limited (PGMOL) in the wake of their 2-1 defeat at Goodison Park, claiming Clattenburg verbally abused their midfielder Adam Lallana.
Asked about that on Friday, Martinez said: "That is the first time I've heard that.
"I thought Mark Clattenburg had a very good game in terms of controlling the players and showing a great manner, and I'm quite surprised.
"I don't think that was the case. It is the first time I've heard a comment about that."