With all due to respect to President Chavez and what he attempted to bring about in 1992, I think the phrase attempted coup is a better fit to describe it, although both words apply.  A coup d'etat is always related to an attempt to change the ultimate leadership of the state.  But a mutiny often has lesser or even completely unrelated goals.  Sailors or soldiers protesting their specific situation or refusing to carry out orders they see as suicidal or immoral, can be said to engage in mutiny, whether or not they wish to engage in open revolt against the head of state.  They may even see themselves as loyal followers of the head of state, who they may feel would actually be on their side if only he/she knew of all the particulars involved.  
While Chavez's mutiny of 1992 lacked certain features common to most Latin American coup attempts (high ranking officers, involvement of CIA and/or U.S. embassy), it was still an attempt to use part of the state apparatus to quickly overthrow the state, making the term "attempted coup" accurate and more descriptive than simply "mutiny."